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991.
A study was conducted to determine the variations in physical characters and immunocompetence among scavenging local chicken ecotypes in Tanzania. Eighty-four adult scavenging local chickens from four eco-climatic regions of Tanzania were studied. Measurements of adult body weight, body length, shank length and egg weight and observations of plumage colour and pattern, earlobe colour, skin colour and the shape of the comb were conducted. The antibody response to sheep red blood cells, serum haemolytic complement and the cutaneous response to phytohaemagglutinin-P were assessed. Five ecotypes were identified and named Mbeya, Morogoro-medium, Ching'wekwe, Kuchi and Singamagazi. Singamagazi and Kuchi were significantly heavier, with longer shanks and heavier eggs than the other ecotypes. The average adult body weight for males ranged from 1621 g (Mbeya) to 2915 g (Singamagazi). Average female weights ranged from 1108 g (Morogoro-medium) to 2020 g (Singamagazi). Mean egg weights ranged from 37.65 g (Ching'wekwe) to 45.61 (Singamagazi). The Kuchi had mostly rose and walnut combs, while the other ecotypes were mostly single combed. In each ecotype there were chickens with a high or low antibody response to red blood cells, but there was a significant difference between the ecotypes.  相似文献   
992.
Two trials were conducted to determine the effects of breed type, backgrounding program, and backfat end point (USBFEP) as determined by ultrasound on the performance and carcass characteristics of feedlot steers. Trial 1 utilized 144 large-framed Charolais- (304.6 +/- 16.3 kg) and 144 medium-framed Hereford-cross steers (294.8 +/- 20.9 kg). Trial 2 utilized 88 medium-framed Angus (289.5 +/- 15.0 kg), 88 large-framed Charolais- (299.8 +/- 17.7 kg), and 88 medium-framed Hereford-cross (291.1 +/- 20.9 kg) steers. Within breed type, short- (70 d) or long-term (126 d) backgrounding programs (Trial 1) and 6- or 12-mm USBFEP (Trials 1 and 2) were assigned. In both trials, carcass size was greater (P < 0.05) for the large-framed Charolais-cross steers, longer backgrounding, and fatter USBFEP treatments. Lean meat yield was greater (P < 0.05) for Charolais- than Hereford-cross steers (Trial 1) and for the leaner USBFEP (Trials 1 and 2). Marbling was greater (P < 0.05) for Angus- (Trial 2) and Charolais- (Trials 1 and 2) than Hereford-cross steers (Trials 1 and 2) and for the fatter end point (Trials 1 and 2). It was concluded that breed type, backgrounding program, and USBFEP were effective in altering growth and could be used to target carcass traits of interest for value-based marketing programs.  相似文献   
993.
OBJECTIVE: To evaluate the effectiveness of 2 potential endothelin (ET)-1 antagonists in blocking the contractile responses of equine colonic vessels to increasing concentrations of ET-1. SAMPLE POPULATION: Mesenteric vessels from 6 clinically healthy horses. PROCEDURE: Colonic vessels (arterial and venous rings) were placed in organ baths with oxygenated Tyrode solution at 37 C. Each was attached to a force transducer interfaced with a polygraph, and 2 g of tension was applied and equilibrated for 45 minutes. Then, B-1 (PD 142893) and B-2 (PD 145065) ET-1 antagonists were tested. One ring from each vessel type was used as a control for determining concentration-response relationships of ET-1 (10(-10) to 10(-6)M). Three rings of each vessel type were incubated with 3 concentrations of each antagonist (10(-7), 10(-6), and 10(-5) M) for 30 minutes before ET induced contractions were determined. The maximum contractile response and pA2 values were determined. RESULTS: Vessels contracted in a concentration-dependent manner to ET-1. Arteries responded slowly but reached greater contractions. Veins responded immediately with sustained contractions. Both antagonists inhibited contractions in a concentration-dependent manner with significant differences at 10(-6) and 10(-5)M for arteries and 10(-5) M for veins. Complete blockade of contractions was observed with B-2 (10(-5)M). The pA2 values for B-1 were 8.26 and 6.82 for arteries and veins, respectively, whereas they were 8.25 and 7.21 for B-2. CONCLUSION AND CLINICAL RELEVANCE: Both antagonists effectively blocked ET-1-induced contractions of equine colonic vessels. Because B-2 is water soluble and caused complete blockade at 10(-5) M, it appears to be the preferred antagonist.  相似文献   
994.
OBJECTIVE: To investigate the effects of acupuncture on neural activity detected by use of manganese-enhanced functional magnetic resonance imaging (fMRI) and elucidate the relationship between somatic acupoint stimulation and brain activation. ANIMALS: 40 New Zealand White rabbits. PROCEDURE: Manganese-enhanced fMRI was performed in anesthetized rabbits manipulated with electroacupuncture (EA) on Zusanli (ST-36) and Yanglingquan (GB-34) acupoints. Image acquisition was performed on a 1.5T superconductive clinical scanner with a circular polarized extremity coil. T1-weighted images were acquired sequentially as follows: baseline, after mannitol injection, after manganese infusion, and 5 and 20 minutes after initiation of EA. RESULTS: Changes in focal neural activity were detected by use of manganese-enhanced fMRI. Stimulation on Zusanli (ST-36) for 5 minutes resulted in activation of the hippocampus, whereas stimulation on Yanglingquan (GB-34) resulted in activation of the hypothalamus, insula, and motor cortex. Activation became less specific after 20 minutes of EA. Furthermore, stimulation on ipsilateral acupoints led to bilateral brain activation. CONCLUSIONS AND CLINICAL RELEVANCE: Each acupoint has a corresponding cerebral linkage, and stimulation on these points resulted in time-dependent neural activation. Understanding the linkage between peripheral acupoint stimulation and central neural pathways may provide a useful guide for clinical applications of acupuncture.  相似文献   
995.
An adult female bearded vulture (Gypaetus barbatus) in the Tel Aviv University Research Zoo was found dead without previous clinical signs. The predominant pathologic changes were considerable bloody content in the intestines and enlargement of the liver, which had a rubbery consistency with color changes. Microscopic lesions consisted of multifocal histiocytic infiltration in the liver. Newcastle disease virus (NDV) was isolated from a cloacal swab and from the lungs and liver. Intracerebral pathogenicity index of the virus, as estimated in 1-day-old chicks, was repeated three times and had an average value of 1.68, indicating a velogenic strain. Numerous Clostridium septicum bacteria were found on the intestinal surface, but bioassays in which they were orally administered into chickens and mice revealed that, even though they were heavily multiplied in the intestines, they were nonpathogenic. It seems that NDV, documented for the first time in a bearded vulture in Israel, was the likely cause of sudden death.  相似文献   
996.
Tachyzoites of Toxoplasma gondii have been found in the milk of sheep, goats, cows and mice and infection by ingestion of raw goat milk has been documented in humans. Lactational transmission from infected cats to their kittens is suspected but the organism has not been detected in the milk. The purpose of this study was to demonstrate the presence of T. gondii in the milk of experimentally infected cats. Pregnant specific pathogen free cats were inoculated orally with T. gondii at various times prior to parturition. Feces were examined for oocyst shedding after sugar solution centrifugation. Milk was collected for polymerase chain reaction (PCR) and bioassay in mice. T. gondii was detected in the milk of five of six cats by either bioassay or PCR.  相似文献   
997.
An eight-year-old neutered female Persian cat with a four-year history of relapsing skin disease, characterised by ulcerated nodules with a yellow granular discharge, was examined. A diagnosis of granulomatous dermatitis and panniculitis (pseudomycetoma) caused by Microsporum canis was made on the basis of history, clinical signs, histopathological examination of skin biopsy specimens and culture of macerated tissue. Because previous therapy, comprising repeated surgical excision and the administration of griseofulvin and itraconazole, had not been successful, terbinafine was administered for an eight-month period. However, lesions progressed despite this treatment and the cat was euthanased.  相似文献   
998.
Bovine neosporosis: immunoblot improves foetal serology.   总被引:5,自引:0,他引:5  
The purpose of the study is the comparative evaluation of the immunofluorescent antibody test (IFAT) and an immunoblot (IB) test for the examination of foetal fluids for specific antibodies against Neospora caninum. Peritoneal and pleural fluids as well as abomasal contents were analysed. The results of the serological examinations were compared to those obtained by histological, immunohistochemical, and PCR analysis of foetal tissues as well as to the results of maternal serological examinations. Fluids were used undiluted in the IB and reactions against six immunodominant antigens were recorded. When the recognition of at least two immunodominant antigens was regarded as positive, the agreement of the IB with other diagnostic methods was good to moderate as characterised by kappa-values of 0.76 (histology/immunohistochemistry), 0.69 (maternal serology) and 0.54 (PCR on foetal tissues). The IB results agreed better with the results of the other diagnostic methods than those of the IFAT. The higher relative sensitivity of the IB was regarded as the main reason for the better agreement. However, also the specificity of the IB was superior to that of the IFAT in relation to histology/immunohistochemistry, maternal serology and PCR.  相似文献   
999.
1000.
Palicourea species may produce bovine toxicity. Palicourea corymbifera grows in terra firme forests within the Amazon rain forest and in Tropical America, particularly in spots that gave place to gazing areas. The lyophilized extract done with the aerial organs of P. corymbifera were analyzed in male and female mice. Results revealed a significant toxicity: LD50 was 1.10 (1.04-1.15)g/kg for male mice, and 1.05 (1.00-1.10)g/kg for female mice. Locomotion was affected as well as there were reflexes linked to environmental stimuli in addition to changes in posture. Progressive central nervous system stimulus signs such as trembling and convulsions were detected, the latter followed by the animal's death. Macroscopic histopathological exams performed on the liver, kidneys and lungs of mice submitted to necropsy did not indicate the existence of lesions. General activity of animals, measured in an open field, was reduced as a result of the administration of the extract. Duration of locomotion and rearing frequency were reduced, in opposition to an increase in the duration of immobility. Thin layer chromatography analysis showed that monofluoroacetic acid is present in the lyophilized extract, but other qualitative techniques as gas chromatography/mass spectrometry and 19F nuclear magnetic resonance showed that the MFAA was not present in the extract, and that the toxicity is related to other compound, although the toxic profile is very similar to that of MFAA. P. corymbifera was shown to be significantly toxic to laboratory animals and investigation of the possible toxic substance shall be done.  相似文献   
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