and Implications The relationships between body condition score (BCS) observed during the first 45 days of lactation and two measures of feed efficiency, residual feed intake (RFI) and gross efficiency (GE) defined as milk energy / DMI, measured during mid-lactation were assessed in 255 first lactation Holstein cows. No significant differences in BCS at calving and at approximately 40 days in m...

We conducted three experiments to determine the effects of dietary thiamin supplementation on milk production by dairy cows. In trial 1, 28 Holstein cows were blocked by parity and assigned randomly to either placebo or thiamin top-dress for the 8-wk experiment to provide a supplemental thiamin intake of 0 or 150 mg/d per cow. Within each of these groups, cows were further assigned randomly to ...

In pasture-based seasonal calving systems, failure to become pregnant during the breeding season results in important economic losses as maximum profit is attained by minimising costs and increasing the proportion of grass in the diet of the lactating dairy cow. In the United States, dairy producers primarily strive to maximise production potential but are becoming increasingly aware of the eco...

First-parity Holstein (H), Normande-Holstein (NxH) crossbred, Montbeliarde-Holstein (MxH) crossbred and Scandinavian-Holstein (SxH) crossbred cows calving from June 2001 to December 2003 were compared for dystocia and stillbirths from seven California herds. Dystocia scores ranging from 1 (no assistance) to 5 (hard pull) and stillbirths (1 for alive and 0 for dead) were recorded for 1695 Holste...

polymorphism of the b-lactoglobulin (b-lg) gene in 101 cows belonging to the holstein herd and a superior cow, producing more than 150 kg milk/day, together with four offsprings was investigated by the polymerase chain reaction-restriction fragment length polymorphism (pcr-rflp) method. in the holstein herd, the alleles a and b of the b-lg gene had frequencies of 0.53 and 0.47, respectively. th...

BACKGROUND The dairy industry has undergone substantial structural changes as intensive farming has developed during recent decades. Mastitis continues to be the most common production disease of dairy cows. Nationwide surveys of mastitis prevalence are useful in monitoring udder health of dairy herds and to study the impact of structural changes on the dairy industry. This survey on bovine sub...