不同补铁方法对仔猪生长发育的影响试验

比较不同日龄 (3 ,6,9日龄 )补铁、不同补铁剂量和补铁次数对仔猪增重和白痢发病率的影响。结果表明 ,初生仔猪在 3日龄时 ,一次性补铁 1 50mg/头效果较佳 ,35日龄仔猪断奶时增重较 9日龄组和对照组有显著差异 ;一次性补铁 1 0 0mg/头 ,虽能显著提高仔猪增重和降低白痢发病率 ,但其效果不如 1 50mg/头组 (P <0 0 5)。 2次补铁更能充充分发挥仔猪的生长潜力     

饲料中添加腐植酸对仔猪增重及免疫功能的影响

为探讨腐植酸对仔猪增重及免疫功能的影响.本试验选择35日龄健康杜×长×大三元杂交仔猪48头,随机分为4组.每组12头.每组设3个重复.一个对照组,其他3组为试验组(设高、中、低3个剂量组).试验组腐植酸在基础日粮中的添加量分别为1000、100 mg/kg和10 mg/kg,连续饲喂仔猪10 d后,进行称重、T淋巴细胞Ea花环率和B淋巴细胞EAC花环率的测定.结果表明,饲喂腐植酸的健康仔猪高剂量组增重效果显著高于对照组(P＜0.05)中剂量组和高剂量组的Ea花环率显著高于对照组仔猪(P＜0.05);中剂量组的EAC花环率显著高于对照组仔猪(P＜0.05);高剂量组的EAC花环率极显著高于对照组仔猪(P＜0.01).这表明,饲喂高剂量腐植酸可以提高仔猪的增重中剂量和高剂量腐植酸可显著改善仔猪机体的免疫水平.     

饲喂IgG对仔猪血液生化指标和生产性能的影响

试验分两批选用 12 0 ,6 0头大白仔猪 ,出生 2 4h之内饲喂不同剂量的免疫球蛋白制剂 0 ,4 80 ,96 0mg ,均吮食初乳。于仔猪 5 ,10 ,15日龄前腔静脉采血 ,测定血清总蛋白、血清IgG、血清碱性磷酸酶和血红蛋白含量 ,并测定仔猪断奶时增重 ,哺乳前、后期平均日增重。结果表明 :饲喂不同水平的IgG ,仔猪 5 ,10日龄血清总蛋白、血清碱性磷酸酶活性和血红蛋白含量均显著高于对照组 (P <0 0 5 )。饲喂高水平IgG(96 0mg)的仔猪 ,5日龄血清IgG水平显著高于对照组 (P <0 0 5 )。哺乳前期 (0～ 15日龄 )各处理组仔猪平均日增重显著高对照组 (P <0 0 5 ) ,断奶时增重也显著高于对照组 (P <0 0 5 )。     

酵母硒对断奶仔猪生产性能和腹泻的影响

旨在探讨酵母硒对断奶仔猪生产性能和腹泻的影响。选取"杜×长大"断奶仔猪120头,随机分为4组,每组5个重复,每个重复6头。对照组在基础日粮中添加0.3 mg/kg亚硒酸钠,试验1、2、3组的基础日粮中分别添加0.1、0.3、0.5 mg/kg酵母硒,试验期为28 d。试验结束时,测定并比较各组仔猪的试验末体重、日增重、日采食量、料重比、腹泻率和死淘率。结果表明,试验2、3组的试验末体重、日增重、日采食量高于对照组(P0.05),料重比低于对照组(P0.05);试验2、3组的腹泻率低于对照组(P0.05),试验2、3组的死淘率显著低于对照组(P0.05);试验2、3组所有测定指标差异均不显著(P0.05)。提示酵母硒作为有机硒源,能够提高断奶仔猪的生产性能,降低腹泻率和死淘率,综合饲喂效果及生产成本,推荐酵母硒的使用剂量为0.3 mg/kg。     

猪圆环病毒2型灭活疫苗SH株免疫仔猪的田间效力评估试验

本试验选择有猪圆环病毒2型感染,而且已经表现断奶仔猪消耗综合征(PMWS)临床症状的商品猪场(600头母猪)进行试验猪圆环病毒2型(SH株)灭活疫苗的相关研究,以评价猪圆环病毒2型灭活疫苗对仔猪存活率、日增重、病毒血症控制、免疫副反应等指标的变化。试验结果表明:(1)免疫后,免疫组仔猪3周龄断奶时的存活率为91.8%,高于对照组的78.57%;4周龄存活率为98.65%,也高于对照组的90.91%;(2)免疫组在疫苗免疫后1 d体温略有升高,高于对照组,但在第2天后逐步恢复正常;(3)免疫组平均增重为0.2241 kg/头·日;对照组只有0.2052 kg/头·日。免疫组要比对照组多增重0.0189kg/头·日;(4)免疫后免疫组抗体水平转阳率比对照组要高、转阳时间比对照组要早,而且第二次加强免疫后抗体转阳率更高,在49 d全部转阳;并且免疫组离散度小于对照组;(5)免疫疫苗后仔猪群病毒血症阳性率会明显下降,随后与对照组一样,逐步回升,但是,相同日龄的病毒血症阳性率明显低于对照组。上述结果表明,接种猪圆环病毒2型灭活疫苗SH株有助于提高仔猪存活率,提高ADG,改善仔猪生产水平。     

大蒜素对断奶仔猪生长性能的影响

本研究以断奶仔猪为试验对象,研究在断奶仔猪基础饲料中添加不同水平的大蒜素,对其生长性能及腹泻率的影响,并确定大蒜素的最适添加量。试验选择120头21日龄断奶的仔猪按照单因子试验设计,将其随机分为4个处理组,每组30头断奶仔猪。每组断奶仔猪分别饲喂含有0 mg/kg （对照组）、100 mg/kg （试验1组）、200 mg/kg （试验2组）、400 mg/kg （试验3组）的大蒜素基础饲料。预试验期1周,正式试验期4周,试验结束后记录断奶仔猪的平均日增重、料重比、腹泻率等指标。结果显示,试验2组和试验3组断奶仔猪的试验末重显著高于对照组（P<0.05）;平均日增重显著高于对照组（P<0.05）;料重比显著低于对照组（P<0.05）;腹泻率比对照组极显著降低了2.79、3.56个百分点（P<0.01）。综上所述,断奶仔猪养殖生产中添加200 mg/kg的大蒜素可以有效改善其生长性能,并且极显著降低腹泻率。     

圆环病毒攻击下日粮中生物素的添加水平及其对仔猪部分免疫指标及生产性能的影响

本试验旨在确定猪圆环病毒2型(PCV2)攻击下,玉米-豆粕型日粮中生物素的适宜添加水平及其对仔猪部分免疫指标及生产性能的影响.将28日龄断奶、PCV2抗体检测阴性的(杜×长×大)三元杂交仔猪54头,平均分成6个处理,每个处理9个重复,每个重复1头猪.试验第1天试验猪全部口鼻接种PCV2,分别饲喂添加了0、0.10、0.20、0.30、0.40和0.50 mg/kg生物素的日粮,试验期35 d.结果显示:(1)添加0.50 mg/kg生物素时,仔猪35 d的日增重、料重比显著高于0 mg/kg生物素添加组(P<0.05);(2)日粮中添加0.30～0.50 mg/kg生物素,试验第21天和第35天,仔猪血清IgG水平显著高于0～0.20 mg/kg添加组(P<0.05);(3)添加0.30 mg/kg生物素,可以提高试验后期仔猪血清IFN-γ水平;(4)35 d日增重、料重比,以及接种后21和35 d仔猪血清IgG水平与生物素添加量分别呈2次及3次曲线回归.由结果得出,PCV2攻击下,日粮中添加0.30～0.50 mg/kg的生物素,对提高仔猪生产性能,提高IgG及后期IFN-γ水平有良好效果.     

仔猪日粮中添加纳豆芽孢杆菌的效果试验

仔猪日粮中添加纳豆芽孢杆菌进行连续饲喂 ,研究不同添加水平对仔猪日增重、料重比等的影响。结果表明 ,前期试验组仔猪日增重分别较对照组提高 1 2 .31 % (P<0 .0 5)和 1 2 .51 %(P<0 .0 5) ,料重比下降 8.56% (P<0 .0 5)和 6.31 % (P<0 .0 5) ;后期试验组仔猪日增重比对照组分别提高 1 1 .36% (P<0 .0 1 )和 9.1 4 % (P<0 .0 1 ) ,料重比下降 8.70 % (P<0 .0 1 )和 5.93% (P<0 .0 1 ) ,尤以低剂量添加组效果较好     

葡萄糖氧化酶对断奶仔猪生长性能、血清生化指标及经济效益的影响北大核心

试验旨在研究葡萄糖氧化酶对断奶仔猪生长性能、血清生化指标及养殖经济效益的影响。选取200头断奶仔猪,随机分为4组,每组5个重复,每个重复10头断奶仔猪。对照组断奶仔猪饲喂基础日粮,试验组分别在基础日粮中添加50、100、150 mg/kg水平的葡萄糖氧化酶。试验期28 d。结果显示,100 mg/kg组、150 mg/kg组仔猪平均日增重(ADG)显著高于对照组(P<0.05),100 mg/kg组和150 mg/kg组仔猪料重比(F/G)显著低于对照组(P<0.05),各试验组仔猪腹泻率显著低于对照组(P<0.05)。100 mg/kg组仔猪血清总抗氧化能力(T-AOC)和谷胱甘肽过氧化物酶(GSH-Px)活性显著高于对照组(P<0.05),各试验组仔猪血清超氧化物歧化酶(SOD)活性显著高于对照组(P<0.05),100 mg/kg组仔猪血清丙二醛(MDA)含量显著低于对照组(P<0.05)。100 mg/kg组仔猪血清中免疫球蛋白G(IgG)和肿瘤坏死因子-α(TNF-α)含量显著高于对照组(P<0.05),试验组仔猪血清白细胞介素-6 (IL-6)含量均显著高于对照组(P<0.05)。100 mg/kg组、150 mg/kg组仔猪背最长肌IGF-2基因的表达量显著高于对照组(P<0.05)。试验组仔猪养殖利润分别比对照组高7.80、29.28、16.14元/头。研究表明,葡萄糖氧化酶可以提高仔猪生长性能,改善机体健康,建议在断奶仔猪日粮中添加100 mg/kg葡萄糖氧化酶。     

甜菜对早期断奶仔猪的效果试验

将长白猪 (简称长 )×荣昌猪 (简称荣 )杂一代 8窝 30日龄断奶仔猪共计 60头 ,按窝分成 2组 ,实验组和对照组 ,每组各 30头。试验组仔猪料中添加 2 5 %的甜菜根饲喂。对照组饲喂仔猪料 ,试验期为 2 0d,分别记录 30 ,50日龄仔猪空腹重 ,计算日增重。结果表明对早期断奶仔猪补饲甜菜根其腹泻率明显下降 ,试验组日增重较对照组日增重提高 34 .6 % (P <0 .0 1 )。     

Experimental reproduction of postweaning multisystemic wasting syndrome in cesarean-derived, colostrum-deprived piglets inoculated with porcine circovirus type 2 (PCV2): investigation of quantitative PCV2 distribution and antibody responses.

Sixteen cesarean-derived, colostrum-deprived piglets were inoculated intranasally with porcine circovirus type 2 (PCV2), originally isolated from a pig affected with postweaning multisystemic wasting syndrome (PMWS). At 1 day postinoculation (PI), 3 of the 5 piglets in the uninoculated control group were moved to the room of inoculated piglets for contact exposure. Porcine circovirus type 2 was detected by polymerase chain reaction (PCR) in swabs from inoculated piglets from 1 day PI and from contact piglets from 2 days after cohabitation. Porcine circovirus type 2 was also detected in all serum samples but not in control piglets 7 days PI. Until the end of study, PCV2 was detected in swabs and serum samples by PCR but not in the control piglets. One inoculated piglet died suddenly without clinical signs 19 days PI. Beginning at 14 days PI, 5 piglets, including 1 contact piglet, had clinical signs of depression, anorexia, and icterus, and 1 inoculated piglet died 21 days PI. Most of the piglets exhibiting the above clinical signs became moribund and were necropsied 21 and 28 days PI. In the piglets that showed clinical signs, gross lesions, including icterus of liver and hemorrhage in stomach, and typical histopathological lesions of PMWS, such as lymphoid depletion and basophilic intracytoplasmic inclusion bodies in lymph nodes and other tissues, were observed. Porcine circovirus type 2 was detected by PCR in all tissue samples except in those of the control piglets. Porcine circovirus type 2 was recovered from several tissue samples of the piglets necropsied until 35 days PI. In particular, PCV2 was recovered in high titer from most of the tissue samples of the piglets exhibiting clinical signs. Serum antibody against PCV2 was mostly detected in inoculated piglets and in contact piglets 14 and 21 days PI by an indirect fluorescence antibody test but was not detected in the piglets exhibiting clinical signs until 28 days PI. These results indicate that PCV2 was able to induce clinical PMWS in the absence of other swine pathogens and that there were significant differences in both the quantitative PCV2 distribution in tissues and the antibody response between the piglets that were infected and developed PMWS and those that were infected but remained healthy.     

Properties of a Complex of Iron and a Sorbitol-Gluconic Acid Polymer for Treatment of Piglet Anaemia

The properties of a complex of iron and a sorbitol-gluconic acid polymer useful for intramuscular treatment of piglet anaemia have been studied. In rabbits it is well absorbed from muscle and a small percentage (8 %) of the administered iron is excreted in the urine. A satisfactory utilization of the administered iron for haemoglobin synthesis has been shown in rats. A high degree of tolerance in piglets was observed also for the highest test doses, 600 mg iron per kg body weight. The clinical utilization was compared to that of iron-dextran using a total of 209 piglets and a dose of 200 mg iron for each animal. Five of these piglets were lost, but these deaths cannot be correlated to the treatment. Of the remaining animals 102 were treated with ISGP and 102 with iron-dextran, and the anaemia-preventing effect was similar for these 2 iron complexes.     

不同蛋白水平日粮对DLY断奶仔猪生产性能和营养物质消化率的影响

选择30头28日龄断奶的DLY仔猪,平均体重(8.22±0.31)kg,按体重、性别、品种一致原则随机分为3个处理,每个处理10个重复,每个重复1头猪,分别饲喂可消化赖氨酸水平相同,蛋白水平分别为17.0%、19.0%、21.0%的三种不同日粮,考察不同蛋白水平对仔猪生产性能和营养物质消化率的影响。试验结果表明:在氨基酸水平与模式一致时,日粮中蛋白水平对仔猪生长性能没有明显差异,以日粮中蛋白质水平为19%时,乳猪的生长性能最佳。     

Effects of oral doses of corn oil and other factors on preweaning survival and growth of piglets

Piglets were provided supplemental energy as oral doses of corn oil to find whether such treatment might improve survival or weight gains. A total of 1,840 piglets from 182 litters was used. Piglets were allotted to dosed and control treatments within litter on the basis of body weight. Dosed piglets received a total of 8 ml of corn oil in four doses during the first 48 h postpartum. The survival rate to weaning was high and not affected (P greater than .10) by the corn oil doses. Deaths of piglets low in birth weight were delayed by the fat doses, suggesting some utilization. The fat doses did not affect piglet weight gain. Factors affecting preweaning survival and growth of piglets were also evaluated using data from the same piglets. Specific factors investigated were sex, parity of dam, birth weight, litter size and the mean and standard deviation of piglet birth weights within litters. Male piglets were heavier at birth than females, but there was no sex effect on weight at 7 d or at weaning. Small males were less likely to survive to 3 d than were small females. Litters from primiparous sows were smaller at birth and weaning, but had lower percentages of stillbirths and of preweaning deaths than did those from multiparous sows. Piglets from primiparous sows were more uniform in birth weight. Piglets that were heavier at birth grew faster and were more likely to survive. Litter size affected growth but not survival of piglets. A heavier average birth weight in the litter reduced slightly the growth rate of individual piglets. An increase in variability of piglet birth weight within a litter was associated with an increase of the percentages of stillbirths and of preweaning mortality. A few litters accounted for a major portion of the mortality. Much of the variation in piglet mortality and growth was not explained by factors considered.     

猪伪狂犬病病毒双基因缺失gI^-／gE^-／PRV SA738灭活疫苗的安全性与免疫效力

在构建gE和gI双基因缺失猪伪狂犬病毒（Pseudorabiesvirus,PRV）SA738株的基础上,以绿色荧光蛋白为标志,将gI^-／gE^-／PRVSA738转柒BHK-21细胞,通过蚀斑法得到纯化的gI^-／gE^-／PRVSA738。毒价检测结果显示,TCID50由7．25下降至5．75,表明该病毒已被弱化,与预期结果相当。将该病毒灭活后,以不同滴度接种无母源抗体仔猪及妊娠母猪,安全性检测表明,gI^-／gE^-／PRVSA738对仔猪体温、生长,对妊娠母猪产仔及仔猪健康状况均无影响。随后将灭活的gI^-／gE^-／PRVSA738与弗氏佐剂混合乳化,分别接种家兔与仔猪,免疫后7、14、21、28d采血分离血清。经ELISA检测,家兔免疫后14d、仔猪免疫后7d均显示阳性,对照组均为阴性。抗体中和试验表明,家免免疫后14d抗体水平比7d显著升高,但至21d,抗体升高不明显;仔猪抗体水平至28d,中和抗体水平达到1：262．23,与21d相比差异极显著。免疫后28d,采用100LD50 PRV强毒攻击动物,进行免疫保护性试验,结果显示,家兔免疫组只有一只出现轻微的一过性临床症状,未出现死亡,而对照组出现了奇痒等较重的临床症状,且于5d后全部死亡;仔猪对照组攻毒后2d,出现了精神高度沉郁、不食、呕吐与腹泻等症状,并于5d后死亡;免疫组攻毒后3d,出现轻微食欲不振、精神萎靡、腹泻等症状,且于攻毒后6d恢复正常,免疫保护率为100％。以上结果表明,该gI^-／gE^-／PRVSA738-突变株有效诱导了机体的保护性免疫应答。     

叶酸对超早期断奶宫内发育迟缓仔猪肝脏结构和细胞凋亡相关基因表达的影响

本试验旨在研究饲粮添加不同水平叶酸对超早期断奶宫内发育迟缓(IUGR)仔猪肝脏结构和细胞凋亡相关基因表达的影响。选取24头14日龄断奶、平均体重(2.79±0.34)kg的"杜×长×大"三元杂交仔公猪,随机分为3个处理,分别饲喂在基础饲粮中添加0、5和10 mg/kg叶酸的试验饲粮,每个处理8个重复,每个重复1头猪。试验期21 d。结果表明:1)饲粮添加叶酸对35日龄仔猪血清葡萄糖浓度无显著影响(P>0.05),添加5和10 mg/kg叶酸分别显著(P<0.05)和极显著(P<0.01)降低了血清甘油三酯浓度。2)饲粮添加5 mg/kg叶酸能显著降低肝细胞直径(P<0.05)。3)饲粮添加5 mg/kg叶酸显著提高了肝脏B细胞淋巴瘤蛋白2(Bcl-2)的基因表达量(P<0.05),极显著降低了Bcl-2相关X蛋白(Bax)和促凋亡相关基因肿瘤蛋白53(p53)的基因表达量(P<0.01);饲粮添加10 mg/kg叶酸,Bax和p53的基因表达量分别极显著(P<0.01)和显著(P<0.05)地降低了。4)饲粮添加叶酸对肝脏毛细血管扩张性共济失调症突变基因(ATM)、脱嘌呤嘧啶核酸内切酶1(APE-1)基因和一碳单位代谢关键酶编码基因的表达无显著影响(P>0.05)。结果提示,饲粮补充一定水平的叶酸有助于改善早期断奶IUGR仔猪35日龄时肝脏结构和细胞凋亡相关基因Bcl-2、Bax和p53的表达;本试验条件下,饲粮添加5 mg/kg叶酸效果较好。     

Estimation of sow milk nutrient output

Ten replicates of two littermate gilts were used during a 21-d lactation in order to calculate relationships between milk nutrient intake and piglet growth rate and composition of gain. Gilts were fed 14.2 or 10.4 Mcal ME/d and litter size was standardized to 9 or 10 piglets. Piglets had no access to creep feed. Milk production was measured on 10 sucklings over 12 h on d 1, 5, 9, 13, 17 and 21 by the weigh-suckle-weigh method. Heat production of the piglets was measured (RQ method) on the same days in a confinement chamber. Milk composition was determined on the days following milk production measurements. Four to ten piglets/litter were slaughtered at weaning and their body composition was determined. Milk nutrient production during part of lactation was related closely to piglet weight gain and body weight (R2 = .80 to .96). Milk DM, energy and N output over the entire lactation were predicted from piglet ADG (R2 = .87 to .90) when, for each litter, the difference between energy in piglet daily weight gain measured by the slaughter technique and energy in piglet daily weight gain estimated by the RQ method was included in the model. This variable corrects for milk production measurement errors. The relationships were slightly improved, especially for energy output, when the composition of piglet weight gain was taken into account (R2 = .93 to .97).     

An assessment of the most profitable length of lactation for producing piglets of 20 kg body weight

Based on data derived from experiments and surveys carried out in several countries, the most profitable length of lactation for producing piglets of 20 kg body weight is assessed. The assessment is limited to a comparison of the numbers of piglets (20-kg) produced per sow per year at lactation periods varying from 6 to 56 days with the associated amounts of sow and piglet feed consumed and its costs. For the various lactation periods considered, several equations are used to estimate the numbers of 20 kg piglets produced and the amounts and costs of sow and piglet feed consumed per piglet raised to this body weight. According to the assessment, and taking into account reasonable piglet prices, the margins over feed costs per sow per year are highest with a lactation period of 21–25 days.     

益生康代替抗生素对断奶仔猪生产性能及腹泻的影响

试验选用200头平均体重(6.95±0.11)kg、23日龄断奶三元杂交(杜×长×大)仔猪,研究玉米豆粕型日粮中添加益生康代替抗生素在断奶仔猪阶段的应用效果。配对试验设计2个处理,每个处理设5个重复,每个重复20头仔猪,公母各半混合饲养。处理1为抗生素对照组;处理2为添加0.15%益生康组,6～12kg阶段和12～20kg仔猪阶段。结果表明:6～12kg体重阶段与抗生素对照组相比,益生康增加仔猪日增重9.3%,提高日采食量10.6%,改善饲料转化率9.8%,仔猪腹泻发生率降低29.4%(P<0.05);12～20kg阶段日增重提高7.9%,改善饲料转化率15.8%。     

Utilization of milk amino acids by the suckling Iberian piglet

Sixteen pure-bred Iberian (IB) sows were used in two trials to determine the efficiency of utilization of milk protein and amino acid (AA) for growth in suckling piglets. It was hypothesized that there may be one or more strongly limiting essential AA (EAA) responsible for the slow rate of growth of the IB piglet. This AA will show the highest fractional retention. Daily milk yield and composition were determined weekly over a 34-day lactation period. Within each litter, one piglet at birth and four piglets on d 35 of life were slaughtered. The protein content of the IB sow milk was similar to that reported for conventional breeds. However, branched-chain AA, Thr, Pro, Asp and Ala were in concentrations somewhat below the range of literature values and Arg and Met, substantially above it. Milk intake per piglet tended to be greater in Trial 2 (832 vs. 893 g/day respectively; p = 0.066). However, the IB piglets grew at 168 ± 3.3 g/day, irrespective of the trial. The whole-body protein of piglets at weaning and the protein deposited in their body during the lactating period showed very close AA pattern. Among EAA, His and Arg show the highest fractional retentions (g AA retained/g AA ingested) in whole-body tissues (1.019 ± 0.025 and 0.913 ± 0.017 respectively) and also the highest body to milk ratios (1.50 and 1.41 respectively). Gly and Ala presented, among non essential AA, the highest efficiencies of utilization for tissue deposition (1.803 ± 0.057 and 1.375 ± 0.026 respectively) and body to milk ratios (2.75 and 2.12 respectively). These results suggest that the low efficiency of utilization of milk protein and the low rate of gain of the IB suckling piglet can be explained by a marked shortage in His supply, in addition to the suboptimal milk provision of Arg, Gly and Ala.