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21.
Subcutaneous clostridial infection in broilers   总被引:2,自引:0,他引:2  
A flock of 12,500 broilers 36 days of age experienced a sudden increase in mortality. Post-mortem lesions were emphysema, severe enteritis, and a serosanguineous fluid in the subcutaneous tissue of the breast and thighs; there was no evidence of a loss in the integrity of the skin. Clostridium perfringens and C. septicum were isolated from the affected subcutaneous tissue. Histopathological and serological examination indicated previous infection with infectious bursal disease virus. The subsequent immunosuppression and severe enteritis may have permitted the clostridia access to the circulatory system, with localization in the subcutaneous areas of the breast and thighs. Mortality returned to normal 48 hours after potassium penicillin G was administered via the drinking water.  相似文献   
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The objectives of this study were to determine effects of cyfluthrin and pyrethrin spray products, used in combination with cyfluthrin topical and ear tag applications, on bull reproductive parameters over 18 weeks. Angus or Angus x Simmental bulls were randomly assigned to one of three treatment groups: (i) no exposure to pyrethrins/cyfluthrin (CONT; n = 10), (ii) cyfluthrin ear tag and topical applications (ET; n = 10), or (iii) cyfluthrin ear tag, topical, premise spray and pyrethrin fog spray applications (ET+S; n = 8). Bull body weight was measured every 3 week, and body condition score and scrotal circumference were recorded on weeks 0, 9 and 18. Semen and serum were collected every 3 weeks for sperm evaluation and testosterone measurement, respectively. There was a treatment × week interaction (p < 0.01) for sperm with primary defects; bulls in CONT group had a greater (p = 0.01) percentage of sperm with primary defects than bulls treated with insecticides at week 18. Overall and progressive sperm motility, normal sperm morphology, secondary sperm defects and serum testosterone concentrations changed (p < 0.01) over time in all bulls; however, treatment did not affect (p ≥ 0.13) any of these parameters. There were also no treatment effects (p ≥ 0.08) on bull body weight, body condition score or scrotal circumference. The use of pyrethrin‐ and cyfluthrin‐based insecticides, regardless of application, did not negatively affect reproductive parameters in beef bulls when administered over 18 weeks.  相似文献   
24.
Livestock excreta is one of the major nutrient sources in natural grasslands. Understanding how livestock diet and season affects the decomposition dynamics is critical to nutrient cycling models. We hypothesised that livestock diet and season of the year affect dung decomposition. This study evaluated the decomposition and release of N, P, K, Ca, Mg, and Na from faeces of cattle collected in dry and wet seasons. Treatments were signalgrass (Brachiaria decumbens Stapf) in monoculture or mixed with sabiá (Mimosa caesalpiniifolia Benth.) or gliricidia (Gliricidia sepium (Jacq.) Kunth ex Walp.). Excreta samples were incubated in nylon bags for 0, 2, 4, 8, 16, 32, 64, 128 and 256 d. The single negative exponential mathematical model was adequate (P < 0.0001) to explain the decomposition. The relative rate of dung decomposition (k) was greater for samples that originated from cattle grazed on signalgrass (k = 0.00284 g g?1 d?1), followed by sabiá (k = 0.00233 g g?1 d?1), and gliricidia (k = 0.00200 g g?1 d?1) pastures. The rate of nutrient release showed a time effect for all variables and interaction between time and season for Ca (P = 0.0042) and Mg (P = 0.0013). Faeces collected from cattle grazing/browsing intercropped pastures tended to have lower decomposition rates.  相似文献   
25.
AIM: To determine the frequency and type of skin wounds encountered by New Zealand veterinarians in their equine patients, the duration and estimated costs of treatment as well as the expected outcomes for these wounds.

METHODS: An online survey was sent to all veterinarians registered with the New Zealand Equine Veterinary Association. The survey comprised questions on the location and experience of respondents, the number of wound-related cases in relation to the total equine caseload, the type and anatomical location of wounds treated, the frequency, duration and costs of treatments, the outcome of wound treatment and an estimate of the most common causes of death or euthanasia in their equine patients.

RESULTS: The survey response rate was 110/262 (41.9%). The median number of equine cases seen by respondents was 20 (interquartile range (IQR) 6–60) per month; of these, five (IQR 2–10) were wound related. Wounds ranked third after lameness and respiratory disease for the relative frequency with which respondents encountered them. Of 102 respondents 59 (58%) reported that their clients frequently treated wounds incurred by their horse without consulting a veterinarian. Wounds on the distal limb, whether involving only the skin or also deeper structures, were reported by 86/101 (85%) respondents as the most frequently encountered. Wounds in this location also incurred the longest treatment period and were the most prone to develop complications. Finally, wounds ranked second, after colic, as the most common cause of death/euthanasia in the veterinary respondents’ equine patients.

CONCLUSIONS: The data obtained via the survey indicate that skin wounds, particularly on the distal limb, are a common occurrence in horses in New Zealand and, when they involve structures underlying the skin, are costly and time-consuming to manage and may lead to decreased performance, retirement or euthanasia. Consequently, we recommend that more effort be devoted to the education of equine veterinarians and owners, and that appropriate research funds be allocated to help improve patient outcomes.  相似文献   

26.
Congenital luxation of the ulnar and radius is a rare orthopaedic condition in the dog. This case report describes a novel surgical treatment for congenital elbow luxation in a medium-breed dog. A 6-week-old Kelpie presented for left forelimb lameness and deformity. Radiographs and computed tomography (CT) confirmed the diagnosis of unilateral ulnar and radius luxation. The surgical repair involved open reduction followed by fixation with an extraarticular pin and a transarticular external fixator. The outcome of surgery was improved leg function and weight-bearing, however, reluxation of the radial head was diagnosed 7 weeks following surgery. This technique may offer an alternative surgical option to improve clinical signs, as well as insight into improving the management of this condition.  相似文献   
27.
The poultry industry is a highly complex food-animal production system. Its success is dependent upon sophisticated techniques and systems to ensure disease prevention and product quality. Poultry veterinarians play a key role in the overall business and are typically the only individuals within poultry companies who are involved in the entire production process, including production management, health management, product quality, nutrition, and economics. Preparing veterinarians to work effectively in the poultry industry can no longer be accomplished within the DVM instructional program. Post-DVM training programs specializing in poultry medicine are now producing the veterinarians entering the North American poultry industry. Regionalization of training in poultry medicine has already taken place. These training programs are very important to food animal production in North America; in the future, they must be nurtured and supported in order to remain able to supply the veterinary workforce for our dynamic poultry industry.  相似文献   
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Day-old broiler chicks (n=30) were obtained from a commercial hatchery and inoculated, either orally or intracloacally, with a characterized strain of Campylobacter jejuni. At 1 hr, 1 day, and 1 wk after inoculation, broilers (n = 5) from the orally and intracloacally inoculated groups along with control birds (n=4) were humanely killed by cervical dislocation. The broilers from the control and treatment groups were aseptically opened, and the thymus, spleen, liver/gallbladder, bursa of Fabricius, and ceca were aseptically removed and individually analyzed for C. jejuni. Overall, C. jejuni was isolated after oral inoculation from 13% (10/ 75), 17% (13/75), and 28% (14/50) of the 1-hr, 1-day, and 1-wk samples, respectively. Campylobacter jejuni was isolated from 10% (4/ 40), 8% (3/40), 10% (4/40), 25% (10/40), and 40% (16/40) of the thymus, spleen, liver/gallbladder, bursa of Fabricius, and ceca samples, respectively. Following the intracloacal route of inoculation, C. jejuni was recovered from 32% (24/75), 8% (6/75), and 16% (8/50) of the 1-hr, 1-day, and 1-wk samples, respectively. Campylobacter jejuni was isolated from 5% (2/40), 5% (2/40), 5% (2/40), 45% (18/40), and 40% (16/40) of the thymus, spleen, liver/gallbladder, bursa of Fabricius, and ceca samples, respectively, for all sampling periods. Campylobacter spp. were not recovered from sample sites examined from the control broilers from trial one, trial two, or trial three samples examined after 1 hr and 1 day. However, one control sample was positive from the 1-wk sampling from repetition three; therefore, those data were omitted. The rapid movement of Campylobacter to internal organs following both oral and intracloacal inoculation may be significant, particularly if it persists in these organs as reservoirs throughout the 65-wk life cycle of breeding birds.  相似文献   
30.
Concern by consumers about food safety has resulted in increased pressure on poultry companies to develop effective sanitation programs. Salmonella isolates in hatcheries are often the same species isolated from processing plants. Resistance develops in bacteria after prolonged exposure to disinfectants. The methods available in published literature to detect the efficacy of disinfectants are labor intensive and do not consider how bacteria behave when adhered to a solid surface. We used a recently developed technique, which utilizes the actual surfaces on which the disinfectant is to be applied, to evaluate the degree of resistance to four commercially available disinfectants of 17 bacterial isolates from poultry hatcheries. We found that bacterial isolates within the same genus and species have different sensitivities to the same disinfectant. In addition, disinfectants with similar but not identical chemical formulations have different efficacies against the same bacteria.  相似文献   
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