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991.
992.
A retrospective study of 3456 deliveries was conducted from the records of four Standardbred broodmare farms where mares were bred by artificial insemination and maintained under close veterinary supervision. Retained fetal membranes (RFM) were observed in 10.6% of the deliveries. Retained fetal membranes occurred more frequently (p < 0.05) after dystocia and in mares which had RFM the previous year. Retained fetal membranes after normal foaling had no significant effect on the reproductive performance (pregnancy rate, pregnancy loss rate, or foaling rate), nor on the general health of the mares, regardless of the duration of RFM (3 to 144 hours). Postfoaling laminitis was not observed. Oxytocin therapy of mares with RFM starting at two hours postpartum significantly reduced the incidence of RFM ≥ 8 hours. Mares with RFM which had received intrauterine antimicrobials between foaling and first breeding had a foaling rate similar to mares with RFM which had not received intrauterine therapy.  相似文献   
993.
994.
995.
Sheep affected by broken mouth periodontal disease (P.D.) were examined over a twelve month period for different clinical parameters. It is suggested that P.D. in sheep is an episodic phenomenon similar to human P.D., and that only a few animals with signs of P.D. may undergo clinically significant destruction over a yearly period. No single parameter could reliably predict future deterioration in other parameters.  相似文献   
996.
1. Observations were made on the use of food pans and food trays by commercially grown broiler chickens.

2. Birds fed by going inside the feeders on top of the food or from standing around the outside of the feeders. The feeding times of birds inside feeders were significantly longer than those of birds outside. Different reasons to account for this are proposed for the 2 types of feeder.

3. The total number of birds able to feed together from a tray or pan changed as the birds grew. With trays this change in the number of birds was a steady decline. With pans the change was non‐linear and reflected a changing ratio of birds eating in to birds eating out. This ratio was influenced by pan design features and by competition for feeding space.

4. The data suggest that a linear measure of feeding space, as used in research trials and Codes of Practice for Welfare, does not adequately describe birds’ access to and use of feeding space. Implications for both research and the commercial industry are discussed.  相似文献   

997.
给8头生后3d的哺乳仔猪经口感染猪流行性腹泻病毒(PEDV)“吉”毒株,于感染后18、30、45和96h各扑杀2头,以透射电镜和扫描电镜观察了小肠粘膜上皮细胞及肠系膜淋巴结的超微结构。结果表明,小肠上皮细胞的病变因感染时间不同而有明显差异。上皮细胞的脱落和残留上皮细胞超微结构的破坏,以感染后30h最严重,病毒在这些上皮细胞内的增殖最显著。感染后45h,见有大量新生上皮细胞修补损伤的肠绒毛。感染后96h,小肠绒毛短缩、粗大乃至发生融合。实验仔猪肠系膜淋巴结内巨噬细胞和淋巴细胞的超微结构均遭到破坏,在巨噬细胞内见有PED冠状病毒粒子。  相似文献   
998.
Equine polymorphonuclear (PMN) and mononuclear (MN) leucocytes were separated on Percoll gradients and used to study the chemoattractant properties of the polar ether-linked phospholipid, platelet activating factor (PAF). Six concentrations of PAF ranging from 1 ng/ml to 100 g/ml were studied in each of two in vitro assay systems, the agarose microdroplet and a microfilter technique. Very significant (p<0.01) increases in the movement of both PMN and MN cells were obtained with most concentrations of PAF. In two instances there was no apparent concentration-response relationship, although the action of PAF was approximately bell-shaped in two others. The possible significance of these findings for equine inflammatory conditions is discussed.  相似文献   
999.
In conscious pigs the influence of intravenous infusion of live E. coli (7×108/kg), of the equivalent amount of endotoxin (20 g/kg) or of a high dose of endotoxin (2.5 mg/kg) on the hemodynamic, clinical and pathological parameters and on survival rate was studied. E. coli and endotoxin infusion resulted in pulmonary hypertension, systemic arterial hypotension, a decrease in cardiac output and an increase in heart rate. Clinical signs were characterized by respiratory and nervous disturbances, whereas necropsy revealed hemorrhages and edema in several organs. Although these findings were similar in the three groups, a marked difference in lethality was observed. Infusion of E. coli or of the high dose of endotoxin resulted in a significant mortality, whereas all pigs survived the infusion of the low dose of endotoxin. This suggests that the lethal pathophysiological mechanisms may only become activated when a sufficient amount of endotoxin is released into the circulation.  相似文献   
1000.
A survey of the histology of gastric biopsies in 501 dogs, consisting of 19 clinically healthy dogs and 482 vomiting dogs is presented. Whole stomachs of four young clinically healthy laboratory dogs were used as controls. Eleven percent of forceps biopsies were unsuitable for examination; all suction biopsies were of good quality. Slight to severe gastritis was found in 168 vomiting dogs (35%), whereas five dogs (26%) of the clinically healthy group showed a mainly slight gastritis. Superficial and diffuse gastritis were the most prominent findings in the 168 dogs with gastritis. A single type of gastritis was found in 114 dogs, a combination of different types in 54 dogs. Gastric atrophy was seen in 23 (5%) vomiting dogs and in three (15%) clinically healthy dogs, atrophy with a slight to severe fibrosis in 21 (4%) vomiting dogs, and in 84 (17%) vomiting dogs and two (11%) healthy dogs, gastric fibrosis was present. Carcinomas were seen in 26 vomiting dogs, of which 17 also had gastritis. A differential diagnosis of granulomatous gastritis/carcinoma had to be made in one case. Seven dogs showed a lymphosarcoma, and in six other dogs a differential diagnosis of lymphosarcoma and/or gastritis was made. One adenomatous polyp was seen. In one clinically healthy dog an adenomyoma was diagnosed. Ulceration was found in 24 dogs, but only five of these lacked other lesions. Other biopsy findings were pseudopyloric metaplasia, hyperplasia, cysts, calcification and edema. Some dogs showed "antralization".  相似文献   
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