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A study was conducted to assess the combined effect of heat stress and nutritional restriction on growth and reproductive performances in Malpura rams. Twenty‐eight adult Malpura rams (average body weight (BW) 66.0 kg) were used in this study. The rams were divided into four groups: CON (n = 7; control), HES (n = 7; heat stress), NUS (n = 7; nutritional stress) and COS (n = 7; combined stress). The study was conducted for a period of 2 months. CON and HES rams had ad libitum access to their feed while NUS and COS rams were under restricted feed (30% intake of CON rams) to induce nutritional stress. The HES and COS rams were kept in climatic chamber at 42 °C and 55% relative humidity for 6 h a day between 10 : 00 h and 16 : 00 h to induce heat stress. Body weight increased significantly (p < 0.05) in CON as compared to NUS and COS. When compared within groups, scrotal width morning, scrotal width afternoon, scrotal circumference morning and scrotal circumference afternoon were significantly (p < 0.05) larger in CON while smaller in COS rams. The higher testicular length was recorded both during morning (p < 0.05) and afternoon (p < 0.01) in COS rams while the lowest in NUS rams. The highest plasma testosterone concentration was recorded in CON and lowest in COS rams. Semen volume and mass motility also differed significantly (p < 0.05) between the groups. The highest semen volume and mass motility was recorded in CON and NUS while lowest in both HES and COS rams. It can be concluded from this study that when two stressors occur simultaneously, they may have severe impact on reproductive performance of rams.  相似文献   
295.
The objective of the present study was to evaluate a potential of Schizochytrium microalga oil to alleviate possible negative effects of high‐fat‐high‐energy diets. Forty adult male rats (Wistar Albino) were fed 7 weeks the diet containing beef tallow + evaporated sweetened milk (diet T) intended to cause mild obesity and low‐grade systemic inflammation. Consequently, the animals were divided into four groups by 10 animals each and fed either the T‐diet (control) or the diet containing 6% of safflower oil (S), 6% of fish oil (F) and 6% of Schizochytrium microalga oil (A), respectively, for another 7 weeks. The A‐diet decreased (p < 0.05) live weight to 86% and glycaemia to 85% of control, respectively; an effect of the S‐ and F‐diet on these markers was insignificant (p > 0.05). In comparison with control, higher (p < 0.05) deposition of eicosapentaenoic acid (EPA) + docosahexaenoic acid (DHA) in the epididymal adipose tissue (EAT) of the A‐rats correlated with increased (p < 0.05) plasma adiponectin concentration, but it was without the effect (p > 0.05) on cellular adiponectin content in the EAT. Higher (p < 0.05) EPA+DHA deposition in the liver of the A‐rats correlated with higher expression (149% of control; p < 0.05) of the gene coding for peroxisome proliferator‐activated receptor gamma, and with lower expression (82% and 66%; p < 0.05) of the genes coding for adiponectin receptors AdipoR1 and AdipoR2; no relationship to the expression of receptor GPR120 was found. The A‐diet did not affect amount of the nuclear fraction of the nuclear factor kappa B in the liver, but increased plasma level of anti‐inflammatory cytokine TGF‐β1 (p < 0.05). The presented data agree with results of other in vivo rodent and human studies, but not with literature data regarding in vitro experiments: it can be concluded that the effects of dietary oils on inflammatory markers need further investigation.  相似文献   
296.
The phylogenetic layout of the genotyped (30 microsatellite) 18 sheep breeds in this study demands and provides the opportunity to evaluate both neutral and adaptive components of genetic diversity in a naturally and artificially selected and subdivided sheep population. Seven Pramenka strains from Bosnia and Herzegovina and Croatia characterized by a very low intensity of artificial selection, preserved the highest neutral genetic variability. Eight central and north‐western European breeds under considerable artificial isolation and selection preserved the lowest genetic variability. Only combinations of various phylogenetic parameters offer a reasonable explanation for underlying evolutionary forces working in the investigated island and mainland sheep breeds under variable natural and artificial selection. More than 60% of total genetic, diversity was allocated to virtually unselected Pramenka strains, and an additional 25% to native moderately selected Graue Gehoernte Heidschnucke and intensively selected Ostfriesische Milchschafe. Some economically very important breeds and strains did not contribute to a pool with maximal genetic diversity, while they play an important role in the cultural heritage of respective countries.  相似文献   
297.
OBJECTIVE: To determine ECG and echocardiographic measurements in healthy anesthetized Grevy's zebras (Equus grevyi). ANIMALS: 20 healthy zebras. PROCEDURES: Auscultation, base-apex ECG, and echocardiography were performed on anesthetized zebras. RESULTS: Low-grade systolic murmurs were detected in the left basilar region in 4 of 20 zebras. Evaluation of ECGs from 19 zebras revealed sinus rhythm with a predominantly negative QRS complex and a mean +/- SD heart rate of 67 +/- 10 beats/min. Echocardiograms of sufficient image quality were obtained for 16 zebras. Interventricular septal thickness in diastole, left ventricular chamber in diastole and systole, left atrial diameter, and left ventricular mass were significantly and moderately correlated with estimated body weight (r values ranged from 0.650 to 0.884). Detectable swirling of blood in the right and sometimes the left ventricles was detected in 9 of 16 zebras, whereas physiologic regurgitation of blood was detected for the aortic valve in 3 zebras, pulmonary valve in 2 zebras, mitral valve in 2 zebras, and tricuspid valve in 1 zebra. CONCLUSIONS AND CLINICAL RELEVANCE: Results of this study provide reference information for use in the cardiac evaluation of anesthetized Grevy's zebras.  相似文献   
298.
CASE DESCRIPTION: A 6.5-year-old female eastern black and white colobus monkey (Colobus guereza) was evaluated after acute onset of ataxia and inappetence. CLINICAL FINDINGS: The monkey was ataxic and lethargic, but no other abnormalities were detected via physical examination, radiography, or clinicopathologic analyses. During the next 2 days, the monkey's clinical condition deteriorated, and its WBC count decreased dramatically. Cytologic examination of a CSF sample revealed marked lymphohistiocytic inflammation. TREATMENT AND OUTCOME: Despite supportive care, the monkey became apneic; after 20 hours of mechanical ventilation, fatal cardiac arrest occurred. At necropsy, numerous petechiae were detected within the white matter tracts of the brain; microscopic lesions of multifocal necrosis and hemorrhage with intranuclear inclusions identified in the brain and adrenal glands were consistent with an acute herpesvirus infection. A specific diagnosis of herpesvirus papio-2 (HVP-2) infection was made on the basis of results of serologic testing; PCR assay of tissue specimens; live virus isolation from the lungs; and immunohistochemical identification of the virus within brain, spinal cord, and adrenal gland lesions. Via phylogenetic tree analysis, the colobus HVP-2 isolate was grouped with neuroinvasive strains of the virus. The virus was most likely transmitted to the colobus monkey through toys shared with a nearby colony of baboons (the natural host of HVP-2). CLINICAL RELEVANCE: To the authors' knowledge, this is the first reported case of natural transmission of HVP-2 to a nonhost species. Infection with HVP-2 should be a differential diagnosis for acute encephalopathy in primate monkeys and humans, particularly following exposure to baboons.  相似文献   
299.
A 4-year-old Arab mare was diagnosed with disseminated cryptococcosis, including osteomyelitis of the proximal phalanx of the left hind limb, osteomyelitis with associated soft tissue granuloma of a rib and disseminated, large cryptococcal nodules in the lungs. The lesion in the dorsoproximal aspect of the proximal phalanx had a large area of cortical lysis with spiculated periosteal new bone and extensive soft tissue swelling. The affected rib had a pathological fracture. Cryptococcal osteomyelitis has not been previously reported in horses but should be considered as a differential diagnosis, particularly in endemic regions.  相似文献   
300.
OBJECTIVE: To determine clinical characteristics and mode of inheritance of seizures in a family of Standard Poodles. DESIGN: Case series. ANIMALS: 90 Standard Poodles descended from the same maternal bloodline (30 with probable idiopathic epilepsy [PIE] and 60 without any history of seizures). PROCEDURES: Researchers contacted owners to determine whether dogs had ever had any seizures and, if so, the nature of any such seizures and any potential underlying causes. Dogs were considered to have PIE if they were between 6 months and 7.5 years old at the time of seizure onset and had no evidence of any underlying cause. To determine the mode of inheritance, segregation analyses were designed to allow the family to be analyzed as a whole, as opposed to as nuclear families. Competing models of inheritance were compared statistically for their ability to explain the data. RESULTS: Of the dogs with PIE, 28 (93%) had focal onset seizures with or without secondary generalization. Median age of onset was 3.7 years; 6 dogs were > 5 years old at the onset of seizures. Segregation analyses strongly suggested that PIE was inherited as a simple recessive autosomal trait with complete or almost complete penetrance. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that in this family of Standard Poodles, PIE was inherited as a simple recessive autosomal trait with complete or almost complete penetrance. Seizures often had focal, as opposed to generalized, onsets, and it was not uncommon for seizures to begin after 5 years of age.  相似文献   
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