排序方式: 共有51条查询结果,搜索用时 31 毫秒
41.
MHB Santos MC Rabelo SI Guido JNC Torreão ES Lopes Júnior VJF Freitas PF de Lima MAL Oliveira 《Reproduction in domestic animals》2007,42(2):214-217
The aim of this study was to determine the period of genital tubercle (GT) migration using ultrasonography in Morada Nova sheep foetuses (n = 117) from natural mating (NM) and frozen embryo transfer (ET) to determine the window when foetal sexing can be determined. The examinations were performed using transrectal ultrasonography with a dual-frequency linear transducer (6.0 and 8.0 MHz) from day 30-54 of pregnancy at 48-h intervals. The period of GT migration of foetuses produced by NM varied from 36 to 46 days of pregnancy, resulting in an average of 39.5 +/- 2.9 days. For foetuses derived from ET, GT migration varied from 42 to 52 days of pregnancy with an average of 48.5 +/- 3.3 days, being possible the GT of foetuses from ET start to migrate 96 h later even if they are of the same gender. Migration of the GT occurred earlier (p < 0.05) in foetuses produced by NM and sexing accuracy for triplet pregnancies (77.8%) was significantly inferior (p < 0.05) to single (100%) and twin (92.9%) pregnancies for foetuses derived by NM. The results allow one to conclude that foetal sexing can be done from the 50th day onwards in foetuses produced by NM and from the 55th day onwards in foetuses derived from ET, and that multiple pregnancies compromise the sexing accuracy by ultrasonography. 相似文献
42.
Objective To compare the efficacy of moxidectin to ivermectin, oxibendazole and morantel against some gastrointestinal nematodes in horses.
Design Faecal egg count reduction after treatment.
Procedure A farm was selected where the population of small strongyles in horses was known to be resistant to oxibendazole. Horses were allocated to treatment groups based on faecal egg counts. After treatment, faecal samples were taken up to 109 days after treatment and faecal egg counts estimated. Faecal cultures were used to estimate the contribution of small and large strongyles to the faecal egg counts at each sampling.
Results Moxidectin (0.4 mg/kg) suppressed faecal egg counts for 109 days after treatment in most horses compared to 40 days with ivermectin (0.2 mg/kg), 13 days with morantel (9.4 mg/kg) and less than 13 days with oxibendazole (10 mg/kg). Most of the faecal egg count was attributable to small strongyles based on faecal culture, although Strongylus vulgaris was present in some samples in low numbers. Oxibendazole resistance in small strongyles was confirmed and a less than expected efficacy of morantel was also seen.
Conclusion Moxidectin was highly effective in reducing faecal egg counts after treatment for at least 12 weeks and up to 16 weeks in most horses. These horses were infected with a population of small strongyles known to be resistant to oxibendazole and possibly morantel. The duration of the reduction in faecal egg counts after treatment with moxidectin (0.4 mg/kg) was at least twice that of ivermectin (0.2 mg/kg) and greater than four times that for morantel and oxibendazole. 相似文献
Design Faecal egg count reduction after treatment.
Procedure A farm was selected where the population of small strongyles in horses was known to be resistant to oxibendazole. Horses were allocated to treatment groups based on faecal egg counts. After treatment, faecal samples were taken up to 109 days after treatment and faecal egg counts estimated. Faecal cultures were used to estimate the contribution of small and large strongyles to the faecal egg counts at each sampling.
Results Moxidectin (0.4 mg/kg) suppressed faecal egg counts for 109 days after treatment in most horses compared to 40 days with ivermectin (0.2 mg/kg), 13 days with morantel (9.4 mg/kg) and less than 13 days with oxibendazole (10 mg/kg). Most of the faecal egg count was attributable to small strongyles based on faecal culture, although Strongylus vulgaris was present in some samples in low numbers. Oxibendazole resistance in small strongyles was confirmed and a less than expected efficacy of morantel was also seen.
Conclusion Moxidectin was highly effective in reducing faecal egg counts after treatment for at least 12 weeks and up to 16 weeks in most horses. These horses were infected with a population of small strongyles known to be resistant to oxibendazole and possibly morantel. The duration of the reduction in faecal egg counts after treatment with moxidectin (0.4 mg/kg) was at least twice that of ivermectin (0.2 mg/kg) and greater than four times that for morantel and oxibendazole. 相似文献
43.
GRAEME ALLAN TIMOTHY PORTAS BENN BRYANT ROLFE HOWLETT DAVID BLYDE 《Veterinary radiology & ultrasound》2008,49(6):551-556
Distal ulna metaphyseal osteochondrosis was identified in seven captive bred cheetahs raised in Australia between 1984 and 2005. The disorder was characterized by bilateral carpal valgus conformation. In the metaphyseal region of the distal ulnae, an osteolucent defect that appeared as a proximal extension of the lucent physis was identified radiographically between 6 and 10 months of age. Ulna ostectomy was done to correct the angular limb deformity. Histologically, changes were identified in the osteolucent lesion that resembled osteochondrosis. We propose that the condition is probably familial and/or dietary in origin. 相似文献
44.
Frankliniella fusca resistance to neonicotinoid insecticides: an emerging challenge for cotton pest management in the eastern United States 下载免费PDF全文
45.
D Guillaume P Chavatte-Palmer Y Combarnous G Duchamp N Martinat P Nagy PF Daels 《Reproduction in domestic animals》2003,38(5):394-400
The aim of this study was to compare the effects of treatment with repeated injections of sulpiride (a dopamine D2 antagonist) on prolactin secretion and induced lactation in ovariectomized and intact adult mares and to verify if this induction was possible at the beginning and at the end of the birth season. Two experiments were carried out in September [experiment (expt) 1], and in March (expt 2), in France (48°N). In expt 1, three groups of five mares were tested: intact‐control, intact‐treated and ovariectomized‐treated mares. In expt 2, mares previously subjected to artificial photoperiod were assigned in two groups: four intact‐control and five intact‐treated mares. The cyclicity of intact mares was previously synchronized with PGF2α injections, then all the mares were in the follicular phase at the beginning of treatment. Sulpiride was intramuscularly injected (0.5 mg/kg of BW), twice a day. Mares were milked at 7:30, 11:45, 16:00 and 20:15 hours. Blood samples were collected every day during the treatment for progesterone, total oestrogen and prolactin assays. In the two experiments, only treated intact mares produced milk, with a large inter‐animal variability. Prolactin increase after sulpiride treatment was not so great in the ovariectomized‐treated mares as in the intact‐treated mares. The total correlations between prolactin, progesterone, oestrogen plasma concentrations and daily milk production were significant (0.57, 0.25, 0.17 respectively). This induction of lactation can be performed during the entire birth season in intact mares, but not in ovariectomized mares, indicating that steroids are necessary for this induction in mares treated by dopamine D2 antagonist. 相似文献
46.
Daniela T Pezzini Dominic D Reisig G David Buntin Alejandro I Del Pozo-Valdivia Fred Gould Silvana V Paula-Moraes Francis PF Reay-Jones 《Pest management science》2023,79(10):3493-3503
BACKGROUND
Helicoverpa zea, an economic pest in the south-eastern United States, has evolved practical resistance to Bacillus thuringiensis (Bt) Cry toxins in maize and cotton. Insect resistance management (IRM) programs have historically required planting of structured non-Bt maize, but because of its low adoption, the use of seed blends has been considered. To generate knowledge on target pest biology and ecology to help improve IRM strategies, nine field trials were conducted in 2019 and 2020 in Florida, Georgia, North Carolina, and South Carolina to evaluate the impact of Bt (Cry1Ab + Cry1F or Cry1Ab + Cry1F + Vip3A) and non-Bt maize plants in blended and structured refuge treatments on H. zea pupal survival, weight, soil pupation depth, adult flight parameters, and adult time to eclosion.RESULTS
From a very large sample size and geography, we found a significant difference in pupal mortality and weight among treatments in seed blends with Vip3A, implying that cross-pollination occurred between Bt and non-Bt maize ears. There was no treatment effect for pupation depth, adult flight distance, and eclosion time.CONCLUSION
Results of this study demonstrate the potential impact of different refuge strategies on phenological development and survival of an important pest species of regulatory concern. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献47.
48.
KF TRUEMAN RJ THOMAS AR MACKENZIE LE EAVES PF DUFFY 《Australian veterinary journal》1996,74(5):367-369
Objective: To investigate the presence of Salmonella Dublin in Queensland cattle.
Design: An epidemiological study using diagnostic laboratory information and farm records.
Procedure: Outbreaks of gastroenteritis or pneumonia in calves, and abortions and enteritis in cows were routinely investigated for the presence of salmonellae. Where S Dublin was isolated, attempts were made to gather further epidemiological information.
Results: Prior to 1983 only two outbreaks of S Dublin have been recorded in Queensland dairy cattle. In 1983 S Dublin abortions were diagnosed in dairy heifers introduced from southern Australia to south-east Queensland. Sampling indicated that at least 10% of the 500 introduced heifers were faecal excretors of S Dublin. On 3 of the 7 farms from which S Dublin was recorded, infection spread to other cattle that were in contact. From February 1985 to February 1996, 29 outbreaks of S Dublin in cattle occurred on 29 farms (28 in south east Queensland and 1 in north Queensland). Calves were primarily affected. Continuing outbreaks were confirmed on only 4 of these 29 farms. On 15 farms S Dublin infections were associated with the purchase of infected calves or cows, while another farm adjoined 2 previously infected farms. No source of S Dublin was evident for the other 13 farms, where histories were often inadequate.
Conclusion: There has been a marked increase in S Dublin outbreaks in Queensland dairy cattle since 1983. Introduction of S Dublin carrier and aborting dairy heifers from southern Australia, where S Dublin is not uncommon, was associated with the initial outbreaks. 相似文献
Design: An epidemiological study using diagnostic laboratory information and farm records.
Procedure: Outbreaks of gastroenteritis or pneumonia in calves, and abortions and enteritis in cows were routinely investigated for the presence of salmonellae. Where S Dublin was isolated, attempts were made to gather further epidemiological information.
Results: Prior to 1983 only two outbreaks of S Dublin have been recorded in Queensland dairy cattle. In 1983 S Dublin abortions were diagnosed in dairy heifers introduced from southern Australia to south-east Queensland. Sampling indicated that at least 10% of the 500 introduced heifers were faecal excretors of S Dublin. On 3 of the 7 farms from which S Dublin was recorded, infection spread to other cattle that were in contact. From February 1985 to February 1996, 29 outbreaks of S Dublin in cattle occurred on 29 farms (28 in south east Queensland and 1 in north Queensland). Calves were primarily affected. Continuing outbreaks were confirmed on only 4 of these 29 farms. On 15 farms S Dublin infections were associated with the purchase of infected calves or cows, while another farm adjoined 2 previously infected farms. No source of S Dublin was evident for the other 13 farms, where histories were often inadequate.
Conclusion: There has been a marked increase in S Dublin outbreaks in Queensland dairy cattle since 1983. Introduction of S Dublin carrier and aborting dairy heifers from southern Australia, where S Dublin is not uncommon, was associated with the initial outbreaks. 相似文献
49.
PF LEWIS 《Australian veterinary journal》1994,71(5):133-135
SUMMARY Common tiger snake (Notechis scutatus) venom was administered experimentally to dogs at doses from 0.25 lethal dose (LD) to 20 LD. Haemolysis and increased creatine kinase values occurred rapidly after injection of sublethal (subparalytic) doses, but the clotting time of blood was extended and blood became incoagulable only when dogs were dosed with 10 LD or more of venom. Haemolysis, although of a low threshold of toxicity, was not severe and should not greatly affect the lethality of the venom. Coagulopathy is a sign that the dog has been lethally envenomed and will need to be given antivenom if skeletal muscle paralysis is to be overcome. 相似文献
50.
A dog was presented with a 2 year history of polyuria and polydipsia due to pituitary-dependent hyperadrenocorticism. A low-dose dexamethasone suppression test and measurement of plasma ACTH concentration confirmed the diagnosis. Treatment was instituted with mitotane at 44 mg/kg/day and then 88 mg/kg/d without complete resolution of signs. The dog collapsed with signs consistent with liver disease and was euthanased. Necropsy revealed a phaeochromocytoma of the left adrenal medulla with extensive metastases to the liver. A chromophobe adenoma of the pars intermedia of the pituitary was found. 相似文献