Thirty healthy Murrah buffalo (Bubalus bubalis) in their second to fourth lactations were selected from the herd at the National Dairy Research Institute, Karnal, Haryana, India, for use in a 35-d study to determine the effects of recombinantly produced bovine somatotropin on milk production, milk composition, and dry matter intake. Treatments were daily injections of 0, 25, or 50 mg somatotropin per animal for 14 d. All buffalo consumed green chopped fodder ad libitum plus a predetermined quantity of concentrate mixture to each animal, based on individual milk production during the 14-d pretreatment period. The quantity of concentrate mixture fed to each buffalo was not altered during the study. Net increase in milk volume for groups receiving 25 and 30 mg somatotropin was 16.8 and 29.5% over controls. Milk composition, DM intake, and body weights were not affected by treatment.
SUMMARYFor the cultivation of avian reoviruses a comparison was made of cell cultures of chick embryo fibroblasts, lungs, liver, kidney and chicken kidney and fertile eggs inoculated via the yolk sac, chorioallantoic membrane or allantoic cavity. Chick embryo liver was found to be the most sensitive cell culture method and the yolk sac the best inoculation route for eggs. Chicken kidney cells were second to embryonic liver cells, but peak titres of cell-bound and cell-free virus occurred later than in chick embryo liver.Using the plaque technique, minimal adsorption times for reovirus in embryonic liver and chicken kidney cells were found to be 30 and 45 min respectively. .Plaques produced by six different strains of reovirus in embryonic liver cells were larger and appeared sooner than in chicken kidney cells.
SUMMARYIn two experiments, 13 avian reoviruses from different sources were tested in specific pathogen-free (SPF) light hybrid chicks at 1-day-old for their pathogenicity with particular respect to tenosynovitis. All strains including two from commercial ducks and another from a wedge-tail eagle caused tenosynovitis. In most cases the lesions were macroscopic but in a few only microscopic abnormalities were observed after footpad or oral inoculation. In the first experiment with six British strains, infection by contact also resulted in tenosynovitis, and in most cases virus persisted longer in the hock joint/tendons than in the gut. Among the 13 viruses, two strains, R14 and Lasswade 126/75 were the mildest, producing only slight microscopic lesions of the disease, while strain WVU 2937 was the most virulent for joints/tendons.
Continuous programs of a combination of narasin (40 ppm) and nicarbazin (40 ppm) (NaNi), narasin at levels of 60 and 70 ppm, and a 2 by 2 factorial shuttle design (NaNi or nicarbazin at 125 ppm, each for 27 or 28 days, followed by narasin at 60 or 70 ppm to termination), were compared with unmedicated controls for their anticoccidial efficacy and growth performance in nine broiler trials conducted in seven countries outside the United States. Cecal coccidial lesions were reduced only by treatments that incorporated nicarbazin either at the 40-ppm level in NaNi or at 125 ppm, whereas total intestinal lesion scores were reduced by all the anticoccidial programs tested. At Day 28, the three treatments containing NaNi and the treatment containing narasin at 60 ppm significantly improved weight gain and feed efficiencies over the two treatments containing nicarbazin at 125 ppm and the unmedicated controls. At termination all the anticoccidial programs significantly decreased the mortality rate and improved bird weights and feed efficiencies. Birds on the treatments containing NaNi either in the two shuttle programs or in the continuous program were significantly heavier than those on the two treatments containing nicarbazin at 125 ppm in shuttle programs.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.