A group 2 human coronavirus designated HECV-4408 was isolated from a child with acute diarrhea and is antigenically and genetically more closely related to bovine coronavirus (BCoV) than to human coronavirus OC43 (X. M. Zhang, W. Herbst, K. G. Kousoulas, and J. Storz, J. Med. Virol. 44:152-161, 1994). To determine whether HECV-4408 infects gnotobiotic calves and induces cross-protective immunit...

Permanent effects of early postnatal nutrition on the development and function of tissues and organs have been previously demonstrated primarily in humans and rodents. The objective of this study in calves was to analyze the impact of rearing conditions during the first 3 wk of life on morphology of insulin-producing pancreatic β-cells. Forty-two male Holstein calves were raised during the firs...

Faecal samples from 291 dairy calves from 10 dairy herds in Kerman were examined to investigate theprevalence of Cryptosporidium infection. Cryptosporidium spp. oocysts were identified by using themodified Ziehl-Neelsen staining technique in 63 (21.65%) calves. Calves were grouped according to theirage as follows:

The hypothesis that dietary L-arginine (L-Arg) supplementation would increase growth hormone (GH) secretion and antibody production in preruminant calves was tested. Sixteen newborn calves were randomly assigned to either Arg+ or Arg- treatment groups. Both groups were fed a single dose of Colostrx within 6 h after birth followed by milk replacer twice daily until weaning. Beginning with the Co...

The objective of the current study was to examine the effect of pasteurization of waste milk, used to feed dairy calves, on the bacterial diversity of their lower gut. Using 16S rDNA bacterial tag-encoded FLX amplicon pyrosequencing, fecal samples from dairy calves, ages 1 wk to 6 mo old and fed either pasteurized or nonpasteurized waste milk, were analyzed for bacterial diversity. Calves were ...

Blindness attributed to vitamin A deficiency afflicted 47 out of 197, and 15 out of 29 new-born dairy calves on 2 farms. Other clinical signs included doming of the forehead, thickening of the carpal joints, incoordination and weakness. Gross lesions in 8 of the calves examined consisted in hydrocephalus and thickened occipital and sphenoid bones. In 4 of these calves the optic nerves were cons...

A dairy herd including approximately 50 milking cows and 40 heifers and calves was investigated. This herd was detected with high prevalence of calves persistently infected (PI) with bovine viral diarrhea virus (BVDV). Nine PI animals including a milking cow and 8 newborn calves were detected in the herd within 4 months. Prevalence of PI animals in this herd was estimated 7.0% which was very hi...

OBJECTIVES To determine effects of selectin inhibitor TBC1269 on neutrophil infiltration, and neutrophil-associated injury during pneumonia induced by Mannheimia haemolytica and concentration of antimicrobial anionic peptide (AAP) in bronchoalveolar lavage fluid (BALF) as well as antimicrobial activity of BALF from healthy (control) neonatal calves, neonatal calves with M haemolytica-induced pn...

Weaned 3- to 4-month-old calves were fasted for 48 h, inoculated with 10(10) CFU of Shiga toxin-positive Escherichia coli (STEC) O157:H7 strain 86-24 (STEC O157) or STEC O91:H21 strain B2F1 (STEC O91), Shiga toxin-negative E. coli O157:H7 strain 87-23 (Stx(-) O157), or a nonpathogenic control E. coli strain, necropsied 4 days postinoculation, and examined bacteriologically and histologically. S...

Mannheimia haemolytica is a major bacterial component of bovine respiratory disease (BRD); unfortunately, very little is known about M. haemolytica transmission dynamics among cattle. Identifying potential variation in M. haemolytica populations over time and induction of nasopharyngeal colonization and subsequent shedding are 2 areas where knowledge is lacking. In our study, 2 separate loads o...