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991.
M Steinhardt S Reimer J Kutschke U Bünger 《Archiv fuer experimentelle veterinaermedizin》1989,43(1):111-119
4 female and 2 male untrained fattening pigs, weighing 43.9 +/- 1.6 kg at the beginning of the experiment underwent continuous measurement of VO2, VCO2, and rectal temperature, prior to, during, and after running on a horizontal exercise belt set to speeds of 0.7, 1.3, and 2.5 m.s-1. The highest values of VO2 and VCO2 (ml-min-1/kg-1) and rectal temperature (degrees C) were usually measured few minutes after running. They were 18.84 +/- 3.65 and 20.4 +/- 4.53 as well as 41.2 +/- 0.4, 28.41 +/- 4.07 and 33.26 +/- 5.92 or 41.3 +/- 0.5, 26.21 +/- 7.7 and 32.32 +/- 7.14 as well as 40.5 +/- 0.7, depending on the above belt speeds. Exercise belt speeds of 1.3 to 1.8 m.s-1 were found to be suitable for testing aerobic metabolic capacity of untrained young pigs. 相似文献
992.
The ultrastructure of sarcocysts of macro- and microscopic species of Sarcocystis was compared from naturally infected water buffalo from India. Grossly visible sarcocysts had walls consisting of cauliflower-like villar protrusions, typical of S. fusiformis. The sarcocyst wall of the microscopic species of Sarcocystis was 6.4 microns thick and consisted of tightly packed conical villar protrusions that were 9.6 microns long and 3.7 microns wide at the base. At approximately 3 microns above the base, the distal two-thirds of the villar protrusion became conical shaped and was bent laterally at an angle of 45 degrees to the sarcocyst surface. The granular layer beneath the villar protrusions was 0.9 microns thick. In S. levinei the granular layer was 1.9 microns thick, the villar protrusions were narrow and it had a highly undulating primary cyst wall. Whether the microscopic S. levinei-like sarcocysts of Indian and Malaysian water buffalo are distinct species of Sarcocystis will require further investigation. 相似文献
993.
Isolation, characterization and in vitro mitogenic stimulation of peripheral blood lymphocytes from an American buffalo.
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A rapid and reproducible method is described for the isolation and characterization of leukocytes from the peripheral blood of an American buffalo (bison). Centrifugation of the buffy coat cells on a Percoll gradient (1.079 g/mL) at 650 x g for 20 min resulted in the separation and high yields of pure viable leukocytes. The sheep erythrocyte-rosetting technique (ER) showed that 59% of the cells were ER+ (T lymphocytes). Fluorescein isothiocyanate (FITC)-conjugated peanut agglutinin and FITC-conjugated concanavalin A revealed 77% and 89% positive cells, respectively. The isolated leukocytes contained adherent accessory cells and functionally active T and B lymphocytes which proliferated in response to both T and B cell mitogens and to exogenous recombinant bovine interleukin-2 in the absence and/or presence of the thiol compound 2-mercaptoethanol. 相似文献
994.
虽然双层经营体制已经得到确立,但至今其经营客体或对象在实践中仍然是不清楚的,而且就统分结合两方面来看,统的职能也严重不足,致使家庭经营的弊端依然存在,双层经营的功能难以充分发挥.为此.笔者提出,“两田制”是完善双层经营体制的有效形式。它有利于实现农业的适度规模经营,可大幅度地提高农业劳动生产率和农产品商品率,还形成了农村劳动力合理流动的机制,有利于农村经济的全面发展和农业机械化的推广。所以,笔者主张,“两田制”应谈有计划地加以推广. 相似文献
995.
Effect of pelleting and beta-glucanase supplementation on the ileal and fecal digestibility of a barley-based diet in the pig 总被引:5,自引:0,他引:5
The influences of pelleting and beta-glucanase supplementation on the digestibility of dietary components in a barley-based diet were investigated in pigs fitted with cannulas in the terminal ileum. The diet contained 49.0% starch, 18.9% crude protein and 14.8% dietary fiber, with arabinoxylans (4.9%), mixed-linked beta-glucans (3.4%) and cellulose (3.3%) as the main fiber components. Pelleting increased mixed-linked beta-glucan solubility from 45 to 62%. Neither treatment influenced the ileal or fecal apparent digestibilities of dry matter (64 and 80%, respectively), energy (62 and 79%), crude protein (53 and 75%), crude fat (26 and 27%) or dietary fiber (58 and 72%). However, pelleting increased (P less than .01) the pre-ileal apparent digestibility of starch from 91.5 to 95.3% and decreased (P less than .03) that of ash from -10 to -23%, while increasing (P less than .005) the fecal apparent digestibility of starch from 98.6 to 99.7%. The solubility of mixed-linked beta-glucans in ileal digesta was lower (P less than .001) in pelleted (26%) than in unpelleted (58%) diets. beta-glucanase supplementation also increased (P less than .05) the ileal apparent digestibility of starch, from 92.6 to 94.3%, and of mixed-linked beta-glucans, from 95.7 to 97.1%. Significant between-pig differences in the apparent digestibility of dietary components were observed. In conclusion, treatments that disrupt the endosperm cell walls in barley can increase the proportion of the diet digested prior to the large intestine. 相似文献
996.
In 1985 and 1986, large-scale natural die-offs of sandhill cranes in Texas were attributed to fusariomycotoxicosis. These birds demonstrated a progressive loss of motor control to the neck, wings, and legs. Based on necropsy and/or histopathology of 31 cranes, the most common lesions involved skeletal muscle and included hemorrhages, granulomatous myositis, thrombosis, and vascular degeneration. Serum chemistry results revealed that levels of creatinine kinase, aspartate aminotransferase, and alanine aminotransferase were above published normals. However, only alanine aminotransferase was higher in clinically affected cranes than in normal cranes collected from the same area. 相似文献
997.
Calcium fluxes were measured, in vivo, in both directions across the ovine reticulorumen wall of four sheep when the luminal potassium concentration was either 30 mmol litre-1 or 90 mmol litre-1. Neither fluxes were affected by an increased potassium concentration although net magnesium absorption was decreased (PO less than 0.05) and the transmural potential difference was increased (P less than 0.01) under these conditions. The results obtained suggest that, unlike magnesium, calcium is transported bidirectionally across ovine ruminal tissue independently of the transmural potential difference across the rumen wall. 相似文献
998.
999.
1000.
Llama reproduction 总被引:1,自引:0,他引:1
L W Johnson 《Veterinary Clinics of North America: Food Animal Practice》1989,5(1):159-182
The reproductive anatomy, physiology, and breeding behavior of the llama is unique enough to make familiarity with it imperative. Female puberty averages 12 months, while many males are not reproductively functional until after 3 years. Proper management of a breeding pair or herd is necessary to maintain maximum reproductive performance. Proof of pregnancy is suggested by rejection of the male and may/should be confirmed by progesterone assay, rectal palpation, or ultrasound techniques. The postpartum female is notable for breeding back rapidly, with high pregnancy rates resulting. Both male and female factors enter into llama infertility, with each gender having significant incidence of reproductive anatomical abnormalities. Management as well as acquired infertility problems (heat factors, trauma, infection, neoplasia, and hormonal imbalances) contribute to the bulk of infertility cases investigated. Techniques used to diagnose infertility in llamas are quite comparable to the equine species; however, female body size and semen analysis in the male present significant challenges. The approach to therapy has been quite empirical to date, owing to lack of consistent problems and numbers to afford conclusive trials. Alterations of pregnancy include resorption, abortions, and stillbirths. Resorption between 30 to 60 days of gestation is reported regularly. Abortions caused by stress occur regularly. Infection abortions caused by leptospirosis, toxoplasmosis, and chlamydiosis are to be expected. Ponderosa pine-related abortions are suspected. In summary, I find use for a broad background in large animal theriogenology to apply to llama infertility. There no doubt are additional diagnostic techniques and therapeutic regimens that have application, and it is up to us all to keep good records and share the information. 相似文献