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961.
1. Male broiler chickens were killed at various times up to 36 h after withdrawal of food; hepatic and muscle glycogen concentrations and pH were compared with those of control birds given continuous access to food and water. 2. Liver glycogen was reduced to negligible concentrations (less than 1 mg/g) within 6 h of food deprivation and the initial pH was elevated. 3. Withdrawal of food had no effect on glycogen concentrations in the m. pectoralis superficialis (PS) but reduced them in the m. biceps femoris (BF); the reduction was significant after 12 h. Ultimate pH was elevated by fasting in the BF, but not the PS. 相似文献
962.
S L Ihle R W Nelson J R Cook 《Journal of the American Veterinary Medical Association》1988,192(1):71-72
Hypercalcemia caused by primary hyperparathyroidism was believed to be responsible for seizures in a dog. A diagnostic evaluation showed no primary causes of seizures. After surgical excision of the adenomatous parathyroid gland, phenobarbital treatment was discontinued, without recurrence of seizures. 相似文献
963.
The vascular morphology of the proximal femur, tibiotarsus and tarsometatarsus was studied in growing broiler chicks. A carousel was used to exercise one group of 24 birds for four periods of 15 minutes each day. A second group (controls) were not exercised. Some birds were killed during the course of the experiment, and the remainder after 25 days of exercise when they were 33 days old. After killing the limbs were perfused and the bone extremities cleared. The bone extremities were then cut into 1 mm thick slabs and examined. There were abnormalities of the physis and physeal vasculature in 18 (25 per cent) of the bone extremities from the exercised birds and in 24 (40 per cent) of the bone extremities from the unexercised (control) birds. The low level of activity in the unexercised fowls of the present study appeared to contribute to these abnormalities. 相似文献
964.
F J Derksen N E Robinson J S Scott J A Stick 《American journal of veterinary research》1988,49(6):933-938
Ponies with recurrent airway obstruction (principal ponies) and their controls were given aerosolized Micropolyspora faeni antigen via endotracheal tube during a period when the principal ponies were in disease remission. In both groups of ponies, we performed bronchoalveolar lavage (BAL) and measured pulmonary function at base line, and 5 hours after aerosol administration of 30 ml of 0.9% NaCl solution or 30 ml of 1% w/v particulate M faeni antigen in 0.9% NaCl solution. In both groups of ponies, aerosolized M faeni antigen increased WBC count, neutrophil numbers, and albumin concentration in BAL fluid, but macrophage numbers decreased. In the principal ponies, BAL mast cell numbers were decreased 5 hours after administration of M faeni antigen. The M faeni antigen had no effect on the mechanical properties of the lungs or on gas exchange in the control ponies, but did increase respiratory frequency minute ventilation and pulmonary resistance, and decreased arterial oxygen tension in the principal ponies. Changes in pulmonary function were apparent only in the principal ponies, which suggests that neutrophils, per se, do not cause pulmonary dysfunction and that M faeni may be one of the etiologic agents involved in chronic obstructive pulmonary disease. 相似文献
965.
966.
Four asexual generations of Eimeria mitis were identified. The first three developed above the epithelial cell nuclei, but the fourth developed above and below. Meronts measured 13.8 x 16.4 microns, 16.1 x 16.4 microns, 12.1 x 14.6 microns, and 9.5 x 12.4 microns, respectively, of generations 1, 2, 3, and 4. They matured at 36, 67, 72, and 88 hr postinoculation (PI) and contain 20-24, 16-20, 10-14, and 7-10 merozoites, respectively. Merozonts measured 7.2 x 1.9 microns, 8.5 x 2.5 microns, 9.6 x 2.0 microns, and 6.75 x 2.75 microns, respectively. The first two types of meronts were deep in the crypts and epithelial cells. The third and fourth types of meronts were along the side and tip of the villi. Gametocytes developed from third and fourth generation. Gamonts were usually below the nuclei of the epithelial cells. Parasitism was primarily in the ileum, ceca, and rectum and also in the yolk-sac diverticulum. 相似文献
967.
Immune exclusion of Haemonchus contortus larvae in sheep: dose dependency, steroid sensitivity and persistence of the response 总被引:2,自引:0,他引:2
F Jackson H R Miller G F Newlands S E Wright L A Hay 《Research in veterinary science》1988,44(3):320-323
Naive and immune sheep, treated with anthelmintic, challenged directly into the abomasum and killed 48 hours later were used to examine the steroid sensitivity, persistence and dose dependency of immune mechanisms which result in the failure of incoming Haemonchus contortus larvae to establish (immune exclusion). Immune exclusion was almost totally abolished by corticosteroid treatment, the mean percentage of larvae establishing in the mucosa of immune sheep was 1.4 per cent of the challenge infection whereas in those treated with dexamethasone it was 24.4 per cent and in naive sheep 27.3 per cent. Immune animals challenged after seven and 42 days without antigenic experience excluded more than 90 per cent of the challenge larvae from their mucosae, whereas those challenged after 84 days without antigenic experience were as susceptible as naive animals. Immune exclusion was dose dependent, animals challenged with 10(6) and 10(5) larvae excluded 93 per cent and 82.5 per cent of the challenge dose whereas those challenged with 10(4) larvae failed to exclude larvae. 相似文献
968.
D. W. MACY 《The Journal of small animal practice》1988,29(9):597-602
A cutaneous mast cell tumour associated with Darier's sign in a cat with multiple neoplasms is described. A 14-year-old cat with multiple neoplasms, one of which was a mast cell tumour developed marked subcutaneous oedema and erythema following palpation. The phenomenon is similar to Darier's sign described in people with mast cell tumours. The pathology of the Darier's sign is discussed. 相似文献
969.
970.
Twenty-five strains of Escherichia coli isolated from turkeys were characterized for their serum resistance and virulence. An in vitro bactericidal assay was used to determine the serum resistance of E coli. Virulence was determined by survival time after IV inoculation of each strain into 3-week-old turkeys. Serum-resistant E coli strains were generally found to be virulent for turkeys, whereas serum-sensitive E coli strains were avirulent. Of the 25 strains, 18 strains were placed in the 2 categories of serum-resistant/virulent and serum-sensitive/avirulent. Five strains were serum-resistant and avirulent, and 2 strains were serum-sensitive and virulent. Serum resistance appears to be an important determinant of virulence for E coli in turkeys; however, the requirement for other virulence factors, in addition to serum resistance, was suggested by the finding that 5 serum-resistant strains were avirulent in turkeys. 相似文献