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Objective   To determine the effectiveness of a topical anaesthetic formulation (Tri-Solfen) with or without the administration of a non-steroidal anti-inflammatory drug (carprofen) on the pain and distress response associated with ring or surgical castration of ram lambs.
Procedures   Merino ram lambs (n = 78) were allocated to 10 treatment groups: 4 groups of knife-castrated lambs and 4 groups of ring-castrated lambs received carprofen (4 mg/kg SC) and Tri-Solfen; 2 control groups (sham) received carprofen at 0 or 4 mg/kg SC. Measurements included plasma cortisol and haptoglobin concentrations, haematology, and behaviour, including posture.
Results   Knife-castrated lambs had higher peak cortisol and integrated cortisol responses for the first 6 h after treatment and greater concentration s of circulating acute phase proteins than ring-castrated lambs, both of which were significantly different from the sham controls. Tri-Solfen applied to the knife castration wound significantly reduced both the peak plasma cortisol concentration and the integrated cortisol response for the first 6 h and improved lying behaviour in the first 12 h. Carprofen reduced the cortisol response to knife castration at 30 min, but elevated the cortisol responses at 24 and 48 h. Carprofen nearly halved the number of acute pain behaviours associated with ring castration. There were no significant additive or synergistic effects from combining the analgesic treatments. Tri-Solfen applied to the tail wound provided no detectible benefits during ring castration + tail docking.
Conclusions   The physiological and behavioural responses suggest that ring castration has less impact on the lamb than knife castration. The specific analgesic treatments can provide modest amelioration of the pain and discomfort associated with castration. Alternative doses or application methods may enhance their efficacy.  相似文献   
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为了探寻不同发育期朝鲜球坚蚧的有效防治新措施,根据朝鲜球坚蚧不同发育阶段的形态特征和生物学习性,对不同龄期的若虫采取刮皮涂干、树干注射和常规喷雾等措施进行防治.试验结果表明;在施药方法上,刮皮涂干和常规喷雾是最为适用的;在药效方面,在1龄若虫期喷雾施用的几种药剂中醋盐合剂对1龄若虫的喷洒防效达到了90%以上.通过施用脱叶剂处理叶片的方法来防治2龄若虫,试验所设3种浓度的脱叶剂均能间接起到防治作用,其效果均达到了95%以上.在3龄若虫期喷雾施用的几种药剂中95%酒精合剂的喷洒防效达到了90%以上.涂干防治3龄若虫期供试的几种药剂中,20%吡虫啉可溶性液剂1∶10的稀释液防效达到了90%以上.  相似文献   
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The bulbourethral glands of 323 Bos indicus or B. indicus crossbred bulls more than 1 1/2 years old were examined in an abattoir study. Bulbourethral adenitis was diagnosed grossly and confirmed by histological examination in 4 (1.2%). Unilateral chronic interstitial inflammation was seen in 2 cases; one of these was associated with a degenerative-type seminal vesiculitis. In the others adenitis was bilateral; in one case it was associated with a concretion and foreign (plant) material in the principal duct of the left bulbourethral gland; in the other bilateral case, numerous calculi were present and microscopically, a chronic active and diffuse inflammation was observed. Chemical analysis of the calculi showed calcium oxalate and tricalcium phosphate to be the most important components. Corynebacterium spp was isolated from the lesion with multiple calculi but attempts to isolate Chlamydia spp, Mycoplasma spp and Brucella abortus from the 4 adenitis cases were unsuccessful. Congenital abnormalities such as glandular fusion (2.2%) or unilateral aplasia (0.6%) were also observed. Cysts were the most common finding (19.2%), and duct dilation was frequent (7.1%). The significance of these findings in relation to fertility is considered.  相似文献   
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Vitrification has been the method of choice for the cryopreservation of bovine oocytes, as rapid cooling decreases chilling sensitivity. The aim of this study was to determine the in vitro and in vivo survival and the viability of immature oocytes vitrified using super‐cooled liquid nitrogen. Immature oocytes were randomly allocated to three groups: (i) non‐vitrified control group, (ii) vitrified in normal (?196°C) liquid nitrogen (LN2) and (iii) vitrified in super‐cooled LN2 (≤?200°C). Open‐pulled glass micropipettes were used as vitrification containers. Immature oocytes were in vitro‐matured, fertilized and cultured to the blastocyst stage. In vitro viability was assessed by cleavage and blastocyst rates on days 2 and 7 of culture respectively. Vitrified blastocysts derived from the immature vitrified oocytes were directly transferred to synchronous recipients. The in vitro embryo development of vitrified immature oocytes was not influenced by the LN2 state. After direct transfer (one embryo per recipient) of 16 embryos obtained from immature vitrified oocytes (eight from each vitrified group), two healthy calves were born in each group. These results indicated that vitrification of immature bovine oocytes using glass micropipettes under normal or super‐cooled LN2, resulted in viable blastocysts and live calves following in vitro embryo production.  相似文献   
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Serum concentrations of relaxin and progesterone were measured by specific radioimmunoassays in pregnant, pseudopregnant, or ovariectomized (between gestation weeks 4 and 5) pregnant Labrador Retriever bitches. Daily administration of 17 alpha-ethyl-19-nortestosterone was performed to maintain gestation in the ovariectomized pregnant bitches. This synthetic gestagen was selected because it did not interfere with the assay for endogenously secreted progesterone concentration in serum. Serum progesterone concentration was high in ovarian-intact pregnant or pseudopregnant bitches, but the mean progesterone concentration in pseudopregnant bitches (evaluated at 4 weeks after mating) was only 56% of the concentration in pregnant bitches. After ovariectomy, serum progesterone concentration decreased to undetectable values. Unlike progesterone, serum relaxin concentration increased during the latter half of pregnancy in the ovarian-intact and in the ovariectomized pregnant bitches, but relaxin was not detectable at any time in the pseudopregnant bitches. The amount of relaxin measured in the ovariectomized pregnant bitches was less (P less than 0.05) than that in ovarian-intact bitches, suggesting that the ovaries may have contributed to the total circulating relaxin concentration in the latter. Placental production of relaxin might have accounted for the serum relaxin concentration after ovariectomy; thus, the ovary and placenta each may secrete relaxin during gestation in bitches. Regardless of its source, measurement of serum relaxin concentration may offer a useful way of distinction between pregnancy and pseudopregnancy in dogs.  相似文献   
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