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21.
The effects of two enzyme (Enz) products on ileal and total tract digestibility (ID and TTD) were evaluated in sows (n = 8) fed corn–soybean meal diets. Treatments were: 1) control diet; 2) control + Enz 1 (protease and cellulase activity); and 3) control + Enz 2 (xylanase activity). Ileal and fecal samples were collected at week 6–7 and 12–13 of gestation and week 2–3 of lactation. There were no improvements in digestibility during gestation. The ID% of dry matter (DM: 77.3, 79.3, 81.7) and N (81.2, 82.5, 84.3) as well as TTD% of DM (89.8, 90.7, 90.8) and N (89.0, 90.0, 90.6) during lactation were affected to varying degrees by the enzymes. The TTD of DM (P = 0.05) and N (P = 0.10) were positively affected by Enz 1. The ID of DM (P = 0.01) and N (P = 0.02) as well as TTD of DM (P = 0.05) and N (P = 0.02) were improved by Enz 2. The improvement in ID of N was not associated with any particular amino acids (AA) but represented small increases in ID of 8 of 10 essential AA with Enz 1 (P = 0.04) and 10 of 10 for Enz 2 (P = 0.01). The product containing xylanase activity, in particular, appears to have potential to increase digestibility of nutrients during lactation in sows.  相似文献   
22.

The concentrations of vitamin E, glutathione peroxidase (GSH-Px) and retinol were analysed in blood plasma of six primiparous sows during gestation and lactation and in their suckling piglets, and the concentrations of vitamin E, selenium and retinol were analysed in colostrum and in sows' milk. During late gestation the concentrations of vitamin E and retinol in blood plasma increased slowly while no changes were found for GSH-Px. This was followed by a large decline on the day of farrowing, when the lowest mean values of 1.07 mg, 0.15 mg and 2879 U per litre (l) of blood plasma, respectively, were recorded. During lactation the concentrations of vitamin E, GSH-Px and retinol in blood plasma of the sows increased to levels observed during late gestation. The highest mean concentrations of vitamin E (17.9 mg kg- 1 ), selenium (200 w g l- 1 ) and retinol (2.45 mg kg- 1 ) were found in colostrum, but with a large variation between sows. One week postpartum the concentrations of vitamin E, selenium and retinol in sow milk had decreased, on average by 86, 68 and 71%, respectively, after which only small changes occurred. Mean concentrations of vitamin E (1.77 mg l- 1 ), GSH-Px (682 U l- 1 ) and retinol (0.07 mg l- 1 ) were low in the blood plasma of the piglets at birth, but a large increase was observed on the next sampling occasion at the age of 3 days (vitamin E: 5.31 mg l- 1 ; GSH-Px: 996 U l- 1 ; retinol: 0.19 mg l- 1 ). The mean concentration of vitamin E in blood plasma of the piglets declined thereafter until the age of 6 weeks (1.04 mg l- 1 ), when there was a small increase, while the mean concentrations of GSH-Px and retinol continued to increase during the suckling period. A high correlation was found between the concentration of vitamin E in blood plasma and sidefat thickness of the sows (r = 0.94), and between the concentration of vitamin E in colostrum and vitamin E in blood plasma of the sows on the day of farrowing (r =0.77). High correlations were also found between the concentration of vitamin E in the blood plasma of the piglets at 3 days and 5 weeks of age and the concentration of vitamin E in colostrum (r = 0.78) and (r =0.89), respectively. The results indicate that vitamin E storage in the adipose tissues of the sow has a great influence on the supply of vitamin E via colostrum and milk to the piglet.  相似文献   
23.
周波 《猪业科学》2021,38(11):34-37
近期猪价的大幅持续下跌,让养猪企业再次尝到了持续亏损的痛苦。文章介绍了生猪价格周期(猪周期)的特点和产生原因,并说明了顺猪周期进行养殖规模的调整对于减少商品猪养殖企业亏损的重要性。举例说明了顺猪周期进行能繁母猪数的减少和增加,可减少低猪价期的亏损。介绍了如何利用终端轮回杂交繁育体系在四年一轮回的猪周期踏准节奏进行商品猪的生产。还比较了杜长大三级繁育体系与终端轮回杂交繁育体系的区别,介绍了终端轮回杂交繁育体系的优势、对猪育种的影响和应用前景。  相似文献   
24.
    
The effects of adding potassium diformate (K-diformate) to diets for primiparous and multiparous sows (Dutch × Scandinavian Landrace) (n = 156) were evaluated with respect to performance of sows and their litters, apparent total tract digestibility (TD) of nutrients, milk composition, and microbiota of sows' feces. Treatments comprised a basal diet and a basal diet containing 0.8 or 1.2% K-diformate. The experiment lasted from mating, through gestation and lactation until the next mating. Sows were fed restrictively according to a commercial feeding regime during the gestation period, and had free access to feed from d 10 post-farrowing. The addition of K-diformate to diets increased backfat thickness (P = 0.03) of sows during gestation. No effects on average daily feed intake or body weight gain were seen. Piglets born to sows receiving K-diformate tended to have increased individual (P = 0.05) and litter (P = 0.08) birth weight, tended to have increased average daily gain (ADG) (P = 0.07) and to be heavier at weaning (P < 0.05). Birth weights, ADG, and weaning weights were similar for piglets born from sows fed 0.8 and 1.2% K-diformate. There was no effect of K-diformate on the number of pigs born alive, number of stillborns or mortality rates of piglets. Adding 1.2% K-diformate to diets increased TD of ash by 4.9% (P = 0.001) and crude fat by 3.4% (P = 0.08), and calculated NE-content by 2.3% (P = 0.02). Sows fed K-diformate tended (P = 0.09) to show an increased milk fat content on d 12 post-farrowing. In conclusion, adding K-diformate to diets for sows had a positive effect on sows' backfat thickness in gestation and on growth performance of piglets.  相似文献   
25.
楼房猪场可节约占地面积,楼房猪舍常增设新风过滤装置和排风除臭墙用以改善舍内环境和减少废气排放。为了解此类楼房猪舍夏季环境控制情况,选择北京郊区某楼房猪舍的三个楼层作为监测对象,底层(1层)、中间层(3层)和顶层(5层)新风过滤装置洁净度分别为优、差和良,中间层和顶层风机开启6台,底层风机开启5台,通过监测猪舍的温度、湿度和二氧化碳浓度(质量分数)、风机处静压差等环境参数,分析楼房猪舍不同楼层通风量、温度、温度分布均匀度及环境舒适度。结果显示,底层、中间层和顶层风机处静压差分别为69.7、110.1和98.7 Pa;高静压差导致猪舍实际通风量和风机能效比降低,猪舍实际通风量中间层(205 313 m3/h)和顶层(233 611 m3/h)显著低于底层(247 903 m3/h)(P<0.05),风机能效比中间层(15.3 m3/(h·W))和顶层(17.4 m3/(h·W))显著低于底层(22.5 m3/(h·W))(P<0.05);底层舍内温度(24.2 ℃)显著低于中间层(24.6 ℃)和顶层(24.7 ℃)(P<0.05),舍内不同位置同期最大温差(0.4 ℃)显著低于中间层(1.1 ℃)和顶层(0.6 ℃)(P<0.05),综合温湿度和风速计算母猪等效温度指数(Equivalent Temperature Index for Sows,ETIS),底层最小,中间层最大。该研究可为楼房猪舍提高通风效率、优化楼房猪舍夏季环境控制方案提供理论依据。  相似文献   
26.
不同胎次大约克夏母猪的繁殖性能观察   总被引:3,自引:0,他引:3  
观察大约克夏母猪10个胎次,每胎次40窝,发现其断奶至发情配种天数,从第九胎开始有明显减少;产仔数从第八胎开始明显降低;产活仔数、初生窝重从第七胎开始明显下降;断奶数及断奶窝重从第六胎开始明显降低。因此,大约克夏母猪的淘汰,一般应从第六胎开始  相似文献   
27.
28.
Sow removal in Swedish commercial herds   总被引:3,自引:0,他引:3  
The objective of this study was to describe the sow removal pattern in Swedish commercial piglet producing herds, with group-housing of non-lactating sows. The data collection, based on a PC herd monitoring program used in 21 piglet producing herds in the south-central part of Sweden, was prospective, started in 2002 and continued for 3 years. During this period, information on 14 234 removed sows was recorded. For all parameters studied a large variation between herds was found. The average annual removal rate was 49.5% (range 33.6–66.3%). Among the removed sows, 85.2% were sent to slaughter, 10.5% were euthanised and 4.3% were found dead. The most common removal reasons were ‘reproductive disorders’ (26.9%), ‘old age’ (18.7%) and ‘udder problems’ (18.1%), followed by ‘low productivity’ (9.5%), ‘lameness and/or foot lesions’ (8.6%) and ‘traumatic injuries’ (7.1%). The proportion of sows sent to slaughter was higher than the proportion euthanised for all categories of removal except ‘traumatic injuries’ (in which 81.6% of the sows were euthanised). The average parity number at removal for all sows was 4.4. Lowest average parity numbers were found for sows removed due to ‘traumatic injuries’ (2.6). Among removed sows, the proportion removed per parity decreased up to parity 6. Sows removed due to ‘old age’ had the highest piglet production, while sows removed due to reproductive disorders had the highest number of non-productive days (NPD) per parity and the longest interval from last farrowing to removal. With increasing removal parity number, the number of piglets produced increased and NPD decreased. In lower parities (1–3) most sows were removed due to ‘reproductive disorders’, but this proportion fell as parity number rose. Removals due to ‘udder problems’ were most frequent in medium parity numbers (4–6). Most sows removed after parity 7 were removed due to old age. The proportion of the sows found dead was highest just after farrowing; otherwise only a low percentage of sows were removed during the lactation period. The proportion of euthanised sows was high in the week after farrowing and during the 4-week period following weaning. The proportion of sows sent to slaughter increased considerably 4 weeks after farrowing (i.e. after weaning) and stayed high during the subsequent 3 weeks. The study revealed a considerable amount of unplanned removal of young sows. Not only the sows sent to slaughter, but also those euthanised and found dead, must be included in studies on sow removal.  相似文献   
29.
氨基酸铁络合物对新生和哺乳仔猪铁营养状况的影响   总被引:9,自引:0,他引:9  
用24头已与杜洛克父本配种的妊娠70天的(长×大)杂交母猪及其所生的24窝仔猪进行试验,研究不同铁源与注射铁剂补铁对新生和哺乳仔猪铁营养状况的影响。试验分为妊娠和泌乳两个阶段,均采用完全随机设计。在妊娠阶段,将妊娠70天的杂交母猪24头随机分为3个处理组,分别饲喂添加80mg/kg铁源于硫酸亚铁的玉米 豆粕 小麦麸型饲粮(正对照组)和在正对照组饲粮基础上添加120mg/kg铁源于氨基酸铁络合物的饲粮(有机铁组),以及在正对照组饲粮基础上添加120mg/kg铁源于硫酸亚铁的饲粮(无机铁组)。在泌乳阶段,泌乳母猪继续饲喂以上妊娠母猪的相应处理饲粮,而对来源于以上24头母猪的24窝新生仔猪,则设置成另外3个饲粮铁处理组,即来源于以上正对照组母猪的哺乳仔猪饲喂未添加铁的玉米 豆粕 干乳清粉 鱼粉型基础饲粮开食料(负对照组),来源于以上有机铁组母猪的哺乳仔猪饲喂在负对照组基础上添加120mg/kg铁源于氨基酸铁络合物的饲粮开食料(有机铁组),和来源于以上无机铁组母猪的哺乳仔猪饲喂在负对照组基础上添加120mg/kg铁源于硫酸亚铁的饲粮开食料(无机铁组)。每窝仔猪中有一半于出生后的第1天内以葡萄糖酸铁形式一次性注射100mg铁,另一半则不注射铁。哺乳仔猪于出生后的第5天开始喂给开食料,直到27日龄断奶结束。结果表  相似文献   
30.
[目的]探讨地衣芽孢杆菌菌剂和菌粉对妊娠及哺乳母猪生产性能和猪舍氨气浓度的影响。[方法]选用产前30 d的妊娠母猪(长×大)为试验对象,通过在基础日粮中分别添加地衣芽孢杆菌菌剂和菌粉,考察其对妊娠及哺乳母猪生产性能和猪舍氨气浓度的影响。[结果]与对照组相比,饲喂地衣芽孢杆菌后能显著降低母猪便秘率、仔猪腹泻率及猪舍氨气浓度,且对母猪采食量及仔猪死淘率等也有明显改善。[结论]在饲料中添加地衣芽孢杆菌能有效提高母猪及仔猪的生长性能,改善猪舍环境,降低污染。  相似文献   
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