977 resultados para 305-day lactation yield


Relevância:

30.00% 30.00%

Publicador:

Resumo:

Data concerning daily milk yield (MY), percentage of milk fat (%F), protein (%P), lactose (%LT), and total solids (%TS), and somatic cell counts (SCC) for a herd of 222 Murrah buffalo reared in the state of São Paulo, Brazil, were collected monthly from 1997 to 2000 in order to study the factors affecting SCC and their relation to milk production and constituents during lactation. SCC decreased in the second month of lactation and increased thereafter, up to the ninth month of lactation. The interaction of month of lactation x order of calving was significant. Mean MY observed during the first month of lactation was 6.87 kg, which increased to 7.65 kg during the second month, and then decreased until the ninth month of lactation (3.83 kg). During the different months of lactation, %F, %P, %LT, and %TS ranged from 6.28 to 8.38%, 4.05 to 4.59%, 4.96 to 5.34%, and 16.94 to 18.55%, respectively. Calving year, calving order, and order of month of lactation significantly affected MY, %F, %P, %LT, and %TS. The regression coefficients of transformed SCC on MY and %LT were negative and significant during all months of lactation, showing that milk and lactose yield decreased with increased transformed SCC, causing losses to buffalo milk producers.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Descriptive herd variables (DVHE) were used to explain genotype by environment interactions (G x E) for milk yield (MY) in Brazilian and Colombian production environments and to develop a herd-cluster model to estimate covariance components and genetic parameters for each herd environment group. Data consisted of 180,522 lactation records of 94,558 Holstein cows from 937 Brazilian and 400 Colombian herds. Herds in both countries were jointly grouped in thirds according to 8 DVHE: production level, phenotypic variability, age at first calving, calving interval, percentage of imported semen, lactation length, and herd size. For each DVHE, REML bivariate animal model analyses were used to estimate genetic correlations for MY between upper and lower thirds of the data. Based on estimates of genetic correlations, weights were assigned to each DVHE to group herds in a cluster analysis using the FASTCLUS procedure in SAS. Three clusters were defined, and genetic and residual variance components were heterogeneous among herd clusters. Estimates of heritability in clusters 1 and 3 were 0.28 and 0.29, respectively, but the estimate was larger (0.39) in Cluster 2. The genetic correlations of MY from different clusters ranged from 0.89 to 0.97. The herd-cluster model based on DVHE properly takes into account G x E by grouping similar environments accordingly and seems to be an alternative to simply considering country borders to distinguish between environments.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Aiming to compare milk yield, residual milk and behavioral responses of Holstein cows during milking, fourteen experimental cows were mechanically milked twice a day, and evaluated during the first six weeks of lactation. Milk yield was measured daily, and residual milk volume weekly. Body (ribs region), udder and teat temperatures and respiratory frequency were measured twice a week. Animal behavior at the milking parlor was registered using ethograms and interviews with the milkers. During the first weeks of lactation, a higher percentage of kicks, over-steps, milking cups being knocked down, urinations and vocalizations in primiparous cows (p < 0.05) was observed, which were also considered more reactive by the parlors compared to multiparous cows. Multiparous cows produced more milk than primiparous (p < 0.05). However, there were no significant differences in residual milk percentage (p > 0.05), which suggests adaptation of both groups to the milking environment.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

In the present study, data of 1,578 first lactation females, calving from 1985 to 2006 were analysed with the purpose of estimating genetic parameters for milk yield (MY), age at first calving (AFC) and interval between first and second calving (IBFSC) in dairy buffaloes of the Murrah breed in Brazil, Heritability estimates for MY, AFC and IBFSC traits were 0.20, 0.07 and 0.14, respectively. Genetic correlations between MY and AFC and IBFSC were -0.12 and 0.07, respectively, while the corresponding phenotypic correlations were -0.15 and 0.30, respectively. Genetic and phenotypic correlations between AFC and IBFSC were 0.35 and 0.37, respectively. Genetic correlation between MY and AFC showed desirable negative association, suggesting that daughters of the bulls with high breeding values for MY could reach physiological mature at a precocious age. Genetic correlation between MY and IBFSC, showed that the selection for milk production could result in the increase of calving intervals.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

In the last decades several hormonal treatments to induce multiple ovulation and embryo transfer (MOET) have been developed. Tight control of the time of ovulation allowed the use of fixed-time artificial insemination (FTAI) in embryos donors, facilitating animal management. Although, protocols that allow FTAI have evolved and yield as much embryo as conventional protocols that requires estrus detection, substantial increase in viable embryo production has not been observed in superestimulated bovine cattle. The present mini-review put emphasis on superstimulatory protocols in which the last two doses of pFSH are replaced by eCG or LH. Recent results indicate that an extra LH stimulus (using eCG or LH), on the last day of P-36 superestimulatory treatment, seems to improve transferable embryo yield in both Bos taurus and Bos indicus cattle.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Application of sewage sludge with high lead (Pb) contents may pollute soils and contaminate crops. The objective of this work was to evaluate peanut responses to application of sewage sludge with varying Pb contents in order to supply phosphorus (P) to the plant. A greenhouse experiment was carried out with peanut grown on soil sample from a medium-textured Haplustox. Treatments were arranged in 3 × 2 + 2 factorial scheme, replicated three times, distributed in randomized block design, and consisted of: three Pb rates applied to soil with sewage sludge (3, 21, and 42 mg kg-1) × two times of sewage sludge application (30 days before peanut sowing and at the day of the sowing) + mineral fertilization + control (without sewage sludge and mineral fertilization). Sewage sludge was efficient to supply P to peanut. Sewage sludge containing high rates of Pb, when applied, did not harm biomass and yield of the plant, but increased HCl-extractable Pb in soil and Pb content in shoot, roots, and pod husks. Increase of Pb content in pod husks may represent contamination risk of kernels and their products with fragments from husks detached during manipulation or industrial processing of peanuts. © 2012 Fábio Camilotti et al.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

The objective was to evaluate the effect of unsaturated fatty acid sources supplementation on nutrients balances and milk fatty acid profile of mid lactation dairy cows. Twelve Brazilian Holstein cows in the mid lactation (mean of 128 days) and (580 ± 20kg of weight; mean ± SD) with milk yield of 25kg/d were assigned randomly into three 4 × 4 Latin square, fed the following diets: control (C); refined soybean oil; (SO); whole soybean raw (WS) and; calcium salts of unsaturated fatty acids (CSFA). Milk yield was 26.6; 26.4; 24.1 and 25.7 to the diets CO, SO, WS and CSFA respectively. Cows fed the WS treatment produced less milk (1.95kg/d of milk), fat and lactose than did cows fed the SO and CSFA. Cows fed the CSFA treatment showed less blood, urine (g/d) concentrations of N more energetic efficiency and intake of energy than did cows fed the SO treatment. Cows fed the unsaturated fatty acids sources showed more C18:2 cis-9, trans-11 CLA and trans-C18:1 FA concentration in milk than did cows fed the CO treatment. Diets with whole soybeans and soybeans oil provide more efficient digestive processes, and increase milk composition of unsaturated fatty acids.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

30.00% 30.00%

Publicador:

Resumo:

O objetivo deste trabalho foi estimar parâmetros genéticos para características produtivas, tais como: produção de leite (PL), produção de gordura (PG), duração da lactação (DL) e produção de leite por dia de intervalo de parto (PLDIDP) em búfalos (Bubalus bubalis) na Amazônia Oriental. O trabalho foi realizado na fazenda “Dr. Felisberto Camargo” de propriedade da EMBRAPA/CPATU, onde foram analisados registros produtivos colhidos no período compreendido entre 1967 a 2005. Foram analisados um total de 1.182 registros de fêmeas bubalinas da raça Murrah e seus mestiços. As médias observadas e os desvios-padrãopara PL, PG, DL e PLDIDP foram 1.663,84 ±343,60, 116,84 ±29,71, 269,89 ±56,36 e 3,88 ±1,15 respectivamente. Os parâmetros genéticos foram estimados por meio do método de Máxima Verossimilhança Restrita processada por meio de análises de bicaracterísticas, sendo as características como a produção de leite e gordura consideradas como efeitos fixos a época de parto, grupo genético e ordem de parto do animal, além da cováriavel duração da lactação. As estimativas de herdabilidade (h²) encontrada para as características PL, PG, DL e PLDIDP foram 0,25, 0,18, 0,08 e 0,09 respectivamente, com repetibilidade (r) para PL, PG e DL de 0,33, 0,29 e 0,10 respectivamente. As correlações genéticas entre as características foram 0,93(PL-PG), 0,76 (PL-DL), 0,99 (PL-PLDIDP), 0,89 (PG-DL), 0,87 (PG-PLDIDP) e -0,27 (DLPLDIDP). No rebanho estudado existe expressiva percentagem de animais que foram superiores geneticamente em relação à média da população para as características. Existe considerável variabilidade genética aditiva para as características estudadas, sendo que esta variabilidade pode ser utilizada para promover o melhoramento genético do rebanho.