Thesis (MPhil (Animal Sciences. Livestock Management))--University of Stellenbosch, 2009. / ENGLISH ABSTRACT: Information from 200 randomly selected egg project beneficiaries was obtain during 2008 to evaluate the impact of managerial factors on the sustainability of poverty alleviation egg laying projects in the Vhembe district, with special reference to the three municipalities (Mutale, Makhado, and Thulamela). A high proportion (80%) of the beneficiaries was poor rural women. The majority of these beneficiaries are old and illiterate. A high proportion of the beneficiary households is composed of extended families and headed by unemployed women. The majority of beneficiaries are sole breadwinners. The majority relies on agriculture and social grants as a source of income. All the beneficiaries indicated that the project increased the household income as a result of the revenue collected from the sale of eggs. From the study, 96% of the projects were initiated by Government, while only 3.52% were initiated by the beneficiaries themselves. A very high proportion of the beneficiaries (88.94%) was not given any opportunity to decide about the type of the project they were interested in. This also included a high proportion (60.61%) of beneficiaries who indicated they were not interested in starting an egg laying project. A high proportion of beneficiaries (60.71%) were not satisfied with the project, and 51.52% indicated is because of lack of funds and the remainder been because of lack of support from the government. A proportion (53.77%) of beneficiaries indicated that they are visited only once a week by extension officers. A high proportion of the beneficiaries (73.23%) rated the support that they get from the extension officers as poor. A high proportion of the beneficiaries received 36 layers, and only 3.02% were having more than 36 layers. About 69.35% of the beneficiaries didn’t know the causes of mortalities of their layers. This also confirmed the high proportion (65.85%) of beneficiaries who indicated that they were not trained to identify and treat diseases. About 73.87% of the beneficiaries rated the performance of the project as good. About 53.27% of the beneficiaries indicated that the project can sustain itself. A proportion of beneficiaries (52.76%) indicated the sustainability indicator as good market of the products. / AFRIKAANSE OPSOMMING: Inligting van 200 lukraak geselekteerde eierprojek begunstigdes is tydens 2008 ingesamel, met die doel om die invloed van bestuursfaktore op die volhoubaarheid van armoede verligtings eierproduksie projekte in die Vhembe distrik, met spesiale verwysing na die drie munisipaliteite Mutale, Makhado en Thulamela. ‘n Groot proporsie (80%) van die begunstigdes was arm landelike vroue. Die meerderheid van hierdie vroue was oud en ook ongeskool. ‘n Groot proporsie van die begunstigde huishoudings bestaan uit direkte en verlangse familielede, met dié huishoudings wat werklose vrouens as familiehoofde het. Die meerderheid van die begunstigdes is ook die alleen broodwinners. Die meerderheid van die huishoudings maak staat op landbou en welsyn toekennings as ‘n bron van inkomste. Al die begunstigdes ht aangedui dat huishoudelike inkomste toegeneem het as gevolg van die verkoop van eiers geproduseer in die projekte. In die studie was 96% van die projekte deur die Regering geïnisieer, terwyl 3.52% van die projekte deur die begunstigdes self geïnisieer is. ‘n Groot proporsie van die begunstigdes (88.94%) was nie die geleentheid gegun om ‘n keuse te kan uitoefen oor die projek wat hulle wil doen nie. Hierdie laasgenoemde proporsie het ook die begunstigdes (60.61%) ingesluit wat aangedui het dat hulle nie in eierlê projekte belanggestel het nie. ‘n Groot proporsie van die begunstigdes (60.71%) was ontevrede met die projek, met 51.52% van hierdie groep wat dit aan ‘n tekort van fondse toegeskryf het. Die oorblywende 9.19% het dit aan ‘n gebrek van ondersteuning vanaf die Regering se kant toegeskryf. ‘n Proporsie van die begunstigdes (53.77%) het aangedui dat hulle een keer per week deur ‘n voorligtingsbeampte besoek word. ‘n Groot proporsie (73.23%) het die kwaliteit van ondersteuning deur die voorligtingsbeamptes as swak beoordeel. ‘n Groot proporsie van die begunstigdes het 36 lêhenne ontvang, met slegs 3.02% wat meer as 36 lêhenne ontvang het.Ongeveer 69.35% van die begunstigdes was onseker oor die redes vir die afsterwe van hulle lêhenne. Dit ondersteun die groot proporsie (65.85%) van die begunstigdes wat aangedui het dat hulle geen opleiding om siektes te kan identifiseer en te behandel, ontvang het nie. Ongeveer 73.87% van die begunstigdes het die projek as goed gereken, met 53.27% wat gevoel het die projek kan ditself onderhou. ‘n Proporsie (52.76%) van die begunstigdes het die bemarkingswaarde van hulle produk as ‘n volhoubaarheidsindikator beskou.

A utilização de enzimas como aditivos alimentares para poedeiras comerciais pode aumentar a digestibilidade dos nutrientes dos ingredientes da dieta. Assim, o objetivo do trabalho foi avaliar os efeitos da suplementação de enzima xilanase em dietas de poedeiras comerciais à base de milho e soja sobre desempenho, morfologia intestinal e incremento de energia da dieta. Foram utilizadas 400 poedeiras da linhagem Hy-line, variedade W36 com duas semanas de idade submetidas às dietas experimentais até as 80 semanas de idade. As aves foram distribuídas em delineamento inteiramente casualisado em esquema fatorial 2x2 (nível de energia x inclusão de xilanase), totalizando 4 tratamentos com 10 repetições de 10 aves cada. Os tratamentos foram: controle positivo (dieta balanceada para respectiva idade); controle positivo+xilanase; controle negativo (dieta com redução de 100 kcal/kg no nível de EM); controle negativo+xilanase. Nas fases de cria e recria (2 a 6 e 7 a 17 semanas), foram realizadas as avaliações para peso corporal, ganho de peso, consumo de ração, conversão alimentar, viabilidade criatória e uniformidade do lote. As seis e 16 semanas foram colhidos fragmentos de intestino das porções duodeno, jejuno e íleo para mensurações de altura de vilo e profundidade de cripta. Durante a fase de postura (18 a 80 semanas) foram avaliadas características de desempenho (ganho de peso, consumo de ração, produção, peso e massa de ovos, conversão alimentar e viabilidade criatória). Foram realizados ainda, quatro ensaios de digestibilidade (14, 36, 60 e 80 semanas) para determinação da energia metabolizável aparente e energia metabolizável aparente corrigida das dietas e coeficientes de metabolizabilidade dos nutrientes. Conclui-se que a suplementação de xilanase em dietas de poedeiras com redução de 100 kcal/kg de energia metabolizável promove melhor formação da mucosa intestinal e o fornecimento de dietas com níveis de energia adequados associadas à suplementação de xilanase proporciona valores de energia metabolizável (EMA) e energia metabolizável corrigida (EMAn) superiores em relação aos valores obtidos com dietas sem suplementação de enzima para fase de postura. Além disso, a adição de xilanase em dietas de poedeiras comerciais, a base de milho e soja possibilita a redução do nível de energia da dieta sem prejudicar o desempenho das aves. / The use of enzymes as feed additives for laying hens can increase the digestibility of nutrients present in diet. Thus, the objective was to evaluate the effects of xylanase enzyme supplementation in diets of laying hens based corn and soybean on performance, gut morphology and increased energy diet. Were used 400 layers of Hy-line W36 with two weeks of age fed experimental diets until 80 weeks of age. The birds were distributed to a completely randomized design in a 2x2 factorial (including energy level x xylanase), totaling four treatments with 10 replicates of 10 birds each. The treatments were: positive control (balanced diet to the age), positive control + xylanase, negative control (diet with a reduction of 100 kcal/kg ME) and negative control + xylanase. In phase of rearing (2 to 6 and 7 to 17 weeks), evaluations were made for body weight, weight gain, feed intake, feed conversion, livability and uniformity. At six and 16 weeks were collected fragments intestine of portions duodenum, jejunum and ileum for measurement of villus height and crypt depth. During the laying phase (18 to 80 weeks) were evaluated performance characteristics (weight gain, feed intake, production, weight and egg mass, feed conversion and livability). Were also conducted four assays of digestibility (14, 36, 60 and 80 weeks) to determine the apparent metabolizable energy and apparent metabolizable energy corrected, coefficients of metabolization of diet nutrients. It was concluded that supplementation xylanase in diets of laying hens with reduction of 100 kcal/kg of metabolizable energy promotes better formation of the intestinal mucosa and compensates for the reduction of dietary energy, providing metabolizable energy and feeding diets with energy levels associated with adequate supplementation of xylanase provide values metabolizable energy and corrected metabolizable energy above to the values obtained with diets without supplementation enzyme to the production phase. Furthermore, the addition of xylanase in diets for laying hens, based corn and soybeans, allows reduction in the level of dietary energy without damaging the performance of birds.

O objetivo dessa pesquisa foi avaliar o efeito do uso de enriquecimento ambiental em gaiolas convencionais de galinhas poedeiras alojadas em diferentes densidades. A parte experimental deste estudo foi dividida em três capítulos. No capítulo três foi registrada a porcentagem de produção dos ovos, de mortalidade, e monitoradas a temperatura do ar seco (°C) e a umidade relativa do ar (%), calculando-se assim a entalpia específica (kJ.kg-1 de ar seco). No quarto capítulo são exibidos os resultados da qualidade dos ovos baseados em avaliações externas e internas do produto, conforme as seguintes variáveis: Peso do ovo (g), gravidade específica (g.ml-1), unidade Haugh, índice de gema, resistência de casca, espessura de casca, porcentagem de casca, porcentagem de gema, porcentagem de albúmen, porcentagem de ovos com manchas de carne na gema e no albúmen, manchas de sangue na gema, porcentagem de ovos rachados, quebrados, sujos, pouco sujos, limpos e anormais. No quinto capítulo foi avaliado o comportamento e a performance física das aves por meio de análises da condição da plumagem, do coxim plantar, do esterno e da crista. O delineamento experimental foi inteiramente casualizado em esquema fatorial 3 x 3, ou seja, 3 tipos de enriquecimento ambiental e 3 tipos de densidades de alojamento, gerando-se assim 9 tratamentos, sendo eles: T1 (450 cm2/ave + cordas), T2 (750 cm2/ave + cordas), T3 (1125 cm2/ave + cordas), T4 (450 cm2/ave + cortinas), T5 (750 cm2/ave + cortinas), T6 (1125 cm2/ave + cortinas), T7 (450 cm2/ave + sem enriquecimento), T8 (750 cm2/ave + sem enriquecimento), T9 (1125 cm2/ave + sem enriquecimento). Os resultados evidenciaram que o uso de enriquecimento ambiental e diferentes densidades de animais/gaiola não tiveram influência significativa na mortalidade e na produção de ovos de galinhas poedeiras na tipologia da instalação estudada. Além disso, o efeito da inserção de enriquecimento ambiental na integridade física das aves variou conforme a densidade de alojamento e contribuiu positivamente na saúde dos pés e na integridade das penas. Tratamentos com alta densidade de alojamento, ou seja, com 5 aves/gaiola, causam supressão do comportamento, aumentam a agressividade e diminuem o acesso da ave aos recursos disponíveis na gaiola. Os dados evidenciaram que a utilização de enriquecimento ambiental e menores densidades de alojamento exerceram efeito positivo na qualidade externa dos ovos e diminuíram a incidência de partículas estranhas neste produto, melhorando-o visualmente e diminuindo as suas perdas. Conclui-se que a inserção de enriquecimento ambiental é uma importante ferramenta para melhorar as condições de bem-estar e a qualidade dos ovos de galinhas poedeiras e este efeito pode variar em função de diferentes densidades de alojamento. / The objective of this research was to evaluate the effect of the use of environmental enrichment in conventional cages for laying hens housed in different stocking densities. The experimental part of this study was divided into three sections. At third chapter was recorded the percentage of production of eggs, mortality, and monitored the temperature of the dry air (°C) and relative humidity (%), calculating thus the specific enthalpy (kJ.kg-1 air dry). In the fourth chapter are shown the results of the egg quality based on external and internal evaluation of the product, according to the following variables: egg weight (g), specific gravity (g.ml-1), Haugh unit, yolk index, shell strength, shell thickness, shell percentage, yolk percentage, albumen percentage, percentage of eggs with meat spots in the yolk and albumen, blood spots on the yolk, percentage of cracked eggs, broken eggs, dirty eggs, dirty little eggs, clean and abnormal eggs. In the fifth chapter was analyzed the bahaviour and the physical performance of birds through the plumage condition, the footpad condition, the sternum and the comb condition. The experimental design was completely randomized in a factorial 3 x 3 (3 types of environmental enrichment and 3 types of stocking densities). It generated 9 treatments, as follows: T1 (450 cm2/bird + strings), T2 (750 cm2/bird + strings), T3 (1125 cm2/bird + strings), T4 (450 cm2/bird + curtains), T5 (750 cm2/bird + curtains), T6 (1125 cm2/bird + curtains), T7 (450 cm2/bird + without enrichment), T8 (750 cm2/bird + without enrichment), T9 (1125 cm2/bird + without enrichment). The results showed that the use of environmental enrichment and different stocking densities of animals/cage had no significant influence on mortality and production of laying hens in the typology of the studied installation. Moreover, the effect of environmental enrichment on the physical integrity of birds varied according to the stocking density and contributes positively to the health of the feet and integrity of plumage. Treatments with high density, i.e., with 5 animals/cage, causing suppression of behavior, increased aggression and decrease the bird\'s access to resources available in the cage. The data show that the types of environmental enrichment and lower stocking densities had a positive effect on the external quality of eggs and decreased the incidence of foreign particles in this product, improving it visually and reducing their losses. It is concluded that environmental enrichment insertion is an important tool to improve the welfare and egg quality of laying hens and this effect may vary according to different stocking densities.

<p>The purpose of gene mapping is to understand the underlying genetics of simple and complex traits like plumage colour and growth. This thesis is based on a cross between the wild ancestor of the modern chicken, the red junglefowl, and a White Leghorn line selected for high egg mass. There are obvious phenotypic differences between these two breeds in several aspects such as growth, egg production and behaviour. These complex traits are often influenced by a number of genes or Quantitative Trait Loci (QTL) as well as environmental factors.</p><p>Identification of QTL regions involves testing of association between genetic markers and the phenotype of interest. The QTL identified in this study explain most of the difference in adult body weight between the red junglefowl and the White Leghorn, but less of the difference at earlier age. By applying a different method for detection of QTL, including gene interactions, epistasis, we can understand more of the genetics behind early growth. The allele coming from the red junglefowl is generally associated with lower weight, egg production and food consumption.</p><p>In this study we have also identified two genes explaining the difference in plumage colour in the cross. The <i>Extension</i> locus, encoded by the melanocortin receptor 1 (<i>MC1R</i>), controls the amount of pigment produced has shown to be associated with plumage colour. A mutation in the <i>MC1R</i> gene causes black pigmentation of the plumage. </p><p>We have also found association between the <i>PMEL17</i> gene, known to be involved in normal pigmentation, and the <i>Dominant white</i> phenotype present in the White Leghorn. After comparison of sequences from different alleles at the <i>Dominant white</i> locus, amino acid alteration caused by insertion and deletion in the transmembrane region of the <i>PMEL17</i> protein has been revealed. These mutations are associated with alleles representing different plumage colour variants.</p>

The purpose of gene mapping is to understand the underlying genetics of simple and complex traits like plumage colour and growth. This thesis is based on a cross between the wild ancestor of the modern chicken, the red junglefowl, and a White Leghorn line selected for high egg mass. There are obvious phenotypic differences between these two breeds in several aspects such as growth, egg production and behaviour. These complex traits are often influenced by a number of genes or Quantitative Trait Loci (QTL) as well as environmental factors. Identification of QTL regions involves testing of association between genetic markers and the phenotype of interest. The QTL identified in this study explain most of the difference in adult body weight between the red junglefowl and the White Leghorn, but less of the difference at earlier age. By applying a different method for detection of QTL, including gene interactions, epistasis, we can understand more of the genetics behind early growth. The allele coming from the red junglefowl is generally associated with lower weight, egg production and food consumption. In this study we have also identified two genes explaining the difference in plumage colour in the cross. The Extension locus, encoded by the melanocortin receptor 1 (MC1R), controls the amount of pigment produced has shown to be associated with plumage colour. A mutation in the MC1R gene causes black pigmentation of the plumage. We have also found association between the PMEL17 gene, known to be involved in normal pigmentation, and the Dominant white phenotype present in the White Leghorn. After comparison of sequences from different alleles at the Dominant white locus, amino acid alteration caused by insertion and deletion in the transmembrane region of the PMEL17 protein has been revealed. These mutations are associated with alleles representing different plumage colour variants.

Στην παρούσα εργασία πραγματοποιήθηκε εκτίμηση της αναπαραγόμενης βιομάζας του ευρωπαϊκού γαύρου, Engraulis encrasicolus, στην περιοχή του Βορειοανατολικού Αιγαίου (Θρακικό Πέλαγος, Κόλπος Καβάλας, Στρυμωνικός Κόλπος, Λήμνος) τα έτη 2003 και 2004 με τη Μέθοδο Ημερήσιας Παραγωγής Αβγών (DEPM). Για την εφαρμογή της μεθόδου πραγματοποιήθηκαν δύο ωκεανογραφικά ταξίδια με το Ε/Σ «ΦΙΛΙΑ» κατά το μέγιστο της ωοτοκίας του γαύρου τον Ιούνιο του 2003 και του 2004. Στη διάρκεια τους συλλέχθηκαν δείγματα ιχθυοπλαγκτού για την εκτίμηση της ημερήσιας παραγωγής αβγών, ενώ πραγματοποιήθηκαν και λήψεις κατακόρυφων διατομών θερμοκρασίας και αλατότητας σε εκτεταμένο δίκτυο σταθμών. Παράλληλα, πραγματοποιήθηκαν δειγματοληψίες ενήλικων ατόμων γαύρου είτε επί του επαγγελματικού στόλου των γρι-γρι της περιοχής, είτε με την πελαγική τράτα του «ΦΙΛΙΑ», τα οποία χρησιμοποιήθηκαν για την εκτίμηση της αναλογίας φύλου, της γονιμότητας ομάδας, της συχνότητας ωοτοκίας και του μέσου βάρους των θηλυκών. Όσον αφορά στις περιβαλλοντικές συνθήκες, το 2003 παρατηρήθηκε αυξημένη στρωματοποίηση των υδάτων, χαμηλότερη επιφανειακή αλατότητα και υψηλότερες τιμές χλωροφύλλης-α, διαφορές που πιθανώς οφείλονται σε αυξημένη εκροή νερού της Μαύρης Θάλασσας. Και τα δύο έτη η βιομάζα του ζωοπλαγκτού ήταν περίπου ίδια. Μέσω απλής ανάλυσης πηλίκου για το χαρακτηρισμό του αναπαραγωγικού ενδιαιτήματος του γαύρου, βρέθηκε ότι και τις δύο χρονιές η ωοτοκία πραγματοποιήθηκε σε νερά με χαμηλή αλατότητα (<34.5), πλούσια σε χλωροφύλλη-α και ζωοπλαγκτό. Αντίθετα, τα θερμοκρασιακά εύρη κατά τις δύο χρονιές διέφεραν, γεγονός που φαίνεται να αντανακλά περισσότερο τις διαφορές θερμοκρασίας ανάμεσα στα δύο έτη παρά διαφορετική προτίμηση για ωοτοκία. Επιπλέον, το 2004 η παραγωγή αβγών ήταν μειωμένη, το πεδίο αναπαραγωγής είχε συρρικνωθεί και η ωοτοκία ήταν επικεντρωμένη στην περιοχή του Θρακικού. Για την εκτίμηση της συχνότητας ωοτοκίας πραγματοποιήθηκε ιστολογική ανάλυση των θηλυκών γονάδων του γαύρου, από την οποία προέκυψε ότι ενώ τα στάδια ανάπτυξης των υγιών ωοκυττάρων ήταν παρόμοια με περιγραφές για το είδος Engraulis mordax, τα στάδια της ατρησίας παρουσίασαν ορισμένες διαφορές. Αυτές αφορούσαν στην εμφάνιση καφε-κίτρινων χρωστικών (χαρακτηριστικό γνώρισμα της δ-ατρησίας) στο τέλος της β-ατρησίας. Επιπλέον, η απορρόφηση των κενών ωοθυλακίων διαρκούσε δύο ημέρες σε αντίθεση με παρατηρήσεις για το Engraulis mordax, όπου παρατηρούνταν και κενά ωοθυλάκια τριών ημερών, διαφορά που οφείλεται στις υψηλότερες θερμοκρασίες του ΒΑ. Αιγαίου σε σχέση με περιοχές αναβλύσεων. Οι παράμετροι των ενηλίκων που προέρχονταν από δείγματα της επαγγελματικής και πειραματικής αλιείας δεν εμφάνισαν σημαντικές διαφορές μεταξύ τους. Αντίθετα, διαφορές παρατηρήθηκαν ανάμεσα στα δύο έτη όσον αφορά στις παραμέτρους του μέσου βάρους, της συχνότητας ωοτοκίας και της γονιμότητας. Συγκεκριμένα, το 2004 τα ψάρια ήταν βαρύτερα, πιο εύρωστα και απελευθέρωναν μεγαλύτερο αριθμό αβγών ανά μικρότερα χρονικά διαστήματα. Αν λάβει κανείς υπ’όψιν ότι το 2004 η αναπαραγόμενη βιομάζα ήταν σημαντικά μικρότερη ενώ η βιομάζα του ζωοπλαγκτού παρέμεινε η ίδια, οι παραπάνω διαφορές μπορούν να εξηγηθούν από φαινόμενα εξάρτησης των παραμέτρων αυτών από την πυκνότητα του πληθυσμού (density dependence). Η αναπαραγόμενη βιομάζα το 2004 (6251t) ήταν σημαντικά μειωμένη και αντιστοιχούσε σχεδόν στο 1/3 της βιομάζας του 2003 (17600t). Η μείωση αυτή πιθανώς να οφείλεται σε συνδυασμό έντονης αλιευτικής πίεσης και χαμηλών επιπέδων στρατολόγησης της ηλικιακής κλάσης του 2003. / The spawning biomass of the European anchovy, Engraulis encrasicolus, stock in the N.E. Aegean Sea was estimated by means of the Daily Egg Production Method (DEPM) for the years 2003 and 2004. Two oceanographic surveys were conducted with the R/V “PHILIA” during the maximum reproductive activity of the anchovy population in June 2003 and 2004. Ichthyoplankton sampling and vertical profiles of temperature and salinity were performed over an extensive grid of stations. At the same time adult anchovy samples were collected either on board the commercial purse-seine fleet or by means of an experimental pelagic trawl operated by “PHILIA”. The adult samples were used to estimate parameters of the DEPM: sex ratio, mean female weight, batch fecundity and spawning frequency. Significant interannual differences were found in the environmental conditions. In June 2003 the water column was more stratified, less saline (5m) and richer in chlorophyll-α, which probably were due to larger outflow of Black Sea Water (BSW). The zooplankton biomass remained the same during 2003 and 2004. A simple quotient rule analysis was applied to characterize the spawning habitat of anchovy. In both years anchovy spawning appeared to take place in less saline waters (34.5), rich in chlorophyll-α and zooplankton. On the contrary, anchovy spawning appeared to take place over different temperature range in the two years. This rather reflects different temperature values in 2003 and 2004 than different selection for spawning. In 2004 the daily egg production was reduced, the spawning area was limited and the spawning activity took place mainly in the Thracian Sea. Histological analysis of the female anchovy gonads was carried out in order to estimate the spawning frequency. The developmental stages of healthy oocytes were similar to those of the species Engraulis mordax. However, the atresia stages were different with regard to the appearance of brown-yellow pigments at the end of beta stage atresia instead of the end of delta stage atresia. Moreover, the absorption of the postovulatory follicle lasted two days instead of three days. The higher temperatures in the N.E. Aegean Sea were responsible for the shorter duration of the postovulatory follicle absorption. There were no statistically significant differences between DEPM adult parameters calculated from purse-seine samples compared to pelagic trawl samples. On the contrary, mean female weight, fecundity and spawning frequency showed statistically significant differences between the two years. In 2004 the anchovies were in better condition and produced numerous eggs in short interspawning intervals. Since the estimated biomass was lower in 2004 while the zooplankton biomass remained stable, it seems that density-dependence phenomena could justify the interannual differences. The estimated spawning biomass in 2004 (6251t) was significantly lower compared to that of 2003 (17600t). Intense fishing effort and low levels of recruitment of the 2003 cohort are probably responsible for this decrease.

Made available in DSpace on 2014-06-11T19:26:07Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-02-19Bitstream added on 2014-06-13T20:54:08Z : No. of bitstreams: 1 savegnago_rp_me_jabo.pdf: 1186672 bytes, checksum: ecac87cb07ef42be339beaa3ed971737 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Modelos não lineares são úteis para ajustar curvas de produção de ovos de aves, facilitando o estudo do desempenho dessa característica ao longo do tempo. As estimativas de parâmetros genéticos da produção de ovos e de outras características associadas auxiliam no processo de seleção. O objetivo do trabalho foi: (1) utilizar modelos não lineares para ajustar curvas de produção de ovos aos dados de uma população de aves selecionada para postura e uma controle e verificar as mudanças ocorridas entre estas curvas preditas em função do processo de seleção, por meio do ganho genético e pelas diferenças entre as estimativas dos parâmetros dos modelos; (2) estimar parâmetros genéticos para características relacionadas à postura de ovos da população selecionada, avaliar a associação genética entre estas e determinar quais as melhores características que podem ser utilizadas para melhorar a produção de ovos. Foram estudados os ajustes de 10 modelos não lineares aplicados aos registros da produção de ovos de 54 semanas de postura de 1693 aves de uma população selecionada para taxa de postura e 282 aves de uma população controle. Foi utilizado o PROC NLIN do SAS com o algoritmo de Gauss-Newton para efetuar os ajustes dos modelos. Os parâmetros genéticos, considerando 1289 aves da linhagem selecionada, foram estimados pelo método da máxima verossimilhança restrita, utilizando modelo animal que incluiu o efeito fixo de incubação e os efeitos aleatórios genético aditivo e residual. As características estudadas foram relação altura-largura e peso dos ovos às 32, 37 e 40 semanas de idade (REL32, REL37, REL40, PO32, PO37 e PO40, respectivamente), peso corporal às 54 e 62 semanas (PC54 e PC62), idade à maturidade sexual (IMS), taxa de postura nos períodos parciais de 17 a 30 e 17 a 40 semanas (P1730 e P1740), taxa de postura nos períodos residuais de... / Nonlinear models are useful to adjust egg production curves to study the performance of this trait over the time. Estimates of genetic parameters for egg production and other associated traits help in the selection process. The aim of this study were: (1) use nonlinear models to fit curves of egg production data from a population of birds selected for laying and its respective control and describe the changes between these predicted curves through the genetic gain and differences between the estimates of parameters, resulting by the selection process; (2) to estimate genetic parameters for traits related to egg-laying of the selected population to evaluate the genetic association between them and determine what traits can be used to improve the egg production. Ten non-linear models have been used to adjust the record of egg production of 1693 laying hens of the selected population and 282 hens of the control population in 54 weeks of egg production. The SAS PROC NLIN with the Gauss-Newton algorithm has been used to make the adjustments of the models. Genetic parameters for 1289 selected hens were estimated by restricted maximum likehood using an animal model that included fixed effects of incubation and random additive genetic and residual effects. The traits in this study were the relation between height-width of the egg and egg weight at 32, 37 and 40 weeks of age (HW32, HW37, HW40, EW32, EW37 and EW40, respectively), body weight at 54 and 62 weeks (BW54 and BW62), age at first egg (AFE), the egg production in 17 to 30 and 17 to 40 weeks (P1730 and P1740), in 30 to 70 and 40 to 70 weeks (P3070 and P4070) and the total egg production (TEP). Two multivariate analyses were made: a k-means clustering method to describe patterns of egg and poultry and principal components with the breeding values (BV). There were differences between the parameters of egg production curves in the selected ... (Complete abstract click electronic access below)

Made available in DSpace on 2015-03-26T13:42:20Z (GMT). No. of bitstreams: 1 texto completo.pdf: 726201 bytes, checksum: 74d4f315d608a52cd33e55e848a74abd (MD5) Previous issue date: 2010-07-23 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The objective of this study was to estimate genetic and phenotypic parameters for egg production and egg mass in meat-type quails and to propose an optimal age for selection of meat-type quails through egg production and egg mass ratio. The data used for this study came from 3.503 female meat-type quails, (UFV1: 1.811 quails; UFV2: 1.692 quails) of the Breeding Program for Poultry, at Federal University of Viçosa. Laying was assessed by the number of eggs produced from the 42th day of life on. For the study on egg production, the traits analyzed were: partial periods of egg production until 77 days (N77), 112 days (N112), 147 days (N147), 182 days (N182) and total production period of 407 days (N407) through the use of a single and bi-trait animal model. For the study on egg mass, the characteristics analyzed were: egg mass in partial periods until 77 days (M77), 112 days (M112), 147 days (M147), 182 days (M182), and egg mass in the total period of 407 days (M407). To analyze the efficiency of selection in each partial period, in relation to the total period, it was used the relative efficiency. For the egg production trait, considering the genetic group UFV1, heritability for N77, N112, N147, N182 and N407 were 0.03, 0.06, 0.07, 0.08, and 0.16, respectively. The estimate of genetic correlation was higher between N112 and N407 (0.64). For other partial periods (N77xN407, and N147xN407 N182xN407), the values of genetic correlation ranged from 0.34 to 0.49. For the genetic group UFV2, the heritabilities for N77, N112, N147, N182 and N407 were, respectively, 0.20, 0.23, 0.25, 0.25, and 0.22. The correlation between each partial period with the total period presented median values ranging from 0.44 to 0.47. The relative efficiency for both genetic groups did not exceed the unity. The highest value found for the genetic group UFV1 was 0.4 during the period N112. For the genetic group UFV2, the highest relative efficiency was 0.49 for the periods N147 and N182. Considering the trait egg mass, the genetic group UFV1 obtained heritability values equal to 0.58 (M77), 0.59 (M112), 0.57 (M147), 0.59 (M182) and 0.24 (M407 ). The values for genetic correlations were medium, ranging from 0.51 (M77xM407) to 0.61 (M112xM407, M147xM407). For the genetic group UFV2, the heritabilities were of low magnitude: 0.05 (M77), 0.03 (M112), 0.04 (M147), 0.05 (M182) and 0.11 (M407). The values for genetic correlation ranged from 0.61 (M112xM407) to 0.93 (M77xM407). The highest relative efficiency value (0.96) was found during the period M112, to the genetic group UFV1, and 0.62 in the period M77 to the genetic group UFV2. Thus, the partial periods for egg production would be important to assist in the selection of meat-type quails, but the selection would be more efficient considering the total production. However, the use of selection through the mass of eggs until 112 days would be particularly interesting for genetic group UFV1, because the efficiency was close to the unity and the generation interval would be greatly reduced. For the group UFV2, even if it has presented low values of relative efficiency, it would only benefit from the reduction in generation interval for selection through the mass of eggs in the partial period until 77 days because it would allow three generations per year. / Objetivou-se nesse trabalho estimar parâmetros genéticos e fenotípicos para produção de ovos e massa de ovos em codornas de corte e propor uma idade ideal para seleção de codornas de corte através da produção de ovos e massa de ovos. Os dados utilizados para esse estudo são provenientes de 3503 codornas de corte, sendo 1811 fêmeas UFV1 e 1692 fêmeas UFV2, pertencentes ao Programa de Melhoramento Genético de Aves da Universidade Federal de Viçosa. A postura foi avaliada por meio do número de ovos a partir do 42º dia de vida. Para o estudo sobre produção de ovos, as características analisadas foram períodos parciais de produção de ovos até 77 dias (N77), até 112 dias (N112), até 147 dias (N147), até 182 dias (N182) e período de produção total até 407 dias (N407), através do modelo animal uni e bicaracterístico. Para o estudo sobre massa de ovos, as características analisadas foram massa de ovos em períodos parciais até 77 dias (M77), até 112 dias (M112), até 147 dias (M147), até 182 dias (M182) e massa de ovos no período total, até 407 dias (M407). Para analisar a eficiência de seleção em cada período parcial em relação ao período total, foi utilizada a eficiência relativa. Para a característica produção de ovos, considerando o grupo genético UFV1, as herdabilidades para N77, N112, N147, N182 e N407 foram respectivamente, 0,03, 0,06, 0,07, 0,08 e 0,16. A estimativa de correlação genética mais alta foi entre N112 e N407 (0,64). Para os outros períodos parciais (N77xN407, N147xN407 e N182xN407), os valores de correlação genética variaram de 0,34 a 0,49. Para o grupo genético UFV2, as estimativas de herdabilidades para N77, N112, N147, N182 e N407 foram respectivamente, 0,20, 0,23, 0,25, 0,25 e 0,22. A correlação genética entre cada período parcial com o período total apresentou valores medianos variando de 0,44 a 0,47. A eficiência relativa para ambos os grupos genéticos não ultrapassaram a unidade. O maior valor encontrado para o grupo genético UFV1 foi de 0,4 no período parcial N112. Para o grupo genético UFV2, o maior valor de eficiência relativa foi de 0,49 para os períodos parciais N147 e N182. Considerando a característica massa de ovos, o grupo genético UFV1 obteve valores de herdabilidade iguais a 0,58 (M77), 0,59 (M112), 0,57 (M147), 0,59 (M182) e 0,24 (M407). Os valores de correlação genética foram medianos, variando de 0,51 (M77xM407) a 0,61 (M112xM407, M147xM407). Para o grupo genético UFV2, as estimativas de herdabilidades foram de baixa magnitude sendo 0,05 (M77), 0,03 (M112), 0,04 (M147), 0,05 (M182) e 0,11 (M407). Os valores de correlação genética variaram de 0,61 (M112xM407) a 0,93 (M77xM407). O maior valor de eficiência relativa encontrado foi de 0,96 no período parcial M112, para o grupo genético UFV1 e 0,62 no período parcial M77, para o grupo genético UFV2. Desta forma, os períodos parciais para produção de ovos seriam importantes para auxiliar no processo de seleção de codornas de corte, mas a seleção seria mais eficiente considerando a produção total. Entretanto, o uso da seleção através da massa de ovos até 112 dias seria particularmente interessante para o grupo genético UFV1, pois a eficiência foi próxima da unidade e o intervalo de geração seria bastante reduzido. Para o grupo genético UFV2, mesmo que tenha apresentado valores de eficiência relativa baixos, se beneficiaria apenas da redução no intervalo de geração para a seleção através da massa de ovos no período parcial até 77 dias, pois possibilitaria três gerações por ano.

Made available in DSpace on 2015-03-26T13:54:41Z (GMT). No. of bitstreams: 1 texto completo.pdf: 335647 bytes, checksum: 48f83f48f24498bb0bccf1a1ea2a5dcc (MD5) Previous issue date: 2008-07-28 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / There were two experiments to evaluate the effect of adding the enzyme phytase in the diet on the performance and eggs quality (experiment I) and the use of the feed ingredients (Experiment II) for laying Japanese quails. In the first experiment were used 320 quail females of Japanese sub- species, with 167 days old, initial weight of 182.3 + 3.8 g and rate of egg production of 89.0% and is divided into four and eight treatments repetitions of ten birds each. In experiment II were used 200 quail females of Japanese sub-species with 251 days old, average weight of 187.2 + 6.0 g and rate of egg production of 84.8%, distributed in four treatments and five repetitions of ten birds each. In both experiments using the completely randomized design. The treatments were: T1 - basal diet - RB - (given the nutritional requirements of quails and recommendations of the matrix of the enzyme phytase), T2 - RB + 200 U of phytase; T3 - RB + 400 U of phytase, T4 - RB + 600 U of phytase. The diets were formulated based on corn and soybean meal. The parameters of performance and eggs quality were evaluated in the experiment I: feed intake, egg production per bird day, eggs mass, efficient use of phosphorus for eggs mass, feed conversion per eggs mass and per eggs dozen, egg production per bird housed, viable eggs per bird day, feasibility studies, changes in body weight, lysine, methionine + cystine and threonine intake, egg weight, yolk weight, albumen weight, shell weight, percentage of yolk, albumen and shell, specific gravity and percentage of commercial eggs. Statistical analysis was made using the linear regression models, quadratic and Linear Response Plateau (LRP) as the best fit obtained for each variable. The best feed conversion occurred at levels of 437 (CAMO) and 400 (CADZ) U of phytase, however, considering the daily production of eggs per bird and production of viable eggs per bird day, the highest levels were 335 and 368 U of phytase, respectively. For MO the highest level of supplementation of phytase gave the best result. Meanwhile on the efficiency of the use of P, the level of 463 U of phytase was best for the composition of MO, while the other variables of performance and quality of eggs, filled with this level, in its ideal level of phytase. To determine the use of nutrients and energy in the diet (experiment II) was used the method of total collection of excreta. Were determined the values of apparent metabolizable energy and energy apparent metabolizable corrected by the retention of nitrogen, and metabolizability coefficient of apparent metabolizable energy and energy apparent metabolizable corrected by nitrogen balance. It was also calculated the amount of phosphorus, calcium and nitrogen detained by bird day. In general there was an improvement in the utilization of energy in the diet with phytase supplementation. Levels of 195 and 186 U of phytase are best designed to provide greater use of broiler apparent and apparent corrected by nitrogen balance. The level of 600 U of phytase the lowest nitrogen excretion, however, 368 U of phytase was enough for maximum retention of nitrogen by quails. The best level in the experiment I was 463 U of phytase and the experiment II was of 368 U of phytase. / Foram realizados dois experimentos para avaliar o efeito da adição da enzima Fitase na ração, sobre o desempenho produtivo e a qualidade dos ovos (experimento I) e o aproveitamento dos ingredientes da ração (experimento II) para codornas japonesas em postura. No experimento I foram utilizadas 320 codornas fêmeas da sub-espécie japonesa, com 167 dias de idade, peso inicial médio de 182,3 + 3,8g e taxa de produção de ovos de 89,0%, sendo distribuídas em quatro tratamentos e oito repetições de dez aves por unidade experimental. No experimento II foram utilizadas 200 codornas fêmeas da sub-espécie japonesa com 251 dias de idade, peso médio de 187,2 + 6,0g e taxa de produção de ovos de 84,8%, distribuídas em quatro tratamentos e cinco repetições de dez aves por unidade experimental. Em ambos os experimentos utilizou-se o delineamento inteiramente casualizado. Os tratamentos foram: T1 Ração basal RB - (atendendo às exigências nutricionais das codornas e as recomendações da matriz da enzima fitase); T2 - RB + 200 U de fitase; T3 - RB + 400 U de fitase; T4 - RB + 600 U de fitase. As rações foram formuladas à base de milho e farelo de soja. Os parâmetros de desempenho e de qualidade dos ovos avaliados no experimento I foram: consumo de ração, produção de ovos por ave dia, massa de ovos, eficiência de utilização de fósforo para massa de ovos, conversão alimentar por massa de ovos e por dúzia de ovos, produção de ovos por ave alojada, ovos viáveis por ave dia, viabilidade, variação de peso corporal, consumo de lisina, metionina + cistina e treonina, peso dos ovos, peso de gema, peso de albúmem, peso de casca, porcentagens de gema, albúmem e casca, gravidade específica e percentual de ovos comercializáveis. As análises estatísticas foram feitas utilizando-se os modelos de regressão linear, quadrática e Linear Response Plateau (LRP), conforme o melhor ajustamento obtido para cada variável. A melhor conversão alimentar ocorreu nos níveis de 437 (CAMO) e de 400 (CADZ) U de fitase, entretanto, considerando a produção diária de ovos por ave e a produção de ovos viáveis por ave dia, os melhores níveis foram 335 e 368 U de fitase, respectivamente. Para MO o maior nível de suplementação de fitase proporcionou o melhor resultado. Entretanto em relação à eficiência do uso do P, o nível de 463 U de fitase foi o melhor para composição da MO, sendo as demais variáveis de desempenho produtivo e qualidade dos ovos, supridas com este nível, em seus níveis ideais de fitase. Para determinação do aproveitamento dos nutrientes e energia das rações (experimento II) foi utilizado o método de coleta total de excretas. Foram determinados os valores de energia metabolizável aparente e de energia metabolizável aparente corrigida pela retenção de nitrogênio, e os coeficientes de metabolizabilidade da energia metabolizável aparente e da energia metabolizável aparente corrigida pelo balanço de nitrogênio. Foi calculada também a quantidade de fósforo, cálcio e nitrogênio retido por ave dia. De maneira geral houve uma melhora no aproveitamento da energia das rações com a suplementação de fitase. Os níveis de 195 e 186 U de fitase são os mais indicados para proporcionar maior aproveitamento da energia metabolizável aparente e aparente corrigida pelo balanço de nitrogênio. O nível de 600 U de fitase proporcionou menor excreção de nitrogênio, entretanto, 368 U de fitase foi suficiente para máxima retenção de nitrogênio pelas codornas. O melhor nível no experimento I foi de 463 U de fitase e no experimento II foi de 368 U de fitase.

Made available in DSpace on 2015-03-26T13:54:45Z (GMT). No. of bitstreams: 1 texto completo.pdf: 183039 bytes, checksum: b094ae15fafe623b510bd03b4d73b265 (MD5) Previous issue date: 2008-03-07 / Two experiments were driven in the Section of Aviculture of the Department of Zootecnia of the Universidade Federal de Viçosa - UFV, with the objective of determining the best method of forced seedling for Japanese and rising quail to determine the best fast period and his/her reflex about the parameters of productive acting and egg quality. In the experiment I 315 Japanese quails were used with 60 weeks of age. The phase changes forced it consisted of the supply of differentiated diets (treatments) during a period of 10 days and phase powderseedling consisted of 10 periods of 7 days each. The treatments were: T1 - ration of comfortable posture (it controls), T2 - ration fast for 2 days and 8 days of ration of it recreates, T3 - 5 days of posture ration with excess of Zn (10.000ppm) and 5 days with ration of it recreates, T4 - posture ration with deficiency in Na and T5 - supply during 5 days of corn maize flour and 5 days of ration of it recreates. Fast hídrico was not used. Delineamento was used casualizado entirely with 5 treatments, 7 repetitions and 9 birds for experimental unit. In the experiment II 168 Japanese quails were used with 62 weeks of age. The phase changes forced it consisted of the supply of differentiated diets (treatments) during a period of 10 days and phase powder- seedling consisted of 12 periods of 7 days each. The treatments were: T1 - posture ration the will (it controls), T2 - ration fast for 2 days and 8 days of ration of it recreates, T3 - ration fast for 3 days and 7 days of ration of it recreates. Fast hídrico was not used. Delineamento was used casualizado entirely with 3 treatments, 7 repetitions and 8 birds for experimental unit. The parameters analyzed for the two experiments were consumption of ration bird day (CRAD), production of eggs (POAD), marketable eggs (OC), weight of eggs (PO), egg mass (MO), alimentary conversion for egg mass (CAMO), alimentary conversion for dozen of egg (CADZO), gravity specifies (GE), viability (VIAB) and I weigh corporal (PI, PF, GP and PP). For the experiment I there was not significant difference (p>0,05) among the analyzed parameters CRAD, PO and GE. For POAD there was difference (P <0,05), and the birds of T2 obtained better acting, however the same treatment resulted in high mortality. For CADZO and CAMO there was significant difference (P <0,05), and the best values went to the treatment to control (T1) and the treatment with 2 days of fast and 8 days of ration of it recreates (T2). This way the forced seedling for quail doesn't result in improvement in the analyzed parameters. For the experiment II there was not significant effect (p>0,05) of the treatments for none of the appraised parameters. However, it was observed that in absolute values, POAD of the treatment controls (T1) it was superior to 10,45% in relation to the treatment fast of 2 days (T2) and superior to 4,44% to the treatment fast of 3 days (T3). Para VIAB the treatment controls (T1) it was inferior to 4,76% in relation to the treatment fast of 2 days (T2) and inferior to 1,86% to the treatment fast of 3 days (T3). this way it is not viable the practice of the alimentary fast for 2 or 3 days as technique of forced seedling for Japanese quail. / Foram conduzidos dois experimentos no Setor de Avicultura do Departamento de Zootecnia da Universidade Federal de Viçosa UFV, com o objetivando-se avaliar diferentes métodos de muda forçada para codorna japonesa sobre os parâmetros de desempenho produtivo e qualidade de ovo. No experimento I foram utilizadas 315 codornas japonesas com 60 semanas de idade. A fase muda forçada consistiu no fornecimento de dietas diferenciadas (tratamentos) durante um período de 10 dias e fase pós-muda consistiu em 10 períodos de 7 dias cada. Os tratamentos foram: T1 ração de postura à vontade (controle), T2 - jejum de ração por 2 dias seguidos de 8 dias de ração de recria à vontade, T3 - 5 dias de ração de postura à vontade com excesso de Zn (10.000ppm) seguidos de 5 dias com ração de recria à vontade, T4 - ração de postura à vontade com deficiência em Na e T5 - 5 dias de milho moído seguidos de 5 dias de ração de recria à vontade. Não foi utilizado jejum hídrico. Utilizou-se delineamento inteiramente casualizado com 5 tratamentos, 7 repetições e 9 aves por unidade experimental. No experimento II foram utilizadas 168 codornas japonesas com 62 semanas de idade. A fase de muda forçada consistiu no fornecimento de dietas diferenciadas (tratamentos) durante um período de 10 dias e fase pós-muda consistiu em 12 períodos de 7 dias cada. Os tratamentos foram: T1 ração de postura à vontade (controle), T2 - jejum de ração por 2 dias seguidos de 8 dias de ração de recria à vontade, T3 - jejum de ração por 3 dias seguidos de 7 dias de ração de recria à vontade. Não foi utilizado jejum hídrico. Utilizou-se delineamento inteiramente casualizado com 3 tratamentos, 7 repetições e 8 aves por unidade experimental. Os parâmetros analisados para os dois experimentos foram consumo de ração ave dia (CR), produção de ovos (POAD), ovos comercializáveis (OC), peso de ovos (PO), massa de ovo (MO), conversão alimentar por massa de ovo (CAMO), conversão alimentar por dúzia de ovo (CADZO), gravidade especifica (GE), viabilidade (VIAB) e peso corporal (PI, PF, GP e PP). Para o experimento I não houve diferença significativa (p>0,05) para os parâmetros analisados (CRAD, PO e GE). Para POAD houve diferença (P<0,05), sendo que as aves do tratamento com 2 dias de jejum e 8 dias de ração de recria (T2) obtiveram melhor desempenho, no entanto o mesmo tratamento resultou em elevada mortalidade. Para CADZO e CAMO houve diferença significativa (P<0,05), sendo que os melhores valores foram para o tratamento controle (T1) e o tratamento com 2 dias de jejum e 8 dias de ração de recria (T2). O método de jejum alimentar por 2 dias, seguidos de 8 dias de ração de recria à vontade, é o melhor para induzir muda forçada em codorna japonesa, porém, a muda forçada realizada por meio das técnicas testadas não foi capaz de promover melhora da produtividade das codornas japonesas no período pós muda. Para o experimento II não houve efeito significativo (p>0,05) dos tratamentos para nenhum dos parâmetros avaliados. No entanto, observouse que em valores absolutos, a POAD do tratamento controle (T1) foi superior a 10,45% em relação ao tratamento jejum de 2 dias (T2) e superior a 4,44% ao tratamento jejum de 3 dias (T3). Para VIAB o tratamento controle (T1) foi inferior a 4,76% em relação ao tratamento jejum de 2 dias (T2) e inferior a 1,86% ao tratamento jejum de 3 dias (T3). O método de jejum alimentar por 3 dias, seguidos de 7 dias de ração de recria à vontade, é o melhor para induzir muda forçada em codorna japonesa, porém, a muda forçada realizada por meio das técnicas testadas não foi capaz de promover melhora da produtividade das codornas japonesas no período pós muda.