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991.
992.
S.R. Isberg P.C. Thomson F.W. Nicholas S.G. Barker & C. Moran 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2005,122(6):370-377
Crocodile morphometric (head, snout‐vent and total length) measurements were recorded at three stages during the production chain: hatching, inventory [average age (±SE) is 265.1 ± 0.4 days] and slaughter (average age is 1037.8 ± 0.4 days). Crocodile skins are used for the manufacture of exclusive leather products, with the most common‐sized skin sold having 35–45 cm in belly width. One of the breeding objectives for inclusion into a multitrait genetic improvement programme for saltwater crocodiles is the time taken for a juvenile to reach this size or age at slaughter. A multivariate restricted maximum likelihood analysis provided (co)variance components for estimating the first published genetic parameter estimates for these traits. Heritability (±SE) estimates for the traits hatchling snout‐vent length, inventory head length and age at slaughter were 0.60 (0.15), 0.59 (0.12) and 0.40 (0.10) respectively. There were strong negative genetic (?0.81 ± 0.08) and phenotypic (?0.82 ± 0.02) correlations between age at slaughter and inventory head length. 相似文献
993.
In Uganda, control of vector-borne diseases is mainly in form of vector control, and chemotherapy. There have been reports
that acaricides are being misused in the pastoralist systems in Uganda. This is because of the belief by scientists that intensive
application of acaricide is uneconomical and unsustainable particularly in the indigenous cattle. The objective of this study
was to investigate the strategies, rationale and effectiveness of vector-borne disease control by pastoralists. To systematically
carry out these investigations, a combination of qualitative and quantitative research methods was used, in both the collection
and the analysis of data. Cattle keepers were found to control tick-borne diseases (TBDs) mainly through spraying, in contrast
with the control of trypanosomosis for which the main method of control was by chemotherapy. The majority of herders applied
acaricides weekly and used an acaricide of lower strength than recommended by the manufacturers. They used very little acaricide
wash, and spraying was preferred to dipping. Furthermore, pastoralists either treated sick animals themselves or did nothing
at all, rather than using veterinary personnel. Oxytetracycline (OTC) was the drug commonly used in the treatment of TBDs.
Nevertheless, although pastoralists may not have been following recommended practices in their control of ticks and tick-borne
diseases, they were neither wasteful nor uneconomical and their methods appeared to be effective. Trypanosomosis was not a
problem either in Sembabule or Mbarara district. Those who used trypanocides were found to use more drugs than were necessary. 相似文献
994.
AIM: To investigate the nature of a neurological disease in Wiltshire sheep. METHODS: Three affected lambs were examined, humanely killed and necropsied. Selected neurological tissues were examined by light and electron microscopy. RESULTS: Primary neurological lesions were confined to the cerebellum and were characterised by loss of Purkinje cells and the presence of large hypertrophied dendrites of surviving Purkinje cells. These contained stacks of smooth endoplasmic reticulum. There was hyperplasia and cell swelling of Bergmann glia. Mild Wallerian-type degeneration affected white matter in the cerebellum and spinal cord. CONCLUSION: The cerebellar lesions were of a degenerative and reactive rather than hypoplastic nature. These, and the history, suggest a genetic cause with putative inheritance as an autosomal recessive trait. Accordingly, the disorder is described as a cerebellar abiotrophy. 相似文献
995.
The objective of the study was to determine the disinfection efficacy of aerosolizing (cold fogging) Virkon S on survival of Stahpylococcus aureus and Salmonella enterica on different surfaces. Two experiments were conducted in different locations. Salmonella enterica and S. aureus were grown in broth culture and then seeded into pre-marked areas in each location and allowed to dry. Virkon S (1%) was aerosolized into the rooms (approximately 1L of per 30 m(3)). Samples were collected pre- and post-fogging for quantitative cultures to evaluate the efficacy of aerial disinfection. The reduction of S. enterica or S. aureus counts ranged from 3.40 to 0.95 log(10) (Salmonella) or 4.92 to 0.02 log(10) (Staphylococcus). The greatest reduction was evident in samples collected from non-porous horizontal surfaces, which were not obstructed from the air flow. These results indicate that fogging with Virkon S could be beneficial in routine disinfection of pre-cleaned surfaces. The benefits of routine use of cold fogging with Virkon S in veterinary hospital settings would include its wide-range antimicrobial action and minimal working-men power required to disinfect large areas. Also, fogging would potentially minimize microbial contamination in the hard to reach areas. 相似文献
996.
An eight-year-old, female springer spaniel was treated for metastatic insulinoma with a single intravenous dose of 500 mg/m2 streptozotocin (SZN), and pre- and post-treatment diuresis. A tapering dose of corticosteroids was also administered over a 28 day period. SZN and corticosteroid administration resulted in resolution of hypoglycaemia and subsequent development of diabetes mellitus. Further metastases caused cervical spinal pain and the dog was euthanased 118 days after SZN administration. SZN can be safely used for the treatment of canine insulinoma, but, when compared with other published cases, a marked variation in clinical response to this drug exists and further study is warranted. 相似文献
997.
998.
D E Hutchens A J Paul J A DiPietro T F Lock C J Jones D D Rowley R W Wallace 《Veterinary parasitology》1999,83(1):79-85
A controlled test was conducted to assess the efficacy bioequivalence of a single dose of 0.5% fenbendazole (FBZ) top dress pellets to a 10% FBZ suspension formulation (Panacur suspension 10%, Hoechst Roussel Vet). Thirty horses with naturally-acquired parasite infections, in replicates of three, were used. Strongyle egg per gram counts were not significantly different (P>0.1) between groups pretreatment, but FBZ treated groups were significantly different from the control group post-treatment. At necropsy, which occurred seven to nine days post-treatment, two methods of nematode recovery were compared to assess whether a small aliquot can be used in a control test to determine efficacy against large as well as small strongyles. Both post mortem worm recovery techniques revealed similar efficacies of both formulations (>95%) against small and large strongyles, but large differences in the number of worms recovered. Six species of small strongyles comprised 96% of all the small strongyles recovered: Coronocyclus coronatus, Cylicocyclus insigne, Cylicostephanus longibursatus, Cylicocyclus brevicapsulatus, Cylicocyclus nassatus, and Cyathostomum catinatum. The results of this study demonstrated therapeutic bioequivalence between FBZ formulations and also the need to sample at least a 10% aliquot to accurately estimate number of large strongyles. No adverse reactions to treatment were detected. 相似文献
999.
D.D. Frisbie DVM MS Diplomate ACVS G.W. Trotter DVM MS Diplomate ACVS B.E. Powers DVM PhD Diplomate ACVP W.G. Rodkey DVM Diplomate ACVS J.R. Steadman MD R.D. Howard DVM PhD Diplomate ACVS R.D. Park DVM PhD Diplomate ACVR C.W. McIlwraith BVSc PhD Diplomate ACVS 《Veterinary surgery : VS》1999,28(4):242-255
OBJECTIVE: To evaluate the effect of arthroscopic subchondral bone microfracture on healing of large chondral defects in horses. STUDY DESIGN: Short- (4 months) and long-term (12 months) in vivo experimental chondral defect model. ANIMALS: 10 horses, aged 2 to 5 years. METHODS: Each horse had a 1 cm2 full-thickness chondral defect created in both radial carpal bones and both medial femoral condyles. One carpus and one femoral condyle of each horse had the subchondral bone plate under the defect perforated using an orthopedic awl. All horses were exercised, five horses were evaluated after 4 months and five horses after 12 months. Gross, histologic, and histomorphometric examination of defect sites and repair tissues was performed, as was collagen typing of the repair tissue. RESULTS: On gross observation a greater volume of repair tissue filled treated defects (74%) compared with control defects (45%). Histomorphometry confirmed more repair tissue filling treated defects, but no difference in the relative amounts of different tissue types was observed. There was an increased percentage of type II collagen in treated defects compared with control defects and evidence of earlier bone remodeling as documented by changes in porosity. CONCLUSIONS: In full-thickness chondral defects in exercised horses, treatment with subchondral bone microfracture increased the tissue volume in the defects and the percentage of type II collagen in the tissue filling the defects when compared to nontreated defects. CLINICAL RELEVANCE: No negative effects of the microfracture technique were observed and some of the beneficial effects are the basis for recommending its use in patients cases with exposed subchondral bone. 相似文献
1000.
J Tetens A C Bueno J L Cornick-Seahorn G Hosgood S C Eades R M Moore 《American journal of veterinary research》1999,60(9):1140-1147
OBJECTIVE: To determine hemodynamic and metabolic effects of IV infusion of ATP-MgCl2 combination and maximal safe IV infusion rate in conscious horses. ANIMALS: 6 adult female horses. PROCEDURE: All horses received an IV infusion of ATP-MgCl2 combination, beginning at a rate of 0.05 mg of ATP/kg of body weight/min, which was increased by 0.05 mg/kg/min increments at 10-minute intervals until a rate of 1.0 mg/kg/min was achieved. Data were collected prior to the start of the infusion, at the end of each infusion rate, and at 15-minute intervals for the next hour after discontinuation of the infusion. Measured or calculated hemodynamic variables included cardiac output, cardiac index, heart rate, stroke volume, systemic and pulmonary arterial pressures, and systemic and pulmonary vascular resistances. Arterial blood gas tensions, CBC, plasma biochemical profiles, urine volume and specific gravity, and selected clinical signs of disease also were evaluated. RESULTS: Intravenous infusion of ATP-MgCl2 significantly increased cardiac output, decreased systemic vascular resistance, and caused mild pulmonary hypertension. Magnitude of the hemodynamic alterations was dependent on rate of infusion. Maximal safe infusion rate for these horses was 0.3 mg/kg/min. All horses became lethargic, and their appetites diminished during the infusion; 5 horses had mild signs of abdominal discomfort. Flank sweating was observed in all horses as infusion rate increased. Urine volume and specific gravity and hematologic, biochemical, and arterial blood gas alterations were detected during and after infusion. CONCLUSIONS AND CLINICAL RELEVANCE: Intravenous administration of ATP-MgCl2 in healthy, conscious, adult horses caused various metabolic and hemodynamic alterations that were without appreciable detrimental effects. 相似文献