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991.
An intra-abdominal testicular tumour was diagnosed in a 10-year-old, male, cryptorchid golden retriever. Upon surgical removal, torsion of the testis was found. The histopathological diagnosis was seminoma. The ultrasound examination in this case revealed a parenchymal mass lesion. An ultrasound examination is a useful supplemental diagnostic tool for differentiation of abdominal mass lesions.  相似文献   
992.
993.
Trace minerals feeding had significant effects on sperm production and fertility with better absorption and proper utilization within the body for optimum reproductive function. Several studies have shown that more influenced trace elements in the diets of animals are copper (Cu) and zinc (Zn). Bucks showing deficiency of this mineral might affect the quality of semen production which in turn would affect the fertility. This experiment was thus designed to test the effects of organic Cu and Zn supplementation on antioxidants enzyme activities and sperm functional attributes in fresh semen of bucks. Forty bucks (n = 40, Aged 5 months) were assigned to ten groups of four animals in each group, supplemented (for a period of 8 months) with different levels of organic Zn: 20 mg (T2), 40 mg (T3) and 60 mg (T4), organic Cu: 12.5 mg (T5), 25 mg (T6), 37.5 mg (T7) and combined organic Zn and Cu: 20 + 12.5 mg (T8), 40 + 25 mg (T9), 60 + 37.5 mg (T10), respectively, per kg dry matter and no additional mineral diet (control; T1). One hundred and sixty semen samples were collected through electro‐ejaculator and analysed for sperm quantity, quality, acrosome intactness and plasma membrane integrity and correlated with the catalase, superoxide dismutase, glutathione peroxidase and glutathione reductase enzyme activities in seminal plasma. The results indicated organic Cu and zinc supplemented bucks produced more sperm cells, had higher sperm concentrations, maintained higher (< .01) sperm livability, plasma membrane and acrosome integrities, more motility and velocity. The increased antioxidant enzyme activities, reduced oxidative stress and lowered lipid peroxidation were positively correlated (< .05) with the sperm functional attributes. In conclusion, organic Cu and Zn supplement to male goats showed protective roles against oxidative damage and maintained better fresh semen characteristics.  相似文献   
994.
Xanthomonas campestris pv. campestris (Xcc) is the causal agent of black rot in Brassicaceae. It is widespread in Italy and severe outbreaks occur under conditions that favour disease development. In this study a multilocus sequence typing approach (MLST) based on the partial sequence of seven loci was applied to a selection of strains representative of the main areas of cultivation and hosts. The aim was to investigate whether the long tradition of brassica crops in Italy has influenced the evolution of different Xcc populations. All loci were polymorphic; 14 allelic profiles were identified of which 13 were unique to Italian strains. Based on the seven loci, the most common genotype within the Italian Xcc strains (AP1) was also the most representative genotype found in worldwide Xcc strains. This genotype was included in a new clonal complex in addition to three other clonal complexes already identified in Xcc populations. The phylogenetic reconstruction using a concatenated dataset of four conserved protein-coding genes, dnaK, fuyA, gyrB and rpoD, showed that the Italian strains belonged to two genetic groups. Physiological races were also investigated for the first time in Italy. The race structure of Xcc was determined by inoculating eight differential Brassica lines belonging to five species and showed that, in Italy, race 4 is the most widespread, followed by races 1 and 6. No correlation was found between allelic profiles, host of isolation, geographical origin and races, although a prevalent race was identified within the same clonal complex.  相似文献   
995.
The effects of a hot water infusion and an aqueous acetone extract of green tea (Camellia sinensis) on the motility of infective larvae of the sheep nematodes Teladorsagia circumcincta and Trichostrongylus colubriformis were investigated under in vitro conditions. The infusion and extract dose-dependently inactivated the infective larvae as assessed by the larval migration inhibition (LMI) assay. To determine the components responsible for the inhibitory activity, the hot water infusion and aqueous acetone extract of green tea were fractionated on Sephadex LH-20 and the green tea extract fractions (GTE-I-VIII) characterised by mass spectrometry. The larvae were exposed to increasing concentrations of these GTE fractions. Fractions containing epigallocatechin gallate (EGCG) and proanthocyanidin oligomers were most effective. GTE fractions were more effective against T. circumcincta than T. colubriformis larvae as assessed by the LMI assay.  相似文献   
996.
Phoma black stem is an important disease in sunflower, against which no specific management method is currently deployed in France. Relevant phenotyping methods for quantitative resistance are critical for integration of this trait into breeding programmes. Components of resistance associated with physiological resistance, and morphological traits associated with disease escape were measured on 21 sunflower genotypes under growth chamber (on seedlings), greenhouse (on adult plants), and field conditions, together with disease intensity in the field. Potential predictors were first selected for sensitivity and robustness from mixed model anova s. Analyses involving ranking tests and logistic regressions were then performed to identify predictors for field resistance. The identification of predictors for resistance involved analyses conducted in two broad steps: process‐oriented experiments, and epidemic‐oriented experiments. This stepwise approach departs from many studies aimed at identifying predictors for field resistance, which rely mainly on the computation of correlation coefficients between predictors and measured field disease variables. Predictors for quantitative resistance were identified: (i) lesion length and lesion expansion on stems of plants before flowering stage, and (ii) lesion length on first leaf petioles of seedlings. A high number of leaves and tall plants were associated with disease escape. Control genotypes for susceptibility and quantitative resistance were identified, and implications for breeding and improvements were derived from this work.  相似文献   
997.
998.
Selamectin is a broad-spectrum avermectin endectocide for treatment and control of canine parasites. The objective of these studies was to evaluate the clinical safety of selamectin for topical use in dogs 6 weeks of age and older, including breeding animals, avermectin-sensitive Collies, and heartworm-positive animals. The margin of safety was evaluated in Beagles, which were 6 weeks old at study initiation. Reproductive, heartworm-positive, and oral safety studies were conducted in mature Beagles. Safety in Collies was evaluated in avermectin-sensitive, adult rough-coated Collies. Studies were designed to measure the safety of selamectin at the recommended dosage range of 6-12mgkg(-1) of body weight. Endpoints included clinical examinations, clinical pathology, gross and microscopic pathology, and reproductive indices. Selected variables in the margin of safety and reproductive safety studies were subjected to statistical analyses. Pups received large doses of selamectin at the beginning of the margin of safety study when they were 6 weeks of age and at their lowest body weight, yet displayed no clinical or pathologic evidence of toxicosis. Similarly, selamectin had no adverse effects on reproduction in adult male and female dogs. There were no adverse effects in avermectin-sensitive Collies or in heartworm-positive dogs. Oral administration of the topical formulation caused no adverse effects. Selamectin is safe for topical use on dogs at the recommended minimum dosage of 6mgkg(-1) (6-12mgkg(-1)) monthly starting at 6 weeks of age, and including dogs of reproducing age, avermectin-sensitive Collies, and heartworm-positive dogs.  相似文献   
999.
ABSTRACT Fusarium oxysporum f. sp. ciceris and the root-lesion nematode Pratylenchus thornei coinfect chickpeas in southern Spain. The influence of root infection by P. thornei on the reaction of Fusarium wilt-susceptible (CPS 1 and PV 61) and wilt-resistant (UC 27) chickpea cultivars to F. oxysporum f. sp. ciceris race 5 was investigated under controlled and field conditions. Severity of Fusarium wilt was not modified by coinfection of chickpeas by P. thornei and F. oxysporum f. sp. ciceris, in simultaneous or sequential inoculations with the pathogens. Root infection with five nematodes per cm(3) of soil and 5,000 chlamydospores per g of soil of the fungus resulted in significantly higher numbers of propagules of F. oxysporum f. sp. ciceris with the wilt-susceptible cultivar CPS 1, but not with the wilt-resistant one. However, infection with 10 nematodes per cm(3) of soil significantly increased root infection by F. oxysporum f. sp. ciceris in both cultivars, irrespective of fungal inoculum densities (250 to 2,000 chlamydospores per g of soil). Plant growth was significantly reduced by P. thornei infection on wilt-susceptible and wilt-resistant chickpeas in controlled and field conditions, except when shorter periods of incubation (45 days after inoculation) were used under controlled conditions. Severity of root necrosis was greater in wilt-susceptible and wilt-resistant cultivars when nematodes were present in the root, irrespective of length of incubation time (45 to 90 days), densities of nematodes (5 and 10 nematodes per cm(3) of soil), fungal inocula, and experimental conditions. Nematode reproduction on the wilt-susceptible cultivars, but not on the wilt-resistant one, was significantly increased by F. oxysporum f. sp. ciceris infections under controlled and field conditions.  相似文献   
1000.
Cardio pulmonary embarrassment was induced with thiopentone sodium in 35 healthy adult donkeys divided in to seven groups of five animals. “To effect” anaesthetic dose was (12.72 ± 0.69 mg/kg) which caused transient hypotension, tachycardia and hypoxemia. A stable fall in MAP 1. 6.77 ± 0.287 Kpa (50.78 ± 2.15 mmHg) and a flat EEG were considered to indicate acute circulatory insufficiency due to thiopentone overdose.  相似文献   
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