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41.
42.
Thirty blood samples were collected randomly from each of the 38 breeder-broiler farms in Jordan. Serum samples were examined using indirect ELISA for specific antibodies to avian influenza virus. The overall true flock-level sero-prevalence of avian influenza was 71% (95% CI: 55,83). Positive flocks had 2-30 sero-positive chickens and half of flocks had >20 sero-positive birds. The number of sero-positive flocks varied in the studied localities with more sero-positives in farms located within the migratory route of migratory wild fowl. The examined broiler-breeder flocks had no clinical signs, or noticeable decrease in egg production; mortalities were within the normal range (0.1-1%). The number of positive sera/flock correlated with flock size. There were a no significant (Pearsons r=0.21, p=0.21) correlation between positive flocks and age. A non-pathogenic AI virus infects broiler-breeder farms in Jordan. Wild local and migrating birds might promote the further spread of this virus in Jordan and other countries.  相似文献   
43.
在欧洲,产品香辣宝6930(含3种植物提取物的有效成分:香芹酚、肉桂醛和辣椒素)作为抗生素促生长剂替代物在饲料中添加应用研究已经超过10年。然而,有关该产品在中国商业生产条件下的应用效果还未有过正式报道。本试验在同一栋畜舍内分2个批次进鸡重复相同的对比试验,试验分对照组和试验组,试验组是将对照日粮能量浓度降低25kcal/kg后,额外添加香辣宝6930100g/t到饲料中,观察其对肉鸡生产性能和成活率的影响效果。结果表明,在最初的2—4周,香辣宝对肉鸡体重增长有促进作用但尚未达到统计学的显著水平,但2个批次试验的料重比均减少2%以上;但试验最后2周和全期统计结果的增重和料重比与对照相比均有显著提高(3.5%,P0.05);从2个批次不同健康状态试验鸡的比较来看,香辣宝6930对健康状态稍差的鸡的成活率改善状况与对照相比更加明显(6.73%,P0.05)。  相似文献   
44.
Toxoplasmosis, caused by Toxoplasma gondii, is a significant disease in livestock and humans. In Iran, studies shows that T. gondii infection in humans is relatively high and prevalence is associated mainly with consumption of undercooked meat or meat products. We have examined 450 serum samples from female cattle distributed over all Ahvaz, the center of Khouzestan province, south-west of Iran. IgG antibodies to T. gondii were assayed by the modified agglutination test using whole tachyzoites of T. gondii, and found in 71 (15.77%) of 450 cattle with titers of 1:25 in 38, 1:50 in 18, 1:100 in 11, 1:200 in three and 1:400 in one. Titers of antibodies were decreased in cattle over 2 years old. These results indicate that T. gondii infection in cattle of Khouzestan is relatively considerable, but not very high and consumption of beef may be a source of infection for humans in south-west of Iran.  相似文献   
45.
In the present study, the relationship of normal adrenal dimensions with weight, aortic diameter, age and sex was evaluated. Moreover, a formula for estimating the normal dimensions of adrenal gland was provided. Thirty‐two intact adult dogs that were considered healthy based on history, physical examination, routine blood works and specific adrenal tests as well as absence of any abnormal ultrasonographic findings were included. Adrenal glands and abdominal aorta were imaged in the sagittal plane by ultrasound. Length, maximal height of the cranial and caudal poles, area and circumference of the left and right adrenal glands and also the internal diameter of the abdominal aorta were measured. Analysis showed that there is a positive correlation between the adrenal gland dimensions and weight and aortic diameter. The ratio of adrenal gland dimensions and the aortic diameter was calculated, but this ratio showed a great amount of variability in tandem with a significant correlation to the weight; Meaning that the ratio of the adrenal gland dimensions to the aortic diameter was not a reliable index for evaluating the size of the normal adrenal gland in animals with different weights. Therefore, we used the weight along with adrenal measurements in a linear regression model, and then, we were able to estimate the adrenal gland dimensions in different weights. Knowing the relationship of normal adrenal dimensions with the indices such as weight, age, sex and diameter of abdominal aorta can help the clinicians to diagnose the adrenal gland diseases.  相似文献   
46.
Tropical Animal Health and Production - Assessment of the ruminant livestock feed sources availability, existing feeding practices, and nutrient balances was embarked at different zones of Gurez...  相似文献   
47.
One hundred and three milk samples were collected from 52 cows, 21 ewes, 18 goats and 12 camels. The animals tested positive to at least one of the following: (1) standard tube agglutination test (SAT); (2) Rose Bengal plate test (RBPT); (3) milk ring test (MRT). All milk samples were examined by culture and single-step polymerase chain reaction (PCR) techniques for detection of Brucella species. The PCR assay amplified Brucella-DNA from 29 bovine milk samples, 10 from sheep, 13 from goats and one from a camel. The direct culture method detected Brucella organisms from 24 samples of cows' milk, 12 from sheep, 10 from goats and failed to detect any Brucella organisms from camels' milk. PCR detected up to 100 colony forming units (CFU) of B. abortus per millilitre of milk in 100% of diluted milk samples, and 1000 CFU of B. melitensis from 70% of milk samples. Although the overall sensitivity of the PCR was higher than the culture method, it should be possible to increase the sensitivity to detect lower numbers of Brucella organisms in field samples. The speed and sensitivity of the PCR assay suggest that this technique could be useful for detection of Brucella organisms in bovine milk, as well as in sheep, goat, and camels milk.  相似文献   
48.
Renal effects of the selective alpha(2)-adrenoceptor agonist, medetomidine, were investigated in anesthetized dogs. Animals were administered medetomidine 20 and 40 microg/kg intravenously (IV) and 80 mug/kg intramuscularly (IM) or 1 ml of saline IV. Urine and blood samples were collected before and at 30, 60, 90 and 120 min following medetomidine injection. Mean arterial blood pressure (MABP), renal blood flow (RBF), glomerular filtration rate (GFR), urine volume (U(v)), urine osmolality (U(osm)), free water clearance (C(H2O)), fractional clearance of sodium (F(Na)), plasma osmolality (P(osm)), plasma glucose levels and plasma antidiuretic hormone (ADH) concentrations were measured. The results showed that IV administration of medetomidine initially increased MABP 5-15 min followed by long-lasting decrease. The initial hypertension was not observed after IM administration, which was accompanied by a more profound hypotensive effects. RBF, GFR, U(v), C(H2O) increased after IV injection and decreased after IM. Medetomidine increased FNa and Posm and decreased U(osm). Plasma glucose levels initially increased and subsequently decreased. Plasma ADH concentration was decreased by IV injection but increased by IM administration. Our data imply that: 1) IV administration of medetomidine at dose rates of 20 and 40 microg/kg results in profound diuresis up to 2 hr; 2) Suppression of ADH release from the CNS is one of the mechanisms of medetomidine-induced diuresis although it may not be the principal one.  相似文献   
49.
Imprinted genes display biased expression of paternal and maternal alleles in mammals. They are marked through epigenetic process during gametogenesis. Characterization of imprinted genes has expanded our understanding of the regulation and function of genes. In the current study, 22 experimentally validated imprinted genes in bovine (Bos Taurus) were analysed. Several supervised machine learning algorithms and attribute weighting methods were used to find characteristics of different types of imprinted genes and suggest a classification method for finding maternally and paternally expressed genes in bovine. For assessing the best model and comparing attributes in other organisms, we have also conducted a comparative analysis for human and sheep imprinted genes. According to the results of the present study, GC contents 10 and 100 kb upstream, Gly and Gln amino acids, Ile/ATC codon usage, LINE and SINE in 100kbup and length of first intron were significantly different between the maternal and paternal genes in cattle. Considering all species together, we found that GC content 100 kb up, LINE 100 kb up and the frequency of amino acids like Gly, Gln and Met were the most important attributes for identifying the paternal and maternal imprinted genes. These findings could imply conservation pattern in the attributes among these species.  相似文献   
50.
In the present study, 1,635 lambing records of Ghezel (n?=?766) and Mehraban (n?=?869) breeds were used to evaluate the early growth traits, litter size, and lamb survival in sheep reared in Fars Province, southern Iran, during a 5-year-long period. The least squares means (± SE) of lamb birth weight for Ghezel were 5.27 (±0.22), 5.02 (±0.22), and 3.98 (±0.23) kg for single males, single females, and twin lambs, respectively; whereas, the corresponding values for Mehraban were 4.39 (±0.18), 4.18 (±0.18), and 3.50 (±0.19) kg. The least squares means of pre-weaning lamb growth (gram per day) for Ghezel were 239 (±15), 218 (±15), and 181 (±16) for single males, single females, and twin lambs, respectively, and the corresponding values for Mehraban were 204 (±12), 187 (±12), and 156 (±13). Lambs from 2 year old ewes or younger were on average lighter at birth and at weaning and had a lower average daily gain than those from older ewes (P?<?0.05). The percentage of twin births increased from 1.1 and 1.3 % for ewes aged ≤ 2 years to 19 and 12 % for those aged ≥ 6 years old in Ghezel and Mehraban, respectively (P?<?0.05). The mean pre-weaning lamb mortality was 7.1 and 4.1 % for Ghezel and Mehraban, respectively.  相似文献   
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