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941.
Cockram MS Kent JE Goddard PJ Waran NK Jackson RE Mcgilp IM Southall EL Amory JR Mcconnell TI O'Riordan T Wilkins BS 《Veterinary journal (London, England : 1997)》2000,159(2):139-146
The effect of a novel lairage environment on the ability of sheep to recover from 16 h of transport was investigated. Sheep were transported from grass paddocks to either novel outside paddocks or inside pens, and housed groups were transported to either familiar or novel inside pens. During transport, sheep from outside paddocks lay down less than those from inside pens. In sheep transported to inside pens, those from outside paddocks spent more time lying and spent less time eating; hay and water intakes during the first 12 h post-transport were lower than those previously kept inside. There was no obvious effect of a novel environment post-transport on blood biochemistry, suggesting that the lower post-transport feed and water intakes in a novel environment did not have a significant effect on the ability of the sheep to recover from the feed and water deprivation associated with transport. 相似文献
942.
J.R. Paul-Murphy DVM P.D. Koblik DVM MS G. Stein DVM D.G. Penninck DVM 《Veterinary radiology & ultrasound》1990,31(4):218-224
The psittacine skull is a complex anatomic structure, frequently traumatized but difficult to adequately image with standard radiographic procedures. Multiple views including a ventrodorsal, a lateral, and complementary oblique projections are necessary to fully evaluate potential skull fractures in the avian patient. Magnification radiography is a relatively easy procedure that aids the review of small osseous structures. Familiarity with psittacine skull anatomy greatly facilitates radiographic interpretation of cranial trauma. 相似文献
943.
Lakritz J Tyler JW Hostetler DE Marsh AE Weaver DM Holle JM Steevens BJ Denbigh JL 《American journal of veterinary research》2000,61(9):1021-1025
OBJECTIVE: To determine the effects of pasteurization of colostrum on serum lactoferrin concentration and neutrophil oxidative function by comparing values from calves given pasteurized (76 C, 15 minutes) colostrum versus calves given fresh frozen colostrum. ANIMALS: 8 Holstein bull calves were used to study the effects of pasteurization of colostrum on the absorption of lactoferrin and neutrophil oxidative burst. Three additional calves were used to study the effect of exogenous lactoferrin on neutrophil oxidative burst. METHODS: Calves were fed fresh frozen or heat pasteurized colostrum (76 C for 15 minutes) via esophageal feeder within 4 hours of birth. Neutrophils were isolated from whole blood samples. Neutrophil oxidative burst was induced by phorbol ester (300 ng/ml) stimulation of cells (1 X 10(6) cells) at 37 C. Serum lactoferrin concentrations were compared, using immunoblot analysis. Serum IgG concentrations were determined by radial immunoassay. Comparisons were made between the use of the 2 types of colostrum in calves by measuring subsequent serum IgG and lactoferrin concentrations and neutrophil superoxide production. RESULTS: Serum IgG and lactoferrin concentrations increased more in calves receiving fresh frozen colostrum. Neutrophil superoxide production was higher in neutrophils prepared from calves receiving fresh frozen colostrum. Colostral lactoferrin addition to neutrophil incubations resulted in increased oxidative burst. CONCLUSIONS AND CLINICAL RELEVANCE: Compared with calves given fresh frozen colostrum, calves given pasteurized colostrum had decreased serum IgG and lactoferrin concentrations and neutrophil superoxide production 24 hours after administration. These results suggest that pasteurizing bovine colostrum at 76 C for 15 minutes has substantial effects on passive transfer of proteins and neutrophil function. 相似文献
944.
A longitudinal study was carried out to determine the prevalence, distribution and intensity of gastrointestinal (GI) nematodes in traditional, small-scale dairy and large-scale dairy cattle farms in Iringa district, Southern highlands of Tanzania. Coprological examination of cohorts for GI nematode eggs in faeces, tracer worm counts and pasture larval counts were performed monthly for 1 year. Results indicated that the type of management, especially the grazing habit has a significant influence on the prevalence and intensity of GI nematodes. The predominant nematodes were Cooperia spp. (51.6%), Oesophagostomum radiatum (35.7%) and Haemonchus placei (10.2%). The worm burden in tracers was mainly composed of Cooperia spp. (83%) in large-scale dairy farms, while O. radiatum was dominant (60.8%) in traditional farms. Faecal egg counts (FEC) and tracer worm counts were generally low and FEC peaked only in calves and weaners/yearlings. Adults and all age groups in small-scale dairy farms had very low FEC throughout the year. Pasture larval counts, FEC and tracer worm counts peaked towards the end of the rainy season. Based on conditions of the study area, farmers could save substantial amount of money through strategic treatments as opposed to the previous routine of treating the whole herd at least four times a year. Strategic treatments are recommended in calves and weaners only in traditional and large-scale dairy farms. Strategic treatment of adults and small-scale dairy cattle might be not necessary. Strategic treatments at the end of the rainy/early dry season (May/June) and at the end of the dry/early rainy season (November/December) are recommended in the district. An additional treatment against GI nematodes in calves during the mid rainy season (February/March) might be important. 相似文献
945.
C. G. Bookhout R. J. Monroe R. B. Forward Jr. J. D. Costlow Jr. 《Water, air, and soil pollution》1984,21(1-4):199-216
Survival of Rhithropanopeus harrisii larvae from hatching to first crab stage occurred in Na2CrO4 concentrations from 1.1 to 29.1 ppm. Estimated LC50 for complete zoeal development was 17.8 ppm Na2CrO4 and it was 13.7 ppm for development to first crab stage. A concentration of 1.1 ppm Na2CrO4 was nontoxic, while Na2CrO4 concentrations of 7.2 and 14.5 ppm were sublethal and concentrations of 29.1 to 58.1 ppm were acutely toxic. Low concentrations of Na2Cr04 caused an increase in swimming speed and high concentrations caused a decline. Survival of Callinectes sapidus larvae occurred in Na2CrO4 concentrations from 1.1 to 4.7 ppm. The LC50 for complete zoeal development was estimated to be 2.9 ppm Na2CrO4 and the LC50 for development to first crab stage was estimated to be 1.0 ppm Na2CrO4 The total Cr in sodium chromate is 32% by weight (Tacey,1981), hence, the total Cr concentrations tested were 32% of the Cr salts given above. Statistical analyses of the data on survival, duration and mortality of larvae are presented. 相似文献
946.
The possible influences of contaminant bacteria, Pseudomonas fluorescens, infectious pancreatic necrosis virus (IPNV) and environmental stress on the development of vaccine-related peritoneal adhesions in Atlantic salmon, Salmo salar L., pre-smolts were investigated. Groups of 50 fish (≈ 30 g) vaccinated with a commercial, triple valent, metabolizable oil-adjuvanted vaccine were pre-injected with IPNV, co-injected with Pseudomonas fluorescens or subjected to routine stress both solely and in combination. Fish from each group were sampled monthly over 3 months. Vaccine side-effects were scored macroscopically and examined histologically. Fibrous adhesions were apparent in all groups from the first sampling date. Treatments including co-injection of P. fluorescens and additional environmental stress were found to confer significantly higher degrees of adhesion than vaccine alone. The findings are discussed in relation to vaccination procedures. Persistent or covert IPNV infection could not be confirmed in subsequent samplings. 相似文献
947.
Castration is an ancient husbandry procedure used to produce docile cattle for draught work, to reduce unwanted breeding, and to modify carcass quality. All the physical methods used to castrate cattle have side-effects and cause pain. The plasma cortisol response to castration using Burdizzo clamps and, by inference, the acute pain experienced, is less than that caused by surgical, rubber-ring or latex-band castration. The cortisol response may be influenced by the age of the animal castrated, but this has not been well defined. Local anaesthesia virtually eliminates the cortisol response, and thus the acute pain, caused by rubber-ring or latex-band castration, but needs to be combined with a systemic analgesic such as the non-steroidal anti-inflammatory drug ketoprofen to eliminate the cortisol response to Burdizzo or surgical castration. When used alone, ketoprofen sometimes reduces the cortisol response to Burdizzo or surgical castration but may need to be accompanied by local anaesthesia to eliminate the pain-induced behaviour seen during the castration process itself. Thus, pharmacological methods are available to virtually eliminate the acute pain experienced by calves during the 12 h following castration. The use of these methods is an additional cost for farmers and may be limited by the availability of drugs for farmers to use and the scarcity of veterinarians in farm animal practice. 相似文献
948.
The poultry red mite Dermanyssus gallinae is a major pest and widespread ectoparasite of laying hens and other domestic and wild birds. Under optimal conditions, D. gallinae can complete its lifecycle in less than 10 days, leading to rapid proliferation of populations in poultry systems. This paper focuses on developing a theoretical model framework to describe the population dynamics of D. gallinae. This model is then used to test the efficacy and residual effect of different control options for managing D. gallinae. As well as allowing comparison between treatment options, the model also allows comparison of treatment efficacies to different D. gallinae life stages. Three different means for controlling D. gallinae populations were subjected to the model using computer simulations: mechanical cleaning (killing once at a given time all accessible population stages), sanitary clearance (starving the mite population for a given duration, e.g. between flocks) and acaricide treatment (killing a proportion of nymphs and adults during the persistence of the treatment). Simulations showed that mechanical cleaning and sanitary clearance alone could not eradicate the model D. gallinae population, although these methods did delay population establishment. In contrast, the complete eradication of the model D. gallinae population was achieved by several successive acaricide treatments in close succession, even when a relatively low treatment level was used. 相似文献
949.
Tears to the lateral glenohumeral ligament appear to be uncommon in dogs. Two Labrador Retrievers were arthroscopically diagnosed with lateral glenohumeral ligament tears of the shoulder. Both cases failed to respond to conservative management. Surgical stabilisation of the lateral aspect of the shoulder joint was achieved using an arthroscopically placed suture using a hanging limb technique. Lameness resolved in both cases. 相似文献
950.
The clinicopathologic, light, and scanning electron microscopic features of eperythrozoonosis in four naturally infected llamas 总被引:2,自引:0,他引:2
W J Reagan F Garry M A Thrall S Colgan J Hutchison M G Weiser 《Veterinary pathology》1990,27(6):426-431
The hematologic, biochemical, and light and scanning electron microscopic features of eperythrozoonosis in four llamas are described. One female and three male yearling llamas were presented for evaluation of chronic weight loss. Three of four llamas had historical evidence of chronic inflammatory conditions. On examination, multiple clinical problems were apparent, including poorly to non-regenerative anemia, inflammatory disease, and hypoproteinemia. Coccoid- and ring-shaped basophilic organisms were present on the erythrocytes of all the llamas. On scanning electron microscopy, individual, pairs, and clusters of coccoid-shaped organisms were present on the erythrocytes. The organisms measured 0.4 to 0.6 micron in diameter and caused no marked deformation of the erythrocyte membrane. A rare organism could be found that produced a slight indentation into the erythrocyte membrane. The light and scanning electron microscopic morphologic features suggested that the organism was an Eperythrozoon. Serial evaluation of serum iron concentrations of the llamas showed a decrease serum iron in all animals, with a concurrent decrease in the total iron binding capacity and percent transferrin saturation in two of the llamas. Common abnormalities seen on serum electrophoresis included a decrease in albumin and beta serum fraction in all llamas and a decrease in the gamma globulin fraction of two individuals. 相似文献