湖羊胚胎和精液超低温保存效果的评价

【目的】 检验长期保存在国家家畜基因库的湖羊冷冻胚胎和冷冻精液的质量,评价超低温冷冻保存技术保种的效果。【方法】 对保存于国家家畜基因库的冷冻胚胎（保存20年）和冷冻精液（保存20和30年）进行复苏,进行相应鉴定后分别进行胚胎移植和人工授精,同时以0年冷冻精液和新鲜精液为对照,测定其受胎率和后代的羔皮性能、生长性能及繁殖性能,检验保存效果。【结果】 本试验共解冻胚胎36枚,其中,A级胚胎22枚,B级胚胎7枚,C级胚胎5枚,D级胚胎2枚,冷冻胚胎复苏利用率达到94.44%（34/36）,A级胚胎率达到61.11%（22/36）,移植34枚,产羔17只,冷冻胚胎复苏移植产羔率达50.00%;保存30年的冷冻精液复苏后平均精子活力达35%,受胎率为58.57%,平均产羔1.90只;保存20年冷冻精液复苏后平均精子活力达31%,受胎率为53.66%,平均产羔1.95只;胚胎复苏移植羊、30和20年冷冻精液后代体型外貌鉴定均符合纯种湖羊特征,没有畸形个体;羔羊一级羔皮率分别是31.25%、42.03%和23.81%,保持了当年湖羊的羔皮特性;生长发育及繁殖性能与现有湖羊群体性能基本保持一致。【结论】 利用超低温冷冻技术长期保存湖羊冷冻胚胎和冷冻精液的方法是可行的,对地方品种保种具有重要意义。     

GI PiCO2: Tissue Specific Monitoring For Improving Patient Outcomes

Improvements in human patient monitoring despite their development in animals, do not always find their way into veterinary clinical use due to financial constraints. Gastrointestinal intraluminal CO₂ partial pressure (Gip₁CO₂) monitoring, however, is not only proving very beneficial in human trauma and critical patient care but is also very likely to become relatively inexpensive. By providing information on the perfusion adequacy of a high risk, critically important tissue, the GI mucosa, GI P₁CO₂ monitoring offers an easily accesible indicator of the efficacy and adequacy of resuscitative interventions. The potential for decreasing morbidity and mortality is enormous. Therefore, the practicing veterinarian should become familiar with GI P₁CO₂ monitoring theory and technology so he or she can be better prepared to incorporate it into practice when in becomes available.     

Assessment of changes in blood volume in response to resuscitative fluid administration in dogs

Objective: To determine the continuous changes in blood volume in response to fluid administration using an in‐line hematocrit monitor. Design: Prospective study. Setting: Research laboratory. Animals: Four healthy dogs. Interventions: Each dog received intravenous boluses of 80 mL/kg of 0.9% saline (S), 4 mL/kg of 7.5% saline (HS), 20 mL/kg of dextran 70 (D), 20 mL/kg of hetastarch (HES), or no fluids (control, C) on separate occasions. Fluids were administered at 150 mL/min in the S, D, and HES groups, and at 1 mL/kg/min in the HS group. Measurements and main results: Blood volume changes were measured every 20 seconds for 240 minutes using an in‐line hematocrit monitor. There was a rapid rise in blood volume during all infusions. Immediately after the administration of crystalloid fluids, the rapid rise in blood volume ceased. Subsequently, there was a steep decline in blood volume for 10 minutes, and a slower decline thereafter. In contrast, the rise in blood volume continued for at least 10 minutes after the infusion of the colloids was complete, and a plateau was observed for the remainder of the experiment. The blood volume effect, as measured by area under the curve, was significantly greater in the saline group than the other groups during the infusion time and for the 0–240 minutes time period. The areas under the curve for the two colloid solutions were not significantly different from each other during any time periods. The percent increase in blood volume immediately following the infusions was 76.4±10.0 in the S group, 17.1±3.2 in the HS group, 23.0±10.5 in the D group, and 27.2±6.4 in the HES group. At 30 minutes from the start of the infusion, the mean percent increases in blood volumes were 35.2±9.3 in the S group, 12.3±0.9 in the HS group, 35.9±7.3 in the D group, and 36.8±6.5 in the HES group. At 240 h post‐infusion, the mean percent increases in blood volume were 18.0±9.7 in the S group, 2.9±6.1 in the HS group, 25.6±16.1 in the D group, and 26.6±8.6 in the HES group. The C group had a mean percent change in blood volume of ?3.7±3.4 at the end of the experiment. Conclusions: This study indicates that the rapid administration of saline at clinically relevant doses leads to the largest immediate increase in blood volume, although this change is transient because of rapid redistribution of the fluid. Despite a brief increase in blood volume that was almost 3 times the volume administered, hypertonic saline led to the smallest increase in blood volume post‐infusion. The synthetic colloid solutions increased the blood volume by an amount greater than that infused and the effect was sustained for a longer period of time than seen following crystalloid administration, but the maximum increase in blood volume was significantly less than saline. The measurement of continuous changes in blood volume, using an in‐line hematocrit monitor, was a useful means of assessing the dynamic effects of fluid administration in dogs in a research setting.