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31.
32.
Michael H. Woodford 《Tropical animal health and production》2009,41(7):1023-1033
Proliferation of disease pathogens capable of affecting humans, domestic livestock and wildlife increasingly threatens environmental
security and biodiversity. Livestock and wild animals in proximity to human beings are often in the chain of transmission
and infection. Globalization of industrial livestock production (especially poultry upon which so much of the burgeoning human
population depends) often permits transcontinental disease spread. Rapidly expanding (and often illegal) international trade
in wild and domestic animals and their products are increasingly involved in the emergence of new diseases that may have the
ability to transmit among humans, livestock and wildlife. Rapidly increasing urbanization has led in many places to overcrowded
townships that rely on “bushmeat” for sustenance and has contributed to the emergence of virulent zoonotic pathogens. The
emergence and proliferation of pathogens are exacerbated by anthropogenic transformation of natural landscapes in order to
increase agricultural and livestock production. This paper posits that data gathered by veterinary ecologists should be interpreted
and used by other disciplines. The importance of a thorough knowledge of the “natural history” (ecology) of the disease agent
and its human, domestic and wild hosts is stressed. 相似文献
33.
Research in control of tick-borne diseases and trypanosomosis, and their vectors, namely, ticks and tsetse flies respectively,
has been on going for decades. However, very little attention has been paid to the socio-economic factors that are likely
to influence the outcome of the interventions in the control of these diseases. Thus, this study was designed to investigate
these factors, mainly the intra-household factors influencing decision-making in the control of Vector-borne diseases in the
pastoralist areas of Uganda. These factors included: indigenous technical knowledge, household economic factors, and gender.
Both qualitative and quantitative methods were used in the collection and analysis of data. The tools used for data collection
included among others, participatory learning and action (PLA), and Case studies. The findings included the following: In
pastoralist households, a big proportion of the household budget was allocated to vector-borne diseases control. In the male-headed
households, men dominated decision-making on vector-borne diseases control, although the goals and priorities of men and women
in these households were not the same. Also, vector-borne disease control was predominantly by use of modern veterinary drugs,
and pastoralists treated sick cattle by themselves even in situations where there were veterinary personnel. 相似文献
34.
35.
Abiodun A. Adesiyun Geoff T. Fosgate Anil Persad Mervyn Campbell Ravi Seebaransingh Alva Stewart-Johnson 《Tropical animal health and production》2010,42(8):1685-1694
The preliminary study was conducted to assess the virulence of a strain of Brucella abortus (1969D) and to compare the susceptibility of water buffalo and cattle calves to infection by the intraconjunctival route.
Seven of each cattle and water buffalo (Bubalus bubalis) calves aged 3–6 months were inoculated intraconjunctivally with counts ranging from 1.5 × 107 to 1.7 × 1010 colony forming units of B. abortus. Animals were monitored over an 8-week period for clinical manifestations and serological and hematological evidence of infection.
At slaughter, eight lymph nodes from each animal were sampled for bacteriological and histopathological assessments. Lymph
nodes from three water buffalo (43%) and five cattle (71%) yielded B. abortus (P = 0.048). Parotid/prescapular lymph nodes were most sensitive in detecting B. abortus. Our data suggest that B. abortus strain 1969D may be used as challenge strain, and water buffalo appeared to have a lower susceptibility to B. abortus infection than cattle. 相似文献
36.
Shahbazfar AA Mardjanmehr SH Arab HA Rassouli A Abdollahi M 《Tropical animal health and production》2011,43(4):843-849
Artemisinin has been used for centuries to treat malaria, intestinal tract helminthosis, diarrhea, and used as an antipyretic
and sedative agent, but the usage in veterinary medicine is a new field. Recently, it has been used successfully to control
experimental poultry coccidiosis. The present study aimed to determine the effects of different doses of artemisinin in broiler
chickens with chronic usage. Sixty birds divided into one control and four treatment groups that fed rations mixed with artemisinin
at doses of 17, 34, 68, and 136 ppm for 36 days. During the experiment, birds showed no clinical signs except anemia. In microscopic
examinations, heart, lung, and spleen had no lesion, but liver, kidney, and brain showed various lesions. Degenerative lesions
like intracytoplasmic eosinophilic inclusions were seen in both kidney and liver but fatty change was seen only in liver.
There was no relationship between severity of the liver lesions and drug dosage. Central chromatolysis, scattered neuronal
necrosis, and mild spongy changes were observed in five regions of the brain that were chosen for sectioning (motor cortex,
cerebellar nuclei, midbrain nuclei, and hindbrain nuclei at two separate levels). Severity of lesions in brain was dose-dependent,
and cerebral cortex was the most vulnerable area. Haematologic tests showed lower values for hematocrit and red blood cell
count dose-dependently. In conclusion, artemisinin is a promising drug for prevention and control of coccidiosis in broiler
chickens and its side effects are not too much serious especially at therapeutic doses. 相似文献
37.
E S Berry D E Skilling J E Barlough N A Vedros L J Gage A W Smith 《American journal of veterinary research》1990,51(8):1184-1187
A new serotype of calicivirus was isolated from California sea lions (Zalophus californianus) with severe vesicular disease. Neutralizing antibodies were found in 27 of 82 (32.9%) serum samples from California sea lions and in 15 of 146 (10.3%) serum samples from Steller sea lions (Eumetopias jubatus) tested. The seropositive animals were widely dispersed along the margins of the eastern Pacific basin, from the Bering Sea to the Santa Barbara Channel. Seropositive samples were found from as early as 1976 through the present time. This new calicivirus serotype, San Miguel sea lion virus type 13, was inoculated into weaned pigs, resulting in induction of severe vesicular disease, which spread to all pigs, including uninoculated pen contacts. Virus was continually shed by most of the pigs throughout the 2-week duration of the experiment. 相似文献
38.
Reena Kamal Triveni Dutt Manjunath Patel Amitava Dey Panch Kishore Bharti Poolangulam Chinnakkan Chandran 《Tropical animal health and production》2018,50(4):701-706
In tropical countries, at high temperatures, several physiological rearrangements occur in cows as they attempt to facilitate heat dissipation and/or reduce metabolic heat production. Following exposure to heat, cattle appear to acclimatize within 2–7 weeks. The failure of homeostasis at high temperatures may lead to reduced productivity or even death. The situation is even worse when humidity adds to high temperature. Livestock with elevated body temperature exhibit lower DMI and growth with less efficiency, reducing profitability for dairy farms in hot and humid climates. Shading of feed and water also offers production advantages. Although several elaborate methods for reducing heat stress in cows have been reported, simple shade materials appear to be the most cost-effective methods that are currently applicable to tropical developing countries. Different materials are being used to provide shade during warm weather. The shade material determines the microclimate—it should be light, strong, durable, weatherproof, good looking and a bad conductor of heat, and free from tendency to condense moisture inside. This review discusses various shade materials and their advantages and disadvantages in different situations. 相似文献
39.
After very hot summer, 22 sheep from 5 different flocks consisting of approximately 150-200 animals each were diagnosed with facial eczema in September 2005, in southwest Turkey. Photophobia, corneal opacity, severe ulcers of the facial skin, especially localized around the eyes and mouth, and 3% mortality were the most prominent clinical symptoms. GGT levels of the animals were very high and varying between 261- 328 U/l. While the activities of ALT and total bilirubin were elevated and AST was normal in affected sheep. Total bilirubin level was higher than normal. Seven of the 22 sheep were euthanatized and necropsy was performed on all of these animals. Severe icterus, hepatomegaly, enlarged gallbladder, congestion of mesenteric vessels were the common necropsy findings. Histopathological changes of the liver included necrosis of the hepatocytes, cholangiohepatitis characterized by mononuclear inflammatory cell infiltrate in the portal area and mild to severe fibrosis around bile ducts. A diagnosis of sporidesmin toxicosis was made based on the histopathology of the livers, the elevation in liver enzymes, and the development of cutaneous lesions consistent with photosensitization and high spore counts in the ruminal contents. Surviving sheep were treated with procaine penicillin + dihidrostreptomycin sulfate, multivitamin complexes and flunixin meglumine. Additionally, zinc sulphate was also given at a dose of 6 gr per 100 lt drinking water for 28 days. All treated sheep recovered. Pasture spore counts were between 96,300- 267,500 spores/g grass. 相似文献
40.
Hawkins EC Basseches J Berry CR Stebbins ME Ferris KK 《Journal of the American Veterinary Medical Association》2003,223(11):1628-1635
OBJECTIVE: To determine demographic, clinical, and radiographic features of bronchiectasis in dogs. DESIGN: Retrospective study. ANIMALS: 289 dogs identified through the Veterinary Medical Database (VMDB) and 27 dogs examined at the North Carolina State University Veterinary Teaching Hospital. PROCEDURE: Demographic characteristics of dogs identified through the VMDB were compared with characteristics of the entire population of dogs entered in the VMDB. Medical records of dogs examined at the teaching hospital were reviewed; the diagnosis was confirmed through review of thoracic radiographs. RESULTS: Analysis of data from the VMDB indicated that American Cocker Spaniels, West Highland White Terriers, Miniature Poodles, Siberian Huskies, English Springer Spaniels, and dogs > 10 years old had an increased risk of bronchiectasis. Among dogs examined at the teaching hospital, coughing was the most common clinical sign. There was evidence for excessive airway mucus but not hemorrhage. A variety of bacterial organisms were isolated from tracheal wash and bronchoalveolar lavage samples. On thoracic radiographs, cylindrical bronchiectasis, generalized disease, and right cranial lung lobe involvement were most common. Seven of 14 dogs for which follow-up radiographs were available did not have any progression of radiographic lesions. Median duration of clinical signs prior to diagnosis of bronchiectasis was 9 months (range, 1 day to 10 years). Median survival time was 16 months (range, 2 days to 72 months). CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that despite substantial clinical abnormalities, dogs with bronchiectasis may survive for years. Certain purebred dogs and older dogs may have an increased risk of developing bronchiectasis. 相似文献