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91.
Lyophilised serum offers significant advantages over frozen serum when it comes to shipping such material over long distances. Babesia bigemina and B bovis were cultured in medium supplemented by either frozen-thawed or lyophilised-rehydrated serum. There were no significant differences between the two types of medium in the growth of parasites and percentage of infected cells during subcultivation for 18 days. 相似文献
92.
The objective of these experiments was to examine methods of modifying the fatty acid composition of bovine tissues. In the first experiment, four steers were fitted with duodenal fistulas and were assigned to four diets in a Latin square design. The steers were fed a control diet or the same diet containing 10% high-oleate partially crushed sunflower seeds, serum-coated sunflower seeds, and heat-treated, serum-coated sunflower seeds for 5 d. Samples of digesta and feces were collected on d 5. The inclusion of sunflower seeds (plain or serum-coated) in the diet increased (P less than .05) the digesta concentration of stearate. The percentage of stearate in the digesta and feces was increased (P less than .05) from 51 to 67% and from 64 to 74%, respectively, when steers were fed the untreated sunflower seed. The fecal concentration of oleate was increased (P less than .05) by dietary sunflower seeds in steers that were fed the serum-coated, unheated sunflower seeds. In a second experiment, heifers (four per group) were fed a corn-based control diet or diets containing 10% of high-oleate sunflower oil encapsulated with calcium alginate, either plain, coated with blood meal, or with blood meal integrated into the pellet. After 50 d on treatment, samples of perianal adipose tissue were obtained by biopsy. The fatty acid composition of the adipose tissue was not modified by the inclusion of the encapsulated oleate in the diet. In summary, limited ruminal bypass of sunflower seed oleate was accomplished with sunflower seed but not with encapsulated oleate. 相似文献
93.
94.
The relationship between the levels of CO and airborne Pb was evaluated against conditions of traffic flow, ambient air temperature and the ventilation rates in 3 underground car parks. During the study period significant variations were noted in the levels of the pollutants in each of the car parks which frequently exceeded the proposed Malaysian Air Quality Standard of 0.7 μg m?3Pb and 9 μg L?1 (8 hr average) CO for indoor environs. High correlation coefficient values were obtained between the levels of CO and traffic flow and Pb and traffic flow. High traffic flow also increased the mean air temperature inside the car parks. Reductions in the ventilation rates in the car parks caused an almost two-fold increase in the level of CO and vice versa. A simple mathematical model depicting the CO concentrations in relation to other parameters was formulated. 相似文献
95.
A tumor of the third eyelid gland was diagnosed in a 13 year old female Chihuahua. Histopathology of the excised tissue revealed an apocrine adnexoma with squamous metaplasia. The literature regarding prolapse and tumors of the third eyelid gland was reviewed. No case with similar morphology to this tumor was described to our knowledge. 相似文献
96.
M P Moore 《Veterinary Clinics of North America: Small Animal Practice》1992,22(4):1027-1034
The etiopathogenesis and diagnosis of discospondylitis are reviewed. Various therapy options are described. Also included is a discussion of the appropriate usage of specific antimicrobial agents. 相似文献
97.
Antibody responses to avian encephalomyelitis virus vaccines when administered by different routes 总被引:1,自引:0,他引:1
Antibody responses to a commercial avian encephalomyelitis virus (AEV) vaccine administered by different routes were measured by an enzyme-linked immunosorbent assay (ELISA). Responses to single doses of vaccine administered by the ocular route to 10% of a flock were comparable with those obtained when all birds received a single dose in the drinking water. However, ocular vaccination of 5% of the flock resulted in significantly lower responses than those obtained when 10% were vaccinated. Maternal antibody was shown by the ELISA to persist in chickens from vaccinated flocks for up to 21 days after hatching. Day-old chickens with serum absorbances of < 0.3 at 492 nm, as determined by the ELISA, were shown to be susceptible to intracerebral challenge with the neurotropic Van Roekel strain of AEV. 相似文献
98.
While isotopic techniques have largely superseded traditional markers for the determination of the volume of fluid compartments in vivo, they are not always convenient, especially with diarrhoeic animals. A direct comparison was therefore made in week-old calves between Evans blue and radio-iodinated serum albumin as measures of plasma volume and thiocyanate or 24sodium as measures of extracellular fluid space. The correlation coefficients were excellent (1.00, 0.96; P < 0.001) and the calves had plasma and extracellular fluid volumes of 72 +/- 2 and 438 +/- 2 ml kg-1, respectively. The latter value is, though high, typical of young animals and comparable with other data in calves. 相似文献
99.
Linear functions of body weight and condition score at weaning and 18 mo of age were used to predict the mature weight (A) and maturing rate (k) parameters of an asymptotic growth model of Angus cows at the Subtropical Agricultural Research Station, Brooksville, FL. From 1981 through 1988 a heavy-mature-weight line (Line A) and a rapid-maturing line (Line K) were selected based on predicted A and k values. Linear contrasts (A-K) of least squares means for weight at fixed ages indicated that the weight difference between lines increased from birth to maturity during the period of the study. Animals from Line A were heavier (P less than .01) at all ages. A negative response in maternal ability, relative to increased growth potential of their calves, seems to have occurred in the cows of Line A. Mature weight was reached at approximately 4.5 yr of age in Line K and at approximately 5.5 yr in Line A. Brody's three-parameter and Richards' four-parameter functions were fitted to 2,855 quarterly weights of cows, from birth to 6.5 yr of age, to estimate the average growth curve for each line. Brody's model gave better estimates of weights from 18 mo to maturity, but the asymptotic residual mean squares were slightly higher because early weights were overestimated. Linear and nonlinear regression analyses of weight-age data and comparisons of degree of maturity at different premature ages showed differences in the growth patterns of the two lines selected for early predicted values of A and k. 相似文献
100.
We tested hemolytic E. coli from 86 pigs with edema disease or colidiarrhea. They were tested serologically and with nonradioactive digoxigenin-dUTP labelled probes for the presence of enterotoxin or Shiga-like-toxin genes. By slide-agglutination we detected 38 cases with E. coli O149:K88, 28 with E. coli O139:82B and 20 with E. coli O141. E. coli of serogroup O149:K88 isolated from diarrheic pigs, reacted with the probes for LT and STb genes. Edema disease E. coli O139:82B reacted with the SLTII probe. E. coli O141, isolated from colidiarrhea or edema disease showed a diversity of toxin gene patterns. All the E. coli O141 from diarrheic pigs reacted with the probes for LT and STap in addition to SLTII. No strains isolated from pigs with edema disease possessed any of these enterotoxin genes. Gene probe technique confirmed the serological method as useful tool for diagnosing E. coli O149:K88 and O139:82B as ETEC or VTEC, respectively. On the other hand only the demonstration of toxin genes with probes could explain the pathological findings in the pigs shedding E. coli of serogroup O141. 相似文献