A Comparison of Arterial and Lingual Venous Blood Gases in Anethetized Dogs

The purpose of this study was to determine whether lingual vanous blood gas samples reflect arterial acid-base gas status in anethetized dogs. Heparinized blood samples were drawn simultaneously from the lingual vein and a peripheral artery in 50 anestheized dogs that were clinical surgical patients, as well as from four experimental dogs in which hemorrahaic shock was being studied. Blood pH, oxygen tension (PO₂), and bicarbonate (HCO_3-)) from the two sources in clinical patients showed significant liner correlation, although arterial PO₂)(PaO₂)) tended to be approximately 110mm Hg higher than lingual venous PO₂). During hemorrahgic shock, however, PaO₂) and PaCO₂) were significantly different from lingual venous PO₂) and PCO₂), Lingula venous blood gas analysis may be useful in assessing acid-base and blood gas status in routline cases, but should not be relied upon in dogs with low cardiac output or poor perfusion.     

Characterization of and radioimmunoassay for canine thyroglobulin

Canine thyroglobulin (cTg) has been isolated and purified. It has similar electrophoretic patterns as Tg from other mammalian species. The main fraction had a MW of 660,000, whereas also fractions of a MW of approximately 1,300,000 (dimer) and 330,000 (subunit) were present. The iodine content was 0.8 to 1.0 % (w/w). cTg did not cross-react with antibodies against human Tg to a degree that would allow the use of a radioimmunoassay for human Tg for the determination of cTg in serum or plasma. Therefore a polyclonal antiserum was raised against cTg and a homologous radioimmunoassay was developed, which was sensitive (0.4 μg/l) and specific (cross-reactivity in cTg assay of human Tg, goat Tg, T₄, T₃, and DIT < 0.01 %).

Plasma Tg levels in normal dogs of both sexes and aged 3–15 years amounted to 192 ± 73 μg/l (mean ± SD, n=30). There was no relation between plasma Tg and T₄ levels.     

Fluid accumulation in mouse ligated intestine inoculated with the vascular permeability factor produced by Bacillus cereus.

Partially purified vascular permeability (VP) factor (VPF) of Bacillus cereus induced fluid accumulation in the ligated intestinal loops of mouse (MIL) and rabbit (RIL), suggesting that the VP activity may correlate with fluid accumulation in ligated intestinal loops of these animals. Fluid accumulation was observed at 6-8 hr in 55-67% of mouse intestinal loops inoculated with 40-50 immunodiffusion units (IDU) of partially purified VPF, whereas it was found at 2 hr in all loops with 400-600 IDU of partially purified VPF. In rabbit intestinal loops with 120-190 IDU of partially purified VPF, fluid accumulation was observed at 6 hr. From these findings, VPF produced by B. cereus can be easily detected in both MIL and RIL. The intestinal tissue of mouse intestinal loops was histopathologically damaged at different concentrations of the VPF to induce fluid accumulation. With 50 IDU of partially purified VPF, severe edema was found in the laminia proprial layer and submucosa. With 600 IDU of partially purified VPF, on the other hand, severe necrosis in the surface epithelium of villus and laminia proprial layer, and hyperemia in the submucosa were observed, suggesting that partially purified VPF may be cytotoxic and/or intestinecrotic.     

Ⅱ型猪环状病毒是断奶后全身消耗性综合征的致病因子

Ⅱ型猪环状病毒 (PCV2 )现已被证明是断奶后全身消耗性综合征 (PMWS)的致病因子 ,这一综合征是一种可造成世界各地严重经济损失的猪病。最近的研究还证实此病毒与加拿大和欧洲猪群的繁殖障碍有关。但是 ,绝大多数PCV2感染都是亚临床性的。刺激仔猪免疫系统是感染此病毒后产生临床疾病的重要因子吗 ?     

用于免疫治疗和疫苗佐剂的禽细胞因子

随着饲用抗生素及化学药物广泛的禁用 ,需研究替代方法以确保畜牧业不会受到影响 ;对家禽的研究结果表明 ,被饲料中抗生素抑制的产气芽孢杆菌若大量繁殖将会引起胃肠疾病并导致畜产品产量和品质的下降。因此 ,研制促畜禽生长的抗生素替代品至关重要。1　抗生素的替代品一种抗生素替代品如纤维素酶可增加饲料消化率并促进肠道菌群的平衡。消化后的营养成分被鸡体吸收用于能量代谢和生长而不是被肠道微生物消耗。另一个替代品是甜菜碱 ,它能降低肠道寄生虫如艾美耳球虫引起的损伤 ,抑制球虫的再次感染 ,降低肠炎的发生率。细菌素是由某些细菌…     

Impact of pig slurry on soil properties, water salinization, nitrate leaching and crop yield in a four-year experiment in Central Spain

Abstract. The repeated application of pig slurry to agricultural soils may result in an accumulation of salts and a risk of aquifer pollution due to nitrate leaching and salinization. Under Mediterranean conditions, a field experiment on a sandy loam soil (Typic Xerofluvent) was performed with maize (Zea mays) in 1998, 1999 and 2001 to study the effects of applying optimal (P1) and excessive rates (P3) of pig slurry on soil salinization, nitrate leaching and groundwater pollution. The rate of pig slurry was established considering the optimal N rate for maize in this soil (170, 162 and 176 kg N ha^?1 for 1998, 1999 and 2001, respectively). Pig slurry treatments were compared to an optimal N rate supplied as urea (U) and a control treatment without N fertilizer (P0). The composition of the slurries showed great variability between years. Mean NO₃^? leaching losses from 1998 to 2001 were 329, 215, 173 and 78 kg N ha^?1 for P3, P1, U and P0 treatments, respectively. The amount of total dissolved salts (TDS) added to the soil in slurry application between 1998 and 2001 was 2019 kg TDS ha^?1 for the P1 treatment and 6058 kg TDS ha^?1 for the P3 treatment. As a consequence, the electrical conductivity (EC) of the slurry‐treated soils was greater than that of the control soil. The EC correlated significantly with the sodium concentration of the soil solution. Over the entire experimental period, 2653, 2202 and 2110 kg Na ha^?1 entered the aquifer from the P3, P1 and P0 treatments, respectively. The P3 treatment did not significantly increase grain production in 1999 and 2001 compared with that achieved with the optimal N rate treatment (P1). This behaviour shows the importance of establishing application guidelines for pig slurry that will reduce the risk of soil and groundwater pollution.