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121.
122.
The morphology of Onchocerca lupi, responsible for canine ocular onchocercosis, is unique within the genus. Earlier analyses of the 5S ribosomal RNA gene spacer region sequence of the parasite and the 16S ribosomal RNA gene sequence of its Wolbachia endosymbiotic bacteria (Rickettsiales) supported the morphological and biological arguments that O. lupi is a distinct species. However, the exact phylogenetic position of O. lupi and its endosymbiont could not be unambiguously determined. Herein we report analyses based on the mitochondrial cytochrome oxidase I (COI) gene of the filarial species and the Wolbachia surface protein (wsp) and the bacterial cell-cycle ftsZ genes of their wolbachiae. Our results indicate that O. lupi separated from other Onchocerca spp. early in evolution. This is in line with the previous morphological analysis demonstrating that O. lupi is an atypical Onchocerca species showing both primitive and evolved characters. The phylogenetic trees generated for the COI sequences of filariae and the wsp and ftsZ sequences of their wolbachiae were congruent with each other, which supports the hypothesis that nematodes and their Wolbachia endobacteria share a long co-evolutionary history. 相似文献
123.
The literature mostly indicates that docking fat-tailed lambs initially reduces growth but that post-weaning growth and feed
conversion efficiency then increase. The amount of fat deposited, the total separable lean meat to fat ratio and the meat
quality all increase, while the percentage of bone in the carcase either decreases or does not change in the carcases of the
docked lambs. Wool growth and characteristics are, in general, not affected and reproductive traits in ewes and lambs are
improved by docking. The rectal temperature, respiration rate and pulse rate are decreased following docking. The concentrations
of immunoreactive beta-endorphin and cortisol in the plasma and the incidence of foot stamping and restlessness, as indicators
of stress, increase after docking. Other constituents of the blood are not significantly altered following docking or by the
methods of docking. Docking of fat-tailed sheep using rubber rings at one day of age can be recommended.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
124.
Tissue samples taken from the mammary gland of 42 dogs (age: 6 to 12 years) were examined. Thirty-eight samples showed neoplasia: 36 were epithelial while the remaining 2 proved to be connective tissue tumours. Thirty-four % of the neoplasms were new benign tumours (most frequently adenoma and fibroadenoma) and 66% were malignant ones (mainly adenocarcinoma). The oestrogen receptor (ER) and progesterone receptor (PR) binding capacity was determined on 21 tissue samples using the method of EORTC (1980). The connective tissue tumours and non-tumourous tissues contained no sexual steroid receptor. 71.4% of all tissue samples contained receptors. 61.9% of the samples was ER+, 42.8% was PR+, 33.3% contained both receptors, 28.6% was only ER+ and 9.5% only PR+. The average ER and PR binding capacity was 120.3 (5.0-622.8) and 266.7 (92.3-475.0) fmol/mg cytosol protein, respectively. No difference in receptor positivity was demonstrable between the benign and the malignant tumours. PR negativity accompanied by ER positivity was more common in the case of benign tumours. ER binding capacity tended to be correlated with age: this correlation could be described with a hyperboloid regression curve (r = -0.5931; 0.06 > p > 0.05). 相似文献
125.
126.
Unsuccessful attempts to transmit scrapie by nematode parasites 总被引:2,自引:0,他引:2
127.
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130.
Alawa Clement B. I. Etukudo-Joseph I. Alawa Judith N. 《Tropical animal health and production》2011,43(1):127-131
A 6-year retrospective study (2000–2005) of animals slaughtered at the Zango abattoir in Zaria, Kaduna State, Nigeria was
carried out to determine disease conditions encountered in slaughtered animals. Records kept at the abattoir were analysed.
A total of 69,307 cattle, 3,820 goats and 1,763 sheep were slaughtered for the period under study. Of the 69,307 cattle slaughtered
for the period, 22,459 (32.41%) were males and 46,848 (67.59%) were females, while 1,763 sheep were slaughtered comprising
of 506 (28.70%) males and 1,257 (71.30%) females, and 3,820 goats made up of 1,212 (31.73%) males and 2,608 (68.27%) were
females. The major disease and/or pathological conditions were helminthosis (fascioliasis, haemonchosis and paramphistomosis)
16.20%, Streptothricosis 4.15%, Pericarditis 2.20%, liver cirrhosis 2.08%, abscesses 1.04%, pneumonia 0.14%, nephritis 0.05%
and Contagious Bovine Pleuropneumonia, Tuberculosis and Nocardiosis 0.01% each. Out of the 15,075 infected organs, 13,314
(88.38%) were partially salvaged while 1,751 (11.6%) whole organs were condemned. A total of 1,239 pregnant cows, 221 pregnant
ewes and 637 pregnant does were slaughtered, representing a foetal wastage of 2.65% for cattle, 17.58% for sheep and 24.43%
for goats. The result of this study apart from serving as an indicator of field disease condition also demonstrates cases
of serious losses in production due to slaughter of pregnant animals especially for sheep and goats. 相似文献