不同断奶日龄对母羊体况和雌激素分泌的影响

以滩羊为试验动物,采用30 d、45 d、60 d断奶,4月龄断奶为对照。研究结果表明,羔羊的早期断奶有利于母羊产后和断奶后体况的恢复和母羊发情期的提前到来,以30 d断奶母羊体况恢复最佳和对提前母羊的发情期效果最好。     

肉羊的饲养技术

一、繁殖母羊的饲养技术繁殖母羊担负着配种、妊娠、哺乳等繁重任务，应给予良好的饲养，以保证多胎、多产、多活、多壮。繁殖母羊按生理阶段分为空怀期、妊娠期和哺乳期。1．空怀期指以羔羊断奶到母羊再次配种前的时期，也为恢复期，大约3个多月。这时期母羊饲养的重点是抓膘复壮，体况恢复到中等以上。以利配种。中等体况第一发情期受胎率可达80％-85％，体况差的只达到65％-75％。加强母羊配种前一个半月的饲养，尽量选择草质好的草场放牧，延长放牧时间，如草地草质不好，吃不饱时，每只羊每日补饲0．2-0．3kg的混合精料，达到中等以上营养水平，以促进发情。提高受胎率和双羔率。有资料报道，配种前每提高1kg体重，双高率可提高2％．     

滩羊羔早期断奶效果观察

滩羊羔于20、40、90日龄强制断奶,饲喂代乳料,结果表明:20日龄断奶成活率无明显影响(p>0.05),但增重显著低于同龄未断奶羔(p<0.01)和40日龄后断奶羔(p<0.05);40日龄断奶成活率和增重均无明显影响(p>0.05)。滩羊羔40日龄断奶可以使母羊提前100d结束泌乳,尽快恢复体况,从而进入下一繁殖周期、缩短了肥羔生产周期,提高肥羔产量和二毛裘皮产量。     

肉羊的饲养技术

1繁殖母羊饲养技术繁殖母羊担负着配种、妊娠、哺乳等繁重任务,应给予良好的饲养,以保证多胎、多产、多活、多壮。繁殖母羊按生理阶段分为空怀期、妊娠期和哺乳期。1.1空怀期指从羔羊断奶到母羊再次配种前的时期,也为恢复期,大约3个月。这时期母羊饲养的重点是抓膘复壮,体况恢复到中等以上,以利配种。中等体况第一情期受胎率可达80%～85%,体况差的只达到65%～75%。加强母羊配种前一个半月的饲养,尽量选择草质好的草场放牧,延长放牧时间,如草地草质不好,吃不饱时,每只羊每日补饲0.2～0.3千克的混合精料,达到中等以上营养水平,以促进发情,使发…     

母羊断奶后不发情的原因及预防措施

通常情况下母羊断奶后很快就会发情,发情出现时间多为断奶后20d左右,早的15d,最迟25d.母羊断奶后推迟发情或不发情的现象称之为乏情,是指母羊在断奶后20d内不正常发情有的甚至超过30d还未出现发情现象.     

隆林山羊羔羊提前断奶试验

选择隆林山羊羔羊40只,随机分为试验组和对照组.对照组羔羊随母羊分散饲养,30日龄时自然补饲,采取70日龄自然断奶.试验组羔羊10日龄开始采食调教和补饲,50日龄时将母羊隔离,羔羊在原栏断奶,饲养至70日龄.试验结果表明:在圈养条件下对隆林山羊羔羊实行提前人工补饲,提前断奶羔羊的增重差异不显著.而提前断奶组母羊发情率(...     

不同过瘤胃营养添加剂组合对辽宁绒山羊母羊繁殖性能的影响

本试验选取40只胎次、预产期、体重相近的健康妊娠母羊,随机分成4组,试验1、2、3组分别饲喂低、中、高不同水平的过瘤胃添加剂(过瘤胃葡萄糖、过瘤胃胆碱、过瘤胃赖氨酸、过瘤胃蛋氨酸)组合,对照组不饲喂,其他日粮营养水平相同。试验期自妊娠90 d到羔羊90日龄断奶为止,共150 d。试验结果表明:添加过瘤胃添加剂组在妊娠后期和泌乳早期血清E2水平均显著(P0.05)高于对照组,各试验组血清FSH和LH也高于对照组,但泌乳早期差异不显著(P0.05)。试验2组和3组羔羊初生重高于对照组;各试验组羔羊平均日增重均高于对照组,其中试验2组与对照组差异极显著(P0.01)。试验组母羊产后50 d体重均增加,而对照组母羊体重普遍降低,降低比率达到7.16%,表明试验组母羊在产后体况恢复良好。因此在本试验条件下,辽宁绒山羊妊娠母羊日粮中添加低或中等水平的过瘤胃添加剂组合对母羊生殖激素水平、产羔生长性能和母羊体况恢复具有积极作用。     

多产羊羔六项关键技术

春夏秋季是羊发情、繁殖的高峰期,如何发挥公母羊的繁殖潜力,应掌握以下六项关键技术: 1 配种前优饲 配种前1～1.5月给母羊补饲配合饲料,对体况差的母羊要实行优饲,以恢复体况,促进发情。在配种期,对配种任务     

合理淘汰母猪

正首先要淘汰连续2个产次产仔少的母猪,但初次配种体重太轻、妊娠期过度喂饲、哺乳期失重过多、断奶体况差等母猪不包括在内;其次,应淘汰那些用激素处理都不发情的母猪。母猪在断奶后最多应观察18 d,激素处理后应观察7 d,如果这些母猪到下个发情期仍配不上种,则应淘汰;最后,要淘     

母羊补饲不同饲料对哺乳羔羊生长发育的影响

为了探讨青海寒冷地区母羊不同补饲方式对哺乳羔羊生长发育的影响,试验选择产期接近、胎次为3～4胎、经同期发情处理的藏系母羊90只进行了羔羊生长性能和母羊体况测定。结果表明:对生产母羊进行补饲,尤其是在母羊妊娠后期及哺乳期补饲可以明显地增加羔羊的初生重、2月龄重、日增重、初生体尺和2月龄体尺,对母羊自身的体况恢复也有良好的效果。     

不同断奶日龄羔羊瘤胃组织显微及超微结构比较

试验通过比较不同断奶日龄的湖羊羔羊瘤胃组织结构的差异，特别是瘤胃乳头超微结构变化，旨在为羔羊适宜断奶日龄的确定提供瘤胃生长发育的依据。选择新生湖羊羔羊24只（初生重：2.80 kg±0.08 kg），随机分为3组，每组8只，分别为30日龄早期断奶组（EEW-30）、45日龄早期断奶组（EW-45）和60日龄常规断奶组（NW-60）。在各断奶日龄及75日龄时每组分别屠宰4只羔羊，测定体重及瘤胃空重，计算瘤胃相对重量；采集瘤胃组织进行显微及超微形态学测定。结果显示：①EEW-30组羔羊断奶体重极显著低于NW-60组（P<0.01），而EW-45组与NW-60组断奶体重无显著差异（P>0.05）；75日龄时3组羔羊的体重无显著差异（P>0.05）。各组羔羊瘤胃相对重量与其体重变化规律相同。②光镜下可见：断奶时，EEW-30组瘤胃壁厚度极显著低于NW-60组（P<0.01），EW-45组与NW-60组无显著差异（P>0.05）；75日龄时，EW-45组羔羊瘤胃壁厚度显著高于NW-60组（P<0.05）。断奶时EEW-30组瘤胃乳头较短小，极显著短于NW-60组（P<0.01），EW-45组也显著短于NW-60组（P<0.05）。断奶时瘤胃乳头宽度和面积在3组间差异均不显著，在75日龄时也无显著组间差异（P>0.05）。③扫描电镜观测结果显示：EEW-30组断奶时单位面积瘤胃微乳头（ruminal micro-papillae）数量极显著低于NW-60组（P<0.01），而EW-45与NW-60组间无显著差异（P>0.05）；75日龄时，3组羔羊单位面积瘤胃微乳头数量无显著差异（P>0.05）。上述试验结果显示，断奶时羔羊瘤胃形态结构在EEW-30与NW-60组间差异明显，而EW-45与NW-60组较为接近，瘤胃微乳头状结构也呈相同变化趋势。提示45日龄时断奶较为适宜。     

The effect of phenothiazine on cobalt-deficient and cobalt-dosed lambs

The mean serum folate concentrations of Large White sows were compared between one group of 13 animals, 43–80 days pregnant and another group of 9 animals at weaning when the litters were 28–30 days old. The mean concentration was higher in sows at weaning (p<0.05) and the lowest levels were found in sows no more than 51 days pregnant (p<0.05).     

A preliminary investigation of serum folate concentrations in sows during pregnancy and at weaning

The mean serum folate concentrations of Large White sows were compared between one group of 13 animals, 43-80 days pregnant and another group of 9 animals at weaning when the litters were 28-30 days old. The mean concentration was higher in sows at weaning (p<0.05) and the lowest levels were found in sows no more than 51 days pregnant (p<0.05).     

Effect of Different Weaning Ages on Main Digestive Enzymes Activities in the Small Intestinal Contents of Lamb

The objective of this study was to determine the effects of different weaning ages on pH and the main digestive enzymes activities in the small intestinal contents of lamb. Fifty-five male lambs of Gansu modern breeding sheep group with(3.43±1.15)kg initial body weight were divided into 3 treatments randomly that were control group (sucking,25 lambs), group Ⅰ (weaning at 28 days old, 15 lambs), and group Ⅱ(weaning at 42 days old,15 lambs).5 lambs from each group were slaughtered at 12 h,7 d and 14 d after weaning,respectively,and the the change of pH and activities of α-amylase,trypsin,chympotrypsin and lipase were measured in the small intestinal contents. The results showed that the effects of pH and the main digestive enzymes activities could be expressed sensitively in the contents of duodenum. From duodenum to ileum,the effects of weaning turned weakening gradually,and it did not show a high-impact on pH,trypsin and lipase activities. There was no significant influence in the recovery time to the normal levels of the main digestive enzymes activities in the small intestinal contents by different weaning ages,the recovery time of α-amylase in group Ⅰ was shorter than group Ⅱ. In this trail condition,it was feasible to wean at 28 days of age,and it had no significant difference in the recovery ability of main digestive enzymes in the small intestinal contents weaning at 28 and 42 days old.     

断奶日龄对舍饲羔羊小肠内容物中主要消化酶活性的影响

为研究早期断奶日龄对羔羊小肠各段pH及主要消化酶活性的影响,选用55只初生重为（3.43±1.15）kg的甘肃现代肉羊育种群哺乳公羔,按同质原则分成3组,即对照组（正常吮乳组,25只）、Ⅰ组（28日龄断奶组,15只）和Ⅱ组（42日龄断奶组,15只）。在断奶12 h、7 d和14 d后从每个处理中随机抽取5只羔羊屠宰,测定小肠各段pH、α-淀粉酶、胰蛋白酶、糜蛋白酶和脂肪酶活性变化。结果显示,十二指肠食糜能够更为敏感地表达断奶对小肠pH及主要消化酶活性的影响。从小肠近端至远端,断奶对各肠段内容物pH及主要消化酶活性的影响逐渐减弱;断奶对小肠内容物pH、胰蛋白酶活性和脂肪酶活性影响较小;断奶日龄对羔羊小肠主要消化酶活性恢复所需要的时间影响不大,28日龄断奶组小肠α-淀粉酶活性恢复时间较42日龄断奶组短。本试验条件下,对羔羊实施28日龄断奶可行,且羔羊小肠主要消化酶活性恢复能力不逊于42日龄断奶羔羊。     

基于Meta分析早期断奶对羔羊生长性能的影响

本研究基于Meta分析评估早期断奶对羔羊生长性能的影响。采用计算机检索数据库辅助手动搜索文献,按文献排除标准共纳入30篇文献,试验组为994头早期断奶羔羊,对照组为539头随母哺乳羔羊,以肉羊60日龄体重和胸围作为生长性能指标,分别收集了1413只肉羊体重数据和1011只肉羊胸围数据,通过回归分析后亚组分析解释异质性来源,敏感性分析评价合并效应量后结果稳定性,漏斗图评估文献发表偏倚。Meta分析结果表明:早期断奶对羔羊60日龄体重无不良影响(P=0.225),回归分析发现,早期断奶对羔羊60日龄体重的影响与断奶日龄有关,与随母哺乳羔羊相比,羔羊30~40日龄断奶补饲能显著提高60日龄体重(P<0.001)。早期断奶对羔羊60日龄胸围无显著影响(P=0.282)。敏感性分析显示分析结果稳定可信,漏斗图显示纳入的文献存在一定的发表偏倚。     

饲养管理对哺乳仔猪成活率与断奶重的影响

将60头八眉猪二元待产母猪随机分成实验组和对照组,每组30头,实验组在预产期前30d在母猪的饲料中添加适量的营养物质,基础喂量为每天每头2kg,每产一头仔猪增加0.25kg,仔猪生出后1～3日龄保温箱的温度控制在30～32℃,4～7日龄为28～30℃,8～28日龄圈舍温度控制在22 ～ 25℃.对照组产前30d在饲料中不添加含蛋白质饲料,每天每头饲喂3.5kg.仔猪出生1～7日龄保温箱的温度控制在28 ～30℃,8～28日龄分娩舍温度控制在20～25℃.结果表明,实验组28日龄成活率和断奶重明显高于对照组,差异均显著（P＜0.05）.     

断奶日龄对仔猪断奶期腹泻和死亡影响的研究

选择杜洛克×豫农白猪Ⅰ系杂交仔猪８窝共７２头，均分为两组，每组４窝３６头。试Ⅰ组采用２８日龄断奶，试Ⅱ组采用３５日龄断奶。试验期从断奶前１周至６０日龄，分析比较不同断奶日龄对仔猪断奶期腹泻和死亡的影响。结果：①试Ⅰ组和试Ⅱ组仔猪，断奶后至６０日龄间发生腹泻１５９头次和８５头次，全群日平均腹泻发生率为１４．７６％和９．０８％；②试Ⅰ组和试Ⅱ组仔猪，断奶后至６０日龄间死亡数为４头和０头；③试Ⅰ组和试Ⅱ组仔猪，断奶后至６０日龄发生腹泻的高峰期在断奶后５～２２天和断奶后３～８天，持续期为１８天和６天，日腹泻发生率最高达４２．４２％和３３．３３％；④试Ⅰ组４窝仔猪在断奶至６０日龄期间，有３窝出现多个腹泻高峰，只有１窝为１个高峰；而试Ⅱ组４窝仔猪中，只有１窝出现多个腹泻高峰，其它３窝为１个高峰。     

The effect of two different weaning procedures on the growth of pasture-reared Thoroughbred foals in New Zealand

AIM: To identify if there was a significant difference in the average daily liveweight gain (ADG) between Thoroughbred foals weaned using two weaning protocols commonly used in New Zealand.

METHODS: Sixteen Thoroughbred foals were blocked for sex and age, randomly allocated into progressive (187, SD 33 days; three colts, five fillies) or abrupt (182, SD 28 days; four colts, four fillies) weaning groups, and weighed every second day for 2 weeks either side of weaning, then fortnightly from birth to 480 (SD 31) days old. ADG was calculated to examine the short-term (10 days before weaning, 5 and 10 days post weaning) and long-term (0–6 and 6–16 months of age) effect of the two weaning treatments.

RESULTS: ADG was 1.10 (SD 0.091) kg/day before weaning (0–6 months of age) and 0.59 (SD 0.06) kg/day from weaning to 480 (SD 31) days old. At the start of weaning, liveweights of the progressive and abrupt weaning groups were 276.5 (SD 40.3) kg and 257 (SD 15) kg, respectively (p=0.23). For the 5-day period during weaning, irrespective of treatment, there was a significant decrease in ADG of –0.29 (SD 0.49) kg/day and –0.15 (SD 0.30) kg/day for progressive and abrupt weaning, respectively. There was no significant difference in ADG between weaning methods at any measurement period (short or long term) during and after weaning. However, there was large variation between foals in ADG in the 10 days after the weaning process, which may indicate variation in individual foals' responses to being weaned, rather than the weaning treatment.

CONCLUSIONS: Weaning, irrespective of method, was associated with a decrease in ADG in the first week after weaning. The method of weaning had no effect on post-weaning ADG either short term, 10 days after weaning, or long term up to 480 days of age. Practically, it may be more important to consider maturity and liveweight as criteria for weaning foals rather than age alone.