Objectives were to evaluate the associations between residual dry matter (DM) intake (RFI) and N (RNI) in early lactation, from 1 5 wk postpartum, mid 9 15 assess production performance risk of diseases cows according RFI lactation. Data 4 experiments including 399 Holsteins used this study. Intakes DM N, yields milk components, body weight, condition evaluated daily or weekly for first 105 d p...

The overall twinning rate was shown to increase from .6% in the first parity to 4.0% in the sixth parity, and a positive phenotypic trend for twinning rate was observed during the time period considered (1978 to 1995). The distribution of bulls according to the average percentage of multiple births of daughters in first and second parity showed that some bulls had an extremely low twinning freq...

Genomic evaluations are calculated using deregressed predicted transmitting abilities (PTA) from traditional evaluations to estimate effects of single nucleotide polymorphisms. The direct genomic value (sum of an animal's marker effects) should be consistent with traditional PTA, which is the case for bulls. However, traditional PTA of yield traits (milk, fat, and protein) for genotyped cows ar...

Sample day records of means of somatic cell scores were analyzed to develop adjustments to standardize records for length of lactation. Estimates for effect of DIM were from a model that included random lactation and cow effects for lactations to date of 753,929 Holsteins and 21,842 Jerseys calving in Pennsylvania or Wisconsin from 1987 to 1991. Lactation, cow, and residual variances were estim...

Inbreeding coefficients are calculated routinely for all animals included in national genetic evaluations for yield traits. The base population for inbreeding is defined as animals born during 1960. Animals with unknown parents are assumed to have inbreeding coefficients that are equal to the mean of coefficients for animals with known parents born during the same year. Mean inbreeding coeffici...

Genomic evaluations of dairy cattle in the United States have been available for Brown Swiss, Holsteins, and Jerseys since 2009. As of January 2013, 1,023 Ayrshires had genotypes in the North American database. Evaluation accuracy was assessed using genomic evaluations based on 646 bulls with 2008 traditional evaluations to predict daughter performance of up to 180 bulls in 2012. Mean gain in r...

The objectives were to estimate the effects of various environmental factors on female calf survival Israeli Holsteins, economic value under conditions, genetic and variance components for cow using individual animal model, perform GWAS analyses first calving herd life after calving, trends since 1985, correlations with traits included in current breeding index, consequences inclusion national ...

Milk production in Thailand has been growing into an important agricultural sector, but it still faces numerous difficulties in environmental constraints. The main intention of this study was to identify significant environmental effects on production and fertility traits to give advices for farm management. Additionally, adjusting records for environmental impact is essential to define appropr...

a total of 136,250 monthly test day milk records collected from 13,625 iranian holstein heifers (three times a day milking) calved between 1991 and 2001 and distributed over 264 herds were used to study the effects of some environmental factors influencing lacta-tion curve parameters as well as production characteristics. wilmink’s function (yt = w0 + w1t + w2e-0.05t) was fitted to individual l...