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1.
This study tested the hypotheses that: (1) either acute stress induced by Burdizzo castration, or cortisol infusion would modulate plasma glucose, insulin and growth hormone (GH) concentrations; and (2) immune modulation induced by cortisol would be dependent on the pattern, intensity and duration of circulating cortisol concentrations. Fifty 9.2-month-old Holstein×Friesian bulls (232±2.0 kg) were blocked by weight and randomly assigned to one of five treatments (n=10 per treatment): (1) sham handled control; (2) Burdizzo castration; (3) hydrocortisone infusion to mimic the castration-induced secretion pattern of cortisol; (4) hourly pulse infusion of hydrocortisone; and (5) sustained infusion of hydrocortisone for 8 h. Blood samples were collected intensively on day 0, and weekly from days 1 to 35. Castration acutely increased plasma cortisol, GH and haptoglobin concentrations, suppressed lymphocyte in vitro interferon-γ (IFN-γ) production, but had no effect on plasma glucose and insulin concentrations. Cortisol infusion to simulate the castration-induced secretion pattern of cortisol, and pulse infusion of cortisol did not suppress the IFN-γ production. A sustained infusion of cortisol resulted in the transient suppression of IFN-γ production. Moreover, the sustained cortisol infusion resulted in increased plasma glucose, insulin and GH concentrations. The overall 14-day feed intakes and 35-day growth rates were not affected by treatments. In conclusion, cortisol infusion to induce immune suppression in vivo occurred only at pharmacological doses. Within physiological ranges, cortisol was not associated with the suppression of immune function, indicating that during castration cortisol per se is not responsible for the suppression of in vitro IFN-γ production.  相似文献   
2.
The objective was to assess the effect of banding or burdizzo castration performed on farms on plasma testosterone, acute-phase proteins, scrotal circumferences, growth, and well-being of bulls. 243 Continental bulls (12 months; 399.2 ± 5.72 kg) from three different farms were allocated at random, after stratification on weight within breed type, to one of three treatment groups: banding castration (BAND; n = 80), burdizzo castration (BURD; n = 83), or controls (CON; n = 80). The castration methods were conducted under local anaesthesia, and tetanus toxoid vaccine and antibiotic were also injected at castration. BAND and BURD castrates had lower (P < 0.001) plasma testosterone concentration than control bulls, with no difference between BAND and BURD castrates on 28 d post-castration. From days 0 to 14 post-castration, BAND (P = 0.0002) and BURD (P < 0.0001) castrates had lower average daily gain (ADG) than CON bulls, no difference (P = 0.46) was found between BAND and BURD castrates. From days 15 to 28, BAND castrates had lower ADG compared with BURD castrates (P = 0.03) and CON bulls (P = 0.01), while no difference (P = 0.76) was found between BURD and CON. From days 29 to 56, BAND (P = 0.01) and BURD (P = 0.002) castrates had lower ADG than CON bulls, no difference (P = 0.55) was found between BAND and BURD. From days 57 to 84, the ADG of BAND castrates was not different compared with BURD castrates (P = 0.12) and CON bulls (P = 0.38), while BURD had lower (P = 0.02) ADG compared with CON. The integrated ADG from day 0 to 112 of BAND (P = 0.0001) and BURD (P = 0.02) groups were lower compared with CON, while there was no difference (P = 0.09) between BAND and BURD castrates. On d 14 post-castration, BAND castrates had lower scrotal temperature than BURD (P < 0.0001) and CON (P < 0.0001), and BURD castrates had greater (P < 0.006) scrotal temperature than CON; BAND castrates had lower scrotal latitudinal and longitudinal circumferences than BURD castrates (P < 0.001) and CON bulls (P < 0.001), and BURD castrates had greater (P < 0.001) scrotal latitudinal and longitudinal circumferences than CON bulls. BAND (P < 0.0001) and BURD (P = 0.01) castrates had greater glucose concentration than CON bulls, and BAND castrates had greater (P = 0.04) glucose concentration than BURD. In conclusion, BAND or BURD castration significantly reduced plasma testosterone concentration; reduced average daily weight gain mainly during the first 2 weeks, which was not compensated during the subsequent 16 weeks; increased withdrawal of stored energy and increased plasma protein concentration. BURD showed an advantage over BAND in growth during days 15 to 28 following castration.  相似文献   
3.
Calfhood diseases have a major impact on the economic viability of cattle operations. A three part review series has been developed focusing on calf health from birth to weaning. In this paper, the last of the three part series, we review disease prevention and management with particular reference to pneumonia, focusing primarily on the pre-weaned calf. Pneumonia in recently weaned suckler calves is also considered, where the key risk factors are related to the time of weaning. Weaning of the suckler calf is often combined with additional stressors including a change in nutrition, environmental change, transport and painful husbandry procedures (castration, dehorning). The reduction of the cumulative effects of these multiple stressors around the time of weaning together with vaccination programmes (preconditioning) can reduce subsequent morbidity and mortality in the feedlot. In most studies, calves housed individually and calves housed outdoors with shelter, are associated with decreased risk of disease. Even though it poses greater management challenges, successful group housing of calves is possible. Special emphasis should be given to equal age groups and to keeping groups stable once they are formed. The management of pneumonia in calves is reliant on a sound understanding of aetiology, relevant risk factors, and of effective approaches to diagnosis and treatment. Early signs of pneumonia include increased respiratory rate and fever, followed by depression. The single most important factor determining the success of therapy in calves with pneumonia is early onset of treatment, and subsequent adequate duration of treatment. The efficacy and economical viability of vaccination against respiratory disease in calves remains unclear.  相似文献   
4.
Extract

Most outbreaks of parasitic gastro-enteritis in sheep in New Zealand have been ascribed to the presence of nematodes of the family Trichostrongylidae, and in particular the genera, Haemonchus, Ostertagia, and Trichostrongylus. However, during the period 1956–58, a number of outbreaks of disease occurred in lambs and the condition was associated with heavy Neniatodirus infestation. Although Neinatodirus spp. are commonly foundin sheep in this country, only moderate numbers of worms are usually present in any individual and the worm has been regarded as non-pathogenic. Similar views were held in the British Isles until about 1951, when an acute disease condition of lambs, associated with heavy Neniatodirus burdens, caused serious losses.  相似文献   
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6.
六盘水市地处贵州西部的乌蒙山区,农户养鸡多以家庭分散放养为主。农户养鸡规模小,资金缺乏,技术和科学养殖观念淡漠,养鸡效益不高,给农户带来的实惠不多。在农户中开展鸡阉割技术培训,进行特色化养殖,提高本地土鸡品质,改良口感,提高售价。这样才能让农户增收,并提高农户养鸡的积极性。  相似文献   
7.
利用免疫组化SP法检测去势及补充雄激素后大鼠垂体中雄激素受体(Androgen Receptor,AR)蛋 白的表达,以探讨雄激素对垂体的作用机制。结果表明:去睾丸组(GM组)大鼠垂体AR减少;去睾丸并 补充雄激素组(GM T组)大鼠AR表达恢复到接近正常水平。说明去睾丸大鼠由于缺乏内源性雄激素 引起垂体AR表达减少;而补充外源性雄激素可缓解或抑制这一变化。  相似文献   
8.
[目的]为了避免公猪因含雄性激素、有难闻的膻气味而影响肉的品质,同时能够充分发挥小公猪生长发育快的潜力。[方法]以杜洛克、长白、约克夏三元杂交商品猪为研究对象,进行哺乳公猪最适去势日龄研究。[结果]结果表明,杜洛克、长白和约克夏三元杂交哺乳公猪于14日龄去势,28日龄断奶时增重最大,与其他日龄去势相比,增重效果显著(P<0.05)。[结论]推行早期断奶可提高母猪的年产仔窝数,对于饲养瘦肉型三元杂生长肥育猪的生产场,14日龄对哺乳公猪进行去势,既可以充分发挥小公猪生长发育快的潜力,又符合当前规模化猪场推行哺乳仔猪早期断奶的需要,是值得推广应用的技术。  相似文献   
9.
The location of an undescended testicle influences the choice of surgical technique for efficient cryptorchid castration. We review a standardized protocol for preoperative examination to dictate surgical approach to cryptorchidism. Cases are split into two periods: 2004–2006 and 2007–2014. In 2004–2006, conventional cryptorchidectomy and laparoscopic cryptorchid castration (standing) were both offered, but the choice of technique was based primarily on owners' preference for a recumbent or standing procedure. In 2007–2014, ultrasonography was used to locate the testes and dictate the preferred surgical approach; for abdominal testes, laparoscopic intraabdominal spermatic cord ligation without orchidectomy was preferred and for inguinal testes, conventional open orchidectomy. The numbers of animals requiring a second procedure to complete castration were compared between the two periods. In addition, failure rates for individual testes grouped by location were determined separately for the different techniques, and the value of preoperative ultrasonography to locate the retained testes was assessed. In 2004–2006, 15.3% (20/131) of the cryptorchids needed more than one surgery to complete castration, compared to 0.7% (1/144) in 2007–2014. Failure rates for laparoscopic castration were 0/168 (0%) for abdominal, 3/40 (7.5%) for inguinal, and 9/55 (16.4%) for scrotal testes; for conventional castration, failure was recorded for 3/12 (25%) abdominal and 0/92 (0%) inguinal testes. For 94% (156/166) of retained testes, ultrasound-based preoperative advice on surgical approach was correct. Using a standardized preoperative examination to determine choice of surgical technique significantly (P < .001) reduced the number of second surgeries needed to complete castration. Preoperative ultrasound is therefore a useful aid to determining the surgical approach to cryptorchid castration.  相似文献   
10.
This study aimed to characterise current practice relating to equine castration in the UK. A questionnaire was posted to all 655 veterinary practices specified to provide veterinary care for horses, or classified as specialist equine practices. Respondents were asked to cite the number of equine castrations performed annually by the practice, describe techniques used for castration, outline anaesthetic/sedative/analgesic drug protocols used and provide details of post-operative medication. There was a 43% response rate to the questionnaire. Considerable variation in techniques and analgesia provision was identified, with the majority of respondents using a number of sedation/anaesthetic protocols rather than a single technique. This characterisation of current practice provides a useful platform from which subsequent investigations into welfare implications of current equine castration techniques can be directed.  相似文献   
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