A significant proportion of potential lambs are lost (commonly 15-20%) between ovulation and day 30 of gestation. Moreover, little is known about factors associated with multiple birth capacity of the uterus which would be necessary to convert gains in ovulation rate to the birth of live lambs. This project has investigated the relationship between maternal uterine and hormonal environment as well as the heritability of embryonic survival (ES) in prolific ewes. Litter size (LS) from known ovulation rate (OR) records (n=6393) collected over 16 years were analysed for heritability. ASReml analysis reported ES to be a trait of low repeatability (r� = 0.103) and heritability (h� = 0.04) which is consistent with earlier studies of this trait. However, pedigrees of outlier animals indicated a segregation pattern consistent with a single autosomal gene with a major affect on enhanced ES. From this flock, closely related high ovulation rate ewes with significantly different litter sizes (High ES; OR2.6/LS2.4 versus Low ES; OR2.9/LS1.6) were selected for further study. The anatomy and gene expression of the uterus collected at day 14 of the oestrous cycle (n=5 High and n=5 Low ES ewes) and day 16 of gestation (n=14 high and n=10 Low ES ewes) as well as systemic concentrations of hormones indicative of uterine (activin-A, follistatin) and ovarian (inhibin-α, progesterone) function during the oestrous cycle and early gestation were compared. Progesterone concentrations were found to rise earlier in high ES ewes with a difference in number of ewes with detectable levels of progesterone apparent by day 4 of gestation. The peak concentration and slope of progesterone increase as well as plasma profiles of oestradiol and inhibin-α were not different between groups. A number of pathways worthy of closer investigation were implicated by microarray analysis with Ingenuity Pathway Analysis, Pubmatrix, and candidate gene approaches. In particular, the altered expression of many immune cell factors suggests that high ES ewes have maternal gene expression of the inflammatory pathways favourable to embryo implantation. The plasma concentration of activin, but not follistatin, was found to be significantly higher in low ES ewes, a difference that remained apparent when the concentration of follistatin was corrected for individual samples. Furthermore, the concentration of activin, but not follistatin, was significantly elevated on day 16 of gestation in the uterine fluid of low ES ewes. Further investigation of the pattern of gene expression during the oestrous cycle and early gestation (day10-16 oestrus and days10-20 gestation) revealed that a significant increase in follistatin mRNA in the luminal epithelia and interacting trophoblast cells of the embryo occurs on day 18 and 20 of gestation. It is likely the appropriate balance between activin and follistatin during the time of implantation enhances embryonic survival in this line of ewes. This may be secondary to or concomitant with the observed earlier rise in progesterone concentration. The implication that embryo survival may be positively influenced by a single autosomal gene has important implications for New Zealand's agricultural industry.

A significant proportion of potential lambs are lost (commonly 15-20%) between ovulation and day 30 of gestation. Moreover, little is known about factors associated with multiple birth capacity of the uterus which would be necessary to convert gains in ovulation rate to the birth of live lambs. This project has investigated the relationship between maternal uterine and hormonal environment as well as the heritability of embryonic survival (ES) in prolific ewes. Litter size (LS) from known ovulation rate (OR) records (n=6393) collected over 16 years were analysed for heritability. ASReml analysis reported ES to be a trait of low repeatability (r� = 0.103) and heritability (h� = 0.04) which is consistent with earlier studies of this trait. However, pedigrees of outlier animals indicated a segregation pattern consistent with a single autosomal gene with a major affect on enhanced ES. From this flock, closely related high ovulation rate ewes with significantly different litter sizes (High ES; OR2.6/LS2.4 versus Low ES; OR2.9/LS1.6) were selected for further study. The anatomy and gene expression of the uterus collected at day 14 of the oestrous cycle (n=5 High and n=5 Low ES ewes) and day 16 of gestation (n=14 high and n=10 Low ES ewes) as well as systemic concentrations of hormones indicative of uterine (activin-A, follistatin) and ovarian (inhibin-α, progesterone) function during the oestrous cycle and early gestation were compared. Progesterone concentrations were found to rise earlier in high ES ewes with a difference in number of ewes with detectable levels of progesterone apparent by day 4 of gestation. The peak concentration and slope of progesterone increase as well as plasma profiles of oestradiol and inhibin-α were not different between groups. A number of pathways worthy of closer investigation were implicated by microarray analysis with Ingenuity Pathway Analysis, Pubmatrix, and candidate gene approaches. In particular, the altered expression of many immune cell factors suggests that high ES ewes have maternal gene expression of the inflammatory pathways favourable to embryo implantation. The plasma concentration of activin, but not follistatin, was found to be significantly higher in low ES ewes, a difference that remained apparent when the concentration of follistatin was corrected for individual samples. Furthermore, the concentration of activin, but not follistatin, was significantly elevated on day 16 of gestation in the uterine fluid of low ES ewes. Further investigation of the pattern of gene expression during the oestrous cycle and early gestation (day10-16 oestrus and days10-20 gestation) revealed that a significant increase in follistatin mRNA in the luminal epithelia and interacting trophoblast cells of the embryo occurs on day 18 and 20 of gestation. It is likely the appropriate balance between activin and follistatin during the time of implantation enhances embryonic survival in this line of ewes. This may be secondary to or concomitant with the observed earlier rise in progesterone concentration. The implication that embryo survival may be positively influenced by a single autosomal gene has important implications for New Zealand's agricultural industry.

Thesis (Ph. D.)--University of Adelaide, 1985. / Includes bibliographical references (leaves 182-210).

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2003. / Härtill 4 uppsatser.

Thesis (M.S.)--West Virginia University, 2000. / Title from document title page. Document formatted into pages; contains viii, 46 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 33-38).

Orientador: Américo Garcia da Silva Sobrinho / Banca: Sarita Bonagurio Gallo / Banca: Cledson Augusto Garcia / Banca: Otávio Rodrigues Machado Neto / Banca: Carla Joice Härter / Resumo: Foram utilizadas cinquenta ovelhas Ile de France submetidas à programação fetal, que consistiu no fornecimento de dietas com dois níveis de energia, uma dieta controle para atender as exigências nutricionais do terço final de gestação (D0), e outra acrescida em 20% das exigências de energia para a categoria (D20). Avaliou-se a influência nutricional no escore de condição corporal, peso corporal, espessura de gordura e perfil metabólico das ovelhas, no momento do parto e aos 15, 30, 45 e 60 dias de lactação, assim como a repercussão nos cordeiros, tais como desempenho, características quantitativas da carcaça e de seus não-componentes, qualitativas da carne e na morfometria dos componentes gastrintestinais. O delineamento experimental utilizado foi o inteiramente casualizado, com dois tratamentos e 20 repetições (experimento com as ovelhas) e dois tratamentos e 10 repetições (experimento com os cordeiros), nível de significância de 5% e auxiliado pelo programa do SAS (versão 9.2). Nas comparações entre dietas e as variáveis respostas das ovelhas utilizou-se contrastes ortogonais polinomiais (1º, 2º, 3º e 4º grau). As médias das características corporais das ovelhas foram semelhantes (P>0,05), com decréscimo gradual ao longo dos 60 dias de lactação, para peso corporal, escore condição corporal e espessura de gordura. Observou-se efeito quadrático (P<0,05) nos valores médios de glicose, triglicerídeos e betahidroxibutirato, no decorrer dos 30 dias após o parto. O acréscimo em 20... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Fifty Ile de France ewes were subjected to fetal programming, which consisted of feeding them diets with two levels of energy: one control diet formulated to meet the nutritional requirements of the last third of gestation (D0) and another with an additional 20% of the energy requirements of the category (D20). We evaluated the nutritional influence on the body condition score, body weight, fat thickness, and metabolic profile of ewes at calving and at 15, 30, 45, and 60 days in milk, as well as the impacts on their lambs; e.g., performance, quantitative traits of carcass and of noncarcass components, qualitative traits of their meat, and morphometry of their gastrointestinal components. A completely randomized design with two treatments and 20 replicates (experiment with the ewes) and two treatments and 10 replicates (experiment with the lambs) was adopted at a significance level of 5%, with analyses run in SAS software (version 9.2). Orthogonal polynomial contrasts (1st-, 2nd-, 3rd-, and 4th-degree) were used in the comparison between diets and the response variables of the ewes. Mean values for the body traits of the ewes were similar (P>0.05), decreasing gradually along the 60 days in milk for body weight, body condition score, and fat thickness. A quadratic effect was observed (P<0.05) for mean glucose, triglycerides, and beta-hydroxybutyrate values over the 30 days after calving. The additional 20% of the energy required for the last third of gestation in the ewe diets ... (Complete abstract click electronic access below) / Doutor

Made available in DSpace on 2014-06-11T19:26:01Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-06-06Bitstream added on 2014-06-13T19:33:12Z : No. of bitstreams: 1 oliveira_aa_me_botfmvz.pdf: 347105 bytes, checksum: 1ec55233b36898aa75caa16e2d19d24d (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Universidade Estadual Paulista (UNESP) / Pelo presente estudo avaliou-se a inclusão de óleo de linhaça sobre a produção, constituintes do leite, dinâmica do peso corporal das ovelhas e desempenho dos cordeiros de ovelhas da raça Bergamácia. Quarenta e oito ovelhas foram distribuídas em dois grupos: Controle (C): suplementadas com concentrado sem óleo de linhaça (0,800 kg/ovelha/dia) e Linhaça (L): suplementadas com concentrado acrescido de óleo de linhaça (0,700 kg/ovelha/dia). As ovelhas permaneceram com seus cordeiros até 30 dias de idade, quando foram desmamados. Durante o dia as ovelhas ficaram na pastagem de Panicum maximum cv. Tanzânia e durante o período noturno elas eram recolhidas a um galpão e recebiam silagem de sorgo. Foram ordenhadas duas vezes ao dia e tiveram suas produções controladas. As amostras de leite para análise da composição centesimal foram colhidas a cada 14 dias a partir do primeiro dia de ordenha. Para avaliação da dinâmica do peso corporal os animais eram pesados a cada 14 dias, juntamente com a determinação do escore de condição corporal. Os cordeiros foram pesados a cada 7 dias, até desmama. Não foram encontradas diferenças entre os tratamentos (P>0,05) para pesos ao parto, à desmama, e final, e ganho de peso das ovelhas. Os tratamentos também não influenciaram o peso ao nascer, à desmama e o ganho de peso dos cordeiros. A inclusão de óleo de linhaça não alterou a produção de leite e seus constituintes: gordura, proteína, lactose, sólidos totais, extrato seco desengordurado e contagem de células somáticas / For this study, the inclusion of linseed oil on milk production, its components, dynamics of body weight and on the performance of lambs of Bergamasca ewes was evaluated. Forty-eight ewes were distributed in two groups: Control (C): supplemented with concentrate without linseed oil (0.800 kg/ewe/day) and Linseed (L): supplemented with concentrate of linseed oil (0.700 kg/ewe/day). The ewes stayed with their lambs until they were 30 days old - when they were weaned. During the day the ewes remained in Panicum maximum cv. Tanzania pasture and at night they were gathered in a pen and received sorghum silage. They were milked twice a day and had their productions controlled. The milk samples for the proximate composition analysis were taken every 14 days from the first milking day. Every 14 days, for the evaluation of body weight dynamics, the animals were weighed and their body condition score was determined. The lambs were weighed every 7 days until weaning. No differences were found between treatments (P> 0.05) for birthweight, weaning and final weight gain of the ewes. The treatments did not affect birthweight, weaning weight and weight gain of the lambs. The inclusion of linseed oil did not affect milk production or its components - fat, protein, lactose, total solids, nonfat dry extract, and somatic cell count

Made available in DSpace on 2014-11-10T11:09:54Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-02-19Bitstream added on 2014-11-10T11:57:45Z : No. of bitstreams: 1 000790984.pdf: 975793 bytes, checksum: 351b59187c3c1fb155f92b0d93b504b9 (MD5) / Este estudo teve como objetivos: investigar os micro-organismos causais da mastite subclínica em ovelhas de aptidão para produção de carne, definir pontos de corte de dois métodos de diagnóstico indiretos, comparar as taxas de cura do tratamento da mastite subclínica após infusão intramamária de princípio ativo antimicrobiano no momento da secagem em duas diferentes formulações, convencional e nanoparticulada, verificar as taxas de cura espontânea, avaliar a capacidade de prevenção da ocorrência de novas infecções mamárias e verificar a presença de resíduos antimicrobianos no leite de ovelhas submetidas ao tratamento à secagem, na lactação consecutiva. O estudo foi realizado em um rebanho localizado em uma propriedade no município de São Carlos, São Paulo. Analisou-se um total de 393 mamas de ovelhas de aptidão para produção de carne, 250 das quais pertencentes a 130 ovelhas da raça Santa Inês e outras 143 mamas de 77 ovelhas da raça Morada Nova. Amostras de leite foram coletadas e submetidas ao exame de California Mastitis Test (CMT), à contagem de células somáticas (CCS) e ao exame microbiológico antes da secagem e após o parto subsequente. As glândulas mamárias com mastite subclínica foram distribuídas nos seguintes grupos: G1 (Controle; glândulas mamárias que não receberam tratamento antimicrobiano); G2 (glândulas mamárias em que foi administrado 100 mg de cloxacilina benzatina/ 10 mL em estrutura convencional) e G3 (glândulas mamárias em que foi administrado 50 mg de cloxacilina benzatina/ 86 mL em estrutura nanoencapsulada). Para avaliação dos tratamentos quanto à capacidade de prevenir novas infecções, foram utilizadas as mamas saudáveis dos animais dos grupos experimentais G1, G2 e G3, e foi acrescido o grupo G4 (glândulas mamárias saudáveis em que foi administrado 100 mg de cloxacilina benzatina/ 172 mL em estrutura nanoencapsulada) ... / This study had as objectives: investigate the microorganisms that cause subclinical mastitis in meat producing sheep, define cut-off values of two methods of indirect diagnosis, compare cure rates of treatment of subclinical mastitis after intramammary infusion of antimicrobial active principle at the time of drying off in two different formulations, conventional and nanoparticle, check the rates of spontaneous cure, evaluate the capability of prevention of new infections and check the presence of antimicrobial residues in milk of sheep subjected to treatment during drying off, on consecutive lactation. The study was done in a flock located on a property in São Carlos city, São Paulo. We analyzed a total of 393 mammary glands of meat producing sheep, 250 of which belong to 130 Santa Inês breed sheep and other 143 mammary glands of 77 Morada Nova breed sheep. Milk samples were collected and submitted to California Mastitis Test (CMT), the somatic cell count (SCC) and microbiological exam before drying off and after subsequent parturition. The mammary glands with subclinical mastitis were as follows: G1 (Control, mammary glands that not received antibiotic treatment), G2 (mammary glands which was administered 100 mg of benzathine cloxacillin/ 10 mL in conventional structure) and G3 (mammary glands which was administered 50 mg benzathine cloxacillin/ 86 mL in nanocoated structure). For evaluation of treatments about their capability to prevent new infections, we used the mammary glands of healthy animals of experimentals groups groups G1, G2 and G3, and G4 was added group (healthy mammary glands, which was administered 100 mg of benzathine cloxacillin/ 172 mL in nanocoated structure). The occurrences of animals positive for infectious mastitis in Santa Ines breed sheep was 33.1% and 35.6% in Morada Nova breed sheep. Coagulase-negative Staphylococci were the predominant etiologic agents ...

Made available in DSpace on 2014-06-11T19:27:43Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-02-16Bitstream added on 2014-06-13T19:06:51Z : No. of bitstreams: 1 emediato_rms_me_botfmvz.pdf: 408774 bytes, checksum: 490883dafcb0a7067abad1d4a6c0f2b5 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / Delineou-se o presente trabalho com o objetivo de avaliar o efeito do uso de gordura protegida na dieta d ovelhas da raça Bergamácia sobre o desempenho produtivo, dinâmica de peso e nas medidas do úbere. Utilizou-se 77 ovelhas distribuídas em 2 grupos de forma homogênea por ordem de parição idade. Para os dois tratamentos propostos, utilizou-se: dieta Controle (C): silagem de milho e concentrado; e dieta Gordura Protegida (GP): a mesma de C e adição de gordura ruminalmente protegida (35 g/ovelha/dia) ao concentrado. As dietas foram isoenergéticas e isoprotéicas, contendo 16% PB e 70% NDT com base na matéria seca. Os cordeiros permaneceram com suas mães em pasto durante o dia e separados à noite. Eles retornavam à suas mães após a ordenha matinal e foram desmamados aos 45 dias de idade. As ovelhas, após 48 horas do parto, foram ordenhadas mecanicamente uma vez ao dia, às 7h 00, com produção de leite mensurada diariamente pelo período de 60 dias. Amsotras de leite foram coletadas semanalmente para determinação de proteína e gordura. Foram medidas a circunferência, profundidade e largura do úbere e largura e comprimento das tetas, aos 30 e 60 dias. O tratmaneto GP apresentou maior produção de leite média diária após a desmama dos cordeiros (0,531 vs 0,489 kg/cab/dia), entretanto, a produção de todo o período não foi diferente entre os tratamentos (0,468 vs 0,453 kg/cab/dia, para GP e C, respectivamente). As produções de leite ajustadas para 6,5% de gordura e 6,5% de gordura e 5,8% de proteína forma semelhantes entre os tratamentos. A utilização de 3,5% de gordura protegida no concentrado de ovelhas leiteiras foi economicamente viável, proporcionando produção de leite 12,7% maior após a 7ª semana de lactação. / This work aimed to evaluate the effect of use of protected fat in the diet of Bergamasca ewes on its performance and weight ranging. It was used 77 ewes allocated in 2 homogeneous groups by partutition and age. Following diets were used: control diet (C): corn silage and concentrate; and protected fat diet (GP): same of C and ruminally protected fat (35 g/ewe/d) added to concentrate. Diets were isoenergetic and isonitrogenous, containing 16% CP and 70% TDN on a dry-matter basis. lambs were kept with their mothers in pasture during daytime and were separated at night. They were returned to their mothers after the morning and were weaned at 45 days of age. After 48 hs postpartum, ewea were machine milked once a day at 7h 00, and milk production was daily measured for a period of 60 days. Milk samples were collected for protein and fat determination. Treatment GP presented higher daily average milk production after lambs weaning (0.531 vs 0.489 kg/head/d), however, average milk production of the whole period was not different (0.468 vs 0.453 kg/head/d for GP and C, respectively). Adjusted milk production for 6.5% fat and 6.5% fat and 5.8% protein were similar between treatments. After weaning, treatment C presented higher milk fat content. The use of 3.5% of protected fat on ewes concentrate was economically viable and milk production increases 12.7% after seventh lactation week.

Orientador: Luiz Francisco Zafalon / Banca: Estevam Guilherme Lux Hoppe / Banca: Raimundo Nonato Rabelo / Resumo: Objetivou-se estabelecer a etiologia infecciosa da mastite subclínica ovina em duas diferentes fases de lactação e a frequência desta enfermidade nas diferentes raças. Além disso, buscou-se definir as características diagnósticas da contagem de células somáticas (CCS) para o diagnóstico da mastite subclínica ovina, adotando diferentes classes de contagens de CCS, assim como estabelecer um valor de triagem para a CCS como método diagnóstico. O trabalho experimental foi realizado em um rebanho formado por 407 ovelhas das raças Santa Inês, Texel, Ile de France e Dorper, localizado na Embrapa Pecuária Sudeste em São Carlos, São Paulo. O California Mastitis Testis (CMT) foi realizado para o diagnóstico preliminar da mastite. Após a antissepsia dos tetos, amostras de leite foram colhidas no início de lactação e ao desmame, em duas parições consecutivas para confirmação da etiologia infecciosa da doença por meio de análises microbiológicas e para a determinação da CCS. Para cada uma das raças os valores de CCS foram divididos em quatro classes. O total de 1457 metades mamárias foi investigado, das quais 203 (13,9%) apresentaram mastite subclínica. Estafilococos coagulase-negativos (ECN) foram os agentes etiológicos com maior ocorrência isoladamente e em associação, 58,1% e 60,6%, respectivamente, seguidos por Streptococcus spp. (19,7%). Dentre os ECN, a espécie encontrada com maior frequência foi Staphylococcus xylosus (87,7%). A raça Santa Inês apresentou significativamente maior n... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This study aimed to establish the infectious etiology of subclinical mastitis in two different stages of lactation and the frequency of this disease in different breeds sheep. Furthermore, we sought to define the diagnostic characteristics of somatic cell count (SCC) for the diagnosis of subclinical mastitis in these sheep breeds, adopting different classes of SCC, and establish a screening value for SCC as diagnostic method. The experimental work was carried out in a herd composed of 407 sheep of Santa Inês, Texel, Ile de France and Dorper breeds, located in the Embrapa Southeast Livestock, São Carlos, São Paulo. The California Mastitis Test (CMT) was performed for a preliminary diagnosis of mastitis. After antisepsis of the teats, milk samples were collected in early lactation and weaning in two consecutive calvings for confirmation of infectious etiology of the disease by microbiological analysis and the determination of SCC. For each breed, CCS values were divided into four classes. We investigated 1,457 mammary glands, from which 203 (13.9%) had subclinical mastitis. Coagulase-negative staphylococci (CNS) were the etiological agents with higher occurrence isolated or in an association, 58.1% and 60.6%, respectively, followed by Streptococcus spp. (19.7%). Among the CNS, the most frequent species was Staphylococcus xylosus (87.7%).The Santa Inês breed had a significantly higher number of cases of subclinical mastitis (p < 0.05). Good and excellent concordances to the asso... (Complete abstract click electronic access below) / Mestre