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31.
Angus bulls (n = 16) selected for either high- or low-milk EPD but similar growth EPD were mated within location at random to Angus cows. Daughters were bred to calve at 2 yr of age and annually until 6 yr of age. Milk yield was measured four times during lactation with a portable milking machine to estimate 12-h milk yield. Milk was collected for analysis of the percentage of fat and protein. A mixed model procedure was used to analyze the weaning weight, milk yield, and milk component data. The model for weaning weight included location, genetic line of sire, gender of calf, and age of dam. Calf age at weaning was used as a covariate. The model for the milk yield and components included location, genetic line of sire, gender of calf, period, and age of dam. Random effects for all models included sire of dam nested within line, sire of calf, and year. Genetic line was a significant source of variation for milk yield (P < 0.01) and weaning weight (P < 0.01) but not for percentage of fat or protein. Location was significant for milk yield (P < 0.01), fat (P < 0.01), protein (P < 0.01), and weaning weight (P < 0.01). The interaction of line with location was not significant except for percentage of protein (P < 0.01). Age of dam was significant for milk yield (P < 0.01), weaning weight (P < 0.01), and percentage of protein (P < 0.01), but not for percentage of fat (P = 0.29). Line difference for mean weaning weight was 18.1 kg, which is similar to the difference between lines for milk EPD (19 kg). Weaning weights from high-milk EPD line daughters were heavier (P < 0.01) than low-milk EPD line daughters at each age of dam evaluated. Cows nursed by males had higher milk yields (4.33 kg/12 h) than cows nursed by heifers (4.0 kg/12 h). The difference in yields for gender was significant for 2-, 3-, and 5-yr-old cows, but not for 4- (P < 0.052) and 6-yr old (P < 0.15) cows. Correlation coefficients between weaning weight and weaning EPD, milk EPD, and total maternal EPD were greater than zero (P < 0.01) (0.76, 0.65, and 0.89, respectively). Daughters of sires with high-milk EPD produced more milk at each age and weaned heavier calves than daughters of sires with low-milk EPD. These results confirm the value of milk EPD for improvement of weaning weights in beef cattle and also validate age of dam effects on milk yield and the associated effects on weaning weights. 相似文献
32.
Richter RA Freeman DE Wallig M Whittem T Baker GJ 《American journal of veterinary research》2002,63(7):934-941
OBJECTIVES: To study the functional and structural responses of the right dorsal colon (RDC) of ponies to phenylbutazone (PBZ) in vitro at a concentration that could be achieved in vivo. ANIMALS: 8 adult ponies. PROCEDURE: Short circuit current and conductance were measured in mucosa from the RDC. Tissues incubated with and without HCO3- were exposed to PBZ, bumetanide, or indomethacin. Bidirectional Cl- fluxes were determined. After a baseline flux period, prostaglandin E2 (PGE2) was added to the serosal surfaces and a second flux period followed. Light and transmission electron microscopy were performed. RESULTS: Baseline short circuit current was diminished significantly by PBZ and indomethacin, and increased significantly after addictions of PGE2. After PGE2 was added, Cl- secretion increased significantly in tissues in HCO3- -free solutions and solutions with anti-inflammatory drugs, compared with corresponding baseline measurements and with control tissues exposed to PGE2. Bumetanide did not affect baseline short circuit current and Cl- fluxes. The predominant histologic change was apoptosis of surface epithelial cells treated with PBZ and to a lesser extent in those treated with indomethacin. CONCLUSIONS AND CLINICAL RELEVANCE: Prostaglandin-induced Cl- secretion appeared to involve a transporter that might also secrete HCO3-. Both PBZ and indomethacin altered ion transport in RDC and caused apoptosis; PBZ can damage mucosa through a mechanism that could be important in vivo. The clinically harmful effect of PBZ on equine RDC in vivo could be mediated through its effects on Cl- and HCO3- secretion. 相似文献
33.
de Veau IF Pedersoli W Cullison R Baker J 《Journal of veterinary pharmacology and therapeutics》2002,25(3):195-200
Phenylbutazone was administered intravenously to a group of 11 beef steers at a dosage of 6 mg/kg of body weight. Whole plasma and protein-free plasma were analyzed for phenylbutazone residues. Pharmacokinetic parameters of total and free phenylbutazone in plasma were calculated using a noncompartmental method. In regards to whole plasma data, the mean volume of distribution at steady state (Vss), was 140 mL/kg body weight, with a mean (+/-SEM) terminal elimination half-life (t1/2) of 34 +/- 9 h. The mean clearance was 3.2 mL/h/kg body weight. The Vss, as determined from the protein-free plasma fraction, was 54093 mL/kg body weight. This larger Vss of free phenylbutazone compared with total plasma phenylbutazone was attributed to a high degree of plasma protein binding, as well as the greater penetration of free phenylbutazone into tissues. The mean t1/2 of free phenylbutazone was 35 +/- 12 h. This similarity to the t1/2 estimated from total plasma phenylbutazone data is attributed to an equilibrium between free and plasma phenylbutazone during the terminal elimination phase. The pharmacokinetic parameters of free and total plasma phenylbutazone in beef steers are statistically similar to those previously reported for lactating dairy cows. 相似文献
34.
Gaynor JS Brevard S Mallinckrodt C Baker G Wander K 《Veterinary therapeutics : research in applied veterinary medicine》2002,3(4):425-434
A randomized, placebo-controlled, parallel study was conducted to investigate the effectiveness of oral carprofen for the control of postoperative pain in dogs undergoing knee surgery for stabilization of ruptured cranial cruciate ligaments. Dogs were randomly assigned to treatment with carprofen (n = 10) or placebo (n = 9). Pain was assessed at 1, 2, 4, 6, 24, and 48 hours and 10 and 21 days postoperatively. Eight of 10 dogs treated with carprofen and five of nine dogs treated with placebo were given at least one dose of morphine as rescue therapy. The mean relative dose of morphine given at 1 hour (P =.01) and 24 hours (P =.02) after surgery was greater for dogs treated with carprofen than for dogs given a placebo. There were no significant postoperative differences in cortisol levels or any measured variable. It appears that the scoring system used was not sensitive enough to detect differences in pain between a known analgesic and a placebo. 相似文献
35.
36.
Magid JH Manohar M Goetz TE Baker GJ Ulbricht R Bontkowski S Ghantous S 《Journal of veterinary pharmacology and therapeutics》2000,23(2):81-89
Furosemide premedication of horses 4 h prior to exercise significantly attenuates exercise-induced pulmonary capillary hypertension which may help diminish the severity of exercise-induced pulmonary haemorrhage. As pulmonary hemodynamic effects of furosemide may be mediated via a reduction in plasma volume (which is most pronounced 15-30 min postfurosemide administration, with plasma volume recovering thereafter), we hypothesized that administration of furosemide at intervals shorter than 4 h before exertion may be more effective in attenuating the exercise-induced rise in pulmonary capillary blood pressure. Thus, our objective was to determine whether furosemide-induced attenuation of exercise-induced pulmonary arterial, capillary and venous hypertension would be enhanced when the drug is administered at intervals shorter than 4 h before exercise. Using established techniques, right atrial, and pulmonary arterial, capillary and wedge (venous) pressures were ascertained in seven healthy, sound, exercise-trained Thoroughbred horses in a randomized split-plot experimental design. Measurements were made at rest and during exercise performed at maximal heart rate (217 +/- 3 beats/min) in the control (no medications) experiments and following furosemide administration (250 mg intravenously (i.v.)) at 1, 2, 3 and 4 h before exercise. Sequence of treatments was randomized and 7 days were allowed between experiments on each horse. Although furosemide administration in the four treatment groups caused only insignificant changes in the pulmonary arterial, capillary and wedge pressures of standing horses, furosemide-induced reduction in mean right atrial pressure achieved statistical significance in the 2 h postfurosemide experiments. In the control studies, exercise was attended by statistically significant increments in mean right atrial, as well as pulmonary arterial, capillary and wedge pressures. Although exercise in each of the four furosemide experiments was also attended by significant increments in right atrial as well as pulmonary vascular pressures, in the 1, 2 and 3 h postfurosemide experiments, mean right atrial pressure increased to a significantly lower value than in the control study. Exercise-induced changes in pulmonary vascular pressures in the 1 h postfurosemide experiments were not different from the pressures in the control study. There was a significant attenuation of exercise-induced pulmonary capillary and venous hypertension in the 2, 3 and 4 h postfurosemide experiments, but significant differences among these treatments were not found. Thus, these data did not support the contention that administration of furosemide at intervals shorter than 4 h before exercise is more effective in attenuating exercise-induced pulmonary capillary or venous hypertension in Thoroughbred horses. 相似文献
37.
FJ Pena JA Gines J Duque V Vieitez R Martinez –Pérez L Madejón I Nuñez Martinez JM Moran S Fernández-García 《Reproduction in domestic animals》2006,41(2):189-190
A 6-year-old female Alaska Malamute dog was presented for evaluation of abdominal enlargement referred by a local veterinarian. On the history, the owner complained of chronic abdominal enlargement initiated more than 4 months ago, reduced appetite, occasional vomiting and general dullness. He also complained of greenish mucous intermittent vaginal discharge starting 10 days ago. The bitch was chronically treated with medroxiprogesterone acetate. A laparatomy was performed and fluid in the abdomen was found and aspirated during the surgery. Also a very fluid-filled distended uterus and a mass in the distal part of the left uterine horn were found. The mass was encapsulated by the omentum, but areas of necrosis and calcification were identified. Histopathological diagnosis was endometrial adenocarcinoma. 相似文献
38.
S Ikeda JM Prendes C Alonso-Montes A Rodríguez C Díez M Kitagawa H Imai E Gómez 《Reproduction in domestic animals》2006,41(5):383-385
In multiple ovulation and embryo transfer (MOET) programmes in cattle, a considerable number of morphologically poor-quality embryos continue to be produced; this is one of the limiting factors of the technique. Apoptosis has often been implicated in developmental arrest and fragmentation; these are regarded as poor traits of embryonic quality in mammalian pre-implantation embryos. In the present study, apoptosis was assessed in morphologically poor-quality embryos in comparison with good-quality embryos that were recovered from a MOET programme. Retarded embryos (two to 16 cell stage), morulae with severe fragmentation and morphologically good-quality morulae recovered from superstimulated cows at day 7 post-insemination were subjected to TdT-mediated dUTP nick-end labelling (TUNEL) and Hoechst staining. Cell nuclei that showed both TUNEL staining and apoptotic morphology were considered to be apoptotic. Apoptotic index (AI) was calculated as the percentage of apoptotic cells per embryo. Fifteen of 17 retarded embryos and 10 of 15 morphologically poor-quality morulae did not show signs of apoptosis. The mean AIs in the morphologically poor-quality embryos (two to 16 cell stage, 2.2%; poor morulae, 1.3%) were as low as that in the good-quality embryos (2.9%). These results suggest that another mode of developmental arrest and/or fragmentation that is independent of apoptosis occurs in morphologically poor-quality embryos recovered from MOET programmes. 相似文献
39.
40.
An analysis of records of plant pathogens first identified in Great Britain from 1970 to 2004 (inclusive) was undertaken to determine the numbers of new species that have become established over time. Results show that the numbers of newly recorded pathogens have not varied significantly. Of the 234 pathogens recorded for the first time between 1970 and 2004, 157 were fungi, 27 were oomycetes, 26 were viruses, 23 were bacteria, and one was a phytoplasma. Approximately 53% of pathogens were found on ornamental crops, 16% on horticultural crops, 15% on wild native species, 12% on agricultural crops, 2% on pasture plants and 2% on exotic forestry tree species. Where the origin of introductions was known or strongly suspected, 47% came from the Netherlands. About 38% of newly recorded pathogens with information on the location of first record were discovered in the South East region of England. Plant Pathologists regarded 19% of all new pathogens as important because of actual or potential economic/environmental losses. The results indicate that the numbers of new or important pathogens establishing in recent years are not increasing and that most new findings are associated with ornamental plants. 相似文献