Effects of neonatal vaccination on antigen-specific cellular and humoral immune responses of dairy calves have not been well described. The purpose of this study was to characterize the ontogeny of the adaptive immune response in calves sensitized to the attenuated strain of Mycobacterium bovis, bacillus Calmette-Guerín. Holstein bull calves were nonvaccinated (n = 6, vaccination controls) or v...

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...

Bovine tuberculosis (bTB) is highly prevalent in intensive dairy farms of the urban "milk-sheds" in Ethiopia, and vaccination could be a cost-effective disease control strategy. In the present study, the efficacy of Bacillus Calmette-Guerin (BCG) to protect against bTB was assessed in Holstein-Friesian calves in a natural transmission setting. Twenty-three 2-week-old calves were subcutaneously ...

An animal feeding trial was conducted on 18 seven-day-old Holstein dairy bull calves weighing 42 ± 3 kg each. Calves were randomly assigned into three groups (n = 6 each). The dietary treatments were as follows: (1) milk and starter for the control group (MS), (2) supplementation of oat hay from week 2 on the basis of milk and starter (MSO2), and (3) supplementation of oat hay from week 6 on th...

BACKGROUND Thoracic ultrasonography (US) and bronchoalveolar lavage fluid (BALF) analysis are antemortem methods used to identify the lung lesions associated with bovine respiratory disease (BRD). Accuracy of US and the cell distributions in BALF have not been characterized in calves with subclinical disease. OBJECTIVES To evaluate the accuracy of US and BALF and describe BALF characteristics...

BACKGROUND Bovine respiratory disease (BRD) remains among the leading causes of death of cattle internationally. The objective of this study was to identify risk factors associated with exposure to BRD pathogens during the peri-weaning period (day (d)-14 to d 14 relative to weaning at 0) in dairy bull calves using serological responses to these pathogens as surrogate markers of exposure. Clinic...

Effects of three different handling aids on calf behavior were determined. Group 1 calves were intensively-reared intact Holstein males (mean 180 days old); Group 2, extensively-reared beef-breed females (mean 230 days); Group 3, extensively-reared castrated beef-breed males (mean 253 days). Calves in each group were assigned to one of three handling aid treatments (n=5 per treatment subgroup; ...

OBJECTIVE To evaluate the effect of nutritional plane on health and performance of dairy calves after infection with Cryptosporidium parvum. DESIGN Randomized, controlled trial. ANIMALS 20 Holstein bull calves. PROCEDURES Calves were assigned to a higher plane of nutrition (HPN; 0.30 Mcal intake energy/kg of metabolic body weight using a 28% protein-20% fat milk replacer) or conventional ...

The purpose of the study was to determine if immunization with a recombinant protein (rC7) of Cryptosporidium parvum would induce immune bovine colostrum that protected calves against cryptosporidiosis following oral challenge with C. parvum oocysts. Late gestation Holstein cows with low titers of antibody to the p23 antigen of C. parvum were immunized three times with 300 microg affinity purif...

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...