Performance, digestibility of nutrients, microbial nitrogen flow (MNF) and nitrogen efficiency (NE) inearly lactating Holstein cows were investigated by diet supplementation with sodium caseinate (CN).Multiparous lactating Holstein cows (n = 15) with an average body weight of 638 kg and 21 days in milkwere assigned to a completely randomized design (five cows per treatment) and fed a basal diet...

Investigation of Technical Efficiency and Economic Value Some Production, Reproductive, Survival Growth Traits Holstein Cows in Pars Agriculture Industry Ardabil Province

The aim of this study was to determine the factors affecting stillbirth and the consequences of stillbirth on longevity, production, and reproductive performance in Holstein cows of Iran. Calving records from March 2000 to April 2009 comprising of 220,043 calvings on 102,199 cows in 33 herds were used. The results showed that 4.06% of the newborn calves died within 48 h of birth. The stillbirth...

The objective of this work was to obtain prevalence estimates of cloudy vaginal mucus in artificially inseminated Holstein cows raised under intense heat, in order to assess the effect of meteorological conditions on its occurrence during estrus and to determine its effect on conception rate. In a first study, an association was established between the occurrence of cloudy vaginal mucus during ...

We investigated the effect of stage of pregnancy on estimates of breeding values for milk yield and milk persistency in Gyr and Holstein dairy cattle in Brazil. Test-day milk yield records were analyzed using random regression models with or without the effect of pregnancy. Models were compared using residual variances, heritabilities, rank correlations of estimated breeding values of bul...

Bovine leukocyte antigen DRB3 alleles from Holstein x Zebu crossbred dairy cows (n = 409) were analyzed using the PCR-RFLP technique. Exon II of DRB3 was amplified using locus-specific primers (HLO30/HLO32), followed by digestion with 3 restriction enzymes (RsaI, BstyI, and HaeIII). Forty alleles were found with frequency ranging from 0.005 to 0.139. The most frequently detected alleles of Hols...

Increased Milk Production, Concentration of Unsaturated Fatty Acids and Conjugated Linoleic Acid in the Holstein Lactating Cows using Monensin

The study aimed to determine factors affecting the dry period length and effect of dry days on milk yield, milk composition and lactation length in the next lactation of dairy cows. Data used for analysis included 7264 lactation records collected from 2012 to 2016 on 4737 Holstein cows raised in 152 herds. The statistical model used to determine the factors influencing the dry period length sho...

1 SUMMARY In this study ten machine milked cows (MM) and ten suckled +hand milked (HM) Holstein cows were studied for plasma lipid concentrations. Used blood samples were collected from the jugular vein of the cows on the last day of the second (2 and fourth (4 week of the early lactation period.Total lipid levels were lower in MM treatment for second and fourth week (P<0.05) but triglyceride a...

Charolais sires can be mated to Montbéliard or Holstein dairy cows to produce crossbred calves sold for meat production. Heritabilities and correlations between traits can differ when they are calculated within Charolais × Montbéliard or within Charolais × Holstein population. Moreover, the genetic correlation between the same trait measured on Charolais × Montbéliard and on Charolais × Holstei...