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171.
L K Fox J A Nagy J K Hillers J D Cronrath D A Ratkowsky 《American journal of veterinary research》1991,52(6):799-802
Sixteen Holstein cows were used to test the effect of postmilking teat treatment on colonization and intramammary infection by Staphylococcus aureus on chapped teats. Treatments were (1) chapping the teat and using 1% I2/10% glycerin postdip solution, (2) 1% I2/10% glycerin postdip solution on nonchapped teats, (3) chapping the teat and using 10% glycerin postdip solution, (4) chapping the teat and not using a postdip solution. All mammary glands were free of S aureus teat skin colonization and intramammary infection at the start of the study. Teats selected for chapping were dipped in 1N NaOH prior to 3 applications of S aureus broth culture; cultures were applied at 12-hour intervals on all teats. Treatments were applied after each milking for 30 days and were initiated after the second broth dip. Teat skin swab specimens and milk samples were collected before treatment application. Teat skin condition was scored daily. Nonchapped teats (treatment 2) did not support skin or orifice colonization by S aureus. Treatment-1 teats healed most rapidly and supported less colonization in skin and orifice than did treatment-3 and -4 teats. Teat skin scores and skin colonization were lower for treatment-3 than treatment-4 teats. A correlation between teat skin colonization and teat skin conditions was found. Two intramammary infections were found in treatment-4 quarters and 1 in a treatment-3 quarter.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Rowell JE Lupton CJ Robertson MA Pfeiffer FA Nagy JA White RG 《Journal of animal science》2001,79(7):1670-1674
In response to increasing commercial interest and the high market value of qiviut (the downy underwool of the muskox), we have employed standards and measurements used in the wool and cashmere industries to describe qiviut fiber characteristics. Fleece samples (qiviut with guard hair) were shaved from the midshoulder of 299 wild muskox hides of known sex and age (1, 2, 3, and 4+ yr) during the Banks Island, Canada, muskox harvest in November 1997. Samples were analyzed for fiber diameter distribution of raw fiber and qiviut, scoured and qiviut yields, and lengths of guard hair and qiviut fiber. We found a sex x age interaction for average fiber diameter (AFD) in raw fiber (P= 0.002) and qiviut (P < 0.001) only. Adult males had significantly coarser AFD than females (21.5 microm, males vs 20.1 microm, females and 18.2 microm, males vs 17.5 microm, females) for raw fiber and qiviut, respectively. Qiviut AFD from yearlings was 1.7 microm finer than the AFD of adult qiviut. Fiber diameter distribution (SD) decreased with age in the raw sample (P < 0.003) and qiviut (P < 0.001) and qiviut SD was greater (P < 0.001) in males than in females. Qiviut theoretical yield (% mass of fibers < or = 30 microm) increased (P < 0.001) with age, and females had higher theoretical yields than males (P < 0.001). Scoured yield did not vary between sexes in any age class and averaged 93.3%. Qiviut staple length did not differ with either age or sex. In summary, differences between the sexes were small up to the 3rd yr, and these differences were not likely to be of commercial importance. However, considering that AFD is a primary commercial criterion of value, AFD changes from 16.5 microm in yearlings to 18.2 microm in adults and from 17.5 microm in adult females to 18.2 microm in adult males would be expected to result in significant differences in commercial value. 相似文献
176.
Unsupplemented porcine colostrum and milk exhibited a powerful bactericidal effect for porcine strains of E coli incubated in vitro at 37 degrees C. This activity was independent of complement but was susceptible to acid pH, to the presence of soluble iron and to the selective immunoprecipitation of IgG, IgA and IgM. Manifestation of bactericidal activity required bacteria in an active state of metabolism and the length of incubation was an important factor in demonstrating the quality of the anticoli activity, ie, proliferation-inhibitory, bacteriostatic or bactericidal. Whey obtained by acid precipitation or by the application of rennin was devoid of bactericidal activity but was capable of slowing down proliferation of E coli. There was no correlation between lysozyme and anticoli activity although the complete removal of lysozyme by adsorption on to bentonite reduced bactericidal titres. With very few exceptions the highest bactericidal titres were recorded for colostrum, but even 28 days post partum about one half of 22 undiluted milk samples exhibired bactericidal activity. 相似文献
177.
The analysis was conducted on the national database of the station tests carried out between May 1996 and February 2001, using the Hungarian Large White (LW) and Hungarian Landrace (LR) breeds, and the A-line of the Ka-Hyb hybrid (MLW). Days of test, total amount of feed consumed and valuable cuts were taken into the analysis to test the random distribution of the animals' phenotypic measurements and predicted breeding values across the contemporary groups of origin. The phenotypic measurements of all traits were clearly positively associated with the herds of origin (b = 0.52-1.08). Animals with favourable phenotypic measurements originated from better herds. On the contrary, the predicted breeding values seemed to be independent of the herd effects (b = -0.16-0.08) and suggested a possible random distribution across the contemporary groups. 相似文献
178.
Weaning weights of 442 beef calves (223 male and 219 female), born between 1997 and 2004 from cows of nine breeds (Hungarian Fleckvieh, Hereford, Aberdeen Angus, Red Angus, Lincoln Red, Charolais, Limousin, Blonde d' Aquitaine and Shaver) and maintained in the same conditions on peat-bog soil pasture at Keszthely, were evaluated. The effect of breed, age of dam, year/season of birth and sex of calf on the 205-day weaning weight was computed by analysis of variance (GLM). Overall mean of the 205-day weaning weight of all calves was 193 kg. The contribution to the total phenotypic variance of the 205-day weaning weight was: 18.60% by breed, 2.79% by age of dam, 43.23% by birth year, 3.95% by birth season and 31.43% by sex of calf. The evaluated factors had a significant (P < 0.05) effect on 205-day weight. Mean values by breeds were 198, 163, 206, 205, 182, 204, 181, 189 and 204 kg, respectively. According to the age of the dam, the weaning weight increased up to 5 years and after the maximum (205 kg) decreased. The minimum values were found in the group of 2- (178 kg) and 12-year-old (174 kg) cows. With respect to birth year, the highest weaning weight (238 kg) was observed in 2002 and the lowest (151 kg) in 1999. For birth season, winter, spring, summer and autumn, the 205-day weaning weight was 183, 196, 203 and 190 kg, respectively. Male calves reached 202 kg and female calves 185 kg mean value of the adjusted weaning weight. 相似文献
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