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961.
M C Smith 《Journal of the American Veterinary Medical Association》1979,174(12):1328-1332
Of six goats with polioencephalomalacia, three responded to thiamin therapy, whereas three died 2 to 7 days after onset of signs. The goats were 2 months to 2 1/2 years old. They were affected during the winter or early spring, and concentrate feeding was a prominent part of the history. Transketolase activity values were obtained from two affected goats and from nine controls. The affected goats had lower transketolase activity than any of the controls. 相似文献
962.
963.
A M Pope J E Heavner J A Guarnieri C P Knobloch 《Journal of the American Veterinary Medical Association》1986,189(7):781-783
The neuroteratogenicity of trichlorfon was evaluated in 3 groups of pregnant sows (8/group). The treatments were: control (no trichlorfon), trichlorfon (60 mg/kg of body weight) in the feed only on day 55 of gestation, or trichlorfon (60 mg/kg of body weight) in the feed on day 55 and day 70 of gestation. One week after farrowing, all newborn pigs were removed from the sows and were euthanatized. Brain and cerebellum weights of the newborn pigs were recorded. Mean cerebellum weights and cerebellum/total brain weight ratios of the neonatal pigs were 3.780 and 0.106 (group 1, n = 26), 3.183 and 0.098 (group 2, n = 42), and 2.986 and 0.088 (group 3, n = 61). Although trichlorfon interfered with cerebellar development and the severity of the trichlorfon-induced cerebellar hypoplasia was dosage-related, ataxia did not develop in the neonatal pigs. 相似文献
964.
Ten dairy cows were infused intramammarily near drying off with concanavalin A (conA) or phytohemagglutinin (PHA). Mammary secretions were collected during physiologic transitions of the udder and were used in an in vitro microbiological assay to determine growth inhibition of mastitis pathogens. As mammary involution progressed, in vitro growth inhibition of Klebsiella pneumoniae, Escherichia coli, and Streptococcus uberis increased. Mammary secretions from conA- and PHA-treated glands had significantly increased bacterial growth inhibition. Secretions contained significantly increased concentrations of lactoferrin and a decreased citrate:lactoferrin molar ratio earlier in the dry period than did control mammary secretions. Greatest bacterial growth inhibition was observed in mammary secretions obtained 7 days before parturition. However, differences in secretion composition or bacterial growth inhibition were not found between conA- or PHA-treated and control udder halves during the prepartum period. Bacterial growth inhibition by mammary secretion decreased markedly during early lactation. A highly significant positive correlation was found between bacterial growth inhibition and concentrations of lactoferrin, serum albumin, and immunoglobulin G. A highly significant negative correlation was found in the citrate:lactoferrin molar ratio during early involution and the peripartum period. 相似文献
965.
Spherocytes were detected on blood smears of 2 Angus cows. The RBC from both cows had increased fragility in hypotonic saline solution, supporting the presence of spherocytes. Other laboratory tests revealed a macrocytic, regenerative anemia with anisocytosis, polychromasia, basophilic stippling, Howell-Jolly bodies, nucleated RBC, and Anaplasma marginale organisms. A complement-fixation test was positive for anaplasmosis in cow 1 and a direct Coombs' test was positive for immunoglobulin G in both cows. 相似文献
966.
Four subsamples of meat and bone meal (MBM) were heated (150 degrees C) for 0, 1.5, 3 and 5 h and then incorporated into four individual diets (100 g MBM/kg diet). The diets were precision-fed to 10 caecectomised and 10 intact adult cockerels. The apparent amino acid digestibility (ApAAD) and true amino acid digestibility (TAAD) of the diets were determined by analysis of the excreta. The digestibility coefficients measured using caecectomised birds were lower than those determined with intact birds. Coefficients of digestibility were statistically examined by analysis of variance for the effects of bird type (caecectomised or intact), type of calculation (apparent or true) and diet (heat-treatment) with and without accommodation for individual bird variability. If individual bird variability was not considered in the analysis the bird type X diet interactions (P less than 0.01) included glutamic acid, tyrosine and serine. When individual bird variability was included in the analysis, significant (P less than 0.01) bird type X diet interactions occurred for aspartic acid, serine, glutamic acid, leucine, tyrosine and lysine and the precision of the data was markedly improved. Amino acid digestibility using the precision-feeding procedure is affected by the selection of either intact or caecectomised birds. 相似文献
967.
K L Esbenshade J H Britt J D Armstrong V D Toelle C M Stanislaw 《Journal of animal science》1986,62(5):1187-1193
Weight, heartgirth, backfat and body condition of sows was monitored in a commercial, farrow-to-finish unit during 1 yr. Measurements were obtained during the third, ninth and fifteenth week of gestation and the day after weaning. Litter performance and rebreeding rate also were recorded. Body weight and heartgirth increased (P less than .01) over parities because gestational gains were larger than lactational losses. Backfat tended to be lower in later parities. Body weight, heartgirth and backfat, but not condition score, declined from weaning to the third week of the subsequent gestation in both first and second litter sows. Correlations among measures of body condition were low (less than .45), except the overall correlation between body weight and heartgirth. Number of pigs born alive increased and interval to estrus decreased in later parities. There were no significant relationships between changes in body condition and rebreeding performance of sows. These results suggest that changes in body condition typically observed in sows housed in commercial production units may be too subtle to have an effect on reproductive performance. 相似文献
968.
969.
Characteristics of cerebrospinal fluid associated with canine granulomatous meningoencephalomyelitis: a retrospective study 总被引:2,自引:0,他引:2
Cerebrospinal fluid of 22 dogs with histologically confirmed granulomatous meningoencephalomyelitis was analyzed, retrospectively. Seventeen dogs had cisternal CSF analysis, 4 dogs had lumbar CSF analysis, and 1 dog had both. For cisternal CSF, the mean +/- SEM total WBC count was 800.8 +/- 300.9 cells/microliter. The WBC differential count was predominantly lymphoplasmacytic cells, but 13 of the 18 cisternal CSF had polymorphonuclear (PMN) cells, and the mean +/- SEM PMN cell percentage was 18.6 +/- 5.3%. The mean +/- SEM total protein content of cisternal CSF was 255.8 +/- 98 mg/dl. Of 5 cisternal CSF pressures measured, 4 were within the normal range. The mean +/- SEM total WBC count and total protein content of lumbar CSF were 533.4 +/- 256.5 cells/mu/microliter and 163.2 +/- 25 mg of protein/dl, respectively. As with cisternal CSF, the WBC differential count of lumbar CSF was predominantly lymphoplasmacytic cells. Of 5 lumbar CSF, 4 contained PMN cells, but the percentage was less than the PMN cell percentage of cisternal CSF. Although variable, the general pattern of CSF abnormality associated with granulomatous meningoencephalomyelitis was different from the CSF abnormalities commonly seen with viral, bacterial, or mycotic encephalitides. 相似文献
970.
Characteristics of Salmonella isolated from animals at a veterinary medical teaching hospital 总被引:3,自引:0,他引:3
J S Ikeda D C Hirsh S S Jang E L Biberstein 《American journal of veterinary research》1986,47(2):232-235
Salmonella belonging to 47 serotypes was isolated from animals at the University of California Veterinary Medical Teaching Hospital during the years 1974 to 1983. Salmonella belonging to 12 serotypes accounted for 89% of the 725 isolates. Salmonella typhimurium (including var copenhagen) was the most commonly isolated serotype, but during 1981 to 1983, S krefeld and S saint-paul were predominant. Certain serotypes seemed to be isolated more frequently from extraintestinal sources (S typhi-suis, S dublin). Although resistance to ampicillin, kanamycin, neomycin, streptomycin, and sulfonamides was common (greater than 60% of the isolates were resistant), resistance to chloramphenicol, gentamicin, and trimethoprim-sulfonamides was infrequent, except for isolates of S krefeld and S saint-paul. 相似文献