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1.
Clostridium chauvoei CH3 and Kad1 strains were found to cause marked changes in the blood parameters during the course of blackleg disease. These changes displayed by CH3 were found to be more marked than the local Kad1 strain. Results of changes in the haematological values in calves infected with blackleg organisms, showed an increase in RBC, PCV, Hb and the total leukocyte count. MCHC and MCH remained within normal range values, however, a terminal significant increase of MCV was obtained. Thrombocytes showed a steady drop after infection to the time of death of the animals.  相似文献   
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1. The effects of continuous infusion of 0.1, 1.0 and 10.0 mU/min/kg body weight of arginine vasotocin (AVT) or mesotocin (MT) on cardiovascular and thermoregulatory responses, on plasma osmolality and ionic composition and on plasma concentrations of AVT, MT, prolactin and aldosterone, were investigated in conscious White Leghorn cockerels.

2. Neither of the peptides, at any dose, affected cardiovascular functions, plasma ions and osmolality. Infusion of MT at the rate of 10 mU/min/kg body weight increased respiratory rate. Both peptides at doses of 1 and 10 mU/min/kg reduced the temperatures of the comb and shank but had no effect on the skin and cloaca.

3. Doses of 0.1 and 1.0 mU MT/mu/kg reduced plasma aldosterone and at 10 mU/min/kg increased plasma AVT. At any given dose MT had no effect on plasma prolactin. AVT at 0.1 and 1.0 mU/min/kg of AVT reduced plasma MT. AVT at 1.0 mU/min/kg increased plasma prolactin and at 10 mU/min/kg reduced plasma aldosterone.

4. During saline infusion, plasma MT was positively correlated with plasma AVT and negatively correlated with respiratory rate and cloacal temperature. Plasma AVT showed a positive correlation with plasma MT and aldosterone and a negative correlation with respiratory rate and skin temperature.

5. During saline infusion, there was no significant correlation between cardiovascular functions, or plasma osmolality and ionic composition and plasma MT or AVT.

6. The present study suggests that interrelationships between circulating concentrations of AVT and MT do exist and that AVT affects  相似文献   

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Tropical Animal Health and Production - Small ruminants’ production contributes to livelihood of pastoral communities, but this faces myriad constraints. This study aimed at identifying...  相似文献   
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Various methods are being employed to detect early pregnancy in domestic animals. This study aimed to predict early pregnancy in buffaloes via measuring the corpus luteum (CL) diameter, the luteal blood flow (LBF) area, the uterine blood flow (UBF) vascularization area, and progesterones in saliva and serum for non-pregnant (NPBs, N = 12) and pregnant (PBs, N = 12) buffaloes. The results revealed that the CL diameter and the luteal color blood flow blue and red (P = 0.0001) areas of the pregnant animals kept increasing from day 1 to day 35 of the gestation period, but it decreased in NPBs on day 21 after reaching a peak from ovulation to day 18. Interestingly, the UBF of the pregnant buffaloes (PBs) kept increasing (P = 0.0001) from ovulation to day 42. The difference of the CL diameter (P = 0.03) and the LBF color blue vascularization area (P = 0.002) between PBs and NPBs became clear from day 14 after ovulation, though the difference of UBF between PBs and NPBs became markedly obvious from day 7 after breeding. Both saliva (P = 0.001) and serum (P = 0.0001) progesterones of PBs continued increasing (P = 0.0001) from day 14 to day 35, but those of NPBs started decreasing (P = 0.0001) from day 14 and reached low values on day 21. Therefore, measuring saliva progesterone in addition to the high LBF (day 14) and UBF (day 7) of the pregnant buffaloes using a Doppler ultrasound could be applicable as noninvasive methods to detect early pregnancy and to improve reproductive management of buffaloes.  相似文献   
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Avian pathogenic E. coli (APEC) is the etiologic agent of avian colibacillosis, the most common disease responsible for chicken morbidity in the world. Although multiple virulence-associated factors were identified, their prevalence in Algeria is still poorly known. In the present research, 92 avian pathogenic E. coli (APEC) isolates were recovered from broilers with clinical signs and lesions of colibacillosis. In addition, 32 E. coli isolates collected from feces of healthy birds (AFEC) were included for comparison. All isolates were investigated by PCR for the presence of a total of 11 virulence-associated genes described for avian pathogenic (iroN, ompT, hlyF, iss, iutA, and fimC) and diarrheagenic E. coli (eae, stx, elt/est, ipaH, and aggR). The sensitivity of 39 APEC isolates to 16 antibiotics was also determined using antimicrobial pretreated microplates. Here, we report that 98% of the examined isolates host at least one of the tested virulence factors. The most prevalent genes in APEC were iutA (90.6%), ompT (86.9%), and iss (85.8%); whereas, iutA (78.1%), fimC (78.1%), and iroN (68.7%) were the highest prevalent genes in AFEC. Our data showed that none of the AFEC isolates harbor any of the tested diarrheagenic genes. Moreover, only elt/est (5.4%), stx (2.1%), and ipaH (2.1%) genes were carried by APEC isolates. We further established that ceftazodime, ceftiofur, mequindox, amoxicillin/clavulanic acid, and meropenem were the most efficient antibiotics against the analyzed APEC isolates. Overall, our findings provide more insights about APEC and AFEC virulence potential in Algeria which could participate in the fight against colibacillosis.  相似文献   
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Essential oils are plant-derived aromatic volatile oils, and they contain bioactive compounds that have been shown to improve poultry nutrition. In this study, we investigated the effects of oregano essential oil (OEO) on intestinal antioxidative capacity, immunity, and gut microbiota of young yellow-feathered chickens. A total of nine hundred and sixty 1-d-old female Qingyuan partridge chickens were randomly allocated to four treatment groups with six replicates of 40 birds each, and the feeding trial was lasted for 30 d. The controls were fed on a basal diet without in-feed antibiotics; the birds in the antibiotic group were fed the basal diet supplemented with 20 mg/kg virginiamycin; the remaining birds were fed the basal diet containing 150 or 300 mg/kg OEO, respectively. Dietary supplementation with 150 or 300 mg/kg OEO increased average daily feed intake (P = 0.057) and average daily gain (P < 0.05). The activities of glutathione peroxidase and total antioxidative capacity in plasma, jejuna, and ileal mucosa were increased by OEO supplementation (P < 0.05), with a trend of lower jejunal content of malonaldehyde (P = 0.062). Moreover, dietary OEO increased the content of secretory immunoglobulin A (P = 0.078) and the relative expression of Claudin 1, Mucin 2, and Avain beta-defensin 1 in ileum (P < 0.05). Sequencing data of 16S rRNA indicated that dietary OEO increased the relative abundance of Firmicutes phylum, and Clostridium and Lactobacillus genera, and decreasing that of Romboutsia. Functional analyses indicated that microbial amino sugar and nucleotide sugar metabolism, replication, and repair systems were higher in OEO groups than those of controls and antibiotic treatment. In conclusion, dietary supplementation with OEO enhanced growth performance, alleviated local oxidative stress in intestine, improved production of natural antibodies, and favorably modulated intestinal microbiota composition.  相似文献   
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