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251.
252.
Efficiency of inspection procedures for the detection of tuberculous lesions in cattle 总被引:2,自引:0,他引:2
LA CORNER L. MELVILLE† K. McCUBBIN‡ KJ SMALL† BS McCORMICK§ PR WOOD JS ROTHEL 《Australian veterinary journal》1990,67(11):389-392
The sensitivity of the abattoir inspection procedure introduced for Australian export beef in 1976 was compared to a detailed necropsy procedure for the detection of tuberculous lesions in cattle. In a sample of cattle that were reactors to the tuberculin test, abattoir inspection failed to detect an estimated 47% of cattle with lesions. The detailed necropsy examination of cattle with lesions of tuberculosis identified 21 sites of infection compared with 13 to 18 in cattle examined by routine meat inspection procedures. Of the lesions detected during detailed necropsy, 15.9% did not involve the thoracic cavity or the medial retropharyngeal lymph nodes. The failure to detect lesions during abattoir inspection has its greatest significance in an animal with a single lesion. If the 245 cattle found with single lesions during detailed necropsy had been examined by abattoir inspection using the 1976 or the 1986 procedures, 0.8 and 8.9%, respectively, of these animals would not have been detected because the diseased tissues would not have been examined. If meat inspection is to provide an effective means of monitoring the level of bovine tuberculosis during the final stages of eradication, a procedure no less sensitive than that introduced in 1976 should be used. 相似文献
253.
254.
In this work, the influence of the donor male on the fertility of cryopreserved rabbit sperm after artificial insemination into females from different genotypes was evaluated. Females belonged to three lines selected for maternal characteristics (A, V and H) and all the possible crosses between them. Sperm from five males from the line selected for one of the maternal characteristics (line V) was frozen individually in a Tris-citric acid-glucose diluent with 1.75 m of DMSO and 0.05 m of sucrose (final concentrations). After artificial insemination of the cryopreserved sperm, fertility rates and prolificacy were similar for all groups of females (56% of fertility rate and 7.2 total born). Significant differences between males were observed for both fertility (p < 0.05) and kindling (p < 0.01) rate. These differences could be because of differences in the freezing resistance of sperm from the different males. 相似文献
255.
M Rodriguez F Marco-Jiménez JS Vicente MP Viudes-de-Castro 《Reproduction in domestic animals》2006,41(S2):105-105
In extensive systems, beef cows should be continuously with their calves to optimise pasture use but this practice can lengthen post-partum interval (PPI). A study was conducted to determine the influence of suckling frequency on Parda de Montaña cow-calf performance when cows are fed 70% energy requirements during lactation (outdoor winter conditions simulation). Thirty-six autumn-calving cows with similar body condition at calving (2.57) were assigned to three suckling systems [ ad libitum (AL), twice (2D) or once daily (1D) for 30 min]. Blood samples were collected twice a week to analyse progesterone concentrations by RIA. Cows lost similar weight until start of mating period (day 52 post-partum; −0.583, –0.513, –0.520 kg/day in AL, 2D and 1D). Standard milk yield was higher in AL than the rest (8.9, 6.2, 7.0 kg; p < 0.05), which was reflected on greater calf gain (0.895, 0.752, 0.676 kg/day; p < 0.05) and larger cow weight loss within 90 days post-partum in this treatment (–0.345, –0.188, –0.083 kg/day; p < 0.05). Suckling system did not affect either PPI (69.6, 89.1, 65.5 days) or cows cycling within 90 days post-partum (55, 46, 58%), which may compromise the target calving interval. In Parda de Montaña breed fed moderately pre-calving and undernourished during lactation, restricted suckling did not favour ovarian activity resumption, but post-partum subnutrition delayed about 40 days PPI observed in similar body condition at calving and calf management (Sanz et al., 2003; Anim Reprod Sci 79: 57–69) 相似文献
256.
Feline Bowenoid in situ carcinoma (BISC) is a rare disease that presents as multiple discrete plaques of epidermal hyperplasia and dysplasia. Two studies using immunohistochemistry revealed papillomaviral antigens in 11% and 47% of BISCs. Additionally, a recent study detected papillomaviral DNA in 24% of BISC lesions. To further investigate the association between papillomaviruses and BISC, polymerase chain reaction using consensus primers was used to detect papillomaviral DNA in 18 formalin-fixed samples of BISC. Papillomaviral DNA was amplified from 11 of the samples but from none of the controls. Six amplicons were sequenced; one was homologous with a papillomavirus from a human patient with multiple cutaneous squamous cell carcinomas and the other five showed weak homology to human papillomavirus type 17. These five sequences were > 96% homologous over a 235 bp sequence, indicating the presence in all five BISCs of one papillomavirus type distinct from any previously sequenced and more closely related to human than animal papillomaviruses. The results confirm an association between BISC and papillomaviruses, and as all six papillomavirus sequences identified are closely related to human papillomaviruses, it is possible that the virus is transmitted from humans to cats or vice versa. 相似文献
257.
Ontogeny of immune system organs in northern bluefin tuna (Thunnus orientalis, Temminck and Schlegel 1844) 总被引:4,自引:0,他引:4
Serial sections, prepared from 0.5 to 30 days posthatch (dph) larval and juvenile Thunnus orientalis (Temminck & Schlegel 1844), were stained with haematoxylin and eosin and examined by light microscopy for immune organ development. The early kidney was present at 0.5 dph, undifferentiated stem cells began to appear at 2 dph, and by 7 dph occasional small lymphocytes were present. The thymus was first obvious at 5 dph, located above the fourth branchial arch, small lymphocytes appeared at 7 dph, and by 15 dph an outer thymocytic zone and an inner epithelioid zone were visible. The progenitor spleen was present at 2 dph, located close to the gut, and by 12 dph it consisted of a mass of sinusoids filled with red blood cells, and remained mainly erythroid throughout the period studied. These results suggest that development of immune organs in this species is precocious relative to other marine teleosts. 相似文献
258.
The effect of anti- Paramoeba antibodies produced in sheep on Paramoeba sp., the causative agent of amoebic gill disease (AGD), was tested. Incubation of Paramoeba sp. with antiserum at a concentration of 20% or more effectively coated the Paramoeba with antibodies. The antiserum had no effect on Paramoeba sp. survival in vitro or on its ability to cause AGD in Atlantic salmon. 相似文献
259.
Confirmed congenital sarcocystosis has been reported extremely rarely in domestic ruminants. Sarcocystosis was diagnosed in a stillborn lamb with microscopic lesions predominantly in the central nervous system and placenta. Encephalitis was characterized by multiple foci of glial nodules some with central necrosis, perivascular cuffing and vascular occlusion, while placental lesions consisted of multifocal necroses, inflammation and mild calcification. Immature and mature schizonts were found in vascular endothelium of several organs. It is suggested that the protozoa were Sarcocystis tenella based on their morphology, location and as this is the most pathogenic Sarcocystis sp. parasitizing sheep. 相似文献
260.