The purpose of this study was to determine whether gamma-irradiated Cryptosporidium parvum oocysts could elicit protective immunity against cryptosporidiosis in dairy calves. Cryptosporidium parvum Iowa strain oocysts (1 x 10(6) per inoculation) were exposed to various levels of gamma irradiation (350-500 Gy) and inoculated into 1-day-old dairy calves. The calves were examined daily for clinica...

J. Anim. Sci. Vol. 88, E-Suppl. 2/J. Dairy Sci. Vol. 93, E-Suppl. 1/Poult. Sci. Vol. 89, E-Suppl. 1 390 Effect of feeding polyphenols from pomegranate extract on health, growth, nutrient digestion, and immunocompetence of calves. M. C. Perdomo*1, R. A. Oliveira1, C. D. Narciso1, R. S. Bisinotto1, M. A. Ballou2, M. Dreher3, and J. E. P. Santos1, 1University of Florida, Gainesville, 2Texas Tech U...

A prospective cohort study was undertaken on two central California dairies, A and B, to estimate prevalence of congenital infection with Neospora caninum, to characterize temporal variation in prevalence, to determine if occurrence of congenital infection was associated with specific dam and calf attributes, and to estimate the effect of congenital infection on calfhood mortality. Of the 405 c...

a 1:1 matched case-control study of calves under 1 month of age was carried out by weekly visits to 7 dairy farms in mashhad from may 2008 to october 2008. fecal samples were collected from a total of 112 calves with clinical signs of diarrhea and from 112 matched animals without clinical signs of diarrhea as assessed by a scoring system. the samples were investigated for the presence of rotavi...

Cryptosporidium parvum oocysts were detected in feces of dairy calves raised in Rio de Janeiro State and the risk factors involved in the infection were determined. A hundred calves aging up to 12-month-old from 13 dairy farms were sampled. Polymerase chain reaction was used to detect the presence of oocysts. The zoonotic C. parvum species was detected in 45% animals. Statistical risk factors a...

The objective of this study was to examine the effects of predictable vs. unpredictable management routines on the behaviour, production and health of dairy calves. Three different feeding schedules for milk-fed dairy calves were compared. All calves received milk twice a day, and had free access to concentrate, hay and water. Three groups of 12 calves (divided on two trials) were exposed to on...

The objective of this experiment was to determine the effect of lactoferrin (Lf) supplementation of colostrum replacer (CR) fed as 1 or 2 doses on apparent efficiency of IgG absorption, serum IgG concentrations, and xylose absorption/intestinal development in neonatal Holstein bull calves. Eighty bull calves were assigned to a 2 x 4 factorial arrangement of treatments in a randomized complete b...

The aims of the current study were to estimate the prevalence of enteropathogens in calves in Norwegian dairy herds, evaluate the clinical consequences of protozoal infections, and identify risk factors for diarrhea. The 135 participating herds were randomly selected from those in The Norwegian Dairy Herd Recording System that had at least 15 cow-years. Each herd was followed for 1 yr. Fecal sa...

Dehorning dairy calves is a necessary practice that should be conducted as early as possible and with appropriate anesthetic/analgesia. With the possible exception of caustic paste, calves perceive and react to acute pain during dehorning when no local anesthetic is used. Additional analgesia has been shown to be beneficial in calves dehorned at or beyond eight weeks of age. A routine dehorning...

The protective effect of a combined rotavirus/enterotoxigenic E. coli K99 vac­ cine against naturally occurring neonatal diarrhoea was evaluated in two dairy and two beef herds. Before vaccination, frequency of diarrhoea in these herds was 46% up to 60% with losses of 7% to 20%. After vaccination of pregnant cows and heifers mild diarrhoea occurred in 14% to 20% of their calves, one out of 144 ...