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81.
A cross-sectional survey was conducted in Sudan to determine sero-prevalence and risk factors associated with Neospora caninum infection in non-vaccinated dairy herds and to assess importance of the disease. Blood samples were collected from a total of 262 animals from 25 herds. Sera were tested for antibodies against N. caninum using ELISA test. The prevalence rates of N. caninum antibodies in cattle were high both at herd level (44%) and at individual animal level (10.7%). Herd level infection rates were similar in Khartoum State (43.7%) and at Gazira States (44.4%). The overall prevalence rates were higher (16.1%) in Gazira State than in Khartoum State (9%) but with no significant variation. The sero-prevalence at individual animal level was significantly higher (p < 0.05) in animals with history of abortion (12.8%) than in apparently healthy animal (11.3%), animal with history of infertility (8.1%), or neonatal death of calves (4.3%). In addition, significantly higher (P < 0.05) sero-prevalence was observed in samples collected during the rainy season (6.87%) than winter (3.05%) or summer (0.76%). However, no significant differences in sero-prevalence due to locality, animal breed, sex, and age were observed (p > 0.05). This preliminary study reveals for the first time the existence of natural N. caninum infection in Sudan. Also, the findings of the present study indicated that this disease is highly prevalent in two major areas of dairy production in the country, and this calls for control strategy to be implemented.  相似文献   
82.
The morpho-physiological quality of seedlings is negatively affected by the wide scale use of forest soils as substrates in developing countries. With the objective of finding long-term sustainable supply of growing media, compost was produced from shredded branches of three fast growing species (Acacia cyanophylla (AA), Acacia cyclops (AS) and Eucalyptus gomphocephala (EG). The composting process covered three different periods over the course of a year. Pile temperatures were monitored daily and the composts were routinely sampled and analyzed for 19 chemical variables. Although composting is feasible year-round in arid climates, compost produced in the humid cool conditions of autumn, winter and early spring reaches the maturation phase more quickly than compost produced under hot, dry summer conditions. It also requires less turning and water. The evolution of the composting process and quality of the final product can be assessed using three chemical variables (C/N, pH, EC). Seed germination rates in the three types of compost were similar to that in a peat:vermiculite substrate and vigorous high quality seedlings were produced in the two acacia composts. However, compost-grown seedlings had significantly smaller shoots and root systems than those produced in peat substrate. Principal components analyses showed that the quality of a compost-based substrate is reproducible and that its final chemical composition can be predicted from its raw organic materials. The EG composts had higher pH than the acacia composts, whereas the AA and EG composts were higher in mineral salts than the AS.  相似文献   
83.
We evaluated the effects of dietary supplementation with different preparations of probiotics on the performance of broiler chickens experimentally infected with 2 × 10(4) sporulated oocysts of Eimeria tenella at 14 days of age. Three hundred, day-old, Cobb-500 chicks, as hatched, were separated into 10 equal groups with three replicates. Two of the groups, one challenged with E. tenella oocysts and the other not, were given a basal diet and served as controls without medication. The other challenged groups were given the anticoccidial lasalocid (60 mg/kg) or Enterococcus faecium (5 × 10(8) or 5 × 10(9)cfu/kg feed), Bifidobacterium animalis (5 × 10(8)cfu/kg feed), Lactobacillus reuteri (5 × 10(8)cfu/kg feed), Bacillus subtilis (5 × 10(8)cfu/kg feed), or a multi-species probiotic mix at 5 × 10(8) or 5 × 10(9)cfu/kg feed, respectively. The trial lasted 6 weeks. Individual body weight, feed intake per pen and feed conversion ratio values were recorded weekly, along with the extent of bloody diarrhea, excreta oocyst numbers and bird mortality. Caecal lesions were assessed and intestinal samples were taken for histopathological and bacteriological evaluation from ileum and caecum. Overall growth performance of chickens fed the multi-species probiotic mix at both levels was higher (P<0.05) compared to the infected control. Overall oocyst shedding was lowest (P<0.05) in the lasalocid supplemented group. Villous height was higher (P<0.05) in Bacillus supplemented groups compared to infected controls. The Lactobacillus supplemented group had the highest (P<0.05) numbers of both Lactobacillus and Bifidobacterium in ileum and caecum. In conclusion, dietary probiotics are promising for further investigation on improving intestinal health and growth performance of broiler chickens experimentally challenged with E. tenella.  相似文献   
84.
Because of an apparent sexual ambiguity (enlarged clitoris), a 1-year-old mongrel dog was presented to the clinic. A positive result on a GnRH stimulation test revealed the existence of functional testicular tissue. A midline laparotomy was performed, and gonads resembling testes were resected along with the adherent parts of the uterine horns. Microscopic examination confirmed that the sampled gonads were testes. Cross-sections of the head and tail of the epididymis revealed their typical structures. All layers of the uterine wall were well-developed. The lumen was stellar, covered by columnar cylindrical epithelium, although locally some epithelial cells had changed in height from columnar to flat. The uterine glands were distributed in functional layer of endometrium in a non-uniform way. Cytogenetic analysis based on the evaluation of metaphase plates of blood lymphocytes showed a female karyotype, 78,XX. PCR amplification of the SRY gene was negative in the studied mongrel dog. This canine disorder may be genetically heterogeneous, potentially with a different mutation in different breeds. An autosomal recessive inheritance for the XX male is suggested in such cases. The present case of sex reversal syndrome concerns a non-purebred dog. In mongrels, it is definitely less likely for the defect to be inherited because of a recessive disorder. According to the recently proposed nomenclature, the described case should be classified as 78,XX testicular DSD syndrome.  相似文献   
85.
In both the horse and the man, nutritional ergogenic aids have been used to improve physical ability in conjunction with an appropriate training regimen. Although training increases physical condition, the ease of taking a nutritional additive to improve training results explains the demand for supplementation, which may increase mechanical energy of work, delay onset of fatigue, or improve neuromuscular coordination. The purpose of this study was to determine the effects of oral supplementation of β-hydroxy-β-methylbutyrate (HMB) and γ-oryzanol (GO) on indices of exercise-induced muscle damage in Thoroughbred race horses. In this 32-week study, the horses were assigned to either a placebo, GO (3.0 g/d), HMB (15 g/d), or GO and HMB treatment groups. The supplements were administered for the first 16 weeks of the study during the training period before the racing season began. Blood samples were taken at baseline, and then during training, before exercise, immediately after exercise, and 30 minutes after exercise. Heart rate and speed were monitored in each exercise session. Hematocrit, glucose, lactate (LA), creatine phosphokinase, and aspartate aminotransferase were measured before and after each exercise session. Analysis of variance showed a significantly greater increase in postexercise creatine kinase activity in placebo-supplemented group than in the other treatment groups, both in the training period and during the racing seasons (P < .05). Blood LA was higher immediately after exercise in the placebo group compared with the supplemented groups. In conclusion, supplementation with HMB and GO resulted in decreased creatine kinase and LA after exercise. These findings support the hypothesis that HMB and GO supplementation helps to prevent exercise-induced muscle damage.  相似文献   
86.
Bee pollen (BP) is one of the most useful therapeutic products favoured by natural medicine scientists because of its possible nutritional and medical applications. It exhibits many impacts such as antimicrobial, immunostimulating, antioxidants and hepatoprotective. Furthermore, BP has some useful therapeutic features in numerous pathological situations such as its impact to normalize wound healing. Based on previous literatures, the level of BP supplement in livestock and poultry ranged from 0.1 to 20 g/kg diet. This variation depends on the species, physiological status, age and purpose of addition; so far generally, it accepted to use the level with no side effects. It has been observed that BP enhanced growth performance, immunity responses and blood variables and had hypoglycaemic activity by reducing the lipid in the blood and carcass. Also, BP contains more nutrients, which stimulate faster differentiation and proliferation of the cells of immune system of birds. Therefore, the present review recommends that BP supplementation (up to 20 g/kg diet) had possible beneficial impacts, antioxidants and protective activities on most of the production, productive and health patterns of livestock.  相似文献   
87.
Bovine tuberculosis (BTB) is a widespread zoonosis in developing countries but has received little attention in many sub-Saharan African countries including Sudan and particularly in some parts such as Darfur states. This study aimed to detect bovine tuberculosis among caseous materials of cattle slaughtered in abattoirs in South Darfur State, Sudan by using microscopic and PCR-based methods. The study was a cross-sectional abattoir-based study which examined a total of 6,680 bovine carcasses for caseous lesions in South Darfur State between 2007 and 2009. Collected specimens were examined for the presence of acid-fast bacilli (AFB) by using microscopic and culture techniques. Isolated mycobacteria were identified by selected conventional cultural and biochemical tests in comparison to a single tube multiplex PCR (m-PCR) assay which detect Mycobacterium bovis-specific 168-bp amplicons. Of the total 6,680 slaughtered cattle examined in South Darfur, 400 (6 %) showed caseations restricted to lymph nodes (86.8 %) or generalized (13.2 %). Bovine tuberculosis was diagnosed in 12 (0.18 %), bovine farcy in 59 (0.88 %), unidentified mycobacteria in 6 (0.09 %), and missed or contaminated cultures in 7 (0.1 %). Out of 18 cultures with nonbranching acid-fast rods, 12 amplified unique 168-bp sequence specific for M. bovis and subsequently confirmed as M. bovis. With the exception of the reference M. tuberculosis strains, none of the remaining AFB amplified the 337-bp amplicon specific for M. tuberculosis. It could be concluded that bovine tuberculosis is prevalent among cattle in South Darfur representing 4.5 % from all slaughtered cattle with caseous lesions. The study sustains microscopy as a useful and accessible technique for detecting AFB. m-PCR assay proved to be valuable for confirmation of BTB and its differentiation from other related mycobacteriosis, notably bovine farcy.  相似文献   
88.
Ten Nubian goats were given oral doses of the fresh fruits and leaves of Cassia senna at 1, 5, and 10 g / kg /day. Eight goats died within 30 days and two others were slaughtered in a moribund condition on days 18 and 29. The clinical signs of diarrhoea, inappetence, loss of condition, and dyspnoea were well correlated with the pathological findings. There was an increase in G.O.T., ammonia, urea, and total cholesterol and a decrease in total protein in the serum of Cassia‐poisoned goats. Blood sugar level was reduced and the increase in the values of Hb, PCV, and RBC was due to haemoconcentration.  相似文献   
89.
Journal of Soils and Sediments - The objective of this study was to evaluate the mutual relations between the soil organic matter (SOM) fractions: fulvic acids (FA), humic acids (HA), humins (HN),...  相似文献   
90.
Organic wastes can be usefully recovered to produce organic amendments, for example, compost, to be used for crop production, thus reducing impacts through efficient waste management. The aim of this work was to study the effects of compost obtained from municipal waste in combination with poultry manure on plant growth, nitrate reductase (NR) activity and absorption and distribution of heavy metals (HM) in plant tissues of tomatoes, grown in pots in greenhouses. Two compost types obtained from municipal waste mixed with poultry manure (C1?=?3:2 and C2?=?2:3) were used at two different ages (105 d and 173 d) and at two mix rates with soil (32.5?g pot?1 and 65?g pot?1); soil with no compost amendment was used as control. The experiment was conducted using tomato plants in pots and plant growth and nutrient plant uptake was determined after 65?days from plant transplanting. Results obtained indicated that compost type and compost rate affected biomass production. However, compost age did not influence the development of plants. Nutrient status of tomato plants was also investigated with reference to the N cycle. Nitrite accumulation in the leaves increased with the increase in compost doses. The accumulation of NO2? was associated with a significant increase in NR activity. HM content in leaves decreased with compost use. HM accumulated preferentially in roots and leaves and the soil to root metals transfer was in this order: Fe (1.08–2.14)> Co (0.53–4.10)>Cu (0.28–2.28) >Mn (0.3–1.34) >Zn (0.87–1.21)>Cr (0.12–1.64). The highest and lowest dynamic bioaccumulation factors (BAFdyn) were observed in roots and stems, respectively. The root system acted as a barrier for Cd and Pb. It was concluded that compost use is beneficial for tomato plants, with particular reference to the compost obtained by using a higher amount of poultry manure (C2) in the mix.  相似文献   
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