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271.
S. F. Bilgili 《British poultry science》1989,30(2):455-459
1. This article addresses the current and future role of artificial insemination (AI) in the broiler industry.
2. The application and success of AI programmes in commercial broiler breeder operations are largely dependent on efficient cage management (nutrition, lighting, environment, health programmes) of both males and females.
3. Artificial insemination will remain a viable alternative for the broiler industry, which competes within the economic constraints of least‐cost production. 相似文献
272.
F. Atroshi J. Parantainen S. Sankari T. Österman 《Veterinary research communications》1989,13(6):427-433
Cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) cocentrations in milk and plasma samples from healthy and mastitic cows were determined by radioi-immunoassay and compared with prostaglandins (PGE2, PGF2 and thromboxane B2 [TXB2]), phospholipids and other relevant parameters in milk and blood. The concentrations of cAMP were about five times higher in plasma (p<0.01) than in milk, whereas the cGMP concentration in milk was three times higher (p<0.01) than that in plasma in both healthy and diseased animals. In mastitic milk, the cAMP and cGMP concentrations were 19% and 65% and in blood plasma 13% and 84% higher respectively than in healthy animals. In milk, cyclic nucleotide concentrations correlated with the markedly elevated cell count and also with the prostaglandin concentration and pH. In blood, cAMP correlated positively with phospholipids and cGMP with reduced glutathione (GSH). These changes are considered to be important in the disease process and, in particular, the increase in cGMP deserves further study. 相似文献
273.
Organochlorine insecticide problems in livestock 总被引:1,自引:0,他引:1
M F Raisbeck J D Kendall G E Rottinghaus 《Veterinary Clinics of North America: Food Animal Practice》1989,5(2):391-410
1. Antidotal therapy for acute OC intoxications is symptomatic and supportive. Use sedatives to control convulsions and AC to adsorb any pesticide remaining in the gut, and wash topical exposures. 2. Published kinetics should be applied to field situations with caution. In general, residues decline relatively quickly immediately following the last exposure; thereafter, the rate slows considerably. The elimination-rate constant and, hence, the half-life of any given OC is dependent on many variables that usually are not known under field conditions. This fact may result in serious errors if literature values are relied on too heavily in predicting the outcome of "natural" contamination. As a rule of thumb, elimination data derived from animals experimentally fed to plateau concentrations may be regarded as fairly conservative for such purposes, if the contaminated animals are maintained in a normal fashion. Probably the least risky method of predicting return to marketability is using frequent samples, taken at regular intervals (for example, 1 to 2 weeks) during the first month after last exposure, to adjust literature values. 3. Residues from larger dosages and shorter exposures tend to be smaller in proportion to dose and are eliminated more quickly than those resulting from longer exposures and smaller doses. 4. Activated charcoal is of universal benefit only if given immediately after exposure. 5. Pharmaceutical modifiers of xenobiotic metabolism such as phenobarbital are of very limited value. The particular type and amount of residual OC and the potential economic benefit of therapy should be considered thoroughly before undertaking such therapy. In most cases, the expense won't be justified. 6. Mineral oil increases the fecal excretion of some OC. Fecal excretion, however, is so small in relation to total body burdens that even a several-fold increase may not be useful economically except when residue concentrations are low to start with. 7. Nutritional strategies have the advantage of being very cheap. Practitioners should remember, however, that tissue concentrations actually may increase as body fat decreases. The costs of maintaining animals for an extra 6 to 10 months should be considered before undertaking such an effort.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
274.
Blood platelets and bone marrow megakaryocytes from a dog with essential thrombocythemia were analyzed by transmission electron microscopy and compared with those of control dogs. Platelets varied in size and shape and contained enlarged and dilated open canalicular systems. Megakaryocytes were dysmorphic and had evidence of abnormal maturation, with large numbers of megakaryoblasts containing alpha granules and poorly organized and reduplicated demarcation membranes. The fewer, more mature megakaryocytes lacked normal cytoplasmic organization. Most notable was the absence of well-demarcated "platelet fields," due to the excessive and disorderly array of demarcation membranes. 相似文献
275.
F Madec C Kaiser J M Gourreau F Martinat-Botte 《Comparative immunology, microbiology and infectious diseases》1989,12(1-2):17-27
Pathological consequences of a severe outbreak of swine influenza (H1N1 virus) in the non immune sow at the beginning of pregnancy, under natural conditions. A sudden acute outbreak of fever, depression, anorexia and coughing in a group of nulliparous sows from a herd that was currently under epidemiological investigation lead to build a particular disposal of observation. The clinical signs were daily recorded including rectal temperature. Blood was taken from the sows at the beginning of the troubles and 3 weeks later for the detection of Aujesky's disease, coronavirus TGE-like, Influenza viruses A/H1N1 and A/H3N2 and Mycoplasma hyopneumoniae. Viral detection was attempted from nasal swabs and aborted fetuses during the acute phase. The clinical study showed fever reaching near 41 degrees C on most of the pigs and lasting usually from 2 to 5 days. The diagnosis of Influenza (virus swine H1N1) was established both on serology (massive seroconversion) and on the detection of the virus from the nasal swabs and from an aborted fetus. The control of the lungs of sows "not in pig" and culled showed extended lesions of bronchopneumonia and Pasteurella multocida was found. The technical consequences of this severe outbreak of Influenza on reproduction were mainly important at the beginning of pregnancy. Over 13 sows inseminated less than 1 week before the outbreak, only 3 farrowed (respectively 5.5 and 12 piglets); 7 returned to oestrus and 3 "not a pig" at 21 days (echotomography) did not show signs of heat and were culled. Over 8 pregnant sows (1 month of pregnancy), 6 farrowed normal litters and total embryonic resorption occurred in 2 sows. Over 18 pregnant sows (more than 45 days gestation) one aborted. 相似文献
276.
A Leoni A M Nieddu F Guarda M Castagnaro A Firinu P Cossu V Mingioni 《Schweizer Archiv für Tierheilkunde》1989,131(6):361-368
A severe neurological disorder was observed during a very dry season, in sheep pasturing on land with mediterranean vegetation. During the crisis, lasting 5-20", ataxia and convulsions were the main clinical signs. Brain congestion, spongy appearance of the liver, interstitial nephritis and hyperpigmentation of visceral lymph nodes were the most important macroscopic lesions. Histopathological, histochemical and ultrastructural findings confirmed liver and kidney lesions and showed considerable neurovisceral storage of lipofuscin. Although further toxicological and experimental studies are needed to elucidate the origin of the disease, the Authors attribute the outbreak of the neurological syndrome to the ingestion of a neurotoxin containing plant. 相似文献
277.
Gough JF 《The Canadian veterinary journal. La revue veterinaire canadienne》1989,30(8):672-674
Outbreaks of budgerigar fledgling disease (BFD) occurred in three budgerigar aviaries in Ontario. Acute death in seven to ten-day-old nestlings and feather abnormalities in birds over three weeks of age were common findings. Ascites, hepatomegaly and hydropericardium were prominent gross lesions. Histologically, basophilic intranuclear inclusions were seen in many tissues. A severe drop in hatchability occurred in one aviary—a finding not previously reported with BFD. Interruption of breeding controlled the disease in aviary 1, but failed in two consecutive attempts in aviary 2. A third outbreak occurred in aviary 2 after depopulation and restocking. In aviary 3, the spread of disease was very rapid; 90% of the nestlings died within a few weeks. A papovavirus similar to a previously described isolate was recovered in this outbreak. 相似文献
278.
The response of coffee (Coffea arabica L.) floral buds to different water deficits followed by re-irrigation was investigated. Flower opening was stimulated by irrigation after one period of water deficit if predawn leaf water potential declined below -0.8 MPa. Similar stimulation of flowering was observed when less severe but more prolonged water deficits (ca. -0.3 to -0.5 MPa for two weeks) were imposed, even if water deficit was relieved by re-irrigation several times during this period. Consistent results were obtained in the field and in two greenhouse locations. Stimulation of flower opening by water deficit followed by re-irrigation was restricted to buds at the "open white cluster" stage of development (Stage 4). Only buds at this stage exhibited development of secondary xylem. Split-root experiments indicated that a root signal stimulated flower opening, independently of predawn or midday leaf water status. Frequent irrigation to prevent flowering, followed by a controlled water deficit and re-irrigation to stimulate flowering, may represent a practical method to synchronize flowering and shorten the harvest period in leeward coffee production areas in Hawaii. 相似文献
279.
280.
Evaluation of postoperative complications following elective surgeries of dogs and cats at private practices using computer records. 总被引:2,自引:1,他引:1 下载免费PDF全文
F L Pollari B N Bonnett 《The Canadian veterinary journal. La revue veterinaire canadienne》1996,37(11):672-678
This study was designed to determine the frequency of postoperative complications following elective surgeries (castration, ovariohysterectomy, onychectomy) of dogs and cats from private practices and to evaluate the use of electronic medical records for this type of research. All elective surgeries performed during the study period at 5 private practices were included. The surgical techniques and materials used for each procedure were similar across practices, but the interpretation of "complication," the amount of detail recorded on the primary medical record, and the intensity of follow-up varied. The frequencies and types of complications varied by species and procedure. The postoperative complication frequencies ranged from 1% to 24% for all complications and 1% to 4% for severe complications. The results of this study describe populations of elective-surgery patients at private practices, provide data for educating clients about the risks associated with these procedures, and demonstrate how computerized records can be used to collect practice-specific medical information. 相似文献