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31.
This study was carried out to assess the prevalence of mange in sheep and goats in five local government areas (LGAs) of Ogun State in South Western Nigeria. A total of 4,973 sheep and 7,902 goats of West African Dwarf breeds were sampled of which only 4 (0.08%) of sheep and 42 (0.53%) of goats were confirmed positive for mange infestation. In all the LGAs sampled, Odeda LGA had the highest concentration of sheep (39%) and goats (51%) while Abeokuta South had the least percentage of sheep (1%) and goats (1%). All the mange-infested cases in sheep were recorded in just one LGA (Ewekoro) which constituted 0.24% of the population within the location. For goats, three out of five LGAs namely: Obafemi Owode, Ewekoro and Abeokuta North had prevalence of 1.46%, 0.53% and 0.72% respectively. There was no significant (P > 0.05) difference between non-infested and infested animals in terms of packed cell volume (31.79 ± 0.87% vs. 31.41 ± 1.13%), haemoglobin (10.51 ± 0.21 g/100 ml vs. 10.28 ± 0.37 g/100 ml) and red blood cells (8.71 ± 0.29 × 10(12)/l vs. 9.40 ± 0.37 × 10(12)/l). The infested group however showed significantly (P < 0.01) higher white blood cells count (7.60 ± 0.22 × 10(9)/l) than the non-infested animals (6.81 ± 0.17 × 10(9)/l). Neutrophil, eosinophil, basophil and monocyte as well as chloride were not significantly affected by the health status of the animals. There existed significant (P < 0.01) difference between non-infested and infested animals in terms of total protein (5.42 ± 0.16 vs. 4.75 ± 0.20 g/dl), sodium (137.98 ± 1.53 vs. 128.92 ± 1.92 mEq/l) and potassium (4.04 ± 0.14 vs. 3.46 ± 0.18 mEq/l). It can be concluded from this study that the prevalence of mange mite infestation varied with location and was generally low or absent in some of the LGAs considered. Goats were particularly more susceptible to mange infestation than sheep. More concerted effort is needed to control mange in order to avoid spread since it is a contagious disease.  相似文献   
32.
Evidence mounts for the influence of climate variability on temporal trends in the phenology of many organisms including various species of fish. Accordingly, we examined variation in adult Atlantic salmon Salmo salar run timing in thirteen Newfoundland and Labrador rivers where returns were monitored at fishways or fish‐counting fences. Run timing varied significantly among rivers with the median date of return differing by up to 5 weeks. Duration of runs was generally short with most adults returning over a period of three to 5 weeks. A mixed model analysis incorporating a first‐order autoregressive error structure was used to generalise changes in run timing among all monitored rivers. Results indicated that the median date of return has advanced by almost 12 days over a 35‐year interval from 1978 to 2012, while several individual rivers have advanced by almost 21 days. The influence of climate on median timing was evident when the simultaneous effects of both climate and salmon abundance were controlled. We found earlier runs associated with overall warmer climate conditions on the Newfoundland and Labrador Shelf. Results contrast with those from the north‐east Atlantic where Atlantic salmon are returning later in some rivers coincident with warming climate conditions.  相似文献   
33.
In dogs diagnosed with solid tumors, regional lymph node involvement or evidence of distant metastasis can predict worse prognoses and significantly decreased survival. Lymph node size alone has been shown to be insufficient as a predictor for the accurate clinical staging of some canine neoplasia. However, certain regional lymph nodes (including those of the oral cavity) are difficult to access for routine tissue sampling. Diffusion weighted magnetic resonance imaging (MRI) has demonstrated the ability to differentiate metastatic from inflammatory/benign lymph nodes in clinical studies with human cancer patients through the calculation of quantitative values of diffusion termed apparent diffusion coefficients (ADC). The objective of this prospective, exploratory study was to evaluate diffusion‐weighted MRI and ADC as potential methods for detecting metastatic lymph nodes in dogs with naturally occurring disease. We hypothesized that diffusion‐weighted MRI would identify significantly different ADC values between benign and metastatic lymph nodes in a group of canine patients with head or neck disease. Our study population consisted of eight client‐owned canine patients, with a total of 20 lymph nodes evaluated (six metastatic, 14 benign). Our results demonstrated that two of four observers identified a significant difference between the mean ADC values of the benign and metastatic lymph nodes. When data from all four observers were pooled, the difference between the mean apparent diffusion coefficients values of the benign and metastatic lymph nodes did not reach significance (P‐value = 0.0566). Findings indicated that diffusion‐weighted MRI is a feasible method for further characterizing enlarged lymph nodes in dogs with head and neck disease, however measured ADC values did not differ for benign vs. metastatic lymph nodes in this small sample of dogs.  相似文献   
34.
35.
The effects of elevated dietary arginine on the hematology and immune function of juvenile channel catfish Ictalurus punctatus were evaluated by means of in vivo and in vitro experiments. Healthy juvenile channel catfish (average weight, 34.8 g) were fed casein-gelatin-based diets containing 28% crude protein and supplemented with crystalline L-arginine (ARG) at 0.5, 1, 2, or 4% of diet. An intact-protein diet containing 1.3% arginine also was included to investigate the effects of amino acid form (crystalline-free amino acids versus intact protein). Each purified diet was fed to apparent satiation to triplicate groups of fish for 6 weeks. At the end of the experimental feeding period, the fish were injected intraperitoneally with two doses (3 d apart) of 2 mg lipopolysaccharide/kg body weight. Six days after the initial injection, the fish were anesthetized and tissue samples were obtained to evaluate hematological and humoral and cellular immune parameters, including phagocytic activity of peritoneal macrophages, hemoglobin, hematocrit, mean corpuscular volume (MCV), blood cell counts, plasma protein, and hepatic superoxide dismutase activity. High dietary levels (4% ARG) resulted in significantly higher levels of hemoglobin, hematocrit, and circulating erythrocytes. Dietary ARG did not significantly affect MCV and the number of circulating leukocytes, lymphocytes, eosinophils, and monocytes. In vitro, a moderate level (2 mM) of ARG in the culture media was found to be ideal in significantly enhancing phagocytosis. This study demonstrates that some aspects of the immune system of channel catfish are sensitive to changes in dietary ARG.  相似文献   
36.
Two trials were conducted to determine the efficacy of fish fed live yeast Debaryomyces hansenii strain CBS 8339 on immune and antioxidant systems in leopard grouper Mycteroperca rosacea infected with Aeromonas hydrophila. Juveniles (12±0.5 g) were fed with a control diet or a D. hansenii‐supplemented diet (106 colony‐forming units per gram) for 5 weeks. The live weight of fish was registered on a weekly basis. After 4 weeks, fish from each treatment were immunocompromised with pathogenic A. hydrophila and further fed for 1 week in order to evaluate the effect on immunological and antioxidant parameters. Generally, the results showed enhanced growth performance in fish fed the diet containing yeast compared with the control. Addition of live yeast had no significant effect on the immunological parameters after 4 weeks of feeding. However, post infection with A. hydrophila fish fed the yeast‐supplemented diet resulted in a significant increase in the levels of plasmatic immunoglobulin M. Superoxide dismutase and catalase (CAT) activities were significantly higher in the yeast group. In this fish, CAT and heat shock protein 70 genes were up‐regulated before and after infection of A. hydrophila. The present study is the first one reporting that yeast (D. hansenii) can enhance immunity and resistance against A. hydrophila.  相似文献   
37.
The influence of dietary protein/lipid levels on growth and survival in juvenile crayfish (Procambarus acanthophorus) was evaluated during a 12‐week nutritional trial. Twenty experimental diets were formulated containing different protein (200, 250, 300, 350 and 400 g kg?1) and lipid (60, 80, 100 and 120 g kg?1) levels. A bifactorial model (5 × 4) was used with three replicates and 15 crayfish (0.014±0.006 g) per replicate, in a recirculation system with 60–15 L rectangular tanks and a biological filter, the culture conditions were a photoperiod of 12:12 h L:D and temperature 24.7±1.0 °C. Total survival ranged from 66.6% to 86.6%, with no differences attributed to treatments. Dietary protein levels had a significant effect on growth gain and nutritional efficiency; in contrast, lipid levels had no effect on juvenile performance. The 250/120 (protein/lipid) treatment promoted the most efficient growth (final weight: 3.09 g, weight gain: 21 995%, specific growth rate: 3.35% day?1); the less efficient growth was observed in juveniles fed with 400 g kg?1 protein diets. The quadratic regression model indicated 279 g kg?1 as the optimal protein level for crayfish growth, while levels between 211 and 232 g kg?1 could minimize the feeding costs without affecting growth.  相似文献   
38.
During a growout period of 14 weeks, the productive performance, organosomatic indices and body composition of the Nile tilapia Oreochromis niloticus cultivated at high density reusing the water from systems with biofloc technology (BFT) were evaluated. Two treatments: tilapia cultured in biofloc (TB) and tilapia cultured in reused water biofloc (RW) were established. Mixed sex, juvenile Nile tilapia (average weight and length: 79.28 ± 14.44 g and 12.44 ± 0.70 cm) were stocked into 6 experimental units (0.2 m3) at a density of 100 fish/m3. Temperature, dissolved oxygen, total dissolved salts, pH, NH4–N, NH3–N and NO3–N were recorded daily, while NO2–N, general hardness, carbonate hardness and settleable solids were recorded weekly. The weight and length of the tilapias were recorded biweekly. Survival, productive performance, proximal composition and organosomatic indices of Nile tilapia were evaluated. The water parameters in RW treatment such as pH, total dissolved salts, NO2–N, NO3–N and carbonate hardness were significantly greater (p < 0.05), when compared to those obtained in TB treatment. Survival rate was > 98% under both treatments. The final weight (TB = 163.09 ± 42.34 g, RW = 159.23 ± 39.92 g), protein (19.1%) and lipid (2.2%) content of the tilapia were non-significantly different between treatments. In addition, no significant differences in the gonadosomatic and hepatosomatic indices were observed either between tilapia sex or between the treatments. The results suggest that the intensive cultivation of Nile tilapia in biofloc can be established using reuse water from BFT systems, without adverse effects on their survival, productive performance, proximal composition and gonadal development.  相似文献   
39.
40.
The degree of hydrolysis (DH) of the ingredients was evaluated for Centropomus undecimalis juveniles. The in vitro experiment included wheat gluten (WG), corn gluten (CG), soybean meal (SBM) and pretreated phytase (SBM + phytase), soy protein concentrate (SPC), canola meal (CAN) and pretreated phytase (CAN + phytase), poultry byproduct meal (PBPM), chicken meal (CHKM), dried whey (DW), Pota meal (PM: mix of giant squid, fish soluble protein concentrate, crustacean meal, and fish oil), and Protiblend (PTB: aquatic and render mix). The highest acidic DH occurred with PTB (0.38 ± 0.06), CHKM (0.33 ± 0.3), and PBPM (0.25 ± 0.03). In the alkaline condition, PTB (1.6 ± 0.17 and 0.98 ± 0.05 for pyloric caeca and intestine, respectively) and CG (1.04 ± 0.4 and 0.75 ± 0.2 for caeca and intestine, respectively) provided the highest DH values. In vitro digestibility demonstrated that PTB was the highest (85.3%) followed by PBPM (51.4%), CAN + phytase (47.6%), CG (45.1%), and CHKM (46.5%). The in vivo experiment concerned the WG, CHKM, PBPM, PM, and PTB diets plus a reference diet with fishmeal (Ref diet). The total %DH was different (P < 0.05) with the lowest values for the WG diet (0.34 ± 0.09%) and Ref diet (0.34 ± 0.15). Free amino acid released during digestion was displayed for these diets and a bifactorial analysis produced no difference (P > 0.05). The apparent digestive coefficients ranged from 89.8 to 92.9% for protein and from 68 to 71.4% for energy.  相似文献   
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