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41.
42.
Equine protozoal myeloencephalitis (EPM) is a serious neurological disease of horses in the Americas. The protozoan most commonly associated with EPM is Sarcocystis neurona. The complete life cycle of S. neurona is unknown, including its natural intermediate host that harbors its sarcocyst. Opossums (Didelphis virginiana, Didelphis albiventris) are its definitive hosts. Horses are considered its aberrant hosts because only schizonts and merozoites (no sarcocysts) are found in horses. EPM-like disease occurs in a variety of mammals including cats, mink, raccoons, skunks, Pacific harbor seals, ponies, and Southern sea otters. Cats can act as an experimental intermediate host harboring the sarcocyst stage after ingesting sporocysts. This paper reviews information on the history, structure, life cycle, biology, pathogenesis, induction of disease in animals, clinical signs, diagnosis, pathology, epidemiology, and treatment of EPM caused by S. neurona.  相似文献   
43.
Amoeboid movement of spheroid or ovoid immature or mature macrogamonts within cultured Madin-Darby bovine cells usually began with the formation of a pseudopodium-like protrusion at the margin of the gamont. The protrusion enlarged as the gamont cytoplasm and nucleus moved into the protruded area. During movement, macrogamonts had an elongate shape. The body of the gamont was constricted as it moved through the cell cytoplasm or from one cell to an adjacent one. After movement had ceased, the gamont resumed its ovoid or spheroidal shape.  相似文献   
44.
Six mature Yorkshire X Landrace sows were randomly assigned to a 6 X 6 Latin-square experiment on d 5 of lactation to determine the total phenylalanine (Phe) and tyrosine (Tyr) requirement. A control diet of corn sugar, cornstarch, whey, L-glutamic acid, solka floc, soybean oil, amino acids, minerals and vitamins was supplemented with L-Phe to provide .30 (basal), .45, .60, .75, .90 and 1.05% total aromatic amino acids (TAAA). Each diet was fed to a maximum of 5.5 kg/d within each of six 10-d periods. Feed intake, average pig weight gain and sow milk yield decreased linearly (P less than .01) with increasing period. Sow milk yield was maximized at .75% TAAA (quadratic, P less than .10), but average pig weight gain did not reflect the higher yield. Urea nitrogen decreased quadratically with increasing dietary Phe in both plasma (P less than .05) and urine (P less than .01) to a breakpoint at .56% TAAA. Plasma Phe increased (quadratic, P less than .01) as dietary TAAA increased, but no clear inflection point was obtained. A sharp rise (quadratic, P less than .001) in plasma Tyr occurred at .73% dietary TAAA. Plasma lysine decreased (linear, P less than .001) to a low level at .76% TAAA, but plasma methionine was unaffected by treatment. Urine allantoin/urea X protein intake was maximized at .61% TAAA (quadratic, P less than .01). Nitrogen (N) intake varied among diets (quadratic, P less than .05), but fecal N was not altered by TAAA level.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
45.
In order to limit the number and impact of exotic pest invasions, leading-edge technologies must be embraced and embedded within integrated national and international biosecurity systems. Outlined here are recent advances in the detection of exotic pests, and prospects for the early recognition of disease. Applications of new tools are described, using our understanding of the genomes of pathogens and vectors. In addition, the role of mathematical and simulation models to aid both biosecurity planning, and decision making in the face of an epidemic, are discussed, and recent attempts to unify epidemiology and evolutionary dynamics are outlined. Given the importance of emerging diseases and zoonoses, the need to align human and veterinary surveillance within fully integrated systems is underlined.  相似文献   
46.
Abstract

AIMS: To ascertain the levels of awareness of legislation governing the welfare of cats, and provision of basic care, including vaccination, by cat-owners within two locations in New Zealand. To assess the ability of respondents to differentiate between the terms ‘stray’ and ‘feral’.

METHODS: A face-to-face questionnaire, consisting of 12 questions in three sections, was distributed by volunteers within Auckland (n=255) and Kaitaia (n=99) to gather information pertinent to the study's aims. Section 1 covered respondents’ personal details; Section 2, ownership and care of cats, including whether or not the cats were vaccinated against feline immunodeficiency virus (FIV) and feline leukaemia virus (FeLV); and Section 3, awareness of legislation and differences between the terms ‘stray’ and ‘feral’.

RESULTS: Overall, fewer than half of respondents were aware of the animal welfare legislation within New Zealand or the semantic differences between the terms ‘stray’ and ‘feral’ as they appear in the dictionary. Respondents ≥41 years old, and individuals employed in the animal-related sector, were significantly more likely to be aware of the legislation and make the correct distinction between the terms compared with those aged ≤40, and those working in a non-animal-related profession.

A significantly greater percentage of cat-owners (42%) provided care for cats they did not own compared with non-owners (26%). Results also indicated a large majority of cat-owners may consider standard annual vaccinations to include vaccination against FIV and FeLV.

CONCLUSION: Dissemination of information about animal welfare legislation is important for the care of cats within New Zealand, and the definitions of the terms ‘stray’ and ‘feral’ need to be more clearly stated in order to prevent confusion. This is especially important when cats may be controlled using lethal measures under different legislative precedents that are not necessarily consistent with one another.

CLINICAL RELEVANCE: Veterinary clinics may act as a primary source for the dissemination of information about relevant welfare acts as well as preventative health care, thus improving the welfare of cats. Cat-owners need to be better educated about the diseases covered by annual vaccination.  相似文献   
47.
48.
Karl Abetz     
Ohne Zusammenfassung  相似文献   
49.
SUMMARY Three groups of 8, 4-month-old male Jersey or Jersey-cross calves were infected with 2400 Dictyocaulus viviparus L3 larvae and either left untreated or injected subcutaneously with 200 μg/kg doramectin 5 or 25 days after infection (DAI). Lungworms were found in all untreated cattle (geometric mean = 49) at necropsy 39 or 40 DAI. None was found in any of the treated cattle. In a second experiment, groups of 6, 8-month-old calves were untreated or injected with 200 μg/kg doramectin 28, 21 or 14 days before each calf was challenged with 2700 D viviparus larvae. Lungworms were recovered at necropsy 32 to 34 DAI. The geometric mean worm burden in the untreated cattle was 550. This was reduced by 100%, 99.5% and 94.1% in calves treated with doramectin 14, 21 or 28 days, respectively, before infection. It was concluded that doramectin is a highly effective anthelmintic against D viviparus adult or L4 infections of cattle, and that reinfection of treated cattle will be significantly reduced for at least 28 days after treatment.  相似文献   
50.
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