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201.
Hygiene and sanitation play a major role in any effective disease control programme for poultry production and processing premises. Various deficiencies in disinfection may induce that chains of infections are not broken from one stock to another. The present study investigated the efficacy of disinfection on a broiler farm and in a plant processing poultry from the investigated farm. Besides inspection of disinfection, the influence of contamination on broiler carcasses and consequences of this contamination on sanitation of the processing lines were studied. Swabs from surfaces coming into contact with the handled raw material were taken and evaluated. The results obtained by a standard microbiological swab method were evaluated and compared with an ATP-bioluminescence method. The investigations included determination of total counts of microorganisms, coliform bacteria and moulds. When employing the standard plate-count method, the total counts of microorganisms (TCM) reached <1, 1-100 and >100 CFU in 0, 12 and 88% swabs on poultry farm and in 22%, 36% and 42% swabs in the processing plant, respectively. The bioluminescence method was used only in the processing plant and contamination corresponding to <100, 100-300 and >300 relative light units (RLU) was detected in 80%, 10% and 10% swabs respectively.  相似文献   
202.
A Bayesian procedure, which allows consideration of the individual variation in the feed resource allocation pattern, is described and implemented in 2 sire lines of rabbit (Caldes and R). The procedure is based on a hierarchical Bayesian scheme, where the first stage of the model consists of a multiple regression model of feed intake on metabolic BW and BW gain. In a second stage, an animal model was assumed including batch, parity order, litter size, and common environmental litter effects. Animals were reared during the fattening period (from weaning at 32 d of age to 60 d of age) in individual cages on an experimental farm, and were fed ad libitum with a commercial diet. Body weight (g) and cumulative feed intake (g) were recorded weekly. Individual BW gain (g) and average BW (ABW, g) were calculated from these data for each 7-d period. Metabolic BW (g(0.75)) was estimated as ABW(0.75). The number of animals actually measured was 444 and 445 in the Caldes and R lines, respectively. Marginal posterior distributions of the genetic parameters were obtained by Gibbs sampling. Posterior means (posterior SD) for heritabilities for partial coefficients of regression of feed intake on metabolic BW and feed intake on BW gain were estimated to be 0.35 (0.17) and 0.40 (0.17), respectively, in the Caldes line and 0.26 (0.19) and 0.27 (0.14), respectively, in line R. The estimated posterior means (posterior SD) for the proportion of the phenotypic variance due to common litter environmental effects of the same coefficients of regression were respectively, 0.39 (0.14) and 0.28 (0.13) in the Caldes line and 0.44 (0.22) and 0.49 (0.14) in line R. These results suggest that efficiency of use of feed resources could be improved by including these coefficients in an index of selection.  相似文献   
203.
A ureteral sarcoma was diagnosed in a nine-year-old Weimaraner dog with gross haematuria, severe unilateral hydronephrosis, and hydroureter. Treatment consisted of unilateral nephrectomy and ureterectomy. This case was compared with 14 other ureteral tumours reported in the veterinary literature. Only three previous reports concerned a malignant ureteral tumour. Urinary tract neoplasms mainly involve the bladder and the kidney, and more rarely the urethra. The purpose of this paper is to report a rare case of malignant ureteral tumour in a dog.  相似文献   
204.
Contagious bovine pleuropneumonia (CBPP), caused by Mycoplasma mycoides var. mycoides small colony (MmmSC), is one of the most important diseases of cattle in Africa. The role of innate or acquired cell mediated and humoral immunity in conferring protection against MmmSC infection has not yet been elucidated. On the other hand, the pathological lesions caused by the aetiological agent have been considered indicative of an immunopathological process. In this study ten na?ve cattle were exposed to in-contact infection with animals infected by intubation with a strain of MmmSC. Clinical signs, antibody response, IFNgamma release and pathological changes at necropsy were analysed and compared with the events following in-contact infection of an equal number of animals kept under daily treatment with cyclosporine for the entire observation period of 84 days. Cyclosporine is a suppressor of the immune response related to the T-cell system. Under the conditions of the experiment, cyclosporine appeared to condition the pathogenesis of CBPP by delaying the events that follow infection, bringing further support to the possibility that the immune response may have an impact on the disease outcome.  相似文献   
205.
The aim of this trial was to assess the effect that calcium gluconate priming of 468 broilers has on the antibacterial activity of a standard dose of enrofloxacin. Hence, a series of oral pharmacokinetic studies were carried out in four groups of broilers medicated individually through an oral cannula as follows: group A, medicated only with enrofloxacin 10mg/kg; group B, receiving immediately one after the other, calcium gluconate (200mg/kg) and enrofloxacin 10mg/kg; group C, dosed first with calcium gluconate (200mg/kg) and 1h later enrofloxacin (10mg/kg); and group D, dosed first with calcium gluconate (200mg/kg) and 2h later enrofloxacin (10mg/kg). Broilers were bled at different times after the dose of enrofloxacin and antibacterial activity, measured as concentration of enrofloxacin, was measured by an agar diffusion assay. Results revealed that group D the greatest values of maximum serum concentration (Cs(max)), area under the concentration vs. time curve (AUC) and area under the moment curve (AUMC). These values were statistically higher than the corresponding ones derived from groups A, B and C (P<0.05). Taking Cs(max) and AUC values of group A as reference baseline, an increase of 24% and 50%, respectively, was obtained in group D. Group B had the lowest Cs(max), AUC, AUMC and elimination half life (T(1/2)beta) and these values were statistically different from groups A, C and D (P<0.05). The T(1/2)beta was statistically longer in groups C and D as compared with A and B, and the former groups were also different between each other (P<0.05). These results show that if calcium gluconate is first dosed to broilers and 2h later enrofloxacin is administered (as in group D), a more pronounced antibacterial activity of enrofloxacin can be obtained. A challenge of this sequential dosing scheme in a field trial may reveal its clinical value.  相似文献   
206.
The toxic effects of an aqueous extract of Abrus precatorius were studied in 20 male white rats over a period of 18 days. The rats were divided into four groups of five rats per group. Those in Group A served as controls while the rats in Groups B, C and D were dosed per os with 400 mg/kg, 800 mg/kg and 1 600 mg/kg of the extract, respectively. Blood samples were collected for haematological and biochemical analysis and specimens of the liver, kidney and testes were taken for histopathological studies. The study showed that the extract of A. precatorius caused decreased levels of packed cell volume, haemoglobin concentration, red blood cell count, white blood cell count, mean corpuscular volume and mean corpuscular haemoglobin. The extract also resulted in increased levels of total serum protein, albumin, alanine amino transaminase, aspartate amino transferase, alkaline phosphatase and total bilirubin. Histologically, testicular degeneration characterized by decreased numbers of lining cells of the epithelium as well as reduction in sperm cells with presence of scattered Sertoli cells were noted. The study thus showed that aqueous extract of Abrus precatorius is toxic and caution should be exercised in its use for medicinal purpose.  相似文献   
207.
208.
The incidence of spinal cord (SC) injury in developed and undeveloped countries is alarming. The pig (Sus scrofa) has been recommended as a suitable research model for translational studies because of its morphophysiological similarities of organ systems with humans. There is a dearth of information on the SC anatomy of the large white and landrace crossbreed (LW-LC) pigs. We therefore aim to describe the gross morphology and morphometry of its SC. Twelve juvenile LW-LC pigs (six males and six females) were used. The skin and epaxial muscles were dissected to expose the vertebral column. The SC was carefully harvested by laminectomy, and 13 gross SC morphometric parameters were evaluated. Thirty-three spinal nerves were seen emanating from either side of the SC by means of dorsal and ventral spinal roots. The overall average of SC length and weight was 36.23 ± 1.01 cm and 16.60 ± 0.58 g, respectively. However, the mean SC length and weight were higher in females compared with males, with SC weight being statistically significant. A positive relationship between SC length and weight was significant for males (p = 0.0435) but not for females (p = 0.42). Likewise, the strength of the relationship between SC length and weight was significant in males (r = 0.82) but not significant in females (r = 0.41). Baseline data for the morphometric features of the spinal cord in the LW-LC pigs were generated, which will contribute to the knowledge of this species anatomy and useful information on regional anaesthesia that should further strengthen the drive in adopting the pig as a suitable research model for biomedical research.  相似文献   
209.
Irrigation systems aim to meet multiple objectives and performance must therefore be assessed using quantifiable measures for each. It therefore becomes an extremely difficult task to capture the valuation of all of them simultaneously and to mentally process the trade-offs between them in order to arrive at an overall impression of system performance. There is a need for a methodology which provides a systematic approach to comparing and combining the components of overall performance.Multi-Attribute Utility Theory offers an attractive approach to assessing performance of irrigation systems in the form of a utility function which reflects the strength of preferences and trade-offs between individual performance criteria. The method is described and demonstrated on the basis of a case study of irrigation in Sudan.  相似文献   
210.
In the High Plains, corn (Zea mays L.) is an important commodity for livestock feed. However, limited water resources and drought conditions continue to hinder corn production. Drought-tolerant (DT) corn hybrids could help maintain high yields under water-limited conditions, though consistent response of such hybrids is unverified. In this two-year study, the effects of three irrigation treatments were investigated for a DT and conventional maize hybrid, Pioneer AQUAMax P0876HR and Pioneer 33Y75, respectively. In 2013, the drier of the 2 years, irrigation amounts and crop water use (ETc) were greater for the conventional hybrid, but grain water use efficiency (WUE) and harvest index were significantly greater for the DT hybrid. In 2014, grain yields and WUE were not significantly different between hybrids. However, irrigation amounts, ETc and biomass yields were greater for the conventional hybrid. Results from both years indicate that the DT hybrid required less water to maximize grain yield as compared to the conventional hybrid. Producing relatively high yields with reduced amounts of water may provide a means for producers to continue corn production in a semiarid environment with declining water supplies.  相似文献   
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