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Tropical Animal Health and Production - The effect of hemoglobin polymorphism on performance traits in Nigerian indigenous chicken types was investigated in this research. The chickens were...  相似文献   
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The ultrastructural morphology of the eosinophil was studied in specimens of peripheral blood from normal adult camels and those with eosinophilia. Specific granules were extremely polymorphic. The specific granules exhibited the basic structure of an electron-dense crystalloid core surrounded by a lighter, homogeneous matrix. The crystalloid cores were extremely variable in size and shape, often were segmented and demonstrated a variety of lamellated patterns that were transverse, longitudinal or concentric to the long axis of the core. It was not uncommon to observe multiple crystalloid cores in a single granule. In addition to large specific granules, microgranules and specific microgranules were observed. The extreme polymorphism of the specific granules and variety of lamellated patterns differentiate camel eosinophils from those of other species.  相似文献   
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梨果实石细胞团的发育,分布及其对果实品质的影响   总被引:12,自引:0,他引:12  
1997年对梨果实石细胞团的发育和分布进行了观察分析,供试品种43个。通过对苹果梨、南果梨、丰水梨,伏茄梨四个品种的石细胞团形成过程的观察,及43个梨品种的成熟果实中石细胞团大小和分布的观察测定发现,梨果实石细胞团的形成从花后15d左右开始,花后2个月内基本结束,梨果实中石细胞团分布一般以近果皮处和近果心处密度高、直径大,中层果肉中石细胞团密度低,直径小,果实中石细胞团直径较大,密度高的品种肉质较  相似文献   
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This study investigated the influence of Bacillus‐based probiotics on performance and intestinal health in broiler challenged with Clostridium perfringens‐induced necrotic enteritis. One‐day‐old Arbor Acre (n = 480) were randomly assigned to four treatments with 10 cages of 12 birds: (a) basal diet negative control (NC), with no probiotics nor antibiotics formulated to contain 2,930 and 3,060 kcal/kg with 24.07 and 15.98% CP, for starter and finisher diet, respectively, (b) basal diet + enramycin (5 mg/kg), an antibiotic growth promoter (AGP); (c) basal diet + Bacillus subtilis B21 at 2 × 109 CFU per g (BS); (d) basal diet + Bacillus licheniformis B26 at 2 × 109 CFU per g (BL); growth performance, intestinal morphology, intestinal lesion scores, short‐chain fatty acids (SCFAs) and mucosal barrier tight junction's (TJ) mRNA expression were assessed. NC‐ and BL‐fed groups showed higher (p = 0.005) average daily feed intake from d1 to d21 than AGP and BS, whereas BS‐ and AGP‐fed groups showed higher average daily weight gain from d22 to d42 and d1 to d42 of age. Higher mortality rate of (12.5%) and lower of (5.5%) were recorded in AGP and NC fed‐groups respectively, lesion score was higher in BS and BL than in AGP, while no lesion was observed in NC group, results revealed higher duodenum and jejunum villus height to crypt depth (VH:CD) compared with NC and BS. Probiotics‐fed groups showed higher total (SCFAs), acetic and butyric acid concentrations at d21 post‐challenge (PC) than other groups. The expression of claudin‐1 was upregulated in duodenum (d7) PC and in jejunum (d7) and (d21) PC in BL group, while at d21 PC, the expression of occludens was higher in jejunum and ileum by AGP and BL. The present study indicated both BS and BL have some similarity with AGP in preventing or partially preventing NE effect in broilers.  相似文献   
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Tropical Animal Health and Production - Prevalence and distribution of Shiga toxin-producing Escherichia coli (STEC) serogroups from the faecal samples of cattle and camels slaughter in Maiduguri...  相似文献   
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Clinical signs of severe bronchopneumonia, including anorexia, coughing, nasal discharge, dyspnoea, diarrhoea, distension of the neck, lethargy, recumbency, lameness preceding collapse, and death were observed among a herd of Holstein–Friesian dairy cattle. The outbreak occurred over a 30-day period, and attack and case-fatality rates were 0.4% and 50%, respectively. At necropsy, extensive consolidation in the cranioventral parts of the lungs was observed. Histologically, a severe acute bronchopneumonia with slight pleuritis was present. Both pathological and bacteriological evaluation of the lungs incriminated Histophilus somni (heavy growth). Supplementary laboratory investigations also isolated Clostridium and Klebsiella species (scanty growth) from the lungs. Histophilosis in cattle was confirmed for the first time in Nigeria.  相似文献   
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