Dissertação(mestrado) - Universidade Federal do Rio Grande, Programa de Pós–Graduação em Oceanografia Biológica, Instituto de Oceanografia, 2005. / Submitted by Cristiane Gomides (cristiane_gomides@hotmail.com) on 2013-10-09T16:00:18Z No. of bitstreams: 1 Denise.pdf: 786595 bytes, checksum: 5f8cea4a7c4ffd5cc4c20c56dd9c2352 (MD5) / Approved for entry into archive by Sabrina Andrade (sabrinabeatriz@ibest.com.br) on 2013-10-17T03:04:44Z (GMT) No. of bitstreams: 1 Denise.pdf: 786595 bytes, checksum: 5f8cea4a7c4ffd5cc4c20c56dd9c2352 (MD5) / Made available in DSpace on 2013-10-17T03:04:44Z (GMT). No. of bitstreams: 1 Denise.pdf: 786595 bytes, checksum: 5f8cea4a7c4ffd5cc4c20c56dd9c2352 (MD5) Previous issue date: 2005 / A camada de gordura das toninhas, Pontoporia blainvillei, foi estudada partir de medidas de espessura e análise da composição de ácidos graxos. Os animais analisados foram capturados acidentalmente pele frota pesqueira de emalhe do Rio Grande (32º 05’S e 52º 08’W), entre 1999 e 2003. Com objetivo de investigar a possibilidade do uso da espessura da camada de gordura na estimativa da condição corporal nesta espécie, foram tomadas medidas de espessura em 116 indivíduos. As medidas de espessura foram obtidas nas regiões dorsal, ventral e lateral de uma mesma circunferência do corpo, localizada entre as nadadeiras peitoral e dorsal. A maturidade sexual dos animais foi determinada a partir do exame macroscópico e histológico das gônadas. A composição e a estratificação de ácidos graxos (AG) foi estudada a partir de amostras da região médio-ventral da camada de gordura de 30 indivíduos, sendo a idade destes estimada através dos grupos de camadas de crescimento dos dentes. As amostras da camada de gordura foram subdivididas em três estratos de profundidade (pele-músculo). Os lipídios de cada estrato foram extraídos utilizando-se solução (2:1) de clorofórmiometanol e os ésteres metílicos de ácidos graxos foram extraídos com solução BF3 – metanol e posteriormente analisados por cromatografia gás-líquida. A identificação de cada ácido graxo foi feita pela comparação dos tempos de retenção das amostras com o de misturas-padrão comercializadas. Os filhotes apresentaram menor espessura de camada de gordura na região dorsal em relação aos maduros e imaturos. Enquanto os machos não apresentaram diferenças entre maduros e imaturos com relação à espessura, fêmeas maduras possuíram maior espessura da camada de gordura dorsal do que as imaturas. Foi detectada variação sazonal a partir da espessura da camada de gordura apenas na região ventral, sendo que as menores espessuras foram registradas no outono e as maiores no inverno. A variação interanual foi evidenciada na espessura dorsal da camada, sendo que os indivíduos capturados em 2002 apresentaram melhor condição corporal do que os indivíduos capturados em 2000 e 2001, o que possivelmente foi resultante de mudanças nas condições ambientais e na disponibilidade de presas. Um total de 27 ácidos graxos foram identificados, sendo que o 16:1n-7 e o 18:1n-9 estiveram presentes em maiores concentrações (em média 37,14% e 19,70%, respectivamente). A maioria dos AG apresentou gradiente contínuo através dos estratos, aumentando ou diminuindo de concentração do sentido externo (adjacente à pele) para o interno (adjacente ao músculo). Os AG saturados e monoinsaturados de cadeias mais curtas (12:0, 18:0, 14:1n-5 e 15:1) apresentaram os maiores graus de estratificação, aumentando de concentração no sentido do estrato externo. Já os AG poliinsaturados (PUFAs) 20:3, 20:5n-3, 22:6n-3, 20:4n-6 e 22:2 e o monoenóico 24:1n-9 apresentaram maior estratificação no sentido do estrato interno. A composição e a estratificação dos AG também foram diferentes entre as classes etárias e entre os sexos. O total de PUFAs no estrato interno aumentou com a idade e esta relação foi mais forte em machos. O total de AG saturados presentes no estrato externo diminuiu com a idade, sendo esta relação mais forte em fêmeas. Não foram encontradas correlações entre a idade e a razão de omega-3/ omega-6 para os estratos externo ou interno. Entre os adultos, os machos apresentaram maior grau de estratificação do que fêmeas. O presente estudo mostra a possibilidade de utilizar-se a espessura da camada de gordura na região dorsal como um indicador da condição corporal em toninhas e evidencia variabilidade na composição de AG dos indivíduos, dando aporte para futuras investigações sobre análises de dieta ou diferenciação de estoques populacionais nesta espécie através da composição de AG. / In order to investigate the usefullness of blubber thickness to estimate the body fat condition in Pontoporia blainvillei, axillary girth measurements were taken from dorsal, ventral and lateral regions, between the pectoral flipper and the dorsal fin. Blubber measurements were obtained for 116 franciscana dolphins, accidentally caught by the coastal artisanal fishery from Rio Grande (32º 05’S e 52º 08’W), between 1999 e 2003. Sexual maturity was determined from macroscopic and histological analysis of gonads. Dorsal blubber thickness (DBT) had the highest variation among the 3 measurements taken, and was considered the best measurement assess body fat condition in this species. DBT was lowest for pups and highest for mature females. Immature and mature males did not differ in DBT measurements. Dorsal blubber thickness also exhibited inter-annual variation such that 2002 individuals had thicker layers and thus better body condition that those accidentally caught in 2000 and 2001. Ventral blubber thickness (VBT) did not vary as much as DBT but seemed to be affected by seasonality. VBT was lowest in the fall and highest in the winter. Interannual variation in blubber thickness may be the result of changing environment conditions and/or prey composition, condition and availability. This study showed the potential use of blubber thickness as a proxy to estimate body fat condition in franciscana dolphins. Additionally, the fatty acid composition and stratrification of the blubber layer (skin-muscle) at the middle-ventral region was studied in 30 franciscanas. The lipids were extracted using chloroform-methanol and fatty acids methyl esters were obtained using BF3-methanol. Analyses were performed by gas-liquid chromatography. Fatty acids were identified by comparison of the retention time against commercial standards. Age determination estimated by counting GLGs (Growth Layer Groups) from teeth. Twenty-seven fatty acids were quantified (27/37), of which 16:1n-7 (37,14%) and 18:1n-9 (19,70%) exhibited the highest concentrations. Stratification of fatty acid concentration across the blubber layer was found where a continuous gradient of FA concentrations was evident either increasing or decreasing from the inner layer towards the skin. The shorter-chain saturated and monounsaturated fatty acids (12:0, 18:0, 15:1 and 14:1n-5) exhibited the highest relative amounts in the outer layer whereas polyunsaturated fatty acids (PUFA) 20:3, 20:5n-3, 22:6n-3, 20:4n-6 and 22:2 and the monounsaturated fatty acid 24:1n-9 exhibited the highest relative amounts in the inner blubber layer. The array of fatty acids identified differed among age categories and between females and males. Total PUFA in the inner layer increased with the age and this relationship was stronger for male franciscanas. On the other hand, total saturated fatty acids found in the outer layer decreased with the age an this relationship was stronger for females. There was no correlation between the ratio omega-3/ omega-6 and the age of the individuals for either the outer or inner blubber layer. The strongest degree of stratification was exhibited by adult males. This study describes for the first time the existence of stratification and the fatty acid composition of the blubber layer of franciscana dolphins from FMA IIIs.

FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / Foram objetivos deste estudo, (i) conhecer as concentraÃÃes hormonais de leptina e insulina em ovelhas, bem como verificar o efeito do escore de condiÃÃo corporal (ECC), do grupo genÃtico e da suplementaÃÃo sobre as concentraÃÃes de leptina, insulina e glicose mensuradas durante a estaÃÃo de monta, e ainda estudar as associaÃÃes entre estes efeitos e os metabÃlitos sanguÃneos em ovelhas vazias; (ii) avaliar a influÃncia dos efeitos da classe de condiÃÃo corporal, idade, semana de coleta, grupo genÃtico e da suplementaÃÃo energÃtica fornecida antes e durante a estaÃÃo de monta, sobre o peso e a condiÃÃo corporal das fÃmeas, e a influÃncia destes efeitos sobre os parÃmetros reprodutivos, taxa de gestaÃÃo, fertilidade e prolificidade; (iii) e ainda, avaliar os efeitos que exercem influÃncia sobre o peso da ovelha ao parto, o peso da cria ao nascer e sobre a produtividade total das ovelhas do rebanho, traduzida no presente estudo em quilos de cordeiro produzido por fÃmea parida. O experimento foi conduzido na Fazenda Experimental Vale do AcaraÃ, situada no municÃpio de Sobral â CearÃ. As ovelhas foram divididas em dois grupos segundo o grupo genÃtico e o tratamento: Santa InÃs com ou sem suplementaÃÃo (24x24) e Morada Nova com ou sem suplementaÃÃo (24x24), totalizando 96 ovelhas. Todas as fÃmeas foram manejadas em piquetes com mineralizaÃÃo e Ãgua ad libitum, porÃm o grupo 1 (controle) de cada tratamento nÃo foi suplementado e o grupo 2 recebeu suplementaÃÃo. Foram realizadas semanalmente coletas de sangue e informaÃÃes referentes ao peso e ECC das ovelhas. Os dados foram submetidos à ANOVA para se avaliar o efeito da classe de ECC, grupo genÃtico e suplementaÃÃo (lote), sobre o peso corporal, concentraÃÃes de glicose e concentraÃÃes de leptina e insulina, peso e a produtividade das ovelhas. Os parÃmetros reprodutivos como, taxa de gestaÃÃo, fertilidade e prolificidade foram comparados pelo teste de c 2 com 5% de probabilidade de erro. Foram estimadas as correlaÃÃes simples de Pearson entre as concentraÃÃes hormonais, peso e condiÃÃo corporal em funÃÃo do grupo genÃtico e tratamento. Constatou-se que a leptina està presente em baixas concentraÃÃes em ovelhas deslanadas e nÃo influenciando os processos reprodutivos destes animais sob essas condiÃÃes de criaÃÃo. A insulina mostrou importantes associaÃÃes com as variÃveis estudadas, podendo ser indicativa da condiÃÃo nutricional das ovelhas em estaÃÃo de monta. A suplementaÃÃo energÃtica promoveu o aumento do peso e melhorou o escore de condiÃÃo corporal das fÃmeas, nÃo refletindo, contudo, sobre os parÃmetros reprodutivos das ovelhas. O peso corporal das fÃmeas à pariÃÃo à influenciado pelo grupo genÃtico e idade da ovelha. Jà o peso ao nascer dos cordeiros pode ser influenciado pelo tipo de nascimento, peso da ovelha à pariÃÃo e pelo sexo da cria. O escore de condiÃÃo corporal, o genÃtipo e o tipo de nascimento influenciam na produtividade em quilos de cordeiro por ovelha parida. Entretanto, o fornecimento de suplementaÃÃo durante a estaÃÃo de monta nÃo resultou no aumento da produtividade em quilo de cordeiro produzido por ovelha parida no rebanho. Diante do exposto, conclui-se que o fornecimento de suplementaÃÃo energÃtica, para ovelhas deslanadas criadas na regiÃo semiÃrida do nordeste brasileiro, quando manejadas em sistema de pastejo rotacionado recebendo mineralizaÃÃo e Ãgua ad libitum pode ser dispensada, uma vez que a sua oferta onerou os custos de produÃÃo e nÃo resultou em aumento significativo na produtividade das ovelhas. / Through this study it is aimed, (i) to know the leptin and insulin concentrations in sheep, as well as to verify the effect of body condition score (BCS), breed and supplementation on the leptin, insulin and glucose concentrations measured during the breeding season, and also to study the associations between these effects and blood metabolites in empty sheep (ii) to evaluate the influence of class effects of body condition, age, collection week, breed and energy supplementation provided before and during the breeding season, on female weight and body condition, and the influence of these effects on reproductive parameters, pregnancy rate, fertility and prolificity; (iii)and also to evaluate the effects which influence the ewe weight at lambing, the offspring weight at birth and on the total productivity of the flock, referred to in the present study in pounds of lamb produced per female lambing. The experiment was conducted at the Experimental Farm Acaraà Valley, located in the municipality of Sobral - CearÃ. The sheep were divided into two groups according to breed and treatment: Santa InÃs, with or without supplementation (24x24) and Morada Nova with or without supplementation (24x24), totalizing 96 sheep. All ewes grazed in paddocks with mineralization and water ad libitum, however group 1 (control) of each treatment was not supplemented and group 2 received supplementation. Blood samplesand information relating to sheep weight and BCS were collected weekly during the breeding season. Data were submitted to ANOVA to evaluate the effect of the BCS class, breed and supplementation (lot), on body weight, glucose levels and leptin and insulin concentrations, ewe weight and sheep productivity The ewe reproductive parameters, pregnancy rate, fertility and prolificity were compared with test having 5% of error probability. Pearson correlation were estimated among hormone concentrations, weight and body condition related to breed and treatment. It was concluded that leptin is present in low concentrations in hair seep sheep and it seems not to influence the reproductive processes of those animals raised under these conditions. Insulin showed significant associations with the variables studied, which may be indicative of nutritional status of ewes in the breeding season. Energy supplementation promoted weight gain and improved body condition score of females. However, its effect was not reflected on the ewe reproductive parameters. The body weight of females at parturition is influenced by ewe breed and age. The lamb birth weight can be influenced by the type of birth, ewe weight at lambing and sex of the offspring. The body condition score, breed and type of birth influence productivity in kilograms of lamb per ewe parity. However, the supply of supplementation during the breeding season did not result in increased productivity per kilogram of lamb produced per female lambing. According to what was exposed above, it can be concluded that the supply of energy supplementation for hair seep ewes raised in the semi-arid region of Northeastern Brazil, raised under rotational grazing and receiving mineralization and water ad libitum, resulted in no significant increase in sheep productivity and can, therefore, be waived.

A presente tese foi dividida em 5 Experimentos. Os objetivos do Experimento 1 foram avaliar a utilização da gonadotrofina coriônica equina (eCG) e/ou do cipionato de estradiol (ECP) na dinâmica folicular e taxa de concepção de vacas holandesas submetidas a inseminação em tempo fixo (IATF). No D0, todos os animais (n = 782) receberam 2 mg de benzoato de estradiol (BE) e um dispositivo intravaginal de progesterona (CIDR). Oito dias depois, o CIDR foi retirado e todos os animais receberam PGF2?. Simultaneamente, os animais foram divididos em 4 grupos: G1) eCG + ECP no Dia 8; G2) eCG no Dia 8 + GnRH após 48h; G3) ECP no Dia 8; G4) GnRH após 48h. Amostras de sangue e exames utlra-sonográficos foram realizados frequentemente em um subgrupo de animais (n = 96). As análises estatísticas de todos os experimentos foram efetuadas com o proc GLIMMIX e proc MIXED do SAS. O uso de eCG e o escore de condição corporal (ECC) dos animais afetaram as concentrações circulantes de progesterona no diestro. Os animais do G2 apresentaram maior taxa de concepção que os do G4 (33,8% vs. 28,9%). Além disso, para animais de menor ECC, ficou evidente o benefício da aplicação de eCG (G2 = 44,4% vs. G4 = 6,1%). No Experimento 2 (n = 26), o objetivo foi comparar o efeito da administração da eCG no dia da remoção do CIDR em animais de menor (2,0-2,5) ou maior (3,0-3,5) ECC. Foram avaliadas algumas características do corpo lúteo (CL) como o volume e histologia, assim como as concentrações plasmáticas de progesterona no diestro. Independentemente da condição corporal dos animais, a eCG aumentou o volume do CL e a concentração plasmática de progesterona no diestro. O ECC afetou negativamente o volume e concentração de progesterona sérica no diestro. Não foi encontrado diferença na proporção de células grandes/pequenas, assim como no fluxo sanguíneo no CL entre os grupos experimentais. No Experimento 3, foi comparado a taxa de concepção em vacas de leite de alta produção (n = 388) após o uso do protocolo G2 do Experimento 1 (Capítulo I), com ou sem adição de ECP no momento da retirada do CIDR (novo ou usado). Não foi verificado efeito da adição do tratamento com ECP e nem do tipo do dispostivo na taxa de concepção. No Experimento 4 (n = 199), apesar no aumento verificado no diâmetro folicular no grupo tratado com GnRH 56h (17,8 mm) comparado com GnRH 48h (16,5 mm); e do atraso no momento da ovulação após a retirada do CIDR (GnRH 56h = 75,3h; GnRH 48h = 79,8h) não foi constatado qualquer diferença na concepção ao se atrasar a aplicação do GnRH de 48h para 56h em vacas inseminadas 16h depois do GnRH. No Experimento 5 (n = 185), a taxa de concepção não diferiu em animais que receberam o GnRH 48h ou 56h (momento da IATF) após a retirada do CIDR, indicando a possibilidade do emprego de um protocolo com apenas 3 manejos em vacas de leite de alta produção. / The current thesys has been divided in 5 Experiments. Objectives of Experiment 1 were to evaluate the effects of equine chorionic gonadotropin (eCG) and/or estradiol cypionate (ECP) on follicular dymanics and conception rate in Holstein cows receiving fixed timed artificial insemination (TAI). On D0, all cows (n = 782) received 2 mg of estradiol benzoate (EB) and one intravaginal progesterone device (CIDR). Eight days later, CIDR was removed and all animals were treated with PGF2?. Simultaneously, animals were divided in 4 groups: G1) eCG + ECP on Day 8; G2) eCG on Day 8 + GnRH 48h later; G3) ECP on Day 8; G4) GnRH 48h later. Blood samples and ultrasound exams were frequently performed in a subset of the animals (n = 96). All the statistical analyses for all experiments were performed with proc GLIMMIX and proc MIXED of SAS. Equine chorionic gonadotropin (eCG) treatment and body condition score (BCS) affected circulating progesterone in the diestrus. Cows in G2 had greater conception rates than cows in G4 (33,8% vs. 28,9%). In addition, in cows with lower BCS, eCG seems to be even more affective (G2 = 44,4% vs. G4 = 6,1%). In Experiment 2 (n = 26), the objective was to compare the effect of eCG the day of CIDR removal in animals with lower (2,0-2,5) or higher (3,0-3,5) BCS. Some variables such as corpus luteum (CL) volume, histology and circulating progesterone concentration in the diestrus were evaluated. Regardless of the body condition of the animals, eCG increased CL volume and circulating progesterone concentration in the diestrus. BCS negatively affected CL volume and circulating progesterone. There were no differences in large/small CL cell ratio, as well as CL blood flow between experimental groups. In Experiment 3, it was compared conception rate in dairy cows (n = 388) after using the same protocol G2 from Experiment 1 (Chapter I), with or without an ECP treatment at the time of CIDR (new or used) removal. Both ECP treatment and type of CIDR did not significantly affected conception rates. In Experiment 4 (n = 199), despite the fact that follicular diameter was increased in group GnRH 56h (17,8 mm) compared with GnRH 48h (16,5 mm); and of the delayed time of ovulation after CIDR removal (GnRH 56h = 75,3h; GnRH 48h = 79,8h), there were no differences in conception rates after delaying the GnRH treatment from 48h to 56h in cows inseminated 16h after GnRH. In Experiment 5 (n = 185), conception rate did not differ in animals that received GnRH 48h or 56h (at the time of TAI) after CIDR removal, indicating the possibility of using a protocol with only 3 handlings in high producing dairy cows.

L’amélioration de l’efficience alimentaire des animaux peut contribuer à un élevage plus durable par la réduction des ressources utilisées et des rejets associés. Les caractères qui déterminent l’efficience alimentaire des vaches laitières restent mal identifiés. Le projet se propose donc d’identifier les facteurs biologiques associés à la variabilité interindividuelle de l’efficience alimentaire des vaches laitières. La variation d’efficience alimentaire a été estimée avec l’ingéré résiduel, classiquement défini comme la variabilité résiduelle de l’énergie nette ingérée corrigée pour l’énergie nette du lait, l’entretien et les variations de réserves corporelles. Cet ingéré résiduel inclut par définition toutes les erreurs de mesure. Pour réduire ces erreurs, la note d’état corporel, qui classiquement se fait par notation visuelle, a été automatisée et de nombreux autres caractères candidats ont été mesurés fréquemment dans un environnement stable sur quasiment toute la lactation.La variabilité de l’ingéré résiduel ne représentait que 8% de la variabilité de l’ingéré mesuré, dont 58,9% étaient associés à de l’efficience et non de l’erreur. L’étude de la répétabilité de cet ingéré résiduel au cours de la lactation suggère d’éviter les 7 premières quinzaines au profit du milieu de lactation. Parmi tous les caractères mesurés, le comportement alimentaire, la température ruminale, la variation des réserves corporelles et l’activité expliquaient 58,9% de la variabilité de l’ingéré résiduel. Les effets de plusieurs de ces caractères semblent confondus. Leur lien de causalité av / Achieving higher feed efficiency of animals is expected to improve animal production sustainability through reduction of the used resources and of the associated emissions. The traits determining feed efficiency remain poorly understood. The present project aimed therefore at identifying the biological factors associated with feed efficiency differences in lactating dairy cows. Feed efficiency variation was estimated with the traditional residual intake, which was defined as the residual variability of net energy intake which is not explained by net energy required for lactation, maintenance and body reserves change. This residual intake includes by definition all measurement errors. To reduce these errors, body condition score, which is commonly measured visually, has been automated and several other candidate traits were measured frequently in a steady environment for almost whole lactation.Residual intake variability represented only 8% of intake variability in our study, among which only 58.9% were found to be associated with feed efficiency variability and not to errors. The repeatability analysis of the residual intake throughout the lactation suggested to avoid the 7 first lactation fortnights, and rather to focus on lactation middle. Among all measured traits, feeding behaviour, rumen temperature, body reserves change and activity explained 58.9% of residual intake variability. Many of these traits seemed confounded with others, which claimed for the need for further work to properly define their causal relationship with feed efficiency, especially focussing on di

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The objective of this dissertation was to evaluate the performance of lactating sows and their piglets fed with high moisture corn diets with or without acidifiers. Fifteen sows of commercial genetic lines were used in a randomized complete block with three treatments (negative control diet elaborated each 24h; control diet with 0.5% of benzoic acid elaborated each 24h; control diet with 0.5% of fumaric acid elaborated each 24h) with five replications each. Diets elaborated with high moisture corn with benzoic or fumaric acids did not modify (P>0.05) the backfat thickness. The average daily feed intake (7.93kg/NM) of lactating sows was not influenced (P>0.05) by treatments. The average daily weight gain (0.22kg) and average weaning live weight (6.2kg) of piglets were not influenced (P>0.05) by diets with benzoic or fumaric acids. The addition of fumaric acid in diets of lactation sows decreased (P<0.05) the liquid feces frequency in piglets comparated with negative control diet. The addition of acidifiers in diets containing high moisture corn does not alter performance of lactating sows neither their piglets. / O objetivo desta dissertação foi avaliar o desempenho de porcas lactantes e suas leitegadas alimentadas com dietas contendo silagem de grãos úmidos de milho com ou sem acidificantes. Foram utilizadas quinze porcas de genética comercial em um delineamento de blocos ao acaso com três tratamentos (dieta controle negativo elaborada a cada 24h; dieta com adição de 0,5% de ácido benzóico elaborada a cada 24h e dieta com adição de 0,5% de ácido fumárico elaborada a cada 24h) com cinco repetições cada. As dietas elaboradas com silagem de grãos úmidos de milho com ácidos benzóico ou fumárico não alteraram (P>0,05) a espessura de toicinho. O consumo diário de alimento das porcas lactantes foi de 7,93kg/MN não variando (P>0,05) entre os tratamentos. O ganho médio diário de peso dos leitões foi de 0,22kg, não variando (P>0,05) entre os tratamentos. O peso vivo médio dos leitões ao desmame foi de 6,2kg não diferindo (P>0,05) entre leitões de porcas lactantes alimentadas com dietas com ácido benzóico ou fumárico. No período total de 21 dias, a adição de ácido fumárico na dieta de porcas lactantes diminuiu em 30% (P<0,05) a freqüência de fezes líquidas dos leitões em relação à dieta controle. A adição de ácidos fumárico e benzóico em dietas elaboradas com silagem de grãos úmidos de milho não alteram os desempenhos de porcas lactantes e nem o de suas leitegadas.

Ziel dieser Arbeit war eine Untersuchung zur Häufigkeit des Wechsels von Legehennen zwischen Innen- und Außenbereichen, einschließlich der Aufenthaltsdauer außerhalb des Stalles, in Relation zum Federpicken und der Beschaffenheit des Integumentes. Der Einfluss der Haltungsbedingungen und der Einfluss des Genotyps wurden untersucht. Die Gruppe, die ohne Grünauslauf war, bewegte sich signifikant häufiger zwischen dem Stall und dem Wintergarten als andere Gruppen mit Grünauslauf. Die Aufenthaltsdauer im Stall und Wintergarten war in der Gruppe ohne Grünauslauf signifikant höher als bei anderen mit Grünauslauf (GA). Hennen, denen eine große Auslauffläche angeboten wurde (10m²/T) bewegten sich signifikant häufiger zu den Außenbereichen als andere mit einem Angebot von 2,5 m²/Tier. Hennen mit einem Angebot von 2,5 m²/Tier hielten sich länger auf dem Grünland auf als Hennen mit einer Besatzdichte von 10m²/T. Die höchsten Federpickaktivitäten waren in der Gruppe ohne GA im Vergleich zu den Gruppen mit GA. Im Vergleich zu anderen Gruppen mit GA, hatte die Gruppe ohne GA einen schlechteren Gefiederzustand. LSL Hennen bewegten sich im Vergleich zu den LT Hennen häufiger zwischen Innen- und Außenbereichen. LSL Hennen hielten sich im Vergleich zu den LT Hennen länger im Wintergarten auf. Dennoch hielten sich die LT Hennen im Vergleich länger auf dem Grünland auf. Die schlechteste Gefiederbeschaffenheit wiesen LSL Hennen im Vergleich zu LT Hennen auf. Die Resultate der vorliegenden Untersuchungen weisen darauf hin, dass die Auslaufnutzung einen positiven Einfluss auf den Gefieder- und Hautzustand hat. Die untersuchten Genotypen unterschieden sich in der Häufigkeit des Ortswechsels und der Aufenthaltsdauer im Grünauslauf. / The aim of this work was to investigate the frequency of movement of laying hens between indoor and outdoor enclosures and the time hens spent outside the hen house in relation to feather pecking and condition of the integument. The effect of housing condition and the genotype were studied. Hens that were offered a large space to outside open area (10m²/bird) moved significantly more frequently to the outdoor areas than others (2.5m²/bird). Frequency of movement between poultry house and winter garden was higher in the group without grassland. Hens kept at a higher density outdoors (2.5m²/bird) spent significantly more time in this area than hens were kept at a lower density (10m²/bird) on grassland. The high rates of feather pecking are observed in the group without grassland compared to groups stocked at 2.5m² or 10m² per bird on grassland The group without grassland had poorer feather condition compared to other groups that had 2.5m²/bird and 10m²/bird on grassland Lohmann Selected Leghorn (LSL) hens moved more frequently to the outdoor enclosures compared to Lohmann Tradition (LT). But LT hens spent significantly more time on grassland than LSL.The plumage condition was worse in LSL than LT hens. It is concluded that housing conditions might have a stronger influence on the development of feather pecking than the genetic aspect. Large differences between the genotypes examined were found in respect to the frequency of movement to the outdoor areas, the time spent outside and plumage and skin damage.

Productivity of grey rhebok and mountain reedbuck was studied at Sterkfontein Dam Nature Reserve (eastern Free State) between September 1999 and May 2002. Within a study area of 550 ha, all herds of grey rhebok and all territorial male mountain reedbuck were identified, and general population dynamics were monitored. Lambs of both species were born seasonally between September and February, while most deaths occurred between June and November. Population levels appeared to be controlled in both species mainly by the eviction of young males, but the effects of extreme weather conditions were significant, being demonstrated by the deaths of 27 % and 51 % of the grey rhebok and mountain reedbuck populations respectively during heavy snow in September 2001. Disease and predation played no role in population control. Grey rhebok formed stable harem herds with home ranges varying between 23 ha and 104 ha (95 % MCP), with an average of 57.9 ha. Home ranges in areas with extensive steep slopes tended to be smaller than those in flatter areas. The ecological density was 1/15.7 ha. Territorial male mountain reedbuck were often solitary, and only accompanied by females when these moved into their territories. Home ranges of males varied between 7 ha and 21 ha (95 % MCP), with an average of 14.8 ha, and all had areas of steep slopes within. Females showed strong preference for steep slopes and used much greater areas than males. The ecological density was 1/8.7 ha. Grey rhebok rested less than mountain reedbuck, but did not feed for longer. Grey rhebok were active intermittently all day and night, but tended to be more active in the early morning and late afternoon than in the middle of the day. During the day, mountain reedbuck were most active in the late afternoon, rested for longer periods in the middle of the day, but were also very active at night. Body condition was investigated seasonally in mountain reedbuck at Sterkfontein and also Tussen die Riviere Nature Reserve. Kidney fat indices and leg fat percentages were lowest at the end of winter before the rains started and when the nutritive value of the veld was at its lowest. Endoparasites were investigated in both antelope species, but primarily in mountain reedbuck. Seventeen species of helminths, including fifteen nematodes, one trematode, and one cestode were recovered from mountain reedbuck at Sterkfontein and TdR. The most prevalent and abundant species were Cooperia yoshidai, Longistrongylus schrenki and Haemonchus contortus. Five nematode species were recovered from four grey rhebok at Sterkfontein. / Thesis (PhD (Veterinary Wildlife))--University of Pretoria, 2004. / Veterinary Tropical Diseases / unrestricted

Tesis por compendio / The thesis is composed for four articles, where is studied either as relationships between body condition and energetic mobilization in rabbits and as the effect of selection for litter size variability in body condition and energetic mobilization, such as welfare biomarkers, and in litter size and its components after seven generation of selection. The first article examines the relationships between measures of body condition and energetic mobilization on primiparous rabbit at mating, delivery and 10 d after delivery, using principal component analysis. Body condition was measured as body weight and perirenal fat thickness. Energetic mobilization was measured as non-esterified fatty acid concentration in blood, before (NEFAb) and after lipolysis stimulation by isoproterenol (NEFAr). All body weights and perirenal fat thickness were located on the first principal component, exhibiting high correlations between them both at the same or different times (from 0.51 to 0.83). All NEFA measurements were located on the second component, showing low correlations with body condition measurements. Both NEFAs showed high positive correlations when measured at the same time (0.65 at mating, 0.72 at delivery and 0.69 at 10 d after delivery), but low correlations when measured at different times (from 0.09 to 0.20). The second article analyses the correlated response in body condition and fat reserves mobilization. The perirenal fat thickness and the increase in NEFAs from basal until adrenergic stimulation by isoproterenol were measured at second mating, at delivery and at 10 d after delivery. Perirenal fat thickness was similar in both lines at mating. However, the high line showed lower fat thickness than the low line at delivery (-0.16 mm, P=0.86), and this difference remained at 10 d after delivery (-0.17 mm, P=0.86). Moreover, this line exhibited 30% more concentration in NEFAs at delivery than the low one (P=0.96). The third and fourth articles study the correlated responses to selection in litter size and its components. A laparoscopy was performed 12 d of the second gestation, in order to estimate ovulation rate and number of implanted embryos. The litter size was recorded at the second parity. In the last gestation, the embryonic development was analysed at 28, 48 and 72 hours of gestation. The ovulation rate was similar in both lines. The line selected to reduce variability in litter size showed a higher number of implanted embryos (1.23, P=1.00) than the high line. Also, this line showed a more advanced development of the embryos from 48 hours of gestation, exhibiting a lower percentage of early morulae both at 48 hours (53.32% vs 79.90%, P=0.93) and at 72 hours (3.88% Vs. 21.04%, P=0.93). More advanced embryo development is related to higher embryo survival (0.85 vs 0.78, P=1.00). A higher uterine overcrowding of embryos in the low line did not penalise fetal survival, and as a result, this line continued showing a greater number of kits born at birth (0.98, P=0.96). In conclusion, body weight and perirenal fat thickness are good predictors of body reserves and both measurements could be used to estimate energy changes in the mid-long term, while NEFA measurements should be used in the short term. A decrease in litter size variability has a favourable effect on body condition, fat reserve mobilization, embryonic development and survival, and litter size. / La tesis se compone de cuatro artículos, donde se estudia tanto la relación entre la condición corporal y la movilización de energía en la coneja como el efecto de la selección divergente por variabilidad del tamaño de camada en la condición corporal y movilización de reservas energéticas, como biomarcadores del bienestar del animal, y en el tamaño de camada y sus componentes después de siete generaciones de selección. El primer artículo examina las relaciones entre las medidas de la condición corporal y la movilización de energía en conejas primíparas a la monta, al parto y a los 10 días tras el parto, a través de un análisis de componentes principales. La condición corporal se midió como el peso corporal y el espesor de grasa perirenal. La movilización de energía se midió como la concentración de ácidos grasos no esterificados en sangre, antes (NEFAb) y después de la estimulación lipolítica con isoproterenol (NEFAr). Todos los pesos y espesores de grasa perirenal se situaron sobre la primera componente principal, exhibiendo altas correlaciones entre ellos independientemente del estado fisiológico donde se midieron (de 0.51 a 0.83). Todas las medidas de NEFAs se localizaron sobre la segunda componente principal, mostrando una baja correlación con las medidas de la condición corporal. Los NEFAb y NEFAr mostraron elevadas correlaciones entre ellos cuando se midieron en el mismo momento (0.65 a la monta, 0.72 al parto y 0.69 a los 10 días tras el parto), pero bajas correlaciones cuando se midieron en diferentes momentos (de 0.09 a 0.20). El segundo artículo analiza la respuesta correlacionada sobre la condición corporal y la movilización de reservas grasas. El espesor de la grasa perirenal y el incremento de los niveles basales de NEFAs después de su estimulación adrenérgica con isoproterenol fueron medidos a la segunda monta, al parto y a los 10 días tras el parto. El espesor de la grasa perirenal fue similar en ambas líneas a la monta. Sin embargo la línea de alta mostró un menor espesor de grasa que la línea de baja al parto (-0.16 mm, P=0.86), y esta diferencia se mantuvo a los 10 días después del parto (-0.17 mm, P=0.86). Por otro lado, esta línea exhibió un 30% menos de NEFAs al parto que la línea de baja (P=0.96). El tercer y cuarto artículo estudian la respuesta correlacionada sobre el tamaño de camada y sus componentes. Se realizó una laparoscopía a los 12 días de la segunda gestación para estimar la tasa de ovulación y el número de embriones implantados. Se contabilizó el tamaño de camada al segundo parto. En la última gestación se analizó el desarrollo embrionario a 28, 48 y 72 horas de gestación. La tasa de ovulación fue similar en ambas líneas. La línea seleccionada para reducir la variabilidad en tamaño de camada mostró un mayor número de embriones implantados (1.23, P=1.00) que la línea de alta. También, esta línea mostró un desarrollo de los embriones más avanzado a partir de las 48 horas de gestación, exhibiendo un menor porcentaje de mórulas tempranas tanto a 48 horas (53.32% vs 79.90%, P=0.93) como a 72 horas (3.88% vs 21.04%, P=0.93). Un desarrollo más avanzado del embrión está relacionado con una mayor supervivencia de éste (0.85 vs 0.78, P=1.00). Por otro lado, un mayor atestamiento de embriones en el útero de la línea de baja variabilidad no penalizó la supervivencia fetal, y como resultado, esta línea continuó mostrando un mayor número gazapos al parto (0.98, P=0.96). En conclusión, el peso y el espesor de grasa perirenal son buenos predictores de las reservas corporales, ambas medidas podrían usarse para estimar los cambios energéticos a medio plazo, mientras que las medidas de NEFAs se deberían usar a corto plazo. La disminución de la variabilidad del tamaño de camada tiene un efecto favorable sobre la condición corporal, la movilización de reservas grasas, el desarrollo y supervivencia embrionaria y el tam / La tesi es compon de quatre articles, on s'estudia tant la relació entre la condició corporal i la mobilització d'energia en la conilla com l'efecte de la selecció divergent per variabilitat de la grandària de ventrada en la condició corporal i mobilització de reserves energètiques, com biomarcadores del benestar de l'animal, i en la grandària de ventrada i els seus components després de set generacions de selecció. El primer article examina les relacions entre les mesures de la condició corporal i la mobilització d'energia en conilles primípares a la muntada, al part i als 10 dies després del part, a través d'una anàlisi de components principals. La condició corporal es va mesurar com el pes corporal i la grossària de greix perirenal. La mobilització d'energia es va mesurar com la concentració d'àcids grassos no esterificats en sang, abans (NEFAb) i després de l'estimulació lipolítica amb isoproterenol (NEFAr) . Tots els pesos i grossàries de greix perirenal es van situar sobre la primera component principal, exhibint altes correlacions entre ells independentment de l'estat fisiològic on es van mesurar (de 0.51 a 0.83) . Totes les mesures de NEFAs es van localitzar sobre la segona component principal, mostrant una baixa correlació amb les mesures de la condició corporal. Els NEFAb i NEFAr van mostrar elevades correlacions entre ells quan es van mesurar en el mateix moment (0.65 a la muntada, 0.72 al part i 0.69 als 10 dies després del part) , però baixes correlacions quan es van mesurar en diferents moments (de 0.09 a 0.20). El segon article analitza la resposta correlacionada sobre la condició corporal i la mobilització de reserves greixos. La grossària del greix perirenal i l'increment dels nivells basals de NEFAs després de la seua estimulació adrenérgica amb isoproterenol van ser mesurats a la segona muntada, al part i als 10 dies després del part. La grossària del greix perirenal va ser semblant en ambdós línies a la muntada. No obstant això la línia d'alta va mostrar una menor grossària de greix que la línia de baixa al part (-0.16 mm, P=0.86) , i esta diferència es va mantindre als 10 dies després del part (-0.17 mm, P=0.86) . D'altra banda, esta línia va exhibir un 30% menys de NEFAs al part que la línia de baixa (P=0.96). El tercer i quart article estudien la resposta correlacionada sobre la grandària de ventrada i els seus components. Es va realitzar una laparoscopía als 12 dies de la segona gestació per a estimar la taxa d'ovulació i el nombre d'embrions implantats. Es va comptabilitzar la grandària de ventrada al segon part. En l'última gestació es va analitzar el desenrotllament embrionari a 28, 48 i 72 hores de gestació. La taxa d'ovulació va ser semblant en ambdós línies. La línia seleccionada per a reduir la variabilitat en grandària de ventrada va mostrar un nombre més gran d'embrions implantats (1.23, P=1.00) que la línia d'alta. També, esta línia va mostrar un desenrotllament dels embrions més avançat a partir de les 48 hores de gestació, exhibint un menor percentatge de mórulas primerenques tant a 48 hores (53.32% vs 79.90%, P=0.93) com a 72 hores (3.88% vs 21.04%, P=0.93). Un desenrotllament més avançat de l'embrió està relacionat amb una major supervivència d'este (0.85 vs 0.78, P=1.00). D'altra banda, un major atapeïment d'embrions en l'úter de la línia de baixa variabilitat no va penalitzar la supervivència fetal, i com resultat, esta línia va continuar mostrant un nombre més gran errors al part (0.98, P=0.96). En conclusió, el pes i la grossària de greix perirenal són bons predictors de les reserves corporals, ambdós mesures podrien usar-se per a estimar els canvis energètics a mitjà termini, mentres que les mesures de NEFAs s'haurien d'usar a curt termini. La disminució de la variabilitat de la grandària de ventrada té un efecte favorable sobre la condició corporal, la mobilització de reserves greixos, el dese / Calle Ayma, EW. (2017). CORRELATED RESPONSE TO SELECTION FOR LITTER SIZE RESIDUAL VARIANCE IN RABBITS [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/81021 / Compendio

Tesis por compendio / [ES] Cualquier mejora en el conocimiento de la nutrición y el manejo de los futuros conejos reproductores debe considerarse como prioritario en la producción cunícola. Sin embargo, los principales esfuerzos en investigación se han centrado en estos animales durante la fase de reproducción propiamente dicha. La hipótesis inicial de esta tesis fue que alcanzar un desarrollo temprano adecuado durante la gestación, lactancia, engorde y recría, con la ayuda de programas ajustados de alimentación en algunos de estos períodos, mejoraría el rendimiento reproductivo y la vida útil de los futuros conejos reproductores. Para evaluar esta hipótesis, se llevaron a cabo dos tipos de ensayos, tanto en conejos hembra de líneas maternas como en machos de líneas seleccionadas por velocidad de crecimiento y destinadas a la inseminación artificial. El primero de estos ensayos se centró en los diferentes patrones de crecimiento, desde el nacimiento hasta el final de la fase de recría, y su influencia en la carrera reproductiva y la vida útil del conejo. En el segundo tipo de pruebas, se evaluó el efecto del uso de diferentes dietas o programas de alimentación durante el período de recría en la productividad a corto y medio plazo. Los resultados muestran dos fases importantes en el desarrollo temprano, de acuerdo con sus efectos sobre el rendimiento reproductivo y la vida útil. Mostrar un mayor desarrollo corporal desde el nacimiento hasta los 63 días de vida parece tener una influencia positiva en el grado de madurez y la productividad al comienzo de su vida reproductiva, además de poder mejorar su supervivencia a corto plazo, pero con posibles efectos negativos en la esperanza de vida a largo plazo. Sin embargo, el desarrollo durante el período de recría (desde los 63 días de vida hasta el comienzo de la carrera reproductiva) parece tener un mayor impacto en la productividad y la esperanza de vida de nuestros futuros conejos reproductores. Las hembras más engrasadas en la primera inseminación tuvieron tamaños de camada más pequeños y un mayor riesgo de ser sacrificadas que las magras (P<0.05). Además, los machos que mostraron una mayor ganancia media diaria durante el período de recría tuvieron un número y porcentaje de eyaculados viables más bajos a lo largo de su vida productiva y mayor riesgo de muerte o sacrificio. Estos resultados podrían indicar que la clave para llevar a cabo un desarrollo adecuado durante el período de recría debería basarse tanto en conseguir que los conejos alcancen un grado de madurez apropiado, tanto fisiológica como reproductivamente, así como evitar un excesivo engrasamiento al inicio de su vida productiva. En los ensayos destinados a evaluar los programas de alimentación durante la recría, el uso de una restricción alimentaria en hembras, y especialmente el uso de dietas fibrosas (de 8.5 a 10 MJ ED/kg MS) permiten un desarrollo corporal gradual y adecuado a la edad de cubrición, con suficientes reservas corporales para afrontar el comienzo de la vida reproductiva y mejorando tanto su rendimiento reproductivo como su vida útil. El éxito de estos programas de alimentación de recría depende del momento y la duración de la aplicación de estos, mejorándose con la aplicación de un cambio a un pienso enriquecido energéticamente alrededor del primer apareamiento. En los machos, se observó que un programa de alimentación durante la recría adecuado debería adaptarse a la capacidad de ingesta de estos y a sus necesidades nutricionales en períodos concretos de la recría, consiguiendo así mejoras en algunos parámetros del semen al inicio de su vida reproductiva. En conclusión, tanto un desarrollo temprano adecuado desde la gestación hasta el comienzo de su vida reproductiva, como el uso de programas adecuados de alimentación durante la recría podrían mejorar significativamente el rendimiento reproductivo futuro, así como la esperanza de vida, tanto en conejos he / [CA] Qualsevol millora en el coneixement tant de la nutrició com del maneig dels futurs conills de criança ha de considerar-se com a prioritari en la producció de conills. No obstant açò, els principals esforços en investigació s'han centrat en aquests animals durant la fase de reproducció pròpiament dita. La hipòtesi inicial d'aquesta tesi va ser que aconseguir un desenvolupament primerenc adequat durant la gestació, lactància, engreix i criança, amb l'ajuda de programes ajustats d'alimentació en alguns d'aquests períodes, milloraria el rendiment reproductiu i la vida útil dels futurs conills reproductors. Per a avaluar aquesta hipòtesi, es van dur a terme dos tipus d'assajos, tant en conills femella de línies maternes, com en mascles de línies seleccionades per a la velocitat de creixement i destinades a la inseminació artificial. El primer d'aquests assajos es va centrar en els diferents patrons de creixement, des del naixement fins al final de la fase de criança, i la seua influència en la carrera reproductiva i la vida útil del conill. En el segon tipus de proves, es va avaluar l'efecte de l'ús de diferents dietes o programes d'alimentació durant el període de criança, en la productivitat a curt i mig termini. Els resultats obtinguts semblen indicar que podríem diferenciar dues fases en el desenvolupament primerenc, d'acord amb els seus efectes sobre el rendiment reproductiu i la vida útil. Mostrar un major desenvolupament corporal des del naixement fins als 63 dies de vida sembla tenir una influència positiva en el grau de maduresa i la productivitat al començament de la seua vida reproductiva, a més de poder millorar la seua supervivència a curt termini, però amb possibles efectes negatius en l'esperança de vida a llarg termini. No obstant açò, el desenvolupament durant el període de sembla tenir un major impacte en la productivitat i l'esperança de vida dels nostres futurs conills reproductors. Les femelles més greixades en la primera inseminació van tenir grandàries de ventrada més xicotets (tant nascuts com deslletats) i un major risc de ser sacrificades que les magres (P<0.05). A més, els mascles que van mostrar un major guany mitjà diari durant el període de criança van tenir un nombre i percentatge d'ejaculats viables més baixos al llarg de la seua vida productiva i major risc de mort o sacrifici. Aquests resultats podrien indicar que la clau per a dur a terme un desenvolupament adequat durant el període de criança hauria de basar-se tant a aconseguir que els conills aconseguisquen un grau de maduresa apropiat, per a afrontar els futurs desafiaments productius, com evitar un excessiu greixatge a l'inici de la seua vida productiva. En els assajos destinats a avaluar els programes d'alimentació durant la criança, l'ús d'una restricció alimentària en femelles, i especialment l'ús de dietes fibroses (de 8.5 a 10 MJ ED/kg MS) permeten un desenvolupament corporal gradual i adequat a l'edat de cobriment, amb suficients reserves corporals per a afrontar el començament de la vida reproductiva i millorant tant el seu rendiment reproductiu com la seua vida útil. L'èxit d'aquests programes d'alimentació de criança depèn del moment i la durada de l'aplicació d'aquests, millorant-se amb l'aplicació d'un canvi a un pinso enriquit energèticament al voltant del primer cobriment. En els mascles, es va observar que un programa d'alimentació durant la criança adequat hauria d'adaptar-se a la capacitat d'ingesta d'aquests i a les seues necessitats nutricionals en períodes concrets de la criança, aconseguint així millores en alguns paràmetres del semen a l'inici de la seua vida reproductiva. En conclusió, tant un desenvolupament primerenc adequat des de la gestació fins al començament de la seua vida reproductiva, com l'ús de programes adequats d'alimentació durant la criança podrien millorar significativament el rendiment reproductiu futur, així com l'esperança / [EN] Any improvement on the knowledge of both nutrition and management of the future rabbit breeders should be considered as crucial. However, main research efforts have been focused on animals during reproduction phase. The initial hypothesis of this thesis was that achieving an adequate early development during young rabbits' gestation, lactation, fattening and rearing, with the help of fitted feeding programmes in some of these periods, would be improved reproductive performance and lifespan of the future breeding rabbits. To evaluate this hypothesis, two types of trials, both in rabbit females from maternal lines selected for litter size at weaning and males from paternal lines selected for growth rate and intended on artificial insemination, were carried out. The first of these trials were mainly focused on the different growth patterns, from birth to the end of the rearing age, and their influence on rabbit's reproductive career and lifespan. In a second type of trials, the effect of the use of different diets or feeding programs during the rearing period in the performance in the short- medium-term was evaluated. The results obtained from the evaluation of the different growth patterns trials seem to indicate that, we could differentiate two parts on the early development according to their effects on reproductive performance and lifespan. To show a greater body development from birth to 63 days of life seems to have a positive influence on the maturity degree and productivity at the beginning of their reproductive life, as well as being able to improve their survival in the short-term, but it could be even negative for long-term lifespan. However, the development during the rearing period (from 63 days of life to the beginning of reproduction career) seems to have a higher impact on the productivity and lifespan of our rabbit breeders. Fatter rabbit females at first insemination had smaller litter sizes (born and weaned) and a higher risk of being culled (+13% per positive change in mm of perirenal fat) than lean ones (P<0.05). Also, rabbit males that showed a greater average daily gain during rearing period had a lower number and percentage of profitable ejaculates through it productive life (-10.1 and -4.9% per each 10 g of daily gain increase, respectively; P<0.05) and higher risk of death or culling (+16.2% per each increase in one standard deviation unit on live weight; P<0.05). These results could indicate that the key to carrying out an adequate development during the rearing period should allow the rabbits to reach an appropriate degree of physiological and reproductive maturity to face the future productive challenges, avoiding an excessive fatness at the beginning of their productive life. The use of a feeding restriction in rabbit females, and especially the use of fibrous diets (from 8.5 to 10 MJ DE/ kg DM) lead a gradual and adequate body development at mating, with enough body reserves to face the beginning of reproduction life and improving their whole reproductive performance and lifespan. The success of these rearing feeding programs depends in the moment and duration of application of them and improved with the application of a nutritional flushing around first mating. In rabbit males, it was observed that an adequate rearing feeding program should adapt it to the male's intake capacity and their nutritional requirements rearing period, especially to their high DP needs at the beginning of rearing period or when their requirements were close to maintenance, to improve some semen parameters at the beginning of their reproduction life. In conclusion, both the adequate early development of future rabbit breeders, from their own gestation to the beginning of their reproductive life, and the use of appropriate rearing feeding programs could significantly improve their future reproductive performance, as well as their life expectancy, both in rabbit females and males. / Martínez Paredes, EM. (2019). Rearing programmes for breeding rabbits. Effect of early development and feeding on future reproductive performance of rabbit females and males [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/124969 / Compendio

The mallard (Anas platyrhynchos) is the most numerous and widespread duck in the northern hemisphere and a model species in ecology and harvest management. Migration is a crucial life stage for many birds and understanding the drivers of migration has important implications for conservation biology and assessment of animal population responses to global changes. Furthermore, mallard migration is a fundamental determinant of the epidemiology of many diseases of major relevance for both animal and human health. For example, it is the reservoir host for influenza A viruses (IAV), a widespread zoonosis causing mortality and economic damage. Improved knowledge of mallard behaviour during migration and the impacts of infection in mallards is needed to determine the role of wild birds in global IAV dynamics. This thesis focuses on mallard stopover ecology, an explicitly important part of the annual life cycle that is not well understood. The study area was southern Öland, SE Sweden, where mallard stopover behaviour was scrutinized by a combination of telemetry and ringing data analyses. Specifically, habitat preferences, movements, and emigration decisions were studied in-depth. Potential effects of low pathogenic avian influenza (LPAIV) infection on movement parameters were also investigated. Radio-tracking revealed that stopover mallards adhered to a strict diel pattern, in which they spent the days resting along the coast, visited crop fields at dawn and dusk, and foraged on inland water bodies during the darkest night hours. Notably, the importance of residual maize, as well as small ephemeral wetlands on the unique alvar steppe habitat that predominates on Öland, was previously unknown. LPAIV infection status did not affect movement behaviour, highlighting the possible risk of spread of IAV from wild mallards to poultry along the migratory flyway. Through capture-mark-recapture modelling, it was confirmed that weather, particularly wind direction, was the most important determinant of departure from the stopover site. In contrast, the body condition of departing mallards was less crucial. Taken together, the research presented in this thesis contributes to improved knowledge about mallard stopover ecology and its role in LPAIV disease dynamics.