猪(Svs scrofa domastica L)染色体高分辨G带带型

利用加入氨甲喋呤和胸苷使细胞分裂同步化并结合胰酶G带技术,分析了猪前中期染色体高分辨G带。单套染色体的G带数目,包括x和y染色体,前中期为503条,中期为300条。绘制了前中期和中期G带带型图。     

用BLUE法评定猪繁殖性能的杂交效果

用BLUE法分析了青海省养猪繁育体系中母本互助猪,父本杜洛克、长白、汉普夏、大约克、巴克夏、苏白猪和二、三元杂交猪的繁殖效果。结果表明:不同品种和不同杂交组合的繁殖性状之间有明显差异(P<0.05或P<0.01);三元杂交组合的多数繁殖性状极显著的优于纯种亲本,显著优于二元杂交组合,而二元杂交组合也显著优于纯亲本;互助猪产仔数显著高于瘦肉型父本,而瘦肉型父本在改良仔猪生长发育方面则有明显优势。说明我省以三元杂交为主建立养猪繁育体系是适当的,但应注意提高互助猪早期生长发育性能,才能表现出更大的杂种优势。     

淮南猪染色体的研究

采用微量外周血淋巴细胞培养以及核仁组成区银染色(Ag—NORs)技术,对淮南猪体细胞核型以及核仁组成区进行了研究,结果表明,淮南猪二倍体细胞染色体组成为38xy(公)或38xx(母),NF=64;细胞分裂中期银染阳性核仁组成区为1、2、3和4的频率分别为0.3659、0.2683、0.1951和0.1707,平均有2.17条染色体的核仁组成区被正染。     

近交与贴现对优化群体规模的影响

小群体的闭锁选育不可避免产生近交及遗传方差下降，导致近期与远期选择效果的矛盾。本文通过考察猪核心群育种方案中群体规模及公母比例对近交增量（％）及累积育种产出（元）的作用，分析遗传方差下降以及育种产出的贴现等因素对选择方案评估效果的影响。群体有效规模主要受每世代选择公猪头数的影响，为了控制群体近交增量必须维持一定的公猪头数。在所模拟的１６种方案中，１５代的贴现累积选择进展以每代选择８头公猪为最高；而母猪规模越大，累积选择进展越高。不考虑近交引起遗传方差的下降，或不进行选择进展的贴现，都造成过高估计选择方案的效果，且导致选择不适当的方案；对各世代选择进展进行贴现时，需要考虑较大的世代数，否则也会影响各选择方案的比较结果。     

Measurements of the acid-binding capacity of ingredients used in pig diets

: Some feed ingredients bind more acid in the stomach than others and for this reason may be best omitted from pig starter foods if gastric acidity is to be promoted. The objective of this study was to measure the acid-binding capacity (ABC) of ingredients commonly used in pig starter foods. Ingredients were categorised as follows: (i) milk products (n = 6), (ii) cereals (n = 10), (iii) root and pulp products (n = 5), (iv) vegetable proteins (n = 11), (v) meat and fish meal (n = 2), (vi) medication (n = 3), (vii) amino acids (n = 4), (viii) minerals (n = 16), (ix) acid salts (n = 4), (x) acids (n = 10). A 0.5 g sample of food was suspended in 50 ml distilled de-ionised water with continuous stirring. This suspension was titrated with 0.1 mol/L HCl or 0.1 mol/L NaOH so that approximately 10 additions of titrant was required to reach pH 3.0. The pH readings after each addition were recorded following equilibration for three minutes. ABC was calculated as the amount of acid in milliequivalents (meq) required to lower the pH of 1 kg food to (a) pH 4.0 (ABC-4) and (b) pH 3.0 (ABC-3). Categories of food had significantly different (P < 0.01) ABC values. Mean ABC-4 and ABC-3 values of the ten categories were: (i) 623 (s.d. 367.0) and 936 (s.d. 460.2), (ii) 142 (s.d. 79.2) and 324 (s.d. 146.4), (iii) 368 (s.d. 65.3) and 804 (s.d. 126.7), (iv) 381 (s.d. 186.1) and 746 (s.d. 227.0), (v) 749 (s.d. 211.6) and 1508 (s.d. 360.8), (vi) 120 (s.d. 95.6) and 261 (s.d. 163.2), (vii) 177 (s.d. 60.7) and 1078 (s.d. 359.0), (viii) 5064 (s.d. 5525.1) and 7051 (s.d. 5911.6), (ix) 5057 (s.d. 1336.6) and 8945 (s.d. 2654.1) and (x) -5883 (s.d. 4220.5) and -2591 (s.d. 2245.4) meq HCl per kg, respectively. Within category, ABC-3 and ABC- 4 values were highly correlated: R2 values of 0.80 and greater for food categories i, iv, v, vi, vii and viii. The correlation between predicted and observed ABC values of 34 mixed diets was 0.83 for ABC-4 and 0.71 for ABC-3. It was concluded that complete diets with low ABC values may be formulated through careful selection of ingredients. The final pH to which ABC is measured should matter little as ABC-3 and ABC-4 are highly correlated.     

猪血清中天然LFA－3存在的探讨

测定了正常猪血清对ＳＲＢＣ的溶血作用。并根据猪血清对ＳＲＢＣ的破坏作用经ＳＲＢＣ吸收和加入ＳＲＢＣＬＦＡ－３后即显著降低或消失，提出了猪血清破坏ＲＢＣ的作用与血清中游离ＣＤ＿２的存在有关的论断。此外，又根据反复解离和经ＳＲＢＣ吸收后的猪血清具有阻止正常猪血清对ＳＲＢＣ的破坏作用和猪ＰＢＭＣＥ玫瑰花环的形成，认为猪血清中可能存在天然的ＬＦＡ－３，进而对血清游离ＣＤ＿２在淋巴细胞激活中的功能提出了“游离ＣＤ＿２调控途径”的设想。     

Treatment of experimental ureteral strictures by endourological ureterotomy and implantation of stents in the porcine animal model

The objective of this study is to evaluate the dilation of the ureter using endoureterotomy and an expanding-sheath double pigtail ureteral stent in the treatment of experimentally induced ureteral strictures in the porcine animal model. This is a new treatment in the ureteral strictures resolution in Veterinary Urology, although it is not a common affection, it usually appears as a consequence of ureteritis and in the iatrogenic female genital surgery. The experimental study is design in three phases: induction of experimental stricture, diagnosis and treatment of the stricture and follow-up. We have used 10 healthy Large White female pigs. The internal ureteral diameter was measured prior to laparoscopic ligature stricture induction using retrograde ureteropyelography (RUPG). Experimental stricture was diagnosed 4 weeks after intervention, using RUPG and ultrasound, and treated by endoureterotomy and subsequent placement of a double pigtail ureteral stent, which was removed 6 weeks later. The study finished 4 weeks later with measurement of ureteral diameters using RPUG and ultrasound evaluation. Except in one case, all ureters displayed permanent dilation of the strictured area for 10 weeks after treatment (6 weeks with ureteral stent and 4 more weeks without stent). Finally, this technique proved to be effective in cases of short-length and short-living ureteral strictures, and represents a viable alternative to conventional surgery in animals.     

良种猪胴体性状分析及瘦肉率最佳预测模型筛选研究

选择6月龄左右阉割的良种瘦肉型商品猪72头,测瘦肉率、热胴体重、背膘厚度等指标,采用SAS8.2软件建立预测良种猪胴体瘦肉率不同变量的回归方程。结果表明,多元线性方程y=66.158-0.096 7 x1-0.232 4 x4-0.323 x7+0.2 x10能较好的拟合良种猪的胴体瘦肉率,6～7肋膘厚(x4)、腰荐膘厚(x7)、M厚度(x10)被选为瘦肉型良种商品猪分级时需要测量的3个指标。     

Modulation of porcine biotransformation enzymes by anthelmintic therapy with fenbendazole and flubendazole

Fenbendazole (FEN) and flubendazole (FLU) are benzimidazole anthelmintics often used in pig management for the control of nematodoses. The in vivo study presented here was designed to test the influence of FLU and FEN on cytochrome P4501A and other cytochrome P450 (CYP) isoforms, UDP-glucuronosyl transferase and several carbonyl reducing enzymes. The results indicated that FEN (in a single therapeutic dose as well as in repeated therapeutic doses) caused significant induction of pig CYP1A, while FLU did not show an inductive effect towards this isoform. Some of the other hepatic and intestinal biotransformation enzymes that were assayed were moderately influenced by FEN or FLU. Strong CYP1A induction following FEN therapy in pigs may negatively affect the efficacy and pharmacokinetics of FEN itself or other simultaneously or consecutively administered drugs. From the perspective of biotransformation enzyme modulation, FLU would appear to be a more convenient anthelmintic therapy of pigs than FEN.     

Pathological and aetiological studies of multifocal interstitial nephritis in wasted pigs at slaughter

Multifocal interstitial nephritis in pigs has been associated with several infectious agents. The objective of the present study was to investigate several different potential infectious agents associated with "white-spotted" kidneys in pigs suffering from wasting at slaughter (aged 6-8 months). Twenty-nine case kidneys (with a "white-spotted" gross appearance) classified into 3 macroscopic lesional grades, and 15 control kidneys (lacking gross lesions), were obtained from a pig abattoir. Laboratory analyses to detect potential associations with the aforementioned pathological condition with Leptospira spp., porcine circovirus type 2 (PCV2), porcine parvovirus (PPV), porcine reproductive and respiratory syndrome virus (PRRSV), and bacteria, were carried out. Microscopically, interstitial nephritis with a lymphofollicular inflammatory pattern (follicular nephritis) was observed in both case and control kidneys, with a higher frequency seen in the former ones. No leptospires were identified, although antibodies to the Pomona and Bratislava serovars were detected. Some pyogenic bacteria were also isolated from both case and control kidneys. PCV2 nucleic acid was only detected in 1 case kidney. PRRSV antigen was not found in any tested sample. Some pigs were tested positive for PPV by serology. Apparently, none of the studied agents were specifically associated as being the potential cause of the renal lesions in the studied wasted pigs. The fact that these chronic lesions may have been the consequence of a previous infection with one of these studied microorganisms, or more, and eventually with other non-tested infectious agents during the growing-finishing period, cannot be ruled out.