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1.
长链多不饱和脂肪酸(LC PUFAs)在母猪营养中的作用经常被人们研究,因为猪场的盈利能力主要取决于母猪的繁殖性能。根据以往的研究结果,母猪妊娠期喂食ω-3 LC PUFAs可以减少前列腺素的合成,提高胚胎存活率和仔猪初生重;哺乳期饲喂ω-3 LC PUFAs可以提高乳汁中EPA和DHA含量,改善哺乳仔猪肠道健康和断奶重。文章论述了LC PUFAs(主要是ω-3)对现代高产母猪繁殖性能的影响,为在生产实践中合理添加应用LC PUFAs,提高母猪生产性能提供理论参考。  相似文献   
2.
Escherichia coli is a natural colonizer of the urogenital mucosa of healthy females; however it is one of the pathogens associated to reproductive failures in cows and sows. A better knowledge about the characteristics of native E. coli will allow us to differentiate them from pathogenic strains. Ninety autochthonous isolates from the reproductive tract of sows and cows were characterized to determine the phylogenetic profile, antibiotic resistance and virulence factors; also, comparisons between different breeding systems were performed. Vaginal colonization of E. coli was statistically higher in cows (57.5%) than sows (23.8%), and most isolates belonged to the phylogenetic group A: 79.69 and 80.77%, respectively; moreover phylo-groups B1 (12.5 and 11.54%) and D (7.81 and 7.69%) were significantly lower; however, none was classified as B2. Positive associations between virulence factors and group D were found. Isolates with antimicrobial susceptibility were associated with group A and the MDR (Multiple Drug Resistance) was related to the porcine source. These results contribute to the knowledge of extra-intestinal E. coli populations; which could affect the reproductive performance of females.  相似文献   
3.
The objective of this study was to evaluate the effects of supplemental magnesium (Mg) on the performance of gilts and parity 3 sows and their piglets. Fifty-six gilts (Trial 1) and 56 sows (Trial 2) were assigned to one of 4 treatments according to their mating weight, respectively. The treatments comprised corn-soybean meal based gestation and lactation diets (0.21% magnesium) supplemented with 0, 0.015, 0.03, or 0.045% Mg from mating until weaning. The results showed that magnesium supplementation significantly (P < 0.05) reduced the weaning to estrus interval in both gilts and sows. There were significant effects (P < 0.05) of supplemental magnesium on the total number of piglets born, born alive and weaned in sows. In late gestation and lactation, the digestibility of crude fiber (quadratic effects, P < 0.05), and crude protein (P < 0.05), were significantly influenced by magnesium in gilts and sows, respectively. There were differences among the 4 groups in terms of the apparent digestibility of dry matter and crude fiber in sows (P < 0.05) during both early and late gestation. The apparent digestibility of gross energy was increased for sows in late gestation (P < 0.05), and lactation (quadratic effects, P < 0.05). At farrowing and weaning, serum prolactin levels and alkaline phosphate activities linearly increased in sows as the Mg supplementation increased (P < 0.05). Serum Mg of sows at farrowing and serum urea nitrogen of sows at weaning was significantly influenced by Mg supplementation (P < 0.05). The Mg concentration in sow colostrum and the serum of their piglets were increased by supplemental magnesium (P < 0.05). In addition, growth hormone levels were linearly elevated (P < 0.05) in the serum of piglets suckling sows. Our data demonstrated that supplemental magnesium has the potential to improve the reproduction performance of sows, and the suitable supplemental dose ranged from 0.015% to 0.03%.  相似文献   
4.
母猪无乳综合征(MMA)是母猪乳腺炎(Mastitis)、子宫炎(Metritis)和无乳症(Agalactia)的简称,是由多种原因引起的母猪产后泌乳量逐渐减少甚至是完全无乳,以致于哺乳仔猪乳汁摄入量不足,严重影响到仔猪的生长发育。MMA在猪场中经常发生,尤其是在炎热的夏秋季节多发,母猪一旦发生MMA,就会影响到仔猪的成活率,从而给猪场带来经济损失。许多饲养母猪的猪场对MMA都比较熟悉,有研究表明,规模猪场中哺乳仔猪死亡因素的50%都与MMA有关。那么,是什么原因导致了母猪MMA问题?MMA的发生现状又如何?一旦发生,猪场该如何应对?怎么样进行防治?本篇文章主要介绍了英国颇为高产(已发表近3000篇关于养猪的文章)的养猪专栏作家John Gadd,结合他本人过去几十年来在世界各地猪场的宝贵经历,写成的介绍母猪MMA的最新文章。  相似文献   
5.
Antioxidant defence of colostrum and milk in consecutive lactations in sows   总被引:1,自引:0,他引:1  

Background

Parturition is supposed to be related to oxidative stress, not only for the mother, but also for the newborn. Moreover, it is not clear whether consecutive pregnancies, parturitions, and lactations are similar to each other in regards to intensity of metabolic processes or differ from each other. The aim of the study was to compare dynamic changes of antioxidative parameters in colostrum and milk of sows taken during 72 h postpartum from animals in consecutive lactations. Activities of glutathione peroxidase (GSH-Px), glutathione transferase (GSH-Tr), and superoxide dismutase (SOD), and amount of vitamin A and C were measured. Healthy pregnant animals were divided into 4 groups according to the assessed lactation: A -1st lactation (n = 10), B - 2nd and 3rd lactation (n = 7), C - 4th and 5th lactation (n = 11), D - 6th - 8th lactation (n = 8). The colostrum was sampled immediately after parturition and after 6, 12, 18 and 36 h while the milk was assessed at 72 h after parturition. Spectrophotometric methods were used for measurements.

Results

The activity of antioxidative enzymes and the concentration of vitamin A increased with time postpartum. The concentration of vitamin C was the highest between the 18th and 36th h postpartum.

Conclusions

Dynamic changes in the values of antioxidant parameters measured during the study showed that sows milk provides the highest concentration of antioxidants in the 2nd and 3rd and 4th and 5th lactation giving the best defence against reactive oxygen species to newborns and mammary glands.  相似文献   
6.
Mortality of sows is a major problem for pig production worldwide. In this study, we used hierarchical multivariable logistic analyses to investigate different risk factors for mortality at the sow and herd level in herds with group-housed pregnant sows. Data included 3652 pregnant and 1266 lactating sows from 34 sow herds. A clinical examination for 16 clinical signs was carried out for each sow, and information about 16 herd related factors was obtained by interviews. Farm records were used to obtain information about whether or not sows died suddenly or were euthanized within 3 months after the clinical examination. Factors increasing the risk of sow mortality in the gestation unit were solid pen floors (OR = 1.87), presence of vulva bites (OR = 1.73) and unwillingness to stand when approached (OR = 1.62). Factors increasing the risk of sow mortality in the lactation unit were pale vulva color (OR = 12.69), body leanness (OR = 4.11), and presence of shoulder ulcers (OR = 2.89). The estimated between herd variation was small. Thus, the findings for the sow level variables may be generally applicable for sows in herds with group housed systems.  相似文献   
7.
The present study was conducted to evaluate non-return rate (NR), farrowing rate (FR), and number of total pigs born/litter (TB) of weaned sows after intra-uterine insemination (IUI) using low numbers of frozen–thawed (FT) spermatozoa. Semen from 6 boars was cryopreserved individually in a 0.5-ml straw, at a concentration of 1 × 109 spermatozoa/ml. A total of 40 multiparous sows with weaning-to-estrus interval of 3 to 7 days were included. The sows were detected for standing estrus twice daily and randomly assigned to two groups: I) spontaneous ovulation (n = 20) and II) induced ovulation (n = 20) which the sows were given 750 IU human chorionic gonadotrophin (hCG) i.m. immediately at estrus detection. Ovulation was determined every 12 h using transrectal ultrasonography. FT semen containing 1 × 109 motile spermatozoa/dose was used to IUI. In group I, the sows were inseminated at 24 h after the detection of estrus and repeated every 12 h until ovulation. In group II, the sows were inseminated at 36, 42 and/or 48 h after hCG treatment. The results showed that the interval from standing estrus to ovulation (EOI) differed significantly between group I (40.2 h) and group II (35.6 h; P = 0.01). Variation of EOI among sows within each group seemed to be lower in group II (4.5 h SD) than in group I (5.5 h SD; P = 0.5). The number of IUI per sow was 2.9 ± 0.6 times in group I and was 2.4 ± 0.5 times in group II. There were no significant differences (P > 0.05) in the NR (80 vs 85%), FR (60 vs 65%) and the TB (8.0 ± 2.8 vs 9.4 ± 3.7 piglets/litter) between the groups. These results indicated that multiple doses of IUI with a low number of FT boar spermatozoa provided a fairly good NR, and reasonable FR and TB both in spontaneous and induced ovulating sows. The number of inseminations required for attaining acceptable fertility tended to be lower in the weaned sows with induced ovulation.  相似文献   
8.
用PMSG +LH、维生素D3,维生素E对乏情母猪进行试验处理 ,结果表明 ,PMSG +LH、维生素D3,维生素E联合使用 ,效果最好  相似文献   
9.
Heat stress has detrimental effects on lactating sows and their litters, including decreased feed intake and milk production in sows and decreased weight gain in their offspring. It also increases respiration rate, rectal temperature, and weaning to estrus interval in sows. This study was conducted to investigate the effects of chilled water (CW) on the performance of lactating sows and their litters exposed to high ambient temperatures for 21 days. Ninety multiparous sows (Yorkshire × Landrace; parity range: 2 to 5) and their litters (Yorkshire × Landrace × Duroc) were divided into 3 blocks (30 each). Sows and their litters within each block were randomly assigned to one of the three treatment groups (n = 10 each). Each group was provided with drinking water at 10, 15, or 22 °C (control) under farm conditions where ambient temperature above 25 °C was consistent during the experimental period. Sows on CW (both 10 and 15 °C) consumed more feed and water than did control (P < 0.01) and higher estimated milk production compared with control (P < 0.01), but had lower rectal temperature and respiration rate compared with control (P < 0.01). Mean weaning weight (P < 0.01) and average daily gain (P < 0.01) of litters in CW groups were higher than those in control group. There were no differences in the measured variables, with the exception of the respiration rates, between the two CW treatment groups. These results suggest that CW may improve the performance of sows and their litters exposed to high ambient temperatures and the 15 °C water, from an energy viewpoint, may be more effective.  相似文献   
10.
为了研究复合中草药添加剂对母猪生产性能的影响,选择体况健康,无疾病,胎次一致,配种时间接近的三元杂交母猪30头,随机分为3组,对照组(基础饲粮),试验Ⅰ组(抗生素组,每吨成品添加50g,15%含量金霉素)、试验Ⅱ(0.5%中草药组,每吨成品添加中草药5kg)每组2个重复,每个重复5头猪,测定记录乳猪生长性能及母猪的繁殖性能。结果表明:试验Ⅱ组20及28日龄断奶窝重分别比对照组提高19.31%,10.64%差异显著(P<0.05),比试验Ⅰ组分别提高6.94%,3.32%差异显著(P<0.05);0-28日龄平均窝日增重试验Ⅱ组比对照组提高12.57%差异显著(P<0.05);乳猪出生后1-7天的腹泻指数试验Ⅱ组比对照组及试验Ⅰ降低37.37%,17.33%,差异显著(P<0.05);断奶后7天的发情率试验Ⅱ组对照组及试验Ⅰ组分别提高9.58%,8.04%,差异显著(P<0.05)。综合表明:中草药可以替代抗生素使用提高母猪的生产性能  相似文献   
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