猪某些免疫指标及其与部分性状关系的研究

实验测定了哈白、杜洛克猪３月龄和５月龄的总数Ｅ－玫瑰花环形成细胞百分率、活性Ｅ－玫瑰花环形成细胞百分率、淋巴细胞转化率、血清ＩｇＧ含量及５月龄接种布氏杆菌猪型二号苗后７、２１、３５ｄ的特异性抗体滴度，对这些免疫指标及其与部分生产性状的关系进行了分析，旨在为猪的抗病育种提供依据。实验结果表明：（１）３月龄和５月龄几个免疫指标均存在品种差异，哈白猪显著地高于杜洛克猪；（２）３月龄与５月龄间所测细胞免疫     

鸡眼区相关淋巴组织对ND疫苗的点眼免疫应答 Ⅰ.局部体液免疫应答

本研究采用 Ｅ Ｌ Ｉ Ｓ Ａ、免疫组织化学方法、病理组织学方法对鸡眼区相关淋巴组织在鸡新城疫（ Ｎｅｗ ｃａｓｔｌｅ Ｄｉｓｅａｓｅ， Ｎ Ｄ）疫苗点眼免疫后的局部体液免疫应答进行了研究。研究发现， Ｌａｓｏｔａ 系 Ｎ Ｄ 疫苗点眼免疫后鸡眼区相关淋巴组织（ Ｈｅａｄａｓｓｏｃｉａｔｅｄ Ｌｙｍ ｐｈｏｉｄ Ｔｉｓｓｕｅ， Ｈ Ａ Ｌ Ｔ）对 Ｎ Ｄ 疫苗可产生高效的局部体液免疫应答：①免疫组泪液和血清中 Ｎ Ｄ Ｖ特异性 Ｉｇ Ａ、 Ｉｇ Ｍ 抗体及哈氏腺（ Ｈａｒｄｅｒｉａｎ Ｇｉａｎｄ， Ｈ Ｇ）中 Ｉｇ Ａ、 Ｉｇ Ｍ 型浆细胞出现较对照组早，且抗体滴度及浆细胞数量均极显著高于对照组（ Ｐ＜ ０．０１）。免疫组泪液和血清中 Ｎ Ｄ Ｖ特异性 Ｉｇ Ｇ 抗体滴度及哈氏腺中 Ｉｇ Ｇ 型浆细胞数量也均极显著高于对照组（ Ｐ＜ ０．０１），且哈氏腺中 Ｉｇ Ｇ 型浆细胞的出现早于对照组；②点眼免疫后泪液中 Ｎ Ｄ Ｖ特异性 Ｉｇ Ａ、 Ｉｇ Ｍ抗体出现较血清中的早，且抗体滴度也显著高于血清中（ Ｐ＜ ０．０５）；③ Ｌａｓｏｔａ 系 Ｎ Ｄ苗点眼免疫后可使结膜相关淋巴组织的形成和发育明显提前，免疫组结膜相关淋巴组织中的淋巴滤泡数量极显著高于对照组（ Ｐ＜ ０．     

MD疫苗免疫雏鸡vMDV攻击后体液免疫球蛋白含量的变化

本实验以马立克氏病（ＭＤ）三价苗（ＳＢ＿１＋８１４＋ＨＶＴ）和ＨＶＴ疫苗免疫１日龄肉用雏鸡，１５日龄时腹腔注射马立克氏病强毒（ｖＤＭＶ）进行攻击，在攻毒后５、２５、４５和７５天用间接ＥＬＩＳＡ法测定实验雏鸡血清、泪液、气管液、胆汁和肠液ＩｇＧ、ＩｇＭ和ｌｇＡ含量的动态变化，结果发现免疫雏鸡强毒攻击后，其血清、泪液和气管液的ＩｇＧ、ｌｇＭ和ＩｇＡ含量显著高于感染对照鸡，胆汁和肠液中ＩｇＡ以及ＩｇＧ、ＩｇＭ显著高于感染对照鸡，其中三价菌免疫鸡的３种免疫球蛋白含量明显高于ＨＶＴ免疫鸡；表明ＭＤ强毒攻击后，免疫雏鸡全身和消化道、呼吸道局部的体液免疫应答显著增强，三价苗免疫鸡的体液免疫反应明显高于ＨＶＴ免疫鸡，并与其较高的免疫保护率相关。     

免疫调节剂对球虫感染鸡的免疫学指标的影响

为探讨免疫调节剂对鸡球虫病的免疫反应调节作用，设计并进行了免疫调节剂对球虫感染鸡的免疫学指标的影响的研究。测定指标包括：淋巴细胞玫瑰花环细胞形成率、淋巴细胞转化率、红细胞免疫复合物花环形成率、红细胞Ｃ３ｂ受体花环形成率、脾脏重／体重相对重；血清中ＩｇＧ，ＩｇＭ，ＩｇＡ的ＥＬＩＳＡＰ／Ｎ值。试验结果表明：胸腺素、黄芪多糖和卡介苗等免疫调节剂可提高球虫感染鸡的淋巴细胞玫瑰花环形成率、淋巴细胞转化率。     

补铁对仔猪免疫功能的影响（摘要）

采用醋酸纤维薄膜电泳法和氚—胸腺嘧核苷掺入法（３Ｈ—ＴｄＲ），研究了补铁对仔猪免疫功能的影响。对参试仔猪检测了两项免疫学指标和三项血常规，结果显示；出生后给予补铁的仔猪，３２日龄时的血清丙球蛋白（ｒ—Ｉｇ）水平及外周血淋巴细胞转化能力均明显高于不补铁对照组（Ｐ＜０．０１），其中对淋巴细胞转化能力的影响更为显著；缺铁性贫血仔猪经补铁治疗后血常规指标明显改善，外周血淋巴细胞３Ｈ—ＴｄＲ掺入量显著提高（Ｐ＜０．０１），而血清ｒ—Ｉｇ的平均值与不治疗对照组差异不显著（Ｐ＞０．０５），这提示对初生仔猪注铁后的体液免疫和细胞免疫均获得提高，不予补铁则发生缺铁性贫血，从而严重影响了仔猪的免疫功能，其中对细胞免疫功能的影响更为显著。     

兔病毒性出血症蜂胶佐剂组织灭活苗的免疫效果

用ＰＭＶＲＶＨＤ和ＶＲＶＨＤ分别免疫家兔，用Ｅ－玫瑰花环形成试验测定细胞免疫水平（Ｔｃ），用微量血凝抑制试验（ＨＩ）进行体液免疫水平测定。并于免疫后期（第１６５ｄ和第１８７ｄ），用ＲＶＨＤ强毒对不同家兔分别进行攻击试验。结果发现：ＰＭＶＲＶＨＤ组（Ａ组）家兔Ｅ－玫瑰花环形成率显著高于ＶＲＶＨＤ组（Ｂ组）（Ｐ＜０．０１）；Ａ组家兔血清ＨＩ值极显著地高于Ｂ组（Ｐ＜０．０１）。同时，试验组家兔的细胞免疫先于体液免疫出现。在第１８７ｄ的攻击试验中，Ａ组家兔全部健活，Ｂ组家兔死亡２只，其余５只则有不同程度的发热表现。结合细胞免疫和体液免疫的测定结果，认为ＰＭＶＲＶＨＤ对家兔的免疫效果比ＶＲＶＨＤ更好。     

干燥布氏菌苗免疫对奶牛Ea玫瑰花环形成及产奶量的影响

泌乳奶牛经干燥布氏杆菌活菌苗加强免疫，第3周观测到Ea玫瑰花形成率明显下降（P＜0．01），后来回升。第9周，Ea玫瑰花率显著高于注射菌苗前及对照组（P＜0．01）。试验期间受试组奶牛泌乳平均单产和每周总产量显著高出对照（P＜0．01）。试验结果表明，重复注射干燥布氏杆菌活菌苗可提高机体非特异性细胞免疫水平，在增强奶牛抗感染的同时，促进乳腺泌乳机能。     

雏鸡感染马立克氏病病毒后体液免疫球蛋白含量的变化

以马立克氏病病毒（ＭＤＶ）感染１日龄肉用雏鸡，在感染后５、２５、４５ｄ分别采取血清、泪液、胆汁、气管液和肠液，用间接酶联免疫吸附试验检测了这些体液中ＩｇＧ、ＩｇＭ和ＩｇＡ含量的动态变化。结果如下：ＭＤＶ感染雏鸡血清中ＩｇＧ、ＩｇＭ和ＩｇＡ含量较对照组显著降低，胆汁和肠液中的ＩｇＡ、ＩｇＧ和ＩｇＭ明显减少，泪液和气管液中的ＩｇＧ、ＩｇＭ和ＩｇＡ水平也显著下降。由此表明，ＭＤＶ感染不仅显著降低雏鸡全身体液免疫水平，而且也严重抑制消化道和呼吸道局部体液免疫机能。     

不同月龄鸵鸟38项血液生化参数比较

比较了 １～３ 月龄（ ｎ ＝ １５）和 ４～６ 月龄（ ｎ ＝ １５）鸵鸟血液的 ３８ 项生化参数。结果，１～３ 月龄和 ４～６ 月龄鸵鸟之间血清 Ｃ Ｋ、 Ｔ Ｇ、 Ｂ Ｕ Ｎ、 Ｂ Ｕ Ｎ／ Ｃ Ｒ Ｅ、 Ｕ Ａ、 Ｍ ｇ、 Ｐ含量差异极显著（ Ｐ ＜ ００１）；血清 Ｔ Ｂ Ａ、 Ｌ Ｄ Ｌ Ｃ、 Ｃ Ｈ Ｏ、 Ｔ Ｔ Ｔ、 Ｎａ、 Ｋ 含量的组间差异显著（ Ｐ ＜ ００５）；其他指标 ２ 组间差异不显著。该结果提示，不同月龄鸵鸟的营养物质代谢过程存在一定差异。     

雏鸡感染马立克氏病病毒后免疫器官组织抗体生成细胞的变化

以马立克氏病病毒（ＭＤＶ）感染１日龄肉用雏鸡，在感染后５、２５、４５ｄ采取法氏囊、脾脏、盲肠扁桃体和哈德尔腺，用彩色免疫金银染色法检查免疫器官组织中ＩｇＧ、ＩｇＭ和ＩｇＡ抗体生成细胞数量的动态变化。结果：ＭＤＶ感染雏鸡的法氏囊、脾脏和哈德尔腺中以ＩｇＧ抗体生成细胞居多，ＩｇＧ、ＩｇＭ和ＩｇＡ抗体生成细胞均较正常对照鸡显著减少；盲肠扁桃体中以ＩｇＡ抗体生成细胞居多，ＩｇＡ、ＩｇＧ和ＩｇＭ抗体生成细胞数量显著低于正常对照鸡。由此表明，ＭＤＶ感染鸡全身免疫器官和消化道、呼吸道局部粘膜体液免疫机能明显抑制。     

不同猪种5-羟色胺受体基因的表达及其与肉质的相关性分析

为研究5-羟色胺（5-HT）受体基因在不同猪种的表达及其与肉质的关系,试验选取淳安花猪与杜长大三元猪各12头,同时饲喂,达上市体重时分别屠宰,测定胴体、肉质性状及肌肉、脂肪中的5-HT受体基因表达量。结果表明：淳安花猪、杜长大三元猪的平均屠宰体重分别为88.1、102.4kg;淳安花猪的板油率、背膘厚、肌内脂肪等指标均显著高于杜长大三元猪（P〈0.05）;屠宰率、眼肌面积杜长大三元猪显著高于淳安花猪（P〈0.05）。5-HT2A、5-HT7受体基因在2个猪种脂肪组织中的表达量均显著高于肌肉组织（P〈0.05）,杜长大三元猪的肌肉中5-HT2A、5-HT7表达量显著低于淳安花猪（P〈0.05）,而脂肪中表达量两猪种间差异不显著。5-HT2A、5-HT7受体基因表达量与屠宰肉质指标之间基本呈负相关,尤其是肌肉中的5-HT2A表达量,呈较强负相关（杜长大三元猪）或显著负相关（淳安花猪）。研究初步认为,5-HT受体基因在中外猪种之间存在表达差异,并与屠宰肉质性状具有相关性。     

Evaluations of Boar Gonad Development,Spermatogenesis with regard to Semen Characteristics,Libido and Serum Testosterone Levels based on large White Duroc × Chinese Erhualian Crossbred Boars

Chinese Erhualian pigs are known for prolificacy with distinct reproductive traits compared with Western commercial breeds. In this study, a four‐generation intercross resource population was constructed using White Duroc boars and Chinese Erhualian sows as founder animals, and a total of 14 male reproductive traits were recorded in 411 F₂/F₃ boars including the testis and epididymis weights, the seminiferous tubular diameter and spermatogenesis at 60, 90 and 300 days of age, semen characteristics, serum testosterone concentration and libido level at 300 days of age. The White Duroc–Erhualian boars showed remarkable segregations in the traits measured except for the seminiferous tubular diameter and had high ratio (13.9%) of the abnormality of spermatogenesis, providing a good experimental population for detecting quantitative trait loci affecting these male reproductive traits. Furthermore, the correlations among nine male reproductive traits at 300 days of age indicated that the testis weight and the body weight were strongly correlated with the sperm production, supporting the two traits as important parameters for boar selection to increase sperm production and ultimately improve boar fertility. The libido level in the White Duroc–Erhualian boars that was evaluated by a new and easily recorded scoring system showed a significant correlation with serum testosterone concentration. Yet, both libido and serum testosterone concentration were not correlated with the sperm production. Results of this study provided new information on the male reproductive physiology and genetics in Chinese Erhualian and White Duroc boars.     

杜洛克、大白、长白猪的生长和肉用性状杂交效果研究

为筛选优化杂交组合,进行了杜洛克（杜）、大白（大）、长白（长）品种间杂交试验,测定了不同品种组合的生长速度、饲料转化率、胴体和肉质性状及其杂种优势率。结果表明,杜洛克、父系大白猪作终端父本与长大杂母猪杂交,其后代的日增重、饲料转化率、屠宰率、胴体长、眼肌面积、后腿比例、瘦肉率及肉质等主要性状均无显著差异。     

Evidence of breed-dependent differences in susceptibility to porcine circovirus type-2-associated disease and lesions

Porcine circovirus type 2 (PCV2) has been confirmed as the primary cause of postweaning multisystemic wasting syndrome (PMWS). However, in the field, PMWS is seen only in a small percentage of pigs infected with PCV2. The overall objective of the study reported here was to determine whether host genetic differences in the susceptibility to PCV2-associated disease exist among selected breeds of pigs. This study included Duroc (n = 23), Landrace (n = 19), and Large White (n = 21) pigs. The pigs were infected intranasally and intramuscularly at 5-7 weeks of age with PCV2. A portion of the pigs (31/63; 30.2%) had low passively acquired PCV2 antibodies at the time of infection. There were no differences in mean weight gain, rectal temperature, or respiratory score. Clinical disease compatible with PMWS was observed only in the Landrace pigs. Most of the PCV2-infected pigs had enlarged lymph nodes, and individual Duroc and Landrace pigs had mottled tan lungs. PCV2-associated lymphoid depletion and granulomatous inflammation were observed in pigs of all breeds. Three of 19 Landrace pigs and none of the Duroc or Large White pigs developed severe lymphoid lesions associated with large amounts of intralesional PCV2 antigen typical of PMWS. Compared with seronegative Landrace pigs, Landrace pigs that had low maternal antibodies at the time of PCV2 inoculation had significantly (P < 0.05) less-severe PCV2-associated lesions. The results suggest a predisposition of the Landrace pigs of this study to PCV2-induced disease and lesions, and that low levels of passively acquired antibodies are protective.     

猪SLA-DRA基因外显子2多态性及其与仔猪腹泻的关联分析

为探索SLA-DRA基因作为猪抗病育种分子标记的可能性,本研究采用PCR-SSCP和克隆测序方法对大白、长白和杜洛克共216头猪的SLA-DRA基因外显子2进行了多态性研究,分析了该基因与仔猪腹泻的关联性。结果,在SLA-DRA外显子2上检出了3个等位基因和6种基因型;6种基因型(AA、AB、BB、AC、BC和CC)在大白猪和长白猪中都存在,而在杜洛克猪中只检出4种基因型(AA、BB、AB和BC)。杜洛克猪与大白猪和长白猪间基因型分布均差异极显著(P<0.01);3个品种的基因型分布均处于Hardy-Weinberg平衡状态(P>0.05)。最小二乘法分析表明,品种和性别对仔猪腹泻影响不显著(P>0.05),基因型与仔猪腹泻显著相关(P<0.05);AA和BB基因型个体腹泻评分的最小二乘均值均显著高于AC和CC基因型个体(P<0.05)。本研究表明,SLA-DRA基因不同基因型对仔猪腹泻有着重要的影响,可作为猪抗病育种应用中的一个潜在遗传标记。     

Effects of Duroc, Meishan, Fengjing, and Minzhu boars on productivity of mates and growth of first-cross progeny.

Meishan, Fengjing, Minzhu, and Duroc boars were mated by AI to crossbred gilts to compare the sire breeds for effects on productivity of their mates and performance of their progeny. Gilts were derived from a four-way cross of Chester White, Landrace, Large White, and Yorkshire. At weaning, litters sired by Meishan boars averaged 1.69 and 1.32 more pigs than those sired by Duroc and Minzhu boars, respectively (P less than .05). Pigs sired by Meishan and Fengjing boars averaged 1.2 to 1.8 more nipples than pigs sired by Duroc and Minzhu boars (P less than .05). Minzhu-sired pigs had a lower (P less than .05) survival rate to 14 and 28 d of age than did those sired by Meishan, Fengjing, and Duroc. Fengjing-sired pigs were heavier than Minzhu-sired pigs at birth and heavier than Minzhu- and Duroc-sired pigs at 14, 28, and 56 d of age (P less than .05). At 70 d of age, Meishan-sired pigs were heaviest, followed in order by Fengjing-, Duroc-, and Minzhu-sired pigs. At 98 d of age, Meishan-sired pigs were significantly heavier than all other breed groups and Duroc-sired pigs were significantly heavier than Minzhu-sired pigs. At 126 and 154 d of age, Duroc-sired pigs were heaviest, followed in order by Meishan-, Fengjing-, and Minzhu-sired pigs; all differences were significant. Average backfat thickness of gilts at 99.7 kg was least for Duroc-sired gilts and highest for Meishan-sired gilts. Sire breed groups did not differ significantly in feed efficiency from 70 to 98 d of age. Duroc-sired pigs were the most efficient (P less than .05) from 98 to 126 and 126 to 154 d of age. Results indicate that use of these Chinese breeds in crossbreeding programs will decrease performance traits. This decrease would have to be offset by increases in reproductive efficiency of Chinese sows, use of repartitioning agents, or other management techniques if Chinese pigs are to improve overall production efficiency of a crossbreeding program.     

品种、季节、胎次、采精月龄及采精间隔对猪精液品质的影响

【目的】探究品种、公猪出生胎次、公猪同窝仔猪数、公猪乳头数、采精季节、采精月龄和采精间隔对猪精液品质的影响,以及不同品种对精液质量稳定性的影响。【方法】选取909头杜洛克、长白、大白种公猪为试验群体,收集2021年4月至2022年4月27 408条精液测定记录,采用混合线性分析模型和方差分析探究品种、公猪出生胎次、公猪同窝仔猪数、公猪乳头数、采精季节、采精月龄和采精间隔对精液体积、精液密度、精子活力、直线前进运动精子比例、精子畸形率、总精子数及各精液性状稳定性的影响。【结果】从不同品种对精液品质的影响来看,长白猪精液体积和总精子数均显著高于大白猪、杜洛克猪(P＜0.05),杜洛克猪精液密度显著高于大白猪和长白猪(P＜0.05),杜洛克猪、大白猪精子活力均显著高于长白猪(P＜0.05),大白猪直线前进运动精子比例显著高于长白猪和杜洛克猪(P＜0.05),长白猪和大白猪精子畸形率均显著低于杜洛克猪(P＜0.05);从不同公猪出生胎次对精液品质的影响来看,1~3胎出生的公猪具有较高的精液品质;从不同采精季节对精液品质的影响来看,精液密度、精子活力和总精子数秋、冬季显著高于春、夏季(P＜0.05);从不同采精月龄对精液品质的影响来看,16~25月龄公猪具有较高的精液品质;从不同采精间隔对精液品质的影响来看,4~5 d为最佳采精间隔,采精间隔过长会导致精子畸形率上升;从不同公猪总乳头数来看,乳头数13~16个时,各精液性状品质都处于中等水平,有利于公猪生产应用。3个品种各精液性状间稳定性趋势不一,杜洛克猪和大白猪精液体积和精子活力的稳定性均显著高于长白猪(P＜0.05),杜洛克猪精液密度、精子畸形率和总精子数的稳定性均显著高于大白猪和长白猪(P＜0.05),大白猪直线前进运动精子比例的稳定性显著高于长白猪和杜洛克猪(P＜0.05)。各品种中,长白猪稳定性较差;各精液性状中,精子活力稳定性最好。【结论】品种、公猪出生胎次、采精季节、采精月龄和采精间隔均会影响公猪精液品质,可根据不同品种公猪制定更完善的选择方案,提高精液质量,加速公猪遗传改良。     

Differential electrocardiographic study on Iberica and Duroc breeds of pig during physical maturation

Sequential electrocardiograms were taken of 50 pigs (25 Iberica and 25 Duroc), from the ages of 5 days to 205 days. The records were analysed to establish the normal values of the different electrocardiographic intervals (RR, QRS, QT, TQ and ST intervals), the diastole/systole quotient and heart score in the first 7 months of life, as well as age-related electrocardiographic variations. In addition, it was intended to determine which of these two breeds showed the greater heart recovery capacity. Finally, positive or negative correlations between the RR interval and the electrocardiographic incidents studied were analysed. The mean values obtained for the electrocardiographic parameters were similar in the two breeds and increased with their physical maturity. Analysis of the correlation between the duration of the heart cycle and the different electrocardiographic incidents showed a positive and significant correlation, the r-values being higher for the RR interval-TQ interval correlation. There was very little correlation between RR interval and heart score in Duroc pigs and practically no correlation between the RR interval and the QRS interval in either breed.     

不同品种、月份、月龄及采精间隔对猪精液品质的影响

为研究不同品种、采精月份、采精月龄和采精间隔等因素对加系公猪精液品质的影响,以及品种、初次采精周龄对精液质量稳定性的影响,本研究以江西某种公猪站79头加系大白猪、长白猪、杜洛克猪种公猪为试验群体,收集2018年12月至2020年12月3 921条精液采集与精液质量数据,通过混合线性模型与方差分析探究各因素对精液量、精液密度、精子活力、总精子数及其稳定性的影响。结果显示,从不同品种对精液质量的影响来看,长白猪精液量和总精子数均高于大白猪、杜洛克猪,但杜洛克猪精液密度高于长白猪、大白猪,杜洛克猪精子活力最低;从不同月份来看,1~3月采精精液密度最高,4~6月采精精子活力最高,10~12月采精精液量和总精子数最高,精液量呈现秋冬多、春夏少的季节变化规律。公猪不同月龄采精,精液质量指标也存在差异,月龄越小精液量越低,但精液密度偏高,精子活力相对较好,在19~24月龄黄金期总精子数最高。不同采精间隔对精液质量有较大影响,采精间隔越长,精液量、精液密度、精子活力和总精子数相对较好,采精间隔为5 d时综合性能最佳,但过长的采精间隔导致精子活力降低。品种影响总精子数稳定性,长白猪、大白猪总精子数稳定性显著优于杜洛克猪（P<0.05）。本研究结果表明,品种、采精月份、采精月龄和采精间隔均会影响公猪精液质量,关注这些因素有助于公猪站制定更完善的生产计划,提高公猪利用率。     

军牧1号白猪、杜洛克猪和藏猪的H-FABP 和LPIN1基因多态性分布

为探索H-FABP和LPIN1基因在不同猪种中的多态性分布情况,应用PCR-RFLP技术检测了61头军牧1号白猪、51头杜洛克猪和51头藏猪H-FABP和LPIN1基因的多态性分布。结果发现,军牧1号白猪、杜洛克猪和藏猪在H-FABP基因的Hinf Ⅰ多态性位点上均表现为单一的HH型,而Hea Ⅲ多态性位点上均表现出多态性,等位基因D的基因频率分别为0.1475、0.2255和0.7647,Msp Ⅰ多态位点上,军牧1号白猪表现为单一的aa型,杜洛克猪和藏猪则表现为多态性,等位基因A的基因频率分别为0.6078和0.4609。在LPIN1基因的Eco88 Ⅰ多态性位点上,杜洛克猪表现为单一的AA型,军牧1号白猪和藏猪表现为多态性,等位基因A的基因频率分别为0.4262和0.2059;在Bsh1236 Ⅰ多态性位点上,杜洛克猪表现为单一的TT型,军牧1号白猪和藏猪则表现为多态性,等位基因T的基因频率分别为0.7459和0.2059。