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Eficiência produtiva e reprodutiva em vacas leiteiras  [cached]
Leite Tisa Echevarria,Moraes José Carlos Ferrugem,Pimentel Cláudio Alves
Ciência Rural , 2001,
Abstract: O presente trabalho teve por objetivo avaliar efeitos de transtornos puerperais sobre a eficiência reprodutiva e produtiva de vacas da ra a Holandês de uma esta o experimental, durante 24 anos. Foram coletados dados produtivos e reprodutivos de 350 vacas. Todos os dados foram submetidos à análise descritiva. As variáveis dependentes: intervalo entre partos (IEP), intervalo parto concep o (IPC), intervalo parto primeiro cio (IPPC), número de crias (NC) e produ o de leite (PL) foram submetidas a análise de variancia para determina o dos efeitos da ocorrência de transtornos puerperais (aborto, natimorto, distocia e reten o de placenta) e de mastite. A idade ao primeiro cio (IdPC) foi de 29,4 meses, a idade ao primeiro parto (IdPP) de 37,1 meses e a longevidade (L) de 69,7 meses. O IEP apresentou média de 14,6 meses, o IPPC de 97,0 dias e o IPC de 150,7 dias. O intervalo entre cios (IEC) apresentou média de 48,2 dias, sugerindo falhas na detec o de cios. Foi observado efeito significativo (P<0,05) da ocorrência de aborto sobre o IEP, com esse intervalo sendo 258 dias maior em vacas que apresentaram esse transtorno. A ocorrência de distocia (P<0,05) e natimorto (P<0,01) afetou significativamente o IPC, representando aumentos desse intervalo em 82,4 e 136,1 dias, respectivamente. O IPCC foi o índice menos sensível aos efeitos das desordens reprodutivas, n o tendo sofrido efeito de nenhum dos transtornos. A PL foi associada à distocia (P<0,05). Os animais que apresentaram distocia produziram 380,5kg de leite a menos do que vacas que n o a apresentaram. A partir da análise dos resultados, concluiu-se que procedimentos preventivos para controlar a saúde do rebanho, exames clínicos criteriosos de problemas pós-parto e o monitoramento de dados com informa es precisas para a análise periódica dos índices produtivos e reprodutivos podem contribuir para uma produ o leiteira mais racional e econ mica.
Eficiência Reprodutiva e Produtiva em Rebanhos Leiteiros Comerciais Monitorados por Sistema Informatizado  [cached]
Grossi Selma de Fátima,Freitas Maria Armênia Ramalho de
Revista Brasileira de Zootecnia , 2002,
Abstract: O estudo foi conduzido com os objetivos de analisar o desempenho produtivo e algumas medidas de eficiência reprodutiva de 1877 vacas provenientes de quatro grupos genéticos Holandês fraction three-quarters Zebu e estimar os parametros genéticos pertinentes. Os animais pertenciam a três rebanhos comerciais que foram monitorados pelo Sistema Computacional de Informa o DAISY (The Dairy Information System), durante período de 1989 a 1998. Para consistência dos dados, forma o dos arquivos e análises preliminares foram usados os procedimentos disponíveis no SAS (Statistical Analysis System), enquanto os componentes de (co)variancia foram estimados pelo método de máxima verossimilhan a restrita livre de derivada (MTDFREML), sob um modelo animal. Os efeitos de grupo genético e ano do parto foram significativos sobre a idade da vaca ao primeiro parto (IPC), intervalo parto - primeiro servi o (PP1S), dura o da lacta o(DL), produ o total de leite (PT) e produ o de leite por dia de intervalo de parto (PLIEP). As estimativas de herdabilidade (h2) para as características reprodutivas ficaram próximas de zero, evidenciando grande dependência do manejo oferecido aos rebanhos, enquanto o valor de 0,28 para a h2 da PT mostrou variancia genética aditiva média. A correla o genética entre PT e DL de 0,81 pode ser considerada de alta magnitude.
Eficiência Reprodutiva e Produtiva em Rebanhos Leiteiros Comerciais Monitorados por Sistema Informatizado
Grossi, Selma de Fátima;Freitas, Maria Armênia Ramalho de;
Revista Brasileira de Zootecnia , 2002, DOI: 10.1590/S1516-35982002000600006
Abstract: the objectives of this work were to evaluate the productive and reproductive efficiencies and also the genetics parameters for traits considered, using data from 1877 crossbreed cows (holstein x zebu) from four genetics groups. the cows belonged to three commercial dairy herds monitored from 1989 to 1998 by the dairy information system (daisy). the data were processed using the procedure available in sas (statistical analysis system), while genetic parameters on productive and reproductive traits were estimated by the multiple trait derivative-free restricted maximum likelihood method (mtdfreml). effects of genetic group and calving year were significant for age at first calving (afc), interval from calving to first service (icfs), lactation length (ll), milk production (my) and milk production per day of calving interval (myci). the estimates of heritability (h2) for all reproductive traits were near zero in agreement with others studies indicating that these traits are mostly determined by management practices. the h2 estimates for milk yield (my) were 0.28, this means that the additive genetic variance is middle. the genetic correlations (rg) between my and ll of 0.81 could be considered high.
Influência da freqüência de ordenhas diárias sobre a eficiência produtiva de vacas mesti?as Holandês-Zebu e o desempenho dos seus bezerros
Ruas, José Reinaldo Mendes;Brand?o, Felipe Zandonadi;Silva Filho, José Monteiro da;Borges, álan Maia;Carvalho, Bruno Campos de;Menezes, Arismar de Castro;Amaral, Reginaldo;Marcatti Neto, Alberto;
Revista Brasileira de Zootecnia , 2006, DOI: 10.1590/S1516-35982006000200013
Abstract: this trial was conducted to study the effects of daily milking frequency on milk yield, duration of lactation, incidence of mastitis, and calves body weight gain. sixty-three crossbred holstein-zebu cows were equally and randomly assigned to three experimental groups according to the frequency of daily milkings as follows: once a day milking, twice a day milking, or alternating once or twice a day milking every 14 days. the duration of lactation, mammary gland health, and calf production did not differ among treatments in this study. however, cows milked twice a day yielded 24.54% more milk per lactation (699.9 kg) compared to the other milking regimes.
Crecimiento de hembras cruzadas en el trópico colombiano Crescimento de fêmeas cruzadas no tropico colombiano Growth of crossbred females in the Colombian tropic
Edison J Ramírez,Mario F Cerón Mu?oz,Ana C Herrera,Oscar D Vergara
Revista Colombiana de Ciencias Pecuarias , 2009,
Abstract: El presente trabajo tuvo como objetivo describir el crecimiento de hembras cruzadas de seis grupos genéticos por medio del modelo de Brody. Los grupos genéticos evaluados fueron 50% Angus 50% Cebú (AC), 50% BON 50% Cebú (BC), 100% Cebú (C), 50% Romosinuano 50% Cebú (RC), 50% Senepol 25% Angus 25% Cebú (SAC), 50% Senepol 50%Cebú (SC). Se estimó el Porcentaje de madurez a los 12, 18 y 24 meses y las edades al 75% y al 95% de madurez. La madurez a los 12 meses varió entre 42% y 48.5%, a los 18 entre 53% y 60% y a los 24 meses entre 61% y 69%; el grupo genético más precoz fue AC y el menos precoz BC. La edad al 75% de madurez varió entre 1067 y 1468 días; y la edad al 95% de madurez estuvo entre 2396 y 3322 días. Este estudo teve como objetivo descrever o crescimento de fêmeas cruzadas de seis grupos genéticos, utilizando o modelo de Brody. Os grupos genéticos foram: 50% Angus 50% Zebu (AZ), 50% BON 50% Zebu (BC), 100% Zebu (Z) 50% Romosinuano 50% Zebu (RZ), 50%Angus 25% Senepol e 25 % Zebu (SAZ), 50% Zebu e 50% Senepol (ZC). Foi estimada a percentagem de maturidade aos 12, 18 e 24 meses e a idade ao 75% e 95% de maturidade. A madures aos 12 meses oscilou entre 42% e 48.5%, para 18 entre 53% e 60%, e 24 meses entre 61% e 69%, o mais antigo grupo genético e da AC foi menos precoce BC. A idade variou de 75% vencimento entre 1067 e 1468 dias, e idade de maturidade foi de 95% entre 2396 e 3322 dias. The aim of this study was to describe the growth of crossbred females of six genetic groups using the model of Brody. Genetic groups evaluated were: 50% Angus 50% Zebu (AZ), 50% BON 50% Zebu (BZ), 100% Zebu (Z), 50% Romosinuano 50% Zebu (RZ), 50%Senepol 25% Angus 25% Zebu (SAZ), and 50% Senepol 50%Zebu (SZ). The percent of maturity at 12, 18, and 24 months and ages at 75% and 95% of maturity was estimated. The maturity at 12 months varied between 42% and 48.5%, at 18 months between 53% and 60%, and at 24 months between 61% and 69%. The genetic group more precocious was AZ, and less precocious was BZ. The age at 75% of maturity varied between 1067 and 1468 days; and age at 95% of maturity varied between 2396 and 3322 days.
Pedigree analysis on the population of Gir cattle in Northeast Brazil
Oliveira, Aracele Prates de;Malhado, Carlos Henrique Mendes;Carneiro, Paulo Luiz Souza;Martins Filho, Raimundo;Silveira, éderson Silva;Souza, Laaina de Andrade;Muniz, Lorena Mirelle Santos;Azevêdo, Danielle Maria Machado Ribeiro;
Revista Brasileira de Zootecnia , 2012, DOI: 10.1590/S1516-35982012000500011
Abstract: the objective of this study was to characterize the population genetic structure of the gir breed in the northeast of brazil. the data used in this study were taken from pedigree information of 8,897 gir animals between 1957 and 2007, obtained from the brazilian zebu breeders association (abcz). the program endog was used to estimate the parameters based on the probability gene origin. from the amount of the studied animals, 67.22%, 18.41% and 3.15% had complete pedigree only on the first, second and third parentage, respectively. the number of ancestors that contributed for the reference population was 2,755, of which only 171 explain the 50% genetic variability of the population. the actual number of founder herds was 168 and the effective number of founder herds was 22.3. the number of sire supplier herds was 22.16, 8.66 and 5.36 for fathers, grandfathers and great-grandfathers, respectively. the average coefficient of relatedness was estimated at 0.22%; the highest individual coefficient was 1.49%. the little variability of the current population is a result of the small number of effective founders and ancestors indicating the population evolved from a narrow genetic base.
Degenerative progressive hereditary mieloencefalopathy (Weaver Syndrome) in Gir calves
Oliveira, Pedro Carlos Lucas de;Coelho, Humberto Eustáquio;Medeiros, Alessandra Aparecida de;Rieck, Susana Elisa;Souza, Juliana Meirelles de;Alvarenga, Rodrigo Rodrigues;
Ciência Rural , 2008, DOI: 10.1590/S0103-84782008000100026
Abstract: degenerative progressive hereditary mieloencefalopathy is a disease described in young brown swiss cattle. in these animals the disease occurs in calves between six months and two years old showing mainly neurological signs. two zebu gir calves were examined at the veterinary hospital of uberaba, both with balance deficits. the neurological examination has shown that they were mentally alert, with appropriate conscience, head tremor, normal sensitive reflexes, normal sensitivity for superficial and deep pain, motor deficit of the pelvic limbs with severe ataxia. the calves were sacrificed. based on the clinical case and necroscopic and histopathological findings, it could be suggested that the neuropathy, which affected both animals described above, is very similar to the degenerative progressive hereditary mieloencefalopathy observed in brown swiss calves.
Associa??o do loco BoLA-DRB3.2 com produ??o de leite em bovinos da ra?a Gir
Machado, M.A.;Nascimento, C.S.;Martinez, M.L.;Silva, M.V.G.B.;Campos, A.L.;Teodoro, R.L.;Verneque, R.S.;Guimar?es, S.E.F.;
Arquivo Brasileiro de Medicina Veterinária e Zootecnia , 2005, DOI: 10.1590/S0102-09352005000300017
Abstract: the association between bola-drb3.2 alleles identified by pcr-rflp and milk production in gir breed was studied using molecular and phenotypic data of 424 gir cows. genetic data consisted of animal genotypes for bola-drb3.2 alleles and 305-day-milk-yield. the association between bola-drb3.2 alleles and a putative qtl affecting the trait was investigated by mixed model with an animal model. bola-drb3.2 locus was found to be highly polymorphic in gir breed, showing seven alleles (bola-drb3.2*4, *8, *11, *19, *28, *41 e *48) that have not been yet described in zebu animals. two bola-drb3 alleles (*16 e *29) were significantly associated with milk production, suggesting that bola-drb3.2 locus itself or a linked qtl influences 305-day-milk yield of gir cows.
Eficiência produtiva e reprodutiva em vacas leiteiras
Leite, Tisa Echevarria;Moraes, José Carlos Ferrugem;Pimentel, Cláudio Alves;
Ciência Rural , 2001, DOI: 10.1590/S0103-84782001000300017
Abstract: the present study was conducted to evaluate the effects of post partum disorders on productive and reproductive performance of holstein cows, from a dairy experimental station, during 24 years. productive and reproductive data were collected from 350 cows. analyses of variance was conducted to evaluate the effects of occurrence of post partum disorders (abortion, stillbirth, dystocia, retained placenta) and mastitis on calving interval (iep), calving to conception interval (ipc), calving to first estrus interval (ippc), number of estrus before conception (nc) and milk production (pl). the mean age at first estrus was 29.4 months and the mean age at first calving was 37.1 months. mean iep was 14.6 months, mean ippc was 97.04 days and median ipc was 150.71 days. median interestrus interval was 24 days, suggesting problems in a estrus detection. a significant effect of occurrence of abortion (p<0.05) was observed on iep. calving intervals were 258 days longer in the cows that aborted than in the ones that did not abort. the occurrence of stillbirth (p<0.01) and dystocia (p<0.05) significantly increased iep in 82.4 days and 136.1 days, respectively. the ippc was not affected by any of the diseases considered. milk production was affected by dystocia (p<0.05). cows that had dystocia produced 380.5kg less milk than normal calving cows. we concluded that preventive procedures to control herd health, criterious clinical diagnosis of post partum disorders and development of data bases with precise recordings for regular analysis of the productive and reproductive parameters may lead to a more economic dairy production.
Follicular dynamics in zebu cattle
VIANA, JO?O HENRIQUE MOREIRA;FERREIRA, ADEMIR DE MORAES;Sá, WANDERLEI FERREIRA DE;CAMARGO, LUIZ SéRGIO DE ALMEIDA;
Pesquisa Agropecuária Brasileira , 2000, DOI: 10.1590/S0100-204X2000001200021
Abstract: the aim of this study was to investigate the follicular dynamics during estrous cycle in gir breed (bos indicus) cows. follicular growth and atresia during estrous cycle were evaluated using a portable ultrasound device. luteal activity was evaluated by serum progesterone levels. cycles with two (6.67%), three (60.00%), four (26.67%) and five (6.67%) follicular waves were observed. there was no difference (p>0.05) in dominant or subordinate follicles growth or atresia rates among follicular waves. the maximum diameter of the ovulatory follicle was higher than the diameter of the other dominant follicles in cycles with four waves, and higher than the diameter of the second dominant follicle in cycles with three waves (p<0.05). there was no difference (p>0.05) in estrous cycle length (21.11±1.76 and 22.25±1.71 days) or progesterone levels during diestrous (4.48±1.45 and 5.08±1.40 ng/ml) between cycles with three or four waves. follicular dynamics in gir cattle is characterized by a higher incidence of cycles with three or four waves, associated with a low persistence of the dominant follicle.
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