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131.
A female boa (Boa constrictor) from a zoological collection was submitted for necropsy after sudden death. Prominent pathological findings included a diphtheroid colitis, endoparasitism, focal pneumonia and inclusion bodies typical for inclusion body disease (IBD). In the colon entamoebae were identified, which differed in size and distribution from Entamoeba invadens. Gene sequence analysis of the 18S ribosomal RNA revealed 100% similarity with an Entamoeba species from the African bullfrog (Pyxicephalus adspersus), probably Entamoeba ranarum. The snake was possibly immunosuppressed, and the source of infection remains unclear. This is the first report of an infection with an amphibian Entamoeba species associated with colitis in a snake.  相似文献   
132.
Congenital defects like myofibrillar dysplasia (splayleg), umbilical and inguinal hernias, cryptorchism, intersexes, and anal atresia occur relatively frequently in swine. On the other hand, some developmental anomalies like double monsters are very rare. The present paper reports a rare case of a congenital complex malformation including polymelia, duplicitas coli partialis et recti, atresia ani et fistula rectogenitalis, duplicitas corpori uteri, cervicis, vaginae et vulvae and duplicitas vesicae, urethrae et renalis. A plausible interpretation concerning the etiology is that the anomalies arose from unequal partial twinning. The pig has been healthy and inconspicuous. Although no anus was formed defecation took place via a fistula to one of the vaginas. Posture and behaviour of the pig were normal. Cytogenetic analysis of blood lymphocytes revealed no numerical or gross structural anomalies. There have been no further piglets with developmental disorders in the same litter, in a second litter of the same parents and in other twelve litters by the same boar.  相似文献   
133.
本综述对猪生物医学模型的多样性和基因组学在这些模型持续开发中的重要性作了一个简要的更新。由于猪在体型大小、生理条件、器官发育和疾病发展等方面与人类相似,因而已作为一种重要的哺乳动物医学模型为人类所用。将猪作为人类医学模型,可以使研究人员从容不迫地安排研究时间,并可利用普通的人类医学技术对机体内部的血管和器官进行成像处理,且可以采集重复的外周样本,并且在扑杀后可采集复杂的粘膜组织样本。以猪为医学模型,能够利用同窝的猪或克隆猪和转基因猪,因而使比较分析和遗传作图更为容易。以猪作为人类医学的动物模型可获得大量代表各种组织的分化方向明确的细胞系,从而可更加有利于基因表达和药物敏感性的检测。因此,对人而言,猪是一种出色的生物医学模型。由于猪在基因序列和染色体结构上与人类高度同源,因而对基因组应用而言,其不失为一个宝贵的资源。由于目前猪基因组序列已被人类充分掌握,因而有改良型遗传学方法和蛋白质组学方法可供这些比较分析方法所利用。本综述将论述用于探测这些模型的基因组学方法中的某些方法,并将重点介绍黑色素瘤和抗传染性疾病的基因组学研究情况,论述在设计此类研究时应予以考虑的问题。本文最后将对利用基因组学方法开发控制具有最高经济价值的猪病—猪繁殖与呼吸综合征病毒(Porcine Reproductive and Respiratory Syndrome,PRRSV)—新型替代方法的可行性、和将从PRRSV研究中获得的知识应用到人传染性疾病研究中的可行性作简短讨论。  相似文献   
134.
In vitro fertilization (IVF) of in vitro matured (IVM) oocytes in pigs has become the most popular method of studying gametogenesis and embryogenesis in this species. Furthermore, because of recent advances in in vitro culture (IVC) of IVM–IVF embryos, in vitro production (IVP) of embryos now enables us to generate viable embryos as successfully as for in vivo -derived embryos and with less cost and in less time. These technologies contribute not only to developments in reproductive physiology and agriculture but also to the conservation of porcine genetic resources and the production of cloned or genetically modified pigs. However, in IVP, there still remains the problem of abnormal ploidy, which is caused by performing procedures under non-physiological conditions. In recent years, unique technologies such as intracytoplasmic sperm injection (ICSI) or xenografting of gonadal tissue into immunodeficient experimental animals have been developed to help conserve gamete resources. These technologies combined with IVP are expected to be useful for the conservation of gametes from important genetic resources. Here, we discuss the developmental ability and normality of porcine IVP embryos and also the utilization of ICSI and xenografting in advancing biotechnology in pigs.  相似文献   
135.
Background: The endocrine diagnosis of primary hyperaldosteronism in cats currently is based on an increased plasma aldosterone to renin ratio, which has several disadvantages for use in veterinary practice. Objectives: To establish a reference range for the urinary aldosterone to creatinine ratio (UACR) and to determine whether oral administration of either sodium chloride or fludrocortisone acetate is effective for use in a suppression test. Animals: Forty‐two healthy cats from an animal shelter and 1 cat with primary hyperaldosteronism from a veterinary teaching hospital. Methods: Morning urine samples for determination of the basal UACR were collected from 42 healthy cats. For the suppression tests, urine samples for the UACR were collected after twice daily oral administration for 4 consecutive days of either sodium chloride, 0.25 g/kg body weight (n = 22) or fludrocortisone acetate, 0.05 mg/kg body weight (n = 15). Results: The median basal UACR was 7.2 × 10?9 (range, 1.8–52.3 × 10?9), with a calculated reference range of <46.5 × 10?9. Administration of sodium chloride resulted in adequate salt loading in 10 of 22 cats, but without significant reduction in the UACR. Administration of fludrocortisone resulted in a significant decrease in the UACR (median, 78%; range, 44–97%; P < .001) in healthy cats. In the cat with an aldosterone‐producing adrenocortical carcinoma, the basal UACR and the UACR after fludrocortisone administration were 32 × 10?9 and 36 × 10?9, respectively. Conclusions and Clinical Importance: Using the UACR for an oral fludrocortisone suppression test may be useful for the diagnosis of primary hyperaldosteronism in cats.  相似文献   
136.
1. Naked oats belong to the same species as 'common oats', Avena sativa, but have a non-lignified husk which readily becomes detached during harvesting. The absence of the indigestible husk can be predicted to give an increased metabolisable energy (ME) content for poultry. 2. Measurements of true metabolisable energy (TME(N)) were performed on 3-week-old broiler chicks (Cobb males), adult cockerels (ISA Brown, greater than one year old) and 7-week-old turkeys (BUT T8 males). The measurements were repeated in 2000, 2001 and 2002, with some measurements on a subset of varieties in 2004. 3. High-oil naked oat lines yielded 12% more energy (TME(N)) than wheat. Naked oats, excluding the experimental high-oil lines, yielded 8.5% more energy than simultaneously assayed wheat samples. 4. In samples from the 2004 harvest, conventional oats gave TME(N) values about 13% lower than those of wheat. 5. The addition of beta-glucanase produced an increase of about 4% in the apparent metabolisable energy (AME) of oats for broiler chickens. This effect was associated with a 70% decrease in the jejunal viscosity of broilers receiving a 500 g/kg naked-oat diet. 6. The oil content of naked oats was about 5 times greater than that of wheat, with the high-oil lines rising to more than 6 times greater. Naked oats had a lower starch content than wheat but not sufficiently lower to negate the energy benefits of the higher oil content. The crude protein (CP) contents of naked oats were similar to those of wheat, with the high-oil varieties tending to be higher in CP also.  相似文献   
137.
Plague is a rare but often fatal zoonosis endemic to the western United States. Previous studies have identified contact with pets as a potential risk factor for infection. We conducted a matched case-control study to better define the risks associated with pets at both the household and individual levels. Using a written questionnaire, we surveyed nine surviving plague patients, 12 household members of these patients, and 30 age- and neighbourhood-matched controls about household and individual exposures. Overall, 79% of households had at least one dog, 59% had at least one cat and 33% used flea control, with no significant differences between case and control households. Four (44%) case households reported having a sick dog versus no (0%) control households [matched odds ratio, (mOR) 18.5, 95% confidence interval (CI) 2.3-infinity], and four (44%) patients reported sleeping in the same bed with a pet dog versus three (10%) controls (mOR 5.7, 95% CI 1.0-31.6). Within case households with multiple members, two (40%) of five patients slept with their dogs versus none (0%) of 12 healthy family members (P=0.13). The exposures to cats were not significant. Sleeping in the same bed as a pet dog remained significantly associated with infection in a multivariate logistic regression model (P=0.046). Our findings suggest that dogs may facilitate the transfer of fleas into the home and that activities with close extended contacts with dogs may increase the risk of plague infection.  相似文献   
138.
Background: When an animal is exposed to a stressor, metabolic rate, energy consumption and utilisation increase primarily through activation of the hypothalamic-pituitary-adrenal(HPA) axis. Changes to partitioning of energy by an animal are likely to influence the efficiency with which it is utilised. Therefore, this study aimed to determine the physiological stress response to an exogenous adrenocorticotropic hormone(ACTH) challenge in beef heifers divergently ranked on phenotypic residual feed intake(RFI).Results: Data were collected on 34 Simmental weaning beef heifers the progeny of a well characterized and divergently bred RFI suckler beef herd. Residual feed intake was determined on each animal during the postweaning stage over a 91-day feed intake measurement period during which they were individually offered adlibitum grass silage and 2 kg of concentrate per head once daily. The 12 highest [0.34 kg DM/d] and 12 lowest[-0.48 kg DM/d] ranking animals on RFI were selected for use in this study. For the physiological stress challenge heifers(mean age 605 ± 13 d; mean BW 518 ± 31.4 kg) were fitted aseptically with indwelling jugular catheters to facilitate intensive blood collection. The response of the adrenal cortex to a standardised dose of ACTH(1.98 IU/kg metabolic BW~(0.75)) was examined. Serial blood samples were analysed for plasma cortisol, ACTH and haematology variables. Heifers differing in RFI did not differ(P = 0.59) in ACTH concentrations. Concentration of ACTH peaked(P 0.001) in both RFI groups at 20 min post-ACTH administration, following which concentration declined to baseline levels by 150 min. Similarly, cortisol systemic profile peaked at 60 min and concentrations remained continuously elevated for 150 min. A RFI × time interaction was detected for cortisol concentrations(P = 0.06) with high RFI heifers had a greater cortisol response than Low RFI from 40 min to 150 min relative to ACTH administration. Cortisol response was positively associated with RFI status(r = 0.32; P 0.01). No effect of RFI was evident for neutrophil, lymphocytes, monocyte, eosinophils and basophil count. Plasma red blood cell number(6.07 vs. 6.23; P = 0.02) and hematocrit percentage(23.2 vs. 24.5; P = 0.02) were greater for low than high RFI animals.Conclusions: Evidence is provided that feed efficiency is associated with HPA axis function and susceptibility to stress, and responsiveness of the HPA axis is likely to contribute to appreciable variation in the efficiency feed utilisation of cattle.  相似文献   
139.
奶牛产犊前后间隔的六周过渡期是一个非常关键的时段。此阶段不好的饲养管理会造成产奶量下降、繁殖效率的低下和增加代谢疾病等一系列问题,这不仅增加每千克牛奶的饲料成本而且也会降低牧场的整体营业收入。对于一个奶牛场而言,为了实现生产利润最大化就必须要求营养师、兽医师和牧场管理者达成共识,紧密配合共同来制定一个可行的饲养管理策略,以便帮助奶牛平稳地渡过产犊前后这个关键时期,以最大限度地发挥出奶牛的生产性能。  相似文献   
140.

Background

Antioxidant depletion and lipid peroxidation have been correlated with disease severity and associated with poor outcomes.

Hypothesis/Objectives

Supplementing dogs with N‐acetylcysteine (NAC) during the first 48 hours of hospitalization will increase cysteine, normalize glutathione concentrations, and decrease the degree of lipid peroxidation associated with illness.

Animals

Sixty systemically ill hospitalized client‐owned dogs and 14 healthy control dogs.

Methods

Randomized investigator‐blinded, placebo‐controlled prospective study. Dogs were randomized to treatment with NAC (n = 30) versus placebo (n = 30). Antioxidants, urine 8‐isoprostane/creatinine (IP/Cr), and clinical score were determined before and after treatment with NAC. Glutathione, cysteine, and vitamin E concentrations were quantified using high‐performance liquid chromatography. Atomic absorption spectroscopy and enzyme‐linked immunosorbent assays were used to quantify selenium and isoprostane concentrations, respectively.

Results

Ill dogs had significantly lower vitamin E concentrations (27 versus 55 μg/mL; P = .0005) as well as elevated IP/Cr ratios (872 versus 399 pg/mg; P = .0007) versus healthy dogs. NAC supplementation significantly increased plasma cysteine (8.67 versus 15.1 μM; P < .0001) while maintaining glutathione concentrations. Dogs in the placebo group experienced a statistically significant decrease in glutathione concentrations (1.49 versus 1.44 mM; P = .0463). Illness severity and survival were unchanged after short duration NAC supplementation.

Conclusions

Ill dogs experience systemic oxidative stress. Supplementation with NAC during the first 48 hours of hospitalization stabilized erythrocyte glutathione concentrations. The clinical impact of this supplementation and glutathione concentration stabilization was undetermined.  相似文献   
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