Ten crossbred sows were used per treatment to determine production and composition of milk and litter growth. Treatment 1 consisted of a basal diet plus animal fat from d 109 of gestation until farrowing, then only the basal diet through lactation. Treatment 2 was the same level of basal diet plus animal fat from d 109 of gestation to d 21 of lactation. Treatment 3 was the basal diet plus corns...

Plant essential plant oils (EO) are volatile aromatic compounds with antimicrobial activity that can alter ruminal fermentation when used as dietary supplements. A feeding trial was conducted to determine the effects of dietary supplementation of periparturient and early lactation dairy cows with a specific mixture of EO. Forty multiparous Holstein cows were randomly assigned to either control ...

the fixed regression test-day model (frm) and random regression test-day model (rrm) for genetic evaluation of milk yield trait of dairy cattle in khorasan razavi province were studied. breeding values and genetic parameters of milk yield trait from two models were compared. a total of 164391 monthly test day milk records (three times milking per day) obtained from 19217 holstein cows distribut...

Many governments have signed up to greenhouse gas emission (GHGE) reduction programmes under their national climate change obligations. Recently, it has been suggested that the use of extended lactations in dairy herds could result in reduced GHGE. Dairy GHGE were modelled on a national basis and the model was used to compare emissions from lactations of three different lengths (305, 370 and 44...

Milk yield, milk flow, and udder morphology traits were measured in 72 East Friesian crossbred multiparous ewes to estimate the variation in milk flow patterns present in this research flock, and to asses the repeatability of these measurements and their relationships with other lactation traits. A special milk flow apparatus designed for dairy ewes was used on two consecutive morning milkings ...

Early lactation parameters are difficult to estimate from commercial dairy records due to the small number of records available before the peak of production. A biological model of lactation was used with weekly milk records from a single Holstein herd to estimate these early lactation parameters and the secretion rate of milk from the average cell throughout lactation. A genetic analysis of th...

Survival analysis in a Weibull proportional hazards model was used to evaluate the impact of somatic cell count (SCC) on the involuntary culling rate of US Holstein and Jersey cows with first calvings from 1990 to 2000. The full data set, consisting of records from 978,043 Holstein and 250,835 Jersey cows, was divided into subsets (5 for Holsteins and 3 for Jerseys) based on herd average lactat...