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51.
Systemic and secretory antibody responses to sequential bovine respiratory syncytial virus infections in vaccinated and nonvaccinated calves 总被引:1,自引:0,他引:1
To investigate the influence of humoral immunity on the severity of disease caused by infection with bovine respiratory syncytial virus (BRSV), an experimentally induced infection study was performed on vaccinated and nonvaccinated calves. Fifteen weanling calves were allotted to 3 groups: 1 group of 6 calves was exposed to 2 live virus aerosols, 35 days apart; another group of 6 calves was vaccinated prior to the same aerosol exposures; and the remaining 3 calves served as controls. Clinical signs of infection were converted to a numerical score for evaluating disease severity. For 14 days after each virus exposure, BRSV-specific IgG and IgM concentrations in serum and BRSV-specific IgA concentration in nasopharyngeal exudate and lung lavage fluid were measured by ELISA. Serum BRSV-specific IgG and IgM and secretory BRSV-specific IgA concentrations did not correlate with disease sign expression. There was a strong correlation between viral isolation and disease scores. Vaccination prior to virus exposure appeared to have little or no effect on severity of the disease, but it did appear to affect disease persistence. Findings indicate that the immunoglobulins evaluated may be primarily protective in nature and do not contribute to disease severity. 相似文献
52.
Millogo V Norell L Ouédraogo GA Svennersten-Sjaunja K Agenäs S 《Tropical animal health and production》2012,44(5):1017-1025
The aim of the study was to test three different hand-milking techniques (“pull down”, “thumb in”, and “full hand grip”) and
their effects on milk production and teat treatment. This is important since milk production in many tropical areas still
rely on hand-milking. The study was carried out at a peri-urban farm in the Bobo-Dioulasso area in Burkina Faso. Twelve indigenous
Zebu cows in early lactation were used in the study. The sequences of the treatments (hand-milking techniques) and the milkers
were balanced for carry-over effects between successive periods and days, respectively. The sequences were constructed by
using special Latin squares. Yield and composition of saleable milk was not affected by milking technique but there were differences
between the milkers in milk yield. There was also a significant interaction for saleable milk yield between milker and milking
technique. Hemoglobin in milk was measured as an indicator of teat damage. The hemoglobin content was numerically higher in
post-milking strip milk samples than in saleable milk. It was concluded that the amount of milk removed depends mainly on
the milker and how well the milking technique works for the individual milker. No effect of milking technique was observed
on teat treatment. 相似文献
53.
54.
55.
A longitudinal study was done to monitor incidence of livestock diseases in ranch and pastoral herds around Lake Mburo National
Park, in South-western Uganda with a high level of wildlife (impala and zebra) and livestock (cattle and goats) interactions.
East Coast Fever (ECF), abortions, helminthosis and starvation due to drought were major livestock disease problems encountered.
ECF was a major disease affecting mainly calves, causing mortality both in ranch (8.5%) and pastoral (8.2%) herds. Meanwhile,
drought was a more serious in pastoral than ranch herds (p < 0.05), killing 28.5 % and 5.8% of adult female cattle in respective
production systems. Other endemic diseases found and controlled by vaccination were FMD, CBPP and blackquarter. In both cattle
and goats helminthosis was causing mortalities, 3.3% and 0.8% among calves in pastoral and ranches respectively; and 4.8%
and 6.9% among kids and sub-adult goats respectively. Many cases of abortions occurred among pastoral herds. In conclusion,
the disease incidence among livestock was the same or relatively low as compared to other areas without wildlife. 相似文献
56.
T. Reg Preston 《Tropical animal health and production》2009,41(7):1071-1080
Responding to the challenges posed by global warming, peak oil and biofuels will require a paradigm shift in the practice
of agriculture and in the role of live stock within the farming system. Farming systems should aim at maximizing plant biomass
production from locally available diversified resources, processing of the biomass on farm to provide food, feed and energy
and recycling of all waste materials. The approach that is the subject of this paper is that the generation of electricity
can be a by-product of food/feed production. The concept is the fractionation of biomass into inedible cell wall material
that can be converted to an inflammable gas by gasification, the gas in turn being the source of fuel for internal combustion
engines driving electrical generators. The cell contents and related structures such as tree leaves are used as human food
or animal feed. As well as providing food and feed the model is highly appropriate for decentralized small scale production
of electricity in rural areas. It also offers opportunities for sequestration of carbon in the form of biochar the solid residue
remaining after gasification of the biomass. 相似文献
57.
Oliveiro Caetano de Freitas Neto Sonia Luisa Silva Lages Adriano Oliveira Torres Carrasco Angelo Berchieri Junior 《Tropical animal health and production》2009,41(8):1607-1614
We analyzed ostriches from an equipped farm located in the Brazilian southeast region for the presence of Salmonella spp. This bacterium was investigated in 80 samples of ostrich droppings, 90 eggs, 30 samples of feed and 30 samples of droppings
from rodents. Additionally, at slaughter-house this bacterium was investigated in droppings, caecal content, spleen, liver
and carcasses from 90 slaughtered ostriches from the studied farm. Also, blood serum of those animals were harvested and submitted
to serum plate agglutination using commercial Salmonella Pullorum antigen. No Salmonella spp. was detected in any eggs, caecal content, liver, spleen, carcass and droppings from ostriches and rodents. However,
Salmonella Javiana and Salmonella enterica subsp. enterica 4, 12: i:- were isolated from some samples of feed. The serologic test was negative for all samples. Good sanitary farming
management and the application of HACCP principles and GMP during the slaughtering process could explain the absence of Salmonella spp. in the tested samples. 相似文献
58.
Marco Pietra Renato Giulio Zanoni Angelo Peli Barbara Brunetti Nikolina Linta Ombretta Capitani Giuseppe Spinella 《Irish veterinary journal》2015,69(1):12
Background
The authors report the first case of feline gastric actinomycosis associated with infection by Actinomyces hordeovulneris.Case presentation
A 4-year-old, neutered male, semi-feral European cat, with a 1 year history of chronic vomiting, was referred to the clinic. Abdominal ultrasound examination identified a hypoechoic focal transmural thickening with loss of normal wall layering and hyperechoic speckles at the gastric body. Initial gastroscopic examination showed a tumour-like gastric mass with an ulcerated depression at the level of the greater curvature. Histologic examination of endoscopic biopsy specimens was consistent with a severe lymphoplasmacytic gastritis. After 2 months, due to persistence of abdominal discomfort, surgical exploration and intraoperative sampling of gross abnormalities was recommended. Full thickness gastric wall biopsies, and fine needle aspiration of the gastric thickening and gastric lymph node, were performed. Histopathological examination identified a transmural pyogranulomatous gastritis. Aspirate samples of the gastric wall cultured positive, with colony morphology, biochemical testing and PCR of the 16 s rRNA gene compatible with Actinomyces hordeovulneris. After 4 months of treatment with cefovecin (8 mg/kg subcutaneously every 14 days), the vomiting completely resolved, as well as the ultrasonographic gastric alteration.Conclusion
This case report of feline gastric actinomycosis, caused by Actinomyces hordeovulneris, suggests that gastric bacterial infection should be considered in cases of focal gastric wall thickening associated with chronic vomiting in the cat, which may otherwise closely resemble neoplastic disease. Once a diagnosis of actinomycosis was obtained, a correct treatment with antibiotic therapy can resolve it.59.
Stewart SA Gaunt MC Taylor SM Snead EC 《The Canadian veterinary journal. La revue veterinaire canadienne》2010,51(9):1003-1006
Two clinical cases of accidental entrapment of cats in front-loading washing machines are described. One cat died the day after presentation as a result of aspiration pneumonia and head trauma, despite supportive care. The second cat survived with supportive treatment, but developed dermatologic complications 10 d later. 相似文献
60.
A cross-sectional survey was conducted in Sudan to determine sero-prevalence and risk factors associated with Neospora caninum infection in non-vaccinated dairy herds and to assess importance of the disease. Blood samples were collected from a total
of 262 animals from 25 herds. Sera were tested for antibodies against N. caninum using ELISA test. The prevalence rates of N. caninum antibodies in cattle were high both at herd level (44%) and at individual animal level (10.7%). Herd level infection rates
were similar in Khartoum State (43.7%) and at Gazira States (44.4%). The overall prevalence rates were higher (16.1%) in Gazira
State than in Khartoum State (9%) but with no significant variation. The sero-prevalence at individual animal level was significantly
higher (p < 0.05) in animals with history of abortion (12.8%) than in apparently healthy animal (11.3%), animal with history of infertility
(8.1%), or neonatal death of calves (4.3%). In addition, significantly higher (P < 0.05) sero-prevalence was observed in samples collected during the rainy season (6.87%) than winter (3.05%) or summer (0.76%).
However, no significant differences in sero-prevalence due to locality, animal breed, sex, and age were observed (p > 0.05). This preliminary study reveals for the first time the existence of natural N. caninum infection in Sudan. Also, the findings of the present study indicated that this disease is highly prevalent in two major
areas of dairy production in the country, and this calls for control strategy to be implemented. 相似文献