The decline of dairy cattle fertility worldwide remains a major concern, with conception rates to first service commonly below 40%. The length and severity of negative energy balance postpartum are unfavorably correlated with fertility, suggesting that the length and severity of negative energy balance and fertility are linked via several hormones or metabolites. These compounds therefore have ...

Male Holstein calves (n = 120) purchased from local dairy farms were fed one of three calf milk replacers for 42 d. Experimental milk replacers were formulated to contain whey protein concentrate (WPC) as the primary protein source or WPC plus 5% spray-dried bovine plasma (SDBP) or spray-dried porcine plasma (SDPP). The SDPP was heated to remove heat-insoluble materials and provide products wit...

To observe the effects of supplemental dietary d-α-tocopherol in relation to dietary energy on growth and immune status in dairy calves, 32 newborn Holstein bull calves were assigned to 1 of 4 treatments for 5 wk in a 2 × 2 factorial, randomized complete block, split-plot design. Calves received moderate growth (MG) or low growth (LG) all-milk dietary treatments, formulated to support daily gai...

in order to estimate the mean of maternal antibody in calves against bhv-1 (bovine herpes virus type 1), this study was carried out in a population of calves from non-vaccinated dairy cattle at 2 livestock in qazvin province. one hundred thirteen sera out of 512 were collected from 1-4 months unvaccinated calves. we used blocking –percentage of maternal antibodies against bhv-1, which obtained ...

Group housing provides increased access to space and social interactions for calves while reducing labor costs for producers. However, group housing necessarily requires that calves be mixed and no research to date has addressed the effects of mixing on behavior of milk-fed dairy calves. The objective of this study was to monitor the feeding and competitive behavior of individual dairy calves (...

Objectives. The prevalence of Cryptosporidium and the risk factors of zoonotic transmission in Najafabad, Isfahan, Iran dairy farms were examined. Methods. One fecal sample was collected from all calves less than 6 months old in eight dairy farms around Najafabad (Isfahan province, Central Iran) as well as individuals working in these farms and their household members. A two-step nested PCR pro...

BACKGROUND Previous studies have shown a high prevalence of failure of passive transfer of immunity (FPT) in Swiss dairy calves. OBJECTIVES To investigate risk factors associated with poor colostrum quality and FPT on Swiss dairy farms. ANIMALS Colostrum and serum samples from 373 dam-calf pairs at 141 farms. METHODS The gamma globulin (Gg) concentrations of the dams' colostrum and the ca...

JAVMA, Vol 230, No. 6, March 15, 2007 T US dairy industry is moving toward fewer dairy farms with more cattle per farm. Between 1995 and 2005, the number of dairy farms decreased by 43.9% (from 139,670 to 78,295), but the total number of milk cows decreased by only 4.5% (from 9.47 to 9.04 million). Consequently, the average herd size for dairies in the United States has almost doubled during th...

OBJECTIVE To determine the effects of 3 commercially available, orally administered electrolyte solutions (OAEs) on abomasal luminal pH and emptying rate in dairy calves, compared with the effect of orally administered milk replacer. DESIGN Randomized crossover study. ANIMALS 6 male dairy calves (age, 12 to 31 days). PROCEDURES Calves were surgically instrumented with an abomasal cannula ...

We investigated Clostridium difficile in calves and the similarity between bovine and human C. difficile PCR ribotypes by conducting a case-control study of calves from 102 dairy farms in Canada. Fecal samples from 144 calves with diarrhea and 134 control calves were cultured for C. difficile and tested with an ELISA for C. difficile toxins A and B. C. difficile was isolated from 31 of 278 calv...