A survey of the Fish Fauna of Sudanese Irrigation Systems with Reference to the Use of Fishes in the Management of Ecological Problems (the Control of Aquatic Weeds, Malaria and Infective Schistosomiasis)

This paper reports on a fundamental study of the fish fauna already present within the irrigation canals. The fauna was investigated with a view to determining its use in the control of nuisance biota. Twenty-seven species of fish were collected, comprising 22 genera and 12 families. This fauna is closely allied to the fauna of the source water, the Blue Nile. Several Blue Nile species are absent and some of those collected are new recordings for the area. Each species of fish collected had neither a suitable feeding habit nor a wide enough distribution to have any significant effect on the levels of nuisance biota. This includes the mosquito fish. Gambusia affinis, which was specifically introduced for mosquito control. Improvement in the ecological conditions within the canals involves both the management of the already-existing fish stocks and the introduction and management of additional species. A reduction in the levels of aquatic weeds using phytophagous fishes should be a high priority with malacopliagous and larvivorous species also being introduced and their stocks managed. Species suitable for introduction, which are generally endemic to the Nile system, are suggested. The fish species diversity falls as the canals become smaller and the water within them subject to much greater variations in flow and quality. The lowest order canals (field canals) are probably unsuitable for permanent fish stocks. The nuisance biota within field canals can be controlled by simple improvements in crop-watering procedures. The widely distributed and diverse fauna found within minor canals suggests that problems due to fish-kills brought about by heavy pesticide and herbicide usage are not so severe as previously thought. The management of the ecological problems is a complex task due to the interrelationships of many factors.     

欧拉羊种公羊适应性观察与杂交改良乔科羊繁殖力分析

欧拉羊引入甘南州大水种畜场和碌曲县尕海乡、郎木寺镇等地改良乔科羊的肉用性能,引入的欧拉羊种公羊行为表现正常,抗寒、抗病能力较强,发病率为7％以下,死亡率在3％以下。繁殖性能和生长发育良好,主要生理生化指标都在正常范围之内。欧拉羊杂交改良乔科羊的繁殖力分析结果表明,用欧拉羊杂交改良乔科羊试验组的母羊受胎率、繁殖率、羔羊成活率及繁殖成活率均比当地乔科羊本交对照组分别提高1．45％、1．07％、4．06％和4．71％。     

欧拉羊与甘南山谷型藏羊杂交羔羊屠宰试验

通过对欧山F1和山谷型藏羊羔羊进行屠宰试验,结果得出:9月龄欧山F1羔羊宰前平均活重为38.25 kg,比本地山谷型藏羊羔羊宰前平均活重高10.17 kg,差异极显著(P<0.01)。欧山F1羔羊胴体重和屠宰率分别为15.14 kg和39.58%,比对照组高4.58 kg(P<0.01)和1.96个百分点,差异极显著。欧山F1羔羊净肉率、后腿比例和腰肉比例分别为29.65%、38.18%和12.99%,高于山谷型藏羊4.01、7.78和2.68个百分点;欧山F1羔羊GR值和眼肌面积分别为8.23 mm和12.74 cm2,高于山谷型藏羊1.48 mm和4.38 cm2。     

Gordon memorial lecture. The biologists' debt to the domestic fowl

Although it is highly desirable to reduce the need for experiments with animals, in vitro methods cannot entirely supplant them. Observations made in simple systems must be checked in a live subject if they are to be relevant to man or other higher animals. Young growing chicks are very susceptible to vitamin deficiencies. Biological assays in chicks have been used to check the validity of chemical and microbiological methods of measuring vitamins in foods. Experiments with chicks and chick embryos deprived of vitamin B12 have served to predict the likely clinical effects of analogues of the vitamin. The discovery of the growth-promoting properties of dietary antibiotics stimulated research into the influence of the gut microflora on its host. Studies in germ-free and gnotobiotic chicks have implicated Streptococcus faecium as one of the organisms responsible for the growth depression reversed by antibiotics. In general the growth of conventional chicks given adequate diets is slightly less good than that of their germ-free counterparts, although small beneficial effects of the microflora have been observed in special circumstances. The most important function of the indigenous microflora appears to be as a barrier against invasion by pathogens. To sustain this protective barrier may incur a small cost to the host in terms of dietary energy and other nutrients.     

The sensitivity and specificity of a modified ELISA for the diagnosis of Johne's disease from a field trial in cattle

An enzyme-linked immunosorbent assay (ELISA) for the detection of antibodies against Mycobacterium paratuberculosis in cattle was evaluated in three herds known to have Johne's disease. Prior to testing, the plasma was absorbed with dried Mycobacterium phlei in order to remove cross-reacting antibody specificities. The sensitivity and specificity of the ELISA were calculated after repeatedly testing 327 cattle in the infected herds. Of these, 53 animals had one or more positive faecal cultures or had post-mortem histopathological evidence of infection. The other 274 had three or more negative faecal culture results, and were regarded as non-infected for the purpose of evaluation of the ELISA. Using these criteria for the presence or absence of infection, the M. phlei-absorbed ELISA under field conditions had a 57% sensitivity and a 98.9% specificity. The sensitivity of the absorbed ELISA depended on the stage of disease of the animal under test. In general, it appeared that animals in the more advanced stages of disease were absorbed ELISA positive, whereas those in the early stages of infection were not detected. These results indicate that the M. phlei-absorbed ELISA has an important role as a test for the diagnosis and control of Johne's disease in cattle.     

Procarbazine as adjunctive therapy for treatment of dogs with presumptive antemortem diagnosis of granulomatous meningoencephalomyelitis: 21 cases (1998-2004)

BACKGROUND: Granulomatous meningoencephalomyelitis (GME) is an idiopathic inflammatory disease of the central nervous system. Remission often is short-lived in dogs treated with glucocorticoids. Procarbazine is T cell-specific and crosses the blood-brain barrier. HYPOTHESIS: Dogs with presumptive antemortem diagnosis of GME given procarbazine as adjunctive therapy to prednisone will have improved long-term outcome compared with dogs given no treatment or glucocorticoids alone. ANIMALS: Two groups were studied: (1) Dogs with presumptive antemortem diagnosis of GME treated with procarbazine and prednisone (n = 21); (2) Dogs that had a histologic diagnosis of GME at postmortem examination and received no treatment (n = 11). METHODS: Dogs with presumptive GME treated with procarbazine were identified retrospectively from medical records of 2 veterinary referral hospitals. Selection criteria required all dogs have a neurologic examination, blood work, cerebrospinal fluid analysis, and brain imaging (MRI or CT). RESULTS: Median survival time for all dogs studied was 5.0 months. Median survival time for dogs treated with procarbazine was 14.0 months and for untreated dogs, 0.73 months. Treatment with procarbazine was significantly correlated with survival time (P < .001). Procarbazine was the only independent predictor of survival. Prednisone was reduced in dosage or discontinued in 17 dogs. Adverse reactions to procarbazine therapy included myelosuppression in 7 dogs and hemorrhagic gastroenteritis in 3 dogs. CONCLUSION: These data suggest that procarbazine treatment of presumptive GME may result in greater improved long-term outcome than has been previously reported for glucocorticoid treatment alone and may complement other immunomodulatory therapies. Procarbazine-treated dogs must be monitored for adverse reactions.     

A Rare Case of Polyorchidism in a Cat with Four Intra‐abdominal Testes

Polyorchidism is a rare congenital anomaly defined as the presence of more than two histologically proven testes. We report a case of a 9‐month‐old European cat with four intra‐abdominal testes. The diagnosis was performed by means of ultrasonography, intra‐operative examination and histological confirmation. The case reported here presents an extremely rare anomaly, as no previous studies in veterinary medicine have reported the presence of four testes. This case suggests that supernumerary testes should be included as differential diagnoses for intra‐abdominal masses.     

半血野生盘羊与欧拉羊杂交F1代生长发育规律研究

本研究以半血野生盘羊和欧拉羊杂交F1代羊,即含1/4野生盘羊血统羊为素材,对含1/4野生盘羊血统羊生长发育规律进行了分析。结果表明:含1/4野生盘羊血统羊早期生长发育快,体重与体尺间呈极显著的正相关(P0.01),体尺与体重的最优回归方程Y=-37.758+0.431X3+0.529X1,R2=0.962。