Evaluation of the effects of enzootic pneumonia in pigs on weight gain and days to slaughter under New Zealand conditions     

Christensen NH 《New Zealand veterinary journal》1995,43(4):146-148

The effects of enzootic pneumonia on average daily weight gain and number of days taken to reach slaughter weight was studied in 333 bacon-weight pigs. Each 1% of lung volume affected by enzootic pneumonia was shown to reduce average daily gain by 2.2 grams and increase the numbers of days to slaughter by 0.61 days. The cost of these reductions in performance was calculated to be about NZD 1 for each 1% of lung affected.  相似文献   

Effects of air temperature, air movement and artificial rain on the heat production of brushtail possums (Trichosurus vulpecula): an exploratory study     

van den Oord QG  van Wijk EJ  Lugton IW  Morris RS  Holmes CW 《New Zealand veterinary journal》1995,43(7):328-332

Two groups of six mature brushtail possums (Trichosurus vulpeculu) were housed in two respiration chambers, and their heat production, whole body conductance and lower critical temperatures were measured under a variety of simulated weather patterns. The possums were subjected to ambient temperatures of 30, 20 and 3 degrees C. At 20 and 3 degrees C, the animals were exposed to near still air and light winds (wind speed 0.8 and 6.7 km/h), both with, and without, simulated rain every 8 hours. The lower critical temperature in near still air lies between 7 and 10 degrees C. This temperature increases by about 2, 6 and 8 degrees C respectively for a wind velocity of 6.7 km/h, simulated rain and a combination of the two factors. Weather in New Zealand, especially in the cooler part of the year, will often produce conditions below the lower critical temperature of the thermoneutral zone of possums. This will necessitate significant increases in metabolic rate and hence food consumption or mobilisation of body fat reserves, which if not sustainable will result in the death of possums. Field studies have shown that this is often the case in the wild. It is proposed that this stress may be sufficient to decrease the resistance (especially cell-mediated immunity) of some possums and allow acceleration of the disease process in those infected with Mycobacterium bovis.  相似文献   

The distribution of gross lesions of tuberculosis caused by Mycobacterium bovis in feral ferrets (Mustela furo) from Otago, New Zealand     

Ragg JR  Waldrup KA  Moller H 《New Zealand veterinary journal》1995,43(7):338-341

The distribution of gross lesions of Mycobacterium bovis was examined in 94 tuberculous feral ferrets (Mustela furo) collected from 1992 to 1995 from areas of Otago endemic for bovine tuberculosis. Overall, 56.4% of tuberculous ferrets had single-site lesions, 24.5% had multiple infections and 19.1% had generalised infections. The mesenteric lymph node was the most common site of infection (34.5% of all lesions), with the retropharyngeal (17%) and the prescapular lymph nodes (16.4%) also frequently infected. Only 2.9% of lesions involved the respiratory tract. Of single-site lesions, 60.4% were in the mesenteric lymph node. The high proportion of lesions in the alimentary tract suggests that the ingestion of infectious material, possibly carrion or prey, is an important source of infection. Peripheral lymph nodes contributed to 24.5% of all infections, suggesting that within species transmission by social contact such as fighting and mating also occurs. Open and respiratory lesions were found in 11.7% of tuberculous ferrets, which suggests that ferrets are potentially infectious and therefore may be involved in the transmission of bovine tuberculosis to domestic stock and other mammals. The distribution of gross M. bovis lesions in ferrets is compared to those observed in possums (Trichosurus vulpecula) and badgers (Meles meles).  相似文献   

A survey of the selenium status of beef cows in Alberta.   总被引：1，自引：1，他引：0  

J R Campbell  G K Jim  C W Booker    P T Guichon 《The Canadian veterinary journal. La revue veterinaire canadienne》1995,36(11):698-702

An epidemiological survey was conducted in Alberta to measure the selenium status in blood of beef cows during the fall and to determine the risk of selenium deficiency among specific geographic regions of Alberta. Three census divisions of Alberta based on the Statistics Canada Census of Agriculture were chosen as the study areas for the project. Soils and plants in area A (Edmonton area) and area B (Calgary area) were known to be deficient in selenium, while soils and plants in area C (southeast corner of Alberta) were known to have adequate levels of selenium. Blood samples were collected from 335 cows on 29 farms from the 3 study areas. These samples were collected from cows that had recently been removed from pasture in October and November 1992. Answers to a short questionnaire pertaining to various herd characteristics and management practices were also obtained for each herd. The average value of selenium for all cows sampled was 2.20 mumol/L. The average value of selenium of cows in areas A and B was 1.93 mumol/L. The average value of selenium of cows in area C was significantly (P < 0.05) higher at 2.70 mumol/L. Nine percent of the cows in the study were considered marginal or deficient in selenium (< 1.27 mumol/L selenium). Herds located in area C, herds that were provided with supplemental feed on pasture, and herds that were pregnancy checked had higher average herd selenium values than did other herds. Cow-calf producers located in areas with selenium-deficient soils should pay particular attention to selenium supplementation for their cows. Some of the negative "geographic" effects on selenium values can be overcome by more progressive management practices.  相似文献   

Eosinophilic papulocrustous dermatitis (miliary dermatitis) and eosinophilic inflammatory bowel disease in two cats     

Bell AG  Chard WG  Grayson JL  James MP 《New Zealand veterinary journal》1995,43(4):153-157

Two cats with chronic eosinophilic skin disease were investigated. The clinical investigation of the skin disease in one cat was limited and inflammatory bowel disease was diagnosed post mortem. A history of weight loss and a palpably thickened bowel in the second cat suggested concurrent gastrointestinal disease. Diagnosis of inflammatory bowel disease was confirmed on biopsy. Treatment with azathioprine and methylprednisolone acetate resolved the signs of gastrointestinal disease, the pruritus and 95% of the skin lesions. The concurrence of eosinophilic papulocrustous dermatitis and eosinophilic bowel disease raises the possibility of their being linked bv a common aetiology or pathophysiology.  相似文献   

Evidence that the eumelanin restrictor genes (Co) and (Db) are present in the genome of the Buff Rock bantam     

W. C. Carefoot 《British poultry science》1995,36(2):205-207

1. An investigation was conducted among the progeny from crosses between Buff Rock and Light Sussex bantams, and between Buff Rock and Gold‐Pencilled Hamburgh bantams in order to ascertain whether the eumelanin restrictor genes Columbian (Co) and Dark‐brown (Db) were present in the genome of the Buff Rock.

2. The Light Sussex and Gold‐Pencilled Hamburgh bantams used in this study were known to be Co/ Co db⁺ / db⁺ and co⁺ / co⁺ Db/ Db respectively.

3. In both F₂ generations the least eumelanin restricted segregants were as the parent mated with the Buff Rock, thus demonstrating the Buff Rock bantam tested to be Co/ Co Db/ Db, or possess similar alleles at these loci.

4. The Buff Rock bantam male was found to be heterozygous for a eumelanin inhibitor gene which appears to be dominant white (I).  相似文献   

Dynamics ofRhizoctonia solani (black scurf) in successive potato crops     

G. Jager  H. Velvis 《European journal of plant pathology / European Foundation for Plant Pathology》1995,101(4):467-478

The position of plants withRhizoctonia solani sclerotia (black scurf) on progeny tubers was mapped for an experimental field at Haren where potatoes were grown continuously and in rotation with other crops for five successive years, and for another field at Borgercompagnie with a 12 frequency of potatoes during three potato crops. Initially, the distribution of plants with black scurf on both fields was rather dense and homogeneous. In the following years the distribution became heterogeneous and patchy. The local decline ofR. solani AG 3 (the common potato pathogen) in Haren was apparently caused by an unknown factor selectively suppressingR. solani AG 3, while simultaneouslyR. solani AG 5 increased in mass. This AG 5 type proved to be an inferior competitor of AG 3 on the potato plant in a laboratory experiment. The specificR. solani antagonistVerticillium biguttatum did not play a role. A similar factor could have reduced the formation of black scurf in the experimental field at Borgercompagnie, whereV. biguttatum was also too infrequent to account for the decline.R. solani AG 5 was not present here and could not indicate the presence of a selective factor against AG 3.  相似文献   

The mohole project     

Bascom W 《Science (New York, N.Y.)》1984,226(4671):114

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Ultrahigh Sensitivity from GC-IR     

Maugh TH 《Science (New York, N.Y.)》1984,224(4644):42

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The Agricultural Sector in China: Agriculture in China's Modern Economic Development     

Calkins PH 《Science (New York, N.Y.)》1984,224(4650):713-714

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