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31.
This study evaluated the presence of Neospora caninum in ovarian follicle aspirates and uterine flushes obtained from N. caninum seropositive dairy cows. Ninety-two cows that aborted within the previous 90 days were sampled to determine the presence of antibodies against N. caninum. Thirteen seropositive cows were chosen for collection of blood leukocytes, uterine flushes (UF; n=12) and follicular aspirates (OPU; n=13). Samples were centrifuged and the cellular sediment from the follicular fluid, uterine flushes and blood leukocytes were used for DNA extraction and PCR. Follicular aspirates had the highest frequency of DNA amplification for N. caninum (p<0.05, 92.3%; 12/13). Whereas uterine (4/12) and blood leukocyte (5/13) samples had similar (p>0.05) rate of positive results. Nonetheless, there was no agreement between blood leukocytes and follicular samples taken from the same animal (Cohen Kappa=-0.16). Similarly, blood leukocytes and uterine results had moderate agreement between them (Cohen Kappa=0.47). This study indicates that N. caninum is present in the ovarian follicle and uterus of seropositive cows, suggesting a possible risk of neosporosis transmission between females during oocyte and embryo collection and transfer. Hence, precautions should be taken to minimize the risk of N. caninum transmission. Furthermore, the high incidence of positive results in follicle samples, that exceeded that of their paired blood leukocytes, suggests a possible tropism of N. caninum for the ovarian follicle.  相似文献   
32.
OBJECTIVE: To examine attitudes toward farm animal welfare among veterinary college faculty. DESIGN: E-mail survey. STUDY POPULATION: 157 US veterinary college faculty with large animal or food animal emphasis. PROCEDURE: Veterinarians from 27 US veterinary colleges were contacted via e-mail and asked to complete a 7-page survey relating to farm animal welfare issues. Thirty-one percent of those contacted responded. RESULTS: 71% of respondents self-characterized their attitude toward farm animal welfare as "we can use animals for the greater human good but have an obligation to provide for the majority of the animals' physiologic and behavioral needs." An additional 19% of respondents were more concerned about animal welfare than was indicated by that statement, and 10% were less concerned about farm animal welfare than was indicated by that statement. Significant relationships among demographic variables and attitude scores were observed, including more concerned attitudes among females, those with more liberal political views, and those who cited lower religiosity. No relationship between attitude and age was observed. CONCLUSIONS AND CLINICAL RELEVANCE: Veterinary college faculty have the opportunity to impact many stakeholders within the animal agriculture industries (eg, future veterinarians and policy makers looking for a veterinary science perspective). Results indicated that a considerable level of concern toward farm animal welfare is present in this population. Although the process of change may not be rapid, it is likely that the influence of these respondents will factor heavily into enhancing farm animal welfare.  相似文献   
33.
Two field trials were conducted in Brazil to evaluate LHRH immunocastration of Bos indicus bulls (d 0 = 2 yr of age). In Study I, 72 bulls were assigned randomly to one of three treatment groups: LHRH0-immunized, castrated, and intact. Immunized animals (n = 25) received a primary and two booster injections of ovalbumin-LHRH-7 and thioredoxin-LHRH-7 fusion proteins on d 0, 141, and 287. Twenty-three bulls were surgically castrated on d 141, and 24 served as intact controls. All animals were slaughtered on d 385, at approximately 3 yr of age. In Study II, 216 bulls were assigned randomly to the same three treatments as in Study I; however, because of a drought in the area, bulls were kept on pasture an additional year, and a fourth treatment was added, in which one-half the LHRH-immunized bulls received an additional booster on d 639 (fourth immunization). All animals in Study II were slaughtered on d 741 (4 yr of age). Luteinizing hormone-releasing hormone antibodies increased following each immunization for immunized bulls, but they were not detectable in castrate or intact animals in either study. Consequently, scrotal circumference was suppressed in immunized bulls compared with intact controls in both studies. By d 287, serum concentrations of testosterone in LHRH-immunized bulls were decreased compared with intact controls (P < 0.01). In both studies, testes and epididymal weights at slaughter were greater (P < 0.01) for intact (500 +/- 17 and 60 +/- 2 g, respectively) than for immunized bulls (173 +/- 22 and 26 +/- 2 g, respectively) and fourth immunization bulls (78 +/- 23 and 20 +/- 2 g, respectively; Study II). At the end of each study, BW was greater (P < 0.01) for intact bulls than for castrated and LHRH-immunized animals. In these two studies, the efficacy of the LHRH fusion proteins to induce an effect similar to that of surgical castration was considered 92 and 93%, respectively. These data support the concept that immunocastration of bulls at 2 yr of age was successful and that it has practical application as a tool for producing grass-fattened bulls in Brazil.  相似文献   
34.
Imazapyr owes its importance in Morocco to its success in controlling the perennial weed Solanumelaeagnifolium Cav., which infests the Tadla area. Persistence and mobility of imazapyr has been studied in two Moroccan soils from the Rabat area, with differing organic matter content (red and organic soils), under laboratory conditions at 75% of their field capacities and 25–28 °C. Residue analysis was performed on the basis of a bioassay test using lentil (Lens culinaris Medic.) as indicator species. The residual activity of imazapyr accounted for 69%, 25%, 50% and 62%, 46%, 66% of the initial activity for the red and organic soils at 1, 5 and 10 mg L?1 respectively. The half-lives varied between 25 and 58 days for the red soil and 55 and 58 days for the organic soil. In the organic soil, imazapyr was highly mobile under the irrigation regime applied. Most of the activity was found in the first 3 × 75 mL of the effluents. A following biotest with the leached soil showed low remaining residual activity.  相似文献   
35.
The data obtained from a survey of Mycobacterium bovis infection in wild red deer (Cervus elaphus) and wild boar (Sus scrofa) conducted in France in the 2005/06 hunting season were used to describe and quantify the pathological findings in the two species. The red deer had caseous abscessed lesions in their organs and lymph nodes, whereas in the wild boar the lesions were predominantly caseocalcareous and occurred mainly in the lymph nodes. The severity of the gross tuberculosis-like lesions was estimated on the basis of a numerical score. The significant difference between the distribution of the scores in the two species indicated that the disease was more serious in the red deer than in the wild boar. Unlike the red deer, the wild boar did not show a generalised pattern of disease. Among the lymph nodes examined systematically, gross lesions were most frequently observed in the mesenteric lymph nodes in the red deer and in the retropharyngeal lymph nodes in the wild boar. In both species, the presence of gross lesions showed the closest agreement with the isolation of M bovis from the same lymph nodes. The different patterns of the lesions of tuberculosis in the two species suggest that red deer might play an important role in the intraspecies and interspecies dissemination of the infection, whereas in wild boar the spread of the infection would be more likely to be restricted to other wild boar.  相似文献   
36.
Severe combined immunodeficiency disease (SCID) of horses is an autosomal, recessive hereditary disease occurring among Arabian or crossbred Arabian horses. The genetic defect responsible was previously identified as a 5‐base pair deletion in the gene encoding the catalytic subunit of the DNA dependant protein kinase (DNA‐PKcs). This study was carried out to determine the frequency of SCID and identify horses carrying the gene for SCID among Arabian and Arabian crossbred stallions and mares in Morocco using a DNA‐based test. Twenty‐one horses were SCID carriers: 14 (7%) Arabians, 6 (4%) Arab‐Barbs and one (3.3%) Anglo‐Arab. After analysing their genealogy, 3 imported stallions were identified that disseminated the mutant gene of DNA‐PKcs in Morocco.  相似文献   
37.
Mega‐environment (ME) identification is the first step for evaluating, selecting and recommending genotypes within a target region (TR). The present study aimed to (a) identify MEs, using GGE biplot methods, in Brazilian edaphoclimatic region (ECR) 402 of soybean cultivation, located in the Mato Grosso State (the TR) and (b) compare the performance of genotypes within the TR and in each ME using fixed and mixed models. Data from three years of soybean yield trials, 19 genotypes and 22 environments were used. The biplots GGE, GGL + GGE and GGS + GGE were implemented to identify the MEs. Two MEs were identified in the TR. ME1 presents a higher altitude, farms which use a higher level of fertilizer inputs and a higher occurrence of the soybean cyst nematode (SCN) than ME2. When selection and recommendation are made based on MEs, genotypes with both broadly and specific adaptation can be selected. This action can improve grain yield in the entire target region.  相似文献   
38.
Campylobacter species are a major cause of foodborne bacterial infections in both developed and developing countries worldwide. Campylobacter jejuni is responsible for the majority of infections. This study was conducted to identify virulenceassociated genes in Campylobacter species isolated from livestock production systems in South Africa. A total of 250 fecal samples consisting of cattle(n=50), chickens(n=50), goats(n=50), sheep(n=50) and pigs(n=50) were randomly collected from livestock in Eastern Cape and KwaZulu-Natal provinces of South Africa between April and October 2018. The samples were analyzed for the presence of virulence genes in Campylobacter species using molecular PCR-based methods. It was found that 77 and 23% of Campylobacter jejuni and Campylobacter coli respectively were isolated from all the livestock samples. There were positive significant(P0.05) correlations amongst all the virulence genes that were investigated. Chisquare and Fisher's exact tests were implemented to test for the effect of livestock species on the presence or absence of virulence genes. The study demonstrated that most of livestock species can potentially cause zoonotic infections and food poisoning due to the high prevalence of Campylobacter. The high prevalence of virulence genes highlights the significance of Campylobacter in livestock production systems in South Africa. This requires the implementation of one-health approaches to reduce the impact of foodborne and zoonotic diseases for the welfare of human and animal health.  相似文献   
39.
The present study was performed to evaluate the effect of vitamin C on the performance of Nile tilapia (Oreochromis niloticus) affected by the usage of engine oil. A total of 120 tilapia fish were randomly divided into four equal groups according to dietary treatments applied for 3 weeks: group I (control); group II was exposed to engine oil; group III was exposed to engine oil and supplemented with vitamin C: and group IV was fed only a diet supplemented with vitamin C. According to our results, the group exposed to engine oil (II) showed an induced elevation of kidney function parameters, an upregulation of CYP1A1 mRNA expression level, a reduction in antioxidant status (SOD, GSH) and severe abnormal histological and ultra‐structural changes in the head kidney, trunk kidney and muscle tissue. Supplementation of group III with vitamin C ameliorated the toxic effect induced by engine oil through improvement of kidney function parameters, elevation of the antioxidant status of tissue and improvement of the histological images of renal and muscle tissues. In conclusion, vitamin C has the ability to ameliorate engine oil oxidative stress toxicity in Nile tilapia.  相似文献   
40.
The liquid limits, degrees of dispersion, and moisture retention of a Tropical Red Earth consisting predominantly of kaolin and iron oxides were independent of the nature of the saturating cation. The same three properties of a Tropical Black Earth consisting predominantly of montmorillonite were dependent upon the nature of the saturating cation, with Na giving the highest values and K the lowest. Ca and Mg gave intermediate and essentially equal values. The effects of the four cations have generally been explained in terms of the balance between attractive and repulsive forces in soil solutions and pastes. Unexpected behaviour due to K saturation has been explained by specific adsorption of K in a manner similar to but weaker than irreversible fixation. Linear regression equations were derived to express the dependence of the three properties on the saturating cations. The regression equations, which were all highly significant, show that the four cations examined were acting independently. Small positive interactions between Na × K, Mg × K, and Ca × K indicated that the effect of K fixation was important only when the Black Earth was nearly saturated with K ions.  相似文献   
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