Marsupials in the lab     

Morton JF 《Science (New York, N.Y.)》1978,202(4369):696-697

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Marshland ecology     

Niering WA 《Science (New York, N.Y.)》1978,202(4374):1276-1277

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The ocean-atmosphere system     

Winchester JW 《Science (New York, N.Y.)》1978,202(4373):1179-1180

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Evaluation of reconstitution of immunodeficient mice by partially purified thymic extracts.     

G A Splitter  T C McGuire  W C Davis 《American journal of veterinary research》1978,39(4):659-663

Partially purified thymus products were used to evaluate the maturation of T lymphocytes in immunodeficient mice. Three different bovine thymic extracts, designated thymic extracts A, B, and C, were successful in increasing the longevity of conventionally raised nude mice. Daily injection of bovine thymic extracts A, B, and C and mouse thymus extracts failed to mature a population of T lymphocytes and restore the capacity to reject heart allografts. Preincubation of normal syngeneic bone marrow with thymic extract B in vitro before injection into nude mice also failed to reconstitute the host's ability to reject heart grafts. The number of antibody plaque-forming cells of sheep red blood cells in lethally irradiated, bone marrow-reconstituted mice could be increased by preincubating the bone marrow cells with bovine thymic extract fraction B before injection followed by daily injections. A similar but less marked increase in plaque-forming cells was obtained by the daily injection of bovine thymic extract fraction C. Complete functional maturation of T lymphocytes in immunodeficient animals appears to require more than thymic extract stimulation of bone marrow cells or pre-T lymphocytes.  相似文献   

PERINATAL FOAL MORTALITY ASSOCIATED WITH A HERPESVIRUS     

R. J. Dixon  W. J. Hartley  D. R. Hutchins  E. E. Lepherd  Caroline  Feilen †  R. F. Jones  †  Daria N.  Love †  Margaret  Sabine † Anne L.  Wells † 《Australian veterinary journal》1978,54(3):103-105

An outbreak of perinatal foal mortality associated with a herpesvirus is described. Twenty two foals either were still-born, or died soon after birth, or were weak and soon developed severe respiratory signs, or were normal at birth and developed respiratory symptoms 18 to 24 hours later. Elevated temperatures, heart and respiratory rates were constant features. The animals were severely leucopaenic, and showed an absolute neutropaenia. At autopsy the lungs were enlarged, and showed varying degrees of aeration and moderate to severe oedema and congestion. Histopathology showed an acute focal necrotising bronchiolitis with the presence of intranuclear eosinophilic inclusion bodies. Herpesvirus was recovered from 9 foals in cell culture and identified by electron microscopy.  相似文献   

BOVINE HERPESVIRUS 1 - INFECTION OF THE UPPER ALIMENTARY TRACT OF CATTLE AND ITS ASSOCIATION WITH A SEVERE MORTALITY     

R. J. Rogers  S. G. Knott  †  F. W. Eaves  R. C. Clague  ‡ 《Australian veterinary journal》1978,54(12):562-565

SUMMARY A severe cattle mortality in which 132 out of 340 animals died on a property in southern Queensland was investigated. Clinical signs shown by affected animals included fever, inappetance, depression, lethargy, salivation, diarrhoea, ataxia, and ulceration of the oral cavity. The most common lesions seen at autopsy of 6 affected animals were ulceration of the tongue, gums, dental pad and buccal mucosa, linear ulceration of the caudal third of the oesophagus, mild catarrhal enteritis and necrosis of lymph nodes draining areas of ulceration. Bovine herpesvirus type 1 (BHV 1) was isolated from 3 out of 5 animals from which virus isolation was attempted. BHV 1 was recovered from oesophageal ulcers, retropharyngeal lymph nodes, blood clot, and swabs from ulcers in the oral cavity but not from spleen, liver or mesenteric lymph node. Serum neutralising (SN) antibody to BHV 1 was detected in 4 out of 12 affected animals in the second of paired serum samples but not in the first. Mucosal Disease (MD) virus was not recovered from any of 17 animals from which isolation was attempted but moderate MD SN titres, without a rise on paired sera, were detected in affected animals. Fever, depression, inappetance, ulceration of the upper alimentary tract, and adrenal necrosis were produced in 2 susceptible animals following inoculation with third passage cell culture fluid containing BHV 1. A serological response to BHV 1, but not to MD virus was detected in one of the cattle infected experimentally.  相似文献   

CONGENITAL AND DEVELOPMENTAL ANOMALIES OF THE GENITALIA OF SLAUGHTERED BULLS     

P. J. Saunders  P. W. Ladds 《Australian veterinary journal》1978,54(1):10-13

The genital tracts of 968 slaughtered bulls (46% of which were young post-puberal animals) were examined for defects of a congenital or developmental nature. The overall occurrence of such lesions was 7%. These comprised persistent penile frenulum (0.5%), hypospadias (0.3%), detached urethral process (0.4%), testicular hypoplasia (0.2%), cryptorchidism (0.6%), mesonephric duct abnormalities (1.1%) and bulbourethral cysts, fusion and aplasia (3.6%). Segmental aplasia of the mesonephric duct, not previously recorded in the study area, was found in 4 Shorthorn bulls (0.4%); 2 affected animals were from one herd. In 3 cases of hypospadias (2 from one herd), the urethra communicated with the ventral surface of the penis at the junction of the body and glans through a slit-like orifice. The occurrence of defects observed was generally comparable to that found in bull populations elsewhere but elevated occurrence of several defects in particular herds emphasized the need for further study.  相似文献   

Inflammatory response of the bovine mammary gland to an irritant in the streak canal.     

W D Schultze  P D Thompson  S A Bright 《American journal of veterinary research》1978,39(5):785-790

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The quantitative composition of the gastrointestinal flora in piglets during the first weeks of life. 1. The development of the gastrointestinal flora in naturally reared piglets]     

F Schulze 《Archiv fuer experimentelle veterinaermedizin》1978,32(1):155-170

Studies were conducted into the quantitative composition of the gastro-intestinal flora of 30 naturally raised piglets in four age groups. The gastro-intestinal tract was found to be "flooded" by Escherichia coli, Clostridium perfringens, micrococci, streptococci, proteus, and lactobacteria over the first hours after birth. Development of the intestinal flora was complete at the age of four days. The groups of germs recordable from naturally and artificially raised piglets were, basically, the same. Piglets, consequently, have no specific "lactoflora".  相似文献   

Maternal immunity to infectious bovine rhinotracheitis and bovine viral diarrhea viruses: duration and effect on vaccination in young calves.     

J S Brar  D W Johnson  C C Muscoplat  R E Shope  J C Meiske 《American journal of veterinary research》1978,39(2):241-244

The immune response to modified live-virus bovine viral diarrhea (BVD) vaccine and infectious bovine rhinotracheitis (IBR) vaccine was examined in calves that had received passive maternal antibodies to these viruses. Blood serum samples from vaccinated and control (nonvaccinated) calves were examined for more than 1 year to determine the rate of decline of passive anti-BVD and anti-IBR antibodies and the effect that vaccination had on these antibody titers. The control calves lost their antibodies to BVD and IBR viruses at the rate of one half their remaining antibody titer every 21 days. Calves serologically responded to BVD vaccine at a time when maternal antibody titers remained between 1:96 and 1:20. However, animals did not seroconvert to the IBR vaccine until maternal antibodies had decreased and become undetectable. Evidence is presented to show that although passive immunity will inhibit IBR vaccination, priming for a secondary response will occur so that on subsequent vaccination, at a time when maternal antibodies have disappeared, the animals will respond anamnestically to IBR vaccination.  相似文献