运输应激对比格犬血常规及生化指标的影响

为了研究运输应激伴随的冷应激、驱赶、捕捉及饲料改变等多重应激对比格犬血常规和血液临床生化指标造成的影响,并且评估1周适应性饲养时间的合理性。以30只比格犬作为试验对象,对其适应性饲养前后的血常规和血液临床生化指标进行检查,并对数据进行分析发现,适应性饲养前犬的血常规和生化指标都有显著变化,1周的常规适应性饲养后,犬应激症状消失,血常规和生化检查指标均回复正常;这说明应激对比格犬造成了显著的影响,1周的适应性饲养是合理且必须的。     

鹿血清蛋白抗氧化肽体外抗氧化性及其机理研究

在碱性蛋白酶最适条件下水解鹿血清蛋白,水解时间为0~5 h,鹿血清蛋白抗氧化肽的水解度(DH)随着水解时间增加而增加(P0.05),鹿血清蛋白抗氧化肽还原能力、清除自由基的作用和Cu2+螯合能力随着水解时间的增加而显著提高(P0.05),鹿血清蛋白抗氧化肽能有效抑制硫代巴比妥酸反应物质(TBARS)生成(P0.05)。结果表明,鹿血清蛋白抗氧化肽的抗氧化活性取决水解时间,鹿血清蛋白抗氧化肽是有效的抗氧化剂。     

Intermedin inhibits pulmonary collagen synthesis in rats with pulmonary hypertension induced by high pulmonary blood flow

AIM: To explore the regulatory effect of intermedin (IMD) on pulmonary collagen synthesis and accumulation in rats with pulmonary hypertension induced by high pulmonary blood flow.METHODS: Healthy male SD rats (n=20) were randomly divided into control group (n=7), shunt group (n=7) and shunt with IMD group (n=6). The shunting of abdominal aorta and inferior vena cava was produced in rats of shunt group and shunt with IMD group. After 8 weeks, IMD was administered into the rats of shunt with IMD group subcutaneously by mini-osmotic pump for 2 weeks. Mean pulmonary artery pressure (mPAP), relative medial thickness (RMT) of pulmonary arteries, contents of hydroxyproline, collagen type I and III, bone morphogenetic protein-2 (BMP-2), and the mRNA expression of procollagen I and III in lung tissues were measured and compared. RESULTS: Compared with control group, mPAP and RMT of medium and small pulmonary arteries in the rats of shunt group were significantly increased. Meanwhile, the lung hydroxyproline, collagens I and III and BMP-2 contents, and the mRNA expression of lung procollagen I and III were all significantly increased compared with control group. However, IMD significantly decreased mPAP, alleviated the changes of pulmonary vascular micro-structure, decreased the collagen accumulation and pulmonary tissue homogenate BMP-2 contents, and inhibited the mRNA expression of procollagen I and III in the lung tissue of shunting rats.CONCLUSION: IMD plays a protective role in the development of pulmonary hypertension and pulmonary vascular structural remodeling induced by high blood flow by inhibiting pulmonary collagen synthesis and accumulation, possibly in association with the BMP-2 pathway.     

Comparison of invasive and oscillometric blood pressure measurement techniques in anesthetized sheep,goats, and cattle

ObjectiveTo determine the level of agreement between an oscillometric (O-NIBP) and an invasive method (IBP) of monitoring arterial blood pressure (ABP) in anesthetized sheep, goats, and cattle.Study designProspective clinical study.AnimalsTwenty sheep and goats, 20 cattle weighing <150 kg body weight, and 20 cattle weighing >150 kg body weight.MethodsAnimals were anesthetized and systolic ABP (SABP), mean ABP (MABP), and diastolic ABP (DABP) were measured using IBP and O-NIBP. Differences between IBP and O-NIBP, and 95% limits of agreement (LOA) between SABP, MABP, and DABP values were assessed by the Bland–Altman method.ResultsMean difference ± standard deviation (range) between SABP, DABP, and MABP measurements in sheep and goats was 0 ± 16 (-57 to 38) mmHg, 13 ± 16 (-37 to 70) mmHg, and 8 ± 13 (-34 to 54) mmHg, respectively. Mean difference between SABP, DABP, and MABP measurements in small cattle was 0 ± 19 (-37 to 37) mmHg, 6 ± 18 (-77 to 48) mmHg, and 4 ± 16 (-73 to 48) mmHg, respectively. Mean difference between SABP, DABP, and MABP measurements in large cattle was -18 ± 32 (-107 to 71) mmHg, 7 ± 29 (-112 to 63) mmHg, and -5 ± 28 (-110 to 60) mmHg, respectively. The 95% LOAs for SABP, DABP, and MABP were -31 to +31, -19 to +44, and -19 to +34 mmHg, respectively in sheep and goats; were -37 to +37, -19 to +44, and -19 to +34 mmHg, respectively in small cattle; and were -81 to +45, -50 to +63, and -59 to +50 mmHg, respectively in large cattle.ConclusionsAgreement was poor between O-NIBP and IBP monitoring techniques.Clinical relevanceArterial BP should be monitored in anesthetized sheep, goats, and cattle using IBP.     

Hyoscine‐N‐butylbromide premedication on cardiovascular variables of horses sedated with medetomidine

ObjectiveTo evaluate the effects of intravenous (IV) or intramuscular (IM) hyoscine premedication on physiologic variables following IV administration of medetomidine in horses.Study designRandomized, crossover experimental study.AnimalsEight healthy crossbred horses weighing 330 ± 39 kg and aged 7 ± 4 years.MethodsBaseline measurements of heart rate (HR), cardiac index (CI), respiratory rate, systemic vascular resistance (SVR), percentage of patients with second degree atrioventricular (2^oAV) block, mean arterial pressure (MAP), pH, and arterial partial pressures of carbon dioxide (PaCO₂) and oxygen (PaO₂) were obtained 5 minutes before administration of IV hyoscine (0.14 mg kg^?1; group HIV), IM hyoscine (0.3 mg kg^?1; group HIM), or an equal volume of physiologic saline IV (group C). Five minutes later, medetomidine (7.5 μg kg^?1) was administered IV and measurements were recorded at various time points for 130 minutes.ResultsMedetomidine induced bradycardia, 2^oAV blocks and increased SVR immediately after administration, without significant changes in CI or MAP in C. Hyoscine administration induced tachycardia and hypertension, and decreased the percentage of 2^oAV blocks induced by medetomidine. Peak HR and MAP were higher in HIV than HIM at 88 ± 18 beats minute^?1 and 241 ± 37 mmHg versus 65 ± 16 beats minute^?1 and 192 ± 38 mmHg, respectively. CI was increased significantly in HIV (p ≤ 0.05). Respiratory rate decreased significantly in all groups during the recording period. pH, PaCO₂ and PaO₂ were not significantly changed by administration of medetomidine with or without hyoscine.Conclusion and clinical relevanceHyoscine administered IV or IM before medetomidine in horses resulted in tachycardia and hypertension under the conditions of this study. The significance of these changes, and responses to other dose rates, requires further investigation.     

Effect of sub-lethal nitrite on selected haematological parameters in fingerling Catla catla (Hamilton)

A sub‐lethal nitrite toxicity trial was conducted using static conditions for a period of 96 h with fingerlings of Catla catla (21.4±3.6 g). Fingerlings were exposed to five concentrations of nitrite, that is, 1, 2, 4, 8 and 10.4 mg L^?1 and a nitrite‐free control to study changes in haematological parameters. Nitrite caused an increase in immature erythrocyte population (7–24%) in lower concentrations (0–4 mg L^?1) at 6 h while they were absent in higher concentrations. The total erythrocyte count was reduced at 6 h followed by an increase at 12 h with further reduction up to 96 h in all concentrations of nitrite. The 96‐h exposure resulted in 21.2–31.8% reduction in erythrocyte population in 1–10.4 mg L^?1 nitrite. The haemoglobin content decreased progressively with increasing nitrite concentrations as well as exposure periods. Total leukocyte count decreased initially at 6 h in all treatments followed by an increase after 12 h, signifying development of a protective response of the body to nitrite stress. Blood glucose decreased initially up to 24 h followed by an increase through 96 h. Serum protein level decreased continuously with increasing exposure period. The study revealed that exposure to nitrite caused changes in almost all the haematological parameters in the fingerlings depending on the concentration as well as exposure period. Nitrite being one of the important inorganic nutrients often recorded at higher levels in intensively cultured ponds, the present study highlights its adverse impact on fish and stressed the need for the management of this nutrient in culture ponds.     

Feed deprivation of channel catfish, Ictalurus punctatus (Rafinesque), influences organosomatic indices, chemical composition and susceptibility to Flavobacterium columnare

Withholding feed has been suggested as a strategy to manage infectious disease of channel catfish, Ictalurus punctatus (Rafinesque). In a previous study, we demonstrated that deprivation of feed for as little as 7 days reduced innate resistance of catfish to Flavobacterium columnare. This study was conducted to evaluate the effect of feeding regimens [no feeding (NF), fed once every other day to satiation (FEOD) and fed once daily to satiation (FD)] on organosomatic indices, physiological changes and susceptibility of channel catfish to F. columnare. Fish that were not fed for 2 and 4 weeks had a significant increase (P < 0.05) in gutted weight:-wet weight ratio and decrease in other organosomatic indices [gut index (GI), mesenteric fat index (MFI) and hepatosomatic index (HSI)]. Haematology was not effected by feeding regimen except at week 4, when a significantly higher haemoglobin level was observed in the NF fish. Serum protein did not differ at week 2, but the level at week 4 of the NF fish (35.91 mg mL(-1)) was significantly lower than that of the FD fish (41.77 mg mL(-1)). Significantly lower (P < 0.05) blood glucose (39.5 and 40.3 mg dL(-1)) and liver glycogen (1.7 and 1.8 mg g(-1)) were seen in the NF fish at weeks 2 and 4, respectively, as compared with blood glucose and liver glycogen levels of FD fish (67.5 and 92.8 mg dL(-1) and 46.5 and 52.6 mg g(-1) at weeks 2 and 4, respectively) and FEOD (82.8 and 85.5 mg dL(-1) and 45.1 and 51.4 mg g(-1) at weeks 2 and 4, respectively). Mortality in the NF fish caused by F. columnare (78%) was significantly higher (P < 0.05) than mortality in the FD and FEOD treatments (0.0 and 1.7%, respectively). Blood glucose and liver glycogen showed the same trend of low values for NF fish following challenge (week 6). Blood glucose, liver glycogen, GI and HSI are sensitive indicators for channel catfish deprived of feed (NF) for 4 weeks. Blood glucose and liver glycogen levels around 40 mg dL(-1) and 2 mg g(-1), respectively, are indicative of starvation in juvenile channel catfish. Moreover, NF fish were susceptible to F. columnare infection. Thus, it is suggested that in the absence of natural food, juvenile channel catfish should be fed at least once every other day to apparent satiation to maintain normal physiological function and improve resistance to F. columnare.