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1.
Four experiments involving 265, 410, 894, and 554 sows (Exp. 1 to 4, respectively) were conducted to determine the effect of spray-dried plasma (SDP) at 0 or 0.25% (Exp. 1 and 2) and 0 or 0.50% (Exp. 3 and 4) in lactation diets on average daily feed disappearance (FD), sum of sow BW, fetal and placental loss from d 110 gestation to weaning (SWL), litter size at weaning, litter weight at weaning, and average days from weaning to first estrus (WEI). Experiments 1, 3, and 4 were conducted during summer months, and Exp. 2 was conducted during fall to winter months. Experiment 1 used only parity 1 and parity 2 sows and Exp. 4 used only mature (>2 parities) sows, whereas Exp. 2 and 3 used all parity groups. Sows fed SDP in Exp. 1 had increased (P < 0.01) FD and a tendency for reduced (P = 0.06) SWL and WEI (P = 0.06). Sows fed SDP in Exp. 2 had a tendency for increased (P = 0.09) sow BW at weaning and reduced (P = 0.09) SWL, whereas other variables were not different between diets. Parity 1 and 2 sows fed SDP in Exp. 3 had increased (P < 0.01) FD, but mature sows fed SDP had reduced (P = 0.02) FD. Pig survival and litter size at weaning for all parity groups was not different between diets. The WEI for parity 1 sows fed SDP was reduced (P = 0.02) and tended to be reduced (P = 0.10) for mature sows fed SDP, but was not different between diets for parity 2 sows. More parity 1 sows fed SDP were detected (P = 0.01) in estrus 4 to 6 d after weaning, and fewer were detected (P < 0.01) in estrus 6 d after weaning compared with control parity 1 sows. In Exp. 4, FD was reduced (P < 0.01) for mature sows fed SDP; however, litter weight and average pig BW at weaning was increased (P < 0.01) with more (P < 0.01) marketable pigs (pig BW > 3.6 kg) weaned per litter. Relatively low dietary levels of SDP (0.25 to 0.50%) fed to parity 1 sows farrowed during summer months increased lactation FD and reduced WEI. Mature sows fed SDP during summer months consumed less lactation feed without compromising WEI, but had an increased litter weight, average pig BW, and number of marketable pigs at weaning.  相似文献   

2.
Sows from five commercial herds were weaned in the fall and winter and used to ascertain the potential application of hormonal therapy to stimulate subsequent litter size born. At weaning sows within parity (1, 2, and 3 through 6) and lactation length classification (early weaned, < or = 14 d; conventionally weaned, > 14 d) were randomly assigned to treatment. Treatments were injection with P.G. 600 (400 IU PMSG with 200 IU hCG) at weaning or no treatment. Sows were individually observed for estrus and mated following protocol for each herd. Breeding, culling, and farrowing data were collected. Treatment with P.G. 600 did not change subsequent rebreeding performance for sows at parity 1 or parities 3 through 6. However, conventionally weaned parity-2 sows treated with P.G. 600 were more likely (P < .05) to return to estrus than conventionally weaned controls (99.0 vs 93.6%, respectively). For parity-1 and parity-2 sows, treatment did not significantly change the likelihood for farrow percentage. However, the likelihood to farrow a litter was greater (P < .05) among P.G. 600-treated sows at parities 3 to 6 that were conventionally weaned (84.4 vs 71.3%, respectively). Subsequent litter birth weight for parity-1 sows treated with P.G. 600 was lower (P < .02) than for controls (15.6 vs 16.6 kg, respectively). Subsequent litter size at birth was not affected by treatment for parity-1 or parity-2 sows compared with controls. However, early-weaned sows at parities 3 through 6 treated with P.G. 600 had more (P < .06) total number born than controls (12.4 vs 10.6, respectively). Treatment with P.G. 600 improved reproductive function within specific parity and lactation length classification for sows weaned in the fall and winter.  相似文献   

3.
The impact of diet deprivation and subsequent over-allowance in prepubertal gilts on their mammary development and mammary gene expression at the end of gestation and their lactation performance over 2 parities was determined. Seventy-seven gilts were reared under a conventional (control, CTL; n = 41) or an experimental (treatment, TRT; n = 36) dietary regimen. The experimental regimen provided 70 (restriction diet, RES) and 115% (over-allowance diet, OVER) of the protein and DE contents provided by the CTL diet. Experimental diets were fed ad libitum starting at 27.7 ± 3.4 kg of BW as follows: 3 wk RES, 3 wk OVER, 4 wk RES, and 4 wk OVER. All gilts were bred, and 34 were slaughtered on d 110 of gestation (18 CTL and 16 TRT) to collect mammary tissue for compositional analyses and gene expression measurements. Remaining gilts (23 CTL and 20 TRT) were maintained for 2 parities, and litter performance data were obtained. Blood samples for hormonal and metabolite assays were obtained on d 110 of gestation from all sows slaughtered at that time and from 14 sows per treatment on d 2 and 17 of lactation in the first parity. Milk samples were obtained from these same sows on d 17 of lactation in both parities. There was a tendency for mammary parenchymal tissue to contain less protein in TRT than CTL sows (P < 0.10), and relative mRNA abundance of the signal transducer and activator of transduction 5B gene was increased in parenchyma from TRT sows (P < 0.05). Circulating prolactin (P < 0.05) and milk lactose concentrations (P < 0.01) were less, whereas milk protein content was greater (P < 0.05) in TRT sows than CTL sows on d 17 of lactation. Nevertheless, growth rate of suckling piglets over the first 2 parities was unaffected by treatment. In conclusion, the use of a diet deprivation and over-allowance regimen in the growing-finishing period did not have beneficial effects on mammary gene expression or on sow and piglet performance.  相似文献   

4.
为了研究胎次对杜洛克、长白和大白母猪繁殖性能的影响,根据江苏省某国家级生猪核心育种场2009-2011年出生的繁殖母猪资料,分别选取128头杜洛克、681头长白和610头大白母猪共7280窝生产数据,统计分析不同胎次母猪的总产仔数、产活仔数、断奶仔猪数、初生窝重及校正21日龄窝重。此外,依据胎次将母猪分为3个繁殖阶段(1~2胎、3~6胎及7~8胎)来探究品种差异对母猪繁殖性能的影响。结果表明:胎次对母猪繁殖性能有显著影响(P<0.05),母猪1~4胎的总产仔数、产活仔数、断奶仔猪数及初生窝重随胎次呈增加趋势,第4胎达到高峰,且显著高于其他胎次(P<0.05);3~6胎繁殖性能较好,7胎之后出现迅速下降趋势;除在第4胎略有下降外,其他胎次的校正21日龄窝重随胎次递增。品种对母猪繁殖性能的影响显著(P<0.05),长白和大白母猪的繁殖性能均极显著高于杜洛克母猪(P<0.01);长白母猪的产活仔数和校正21日龄窝重显著高于大白母猪(P<0.05),2个品种其他繁殖性能无显著差异(P>0.05)。综上所述,杜洛克、长白和大白母猪的最佳繁殖胎次为3~6胎,长白猪的繁殖性能总体上优于大白猪,就本试验所在的育种场而言,长白猪可能更适合作为二元母猪生产中的母本。  相似文献   

5.
Forty-two sows were used to determine the effects of adding a Saccharomyces cerevisiae fermentation product (SCFP) to the gestation and lactation diets on the performance of sows and their progeny. At 5 d before breeding, sows were allotted to 2 dietary treatments representing 1) sows fed a diet with 12.0 g of fermentation product/d through gestation and 15.0 g of fermentation product/d through lactation (SCFP treatment, n=22), and 2) sows fed a diet with equal amounts of a mixture of corn and soybean meal instead of the SCFP (CON treatment, n=20). Sow BW and backfat thickness were recorded. Blood was collected from sows, as well as piglets, for the measurement of cell numbers, plasma urea nitrogen (PUN), and IgG. Fecal samples from d 7 to 9 of lactation were collected to determine apparent total tract nutrient digestibility. The composition of colostrum and milk was also measured. No difference (P > 0.10) in reproductive performance was observed between treatments. However, sows in the SCFP treatment tended to have increased total litter weaning weight (P=0.068) and litter BW gain (P=0.084) compared with sows in the CON treatment. Neutrophil count was decreased (P < 0.05) by adding the fermentation product on d 110 of gestation and d 17 of lactation, whereas a decreased (P < 0.05) white blood cell count was observed only on d 110 of gestation. Concentration of PUN tended to be greater (P=0.069) for sows in the CON treatment compared with sows in the SCFP treatment on d 110 of gestation. Apparent total tract nutrient digestibility values of ash, CP, DM, and ether extract were not affected (P > 0.10) by adding the fermentation product. Protein and fat contents in colostrum and milk did not differ (P > 0.10) between treatments. Colostrum from sows in the SCFP treatment contained a greater (P < 0.05) amount of ash than colostrum from sows in the CON treatment. Immunoglobulin G measured in the colostrum, milk, and plasma of piglets did not differ (P > 0.10) between sows in the CON and SCFP treatments. This study indicates that adding the SCFP in the gestation and lactation diets has the potential to 1) improve litter BW gain during lactation, possibly by improving maternal protein utilization, as shown in a tendency to reduce PUN; 2) improve the maternal health status, as shown by the reduced neutrophil cell count; and 3) increase milk production, as shown in a tendency to improve litter BW gain without affecting nutrient composition of the colostrum and milk.  相似文献   

6.
The aim of this study was to investigate the effect of dietary fibre on reproductive performance during the first two parities. Gilts were randomly allocated to receive three fibrous diets from days 1-90 of gestation, including low fibre [low fiber (LF), 10.8% neutral detergent fiber (NDF), n=132], middle fibre [middle fiber (MF), 15.8% NDF, n=132] and high fibre diet (HF, 20.8% NDF, n=135), until completion of the second parity. Response criteria included backfat measurements, litter size and pig weight at parturition and day 22 of lactation, weaning-oestrus-interval, oestrus rate, sow farrowing and culling rate, uniformity of newborns and relative organ weights. The results showed sows fed LF diet in parity 1 gained more backfat (p<0.05) during gestation but lost more (p<0.05) during lactation than sows fed HF diet. Furthermore, sows fed LF diet farrowed more pigs (+0.7-1.1 pigs, p<0.05) and pigs born alive (+1.0 pigs, p<0.05) relative to sows fed HF diet. Likewise, sows fed LF and MF diets had greater litter weights at parturition (both p=0.06) and day 22 after lactation (both p<0.05). In parity 2, yet, it was MF diet to increase both total pigs born and pigs born alive (+0.9-1.1 pigs, p<0.05) and litter weight (p=0.05) relative to other diets. After 22 d of lactation, intriguingly, sows fed HF diet had most pigs alive (p<0.01-0.07) and heavier litter weight (p=0.07 or 0.2). Feeding HF diet also increased internal organs weight of newborns (p<0.05). Collectively, feeding LF and MF diets had beneficial effects on litter weight at parturition and day 22 of lactation in parity 1, and feeding MF diet until parity 2 was able to improve litter size and weight at parturition, but this positive effect disappeared after 22 days of lactation, instead feeding HF diet showed the optimal litter performance.  相似文献   

7.
To determine the effectiveness of a single injection of vitamin A to increase litter size, 1,375 sows were assigned randomly to 11 treatment groups (125 sows per treatment). Treatments included injection of 1 x 10(6) IU of vitamin A dissolved in corn oil at weaning or on d 0, 2, 6, 10, 13, 19, 30, 70, or 110 after breeding. Sows in the control group were injected with corn oil on corresponding days. A total of 396 sows were removed from the study following treatment or treatment assignment. Therefore, farrowing data were collected for 979 sows. Injection of vitamin A did not influence (P > . 10) total litter size, live litter size, litter weight, pig weight, number of runts, or number of mummies. Mean live litter size was 10.1 +/- .1 for all sows that farrowed in the experiment. Parity group affected total litter size, live litter size, live litter weight, and number stillborn (P < .01) but not pig weight, number of runts, number of mummies, or gestation length (P > . 10). In this study, a single injection of vitamin A at any time from weaning to farrowing did not increase litter size in sows.  相似文献   

8.
Pregnant sow nutrition has potential effects on the muscle fiber development of progeny in utero. A total of 199 Landrace x Large White sows from parities 0 to 6 and their offspring were used to evaluate the effects of increasing the feeding amount during midpregnancy on the muscle tissue, growth performance, and meat quality of the progeny. The experiment was divided into 2 study replicates, and in each replicate, sows were assigned to 1 of the 2 treatments: 1) sows in the control group (C sows) were fed 2.5 to 3.0 kg/d (feed: 12.1 MJ of ME/kg and 0.62% lysine) throughout gestation; and 2) sows in the high group (H sows) received an extra feed allowance of 1.5 kg/d for gilts and 2.0 kg/d for multiparous sows above the C amount from d 45 to 85 of gestation (period of secondary muscle fiber formation). Sow backfat was recorded on d 40 and 85 of gestation. Sow performance (litter size and piglet BW) at farrowing and on d 18 of lactation was measured. At weaning, pigs were divided into 5 BW groups/treatment, and progeny growth performance was measured during the nursery (n = 958) and the growing-finishing (n = 636) periods. At slaughter, carcass and meat quality traits (lean content, main cut weight, pH, Minolta color, and drip loss) were recorded from the second lightest group at weaning (BW group 4; n = 90), and samples from the longissimus thoracis muscle were taken to study muscle fiber characteristics (n = 70). The extra nutrition from d 45 to 85 of gestation did not lead to differences in litter size or piglet BW at farrowing and on d 18 of lactation. Pigs born to H mothers had fewer muscle fibers and fewer estimated primary and secondary fibers than did pigs born to C mothers (P < 0.05). However, postnatal growth performance was not consistently affected by the maternal treatment. The smaller number of muscle fibers found in the H group of pigs was associated with fewer type IIB fibers (P < 0.05) with greater cross-sectional areas (P < 0.10), which might be related to the significantly greater meat pH at 24 h postmortem and the smaller L* (lightness) values recorded in the H group of pigs. Results from the present study confirm the existence of effects of maternal nutrition on fetal development, at least in terms of muscle tissue development and meat quality, although with no beneficial effects were found for the postnatal growth performance of the progeny.  相似文献   

9.
Effects of dextrose plus lactose in sow’s feed were tested on subsequent reproductive performance and within litter birth weight variation. During the last week of gestation and lactation, sows were either fed a commercial lactation diet (Control: C), or an isocaloric diet containing 25 g/kg dextrose plus 25 g/kg lactose (Treatment: T). In the subsequent weaning‐to‐oestrus interval (WEI), all sows received the same amount of a commercial feed, but T sows were supplemented with 150 g dextrose plus 150 g lactose per day. Weight and backfat changes were recorded as well as litter characteristics during the treatment period and the subsequent parity. No significant effect of treatment was found on the subsequent reproductive performance, including the number of piglets born, although the number of live born piglets was 0.51 larger (p = 0.31) and weight of the live born piglets was 84 g higher in the T sows (p = 0.07) than in the C sows. When sows were categorized in sows with 12 or less and more than 12 total born piglets in the previous litter, treatment of sows with dextrose plus lactose resulted for the group with 12 or less piglets in a strong increase in subsequent total born piglets (13.97), whereas in the untreated sows the subsequent litter size was 11.89. In the group with more than 12 total born piglets, no effect of treatment was found (interaction between previous litter size and treatment p = 0.03). The within litter variation in birth weight in the subsequent litter was numerically lower in the T sows. We concluded that the use of dextrose and lactose during lactation and WEI seems to enhance litter size in sows with low previous litter size and seems to have the potential to reduce the within litter variation in birth weight.  相似文献   

10.
Ninety-one primiparous and multiparous sows and their pigs were used to evaluate the effects of a novel carbohydrate- and protein-based feed ingredient (Nutri-Pal, NP) on sow and litter performance during lactation. Nutri-Pal is a feed supplement for sows that consists of a blend of milk chocolate, brewer's yeast, whey products, and glucooligosaccharides. The dietary treatments consisted of a corn-soybean meal control and a corn-soybean meal plus 5% NP fed from d 110 of gestation to weaning. The diets were formulated to be equal in total Lys and ME. Sows were allotted to treatment based on parity, body weight, and the date of d 110 of gestation. There were 46 and 45 sows per treatment over four farrowing groups. Litters were standardized to 10 pigs and weighed within 1 d of farrowing, and all sows weaned at least 8 pigs at an average age of 21 d. Sows were weighed on d 110 of gestation, d 1 postfarrowing, and at weaning. Sows were fed three times daily during lactation. Sows were checked twice daily after weaning for signs of estrus. The weaning weight of sows fed NP was increased (P < 0.10) compared with those fed the control diet. Sows fed the control diet tended (P = 0.11) to lose more weight per day from d 110 of gestation to weaning than the sows fed NP. Otherwise, sow response variables (sow weight on d 110 of gestation and d 1 postfarrowing, d 110 of gestation to d 1 postfarrowing and lactation weight change per day, d 110 of gestation to d 1 postfarrowing, lactation, and total feed intake, days to estrus, pigs born alive or dead, and litter and average pig birth weight) were not affected (P > 0.10) by diet. There were no effects (P > 0.10) of diet on litter performance response variables (pigs weaned, litter and average pig weaning weight and gain, and survival percent). The NP feed ingredient had minor effects on sow productivity, but it did not affect litter productivity indices.  相似文献   

11.
In a Slowakian indoor pig production unit (2423 sows), from June to December 2002 all culled sows with excessive vulval discharge at culling, and with vulval discharge and periparturient disease in their previous history were subjected to retrospective lifetime production analysis. The sows were assigned to nine groups according to parity (parity 1-9). Average total litter size, average live-born litter size, average stillbirth rate, average mummy rate, and average litter weaning weight were evaluated retrospectively for all births. Non-culled sows represented the control animals. The percentage of animals with periparturient disease and vulval discharge in their history differed between parities. Parity 2, 3, and 4 sows had a significantly lower percentage of vulval discharge and periparturient disease in their history than sows of other parities. Compared to parity 1-6 sows, parity 7-9 sows had significantly lower (P < .001) conception rates, farrowing rates, and adjusted farrowing rates. Compared to parity 1-2 and 7-9 sows, parity 3-6 sows had a significantly larger (P < .001) lifetime average total born and live-born litter size. Compared to parity 1-3 and 7-9 sows, parity 4-6 sows had a significantly lower (P < .001) rate of stillbirths over all parities. No differences in mummy rates were detected between the sows of different parities. Compared to parity 1-2 and 7-9 sows, parity 3-6 sows had significantly higher (P < .001) weaning litter weights over all parities. Sows without a history of vulval discharge and periparturient disease had higher (P < .001) production levels in parity 7-9. IMPLICATIONS: The present results indicate that parity markedly influences the production level of sows that have a history of periparturient disease and vulval discharge.  相似文献   

12.
Oestrogen receptor genotypes and litter size in Hungarian Large White pigs   总被引:5,自引:0,他引:5  
A total of 869 litter records of 226 Hungarian Large White sows have been analysed to investigate the possible use of the oestrogen receptor gene (ESR) as marker to improve litter size. First, second and later parities have been evaluated separately. Frequencies of A = 0.55 and B =0.45 have been calculated for the two ESR alleles and the observed/expected number of the three genotypes were as follows: AA: 71/69.1, AB: 108/111.8 and BB: 47/45.1. BB type first and later parity sows were superior to AB and AA sows for number born alive (NBA), total number of born (TNB) and the corrected number of weaned piglets (CNW), respectively.  相似文献   

13.
主要通过比较丹系和加系纯种、二元和三元母猪的窝产健仔数,分析不同遗传背景及胎次的母猪产仔性能差异,为评估三元母猪产仔性能及其替代更新提供参考依据。研究整理了国内某规模化企业2019年5月至2020年8月间猪场的209 963条产仔记录,其中丹系56 016窝,加系153 947窝,通过单因素方差分析及邓肯检验对2个品系的母猪产健仔数进行统计分析。结果表明,丹系种猪平均窝产健仔数〔(12.54±2.61)头,n=56 016〕极显著高于加系种猪〔(11.21±2.89)头,n=153 947〕(P<0.01)。进一步分析品系内二元母猪与三元母猪的产仔性能差异,发现丹系二元母猪平均窝产健仔数〔(12.59±2.69)头,n=43 007〕显著高于丹系三元母猪〔(11.12±2.95)头,n=1 236〕(P<0.05);加系二元母猪平均窝产健仔数〔(11.55±2.81)头,n=84 374〕显著高于加系三元母猪〔(10.73±2.87)头,n=47 185〕(P<0.05)。研究还对比了胎次对产仔性能的影响,丹系二元母猪第2胎产健仔数〔(13.28±2.32)头,n=9 396〕显著高于其他胎次,加系二元母猪第3胎产健仔数〔(12.11±2.61)头,n=12 208〕显著高于其他胎次。结果说明,三元母猪的产仔性能与二元母猪相比存在明显劣势,大规模使用三元母猪可能对企业的PSY和MSY有较大影响。当有足够二元后备母猪补充群体时,应该将使用过4~5胎的三元母猪主动淘汰,将其对企业的种猪成本及收益不利影响控制在最小范围,降低对企业经济效益的影响。  相似文献   

14.
A cooperative research study involving 353 litters was conducted at three stations to determine the effects of graded levels of supplemental Cr from chromium tripicolinate (CrPic) on reproductive performance of sows and preweaning performance of their pigs. Primiparous and multiparous sows were fed fortified corn-soybean meal diets with supplemental levels of 0, 200, 600, or 1,000 ppb Cr (as-fed basis). Each station used at least three of the supplemental Cr levels, with two of those levels being 0 and 200 ppb. Station effects were observed for sow gestation weight gain, lactation weight change, lactation feed intake, litter size at birth and weaning, and pig weight at birth and weaning (P = 0.001 to 0.087). Supplemental Cr increased the number of pigs born live per litter (9.49, 9.82, 10.94, and 10.07; quadratic, P = 0.05) and sow lactation weight change (-0.2, 0.8, -4.1, and -3.9 kg; linear, P = 0.01) but decreased individual birth weight of total pigs born (1.61, 1.57, 1.47, and 1.56 kg; quadratic, P = 0.10). Tissues were obtained from a subset of sows from one station after they had completed three parities on the study. The content of Cr in the adrenal gland (16.4, 20.0, 34.0, and 48.4 ppb), kidney (35.8, 56.4, 132.6, and 176.0 ppb), and liver (22.8, 37.4, 87.6, and 92.2 ppb) was increased linearly (P = 0.001 to 0.005) by increasing CrPic supplementation. The results suggest that the supplementation level that maximizes the biological response is above that currently allowed. Additionally, supplementation of Cr at 1,000 ppb (five times currently permitted supplementation levels) was not detrimental to sow performance, even when fed continuously for three parities. There may be merit to continued research to evaluate higher supplementation rates.  相似文献   

15.
为了研究大白母猪哺乳期背膘损失对其繁殖性能的影响,试验选取大白母猪1 178头,统计6个胎次的总产仔数、产活仔数、健仔数、断奶窝重、断奶发情间隔、哺乳期背膘损失等性状,根据哺乳期的背膘损失情况将母猪分为6组:<0、0~1、1~2、3~4、5~6、>6 mm,以断奶窝重为协变量,利用最小二乘检验开展组间总产仔数、产活仔数、健仔数、断奶发情间隔等性状的差异显著性分析。结果显示,大白母猪6个胎次平均总产仔数、产活仔数、健仔数、断奶窝重、断奶发情间隔和哺乳期背膘损失分别为13.67头、11.51头、10.32头、65.90 kg、4.83 d和2.89 mm,大白母猪1~6胎产仔数在各组间存在显著差异(P<0.05)。综合全部6个胎次的结果可知,第4、5、6组间差异不显著(P>0.05),但均显著高于第1、2、3组(P<0.05);第4组总产仔数最高,达13.54头,比第1、2、3组分别高出1.90、2.29和1.63头(P<0.05)。虽然各胎次中各组间产活仔数和健仔数性状有时也出现显著差异,但综合分析6个胎次组间并未出现显著差异(P>0.05)。从断奶发情间隔性状来看,各组间均未出现显著差异(P>0.05)。结果表明,在大白猪生产中,将哺乳期母猪的背膘损失控制在3~4 mm可以获得更高的总产仔数。  相似文献   

16.
A new procedure for non-surgical deep intrauterine insemination (DUI) in unrestrained sows hormonally induced to ovulate, has been reported. In comparison with standard artificial insemination (AI), with this procedure, the sperm numbers inseminated can be reduced 20-fold without reducing the reproductive performance of these hormonally treated sows. The present study evaluated, using two experiments, the reproductive performance applying 20-fold different sperm numbers per AI dose using DUI or standard AI in spontaneously ovulating sows, under field conditions. In experiment 1, AI was applied to crossbred sows at 12, 24 and 36 h after onset of spontaneous oestrus using one of the following two regimes: (i) DUI (treatment) with 0.15 x 10(9) fresh boar spermatozoa in 5 ml of Beltsville thawing solution (BTS) extender (n = 95), and (ii) standard cervical AI (control) with 2.85 x 10(9) fresh spermatozoa in 95 ml of BTS extender (n = 95). The farrowing rates of the two groups of sows were statistically similar (NS). However, a decrease (p < 0.002) in litter size and the total number of pigs born alive was observed in sows inseminated with the DUI procedure. In experiment 2, 42 post-weaned oestrus sows were inseminated following the same design described for experiment 1 during spontaneous oestrus. On day 6 after onset of oestrus, the proximal segment of the uterine horns of the sows were flushed under surgery to retrieve eventual embryos and evaluate the success of fertilization per cornua (e.g. occurrence of effective uni- vs bilateral sperm transport rendering uni- or bilateral, complete or partial fertilization). Retrieved embryos were assessed for cleavage and number of accessory spermatozoa. Although identical overall pregnancy rates were achieved in both insemination groups, the percentage of sows with partial bilateral fertilization and unilateral fertilization was markedly higher (p < 0.05) in the DUI group (35%) compared with the control (standard AI) group (5%), with a consequent lower (p < 0.001) percentage of viable early embryos after DUI. The number of accessory spermatozoa in the zona pellucida of the embryos was highly variable, but higher (p < 0.001) in control animals than in DUI-AI. No accessory spermatozoa were found in oocytes retrieved from sows depicting unilateral fertilization. In conclusion, DUI in spontaneously ovulating sows with 0.15 x 10(9) spermatozoa renders similar farrowing rates but a lower litter size compared with use of standard AI with a 20-fold higher sperm dose. The lower litter size ought to be related to a decreased distribution of spermatozoa after DUI leading to a higher incidence of partial bilateral and unilateral fertilization.  相似文献   

17.
The effect of a modified eros centre on weaning to oestrus interval, follicle size, ovulation and farrowing rate and total born litter size was investigated. In modified eros centre 94.4% and in group housing 79.1% of the sows (p < 0.01) expressed oestrus within 10 days post‐weaning. Weaning to oestrus interval was shorter (p < 0.001) for sows kept in modified eros centre. The interval from onset of oestrus to the time of ovulation was longer for sows in group housing (p=0.05). The time of ovulation was negatively correlated (r=?0.50) with the interval from weaning to oestrus (p=0.005). The time of ovulation after onset of oestrus was significantly (p < 0.05) shorter for sows expressing oestrus within 2–4 days of weaning, compared with the animals that expressed oestrus between days 5 and 6 post‐weaning and was shortest for sows expressing oestrus after day 6 post‐weaning. Farrowing rate was not affected by a modified eros centre. Litter size tended to be smaller in group‐housed weaned sows (p=0.10). The timing of last artificial insemination relative to time of ovulation did not affect litter size (p > 0.10). The implication of these results is that a modified eros centre may improve some of the post‐weaning oestrous parameters of the sow.  相似文献   

18.
A cooperative experiment to evaluate biotin addition to sow diets was conducted at three research stations using 303 litters. Primiparous and multiparous sows (overall average parity 2.8) were fed a 14% CP corn-soybean meal diet (140 micrograms/kg biotin), with or without supplemental biotin (330 micrograms added biotin per kg feed), throughout gestation and lactation. As many sows as possible were fed their respective diets through three successive parities. During gestation, sows were given from 1.82 to 2.27 kg of feed per day, depending on environmental conditions; during lactation sows had ad libitum access to feed. Supplemental biotin had no effect (P greater than .35) on sow weights at breeding, at d 109 of gestation, at farrowing or at weaning. No differences were found in litter size at birth (P greater than .18), but at d 21 of lactation, sows fed the diet containing supplemental biotin had larger litters than sows fed the unsupplemented diet (9.4 vs 8.7 pigs, respectively; P = .01). Pig weights at birth and d 21 of lactation were not affected (P greater than .20) by dietary treatment. Biotin supplementation did not affect (P greater than .28) the length of the interval from weaning to estrus. No evidence was found that feet cracks or bruises were reduced by biotin supplementation. The results indicate that biotin supplementation of a corn-soybean meal diet during gestation and lactation increased the number of pigs at d 21 of lactation, but it did not decrease the incidence of foot lesions.  相似文献   

19.
In a field trial conducted on a commercial swine farm, lean-genotype sows (n = 485) were fed diets containing 0 or 10% supplemental fat as either medium-chain triglyceride or choice white grease from d 90 of gestation until weaning (15.5 d). Effects on standard sow and litter production traits were examined together with assessment of sow body condition using live ultrasound. Daily feed intake during lactation was 10% higher in sows consuming diets without added fat (7.2 vs 6.5 kg; P < 0.01); however, lactation ME (23.9 Mcal/d) and digestible lysine (54 g/d) intakes were unaffected (P > 0.10). Sows supplemented with fat were 4 kg heavier on d 109 of gestation (220 vs 224 kg; P < or = 0.01), 1 d after farrowing (210 vs 214 kg; P < or = 0.01), and at weaning (210 vs 214 kg; P < or = 0.01). Expressed as overall gain, this amounted to a 23% increase (0.66 vs 0.86 kg/d; P < or = 0.01) and was accompanied by a 49% increase in backfat (0.82 vs 1.68 mm; P < or = 0.03) from d 90 to farrowing. Changes in sow weight (-0.01 kg/d) and backfat (+4.2 mm) over lactation were minimal and were not affected by fat supplementation (P > or = 0.10). Longissimus muscle area at weaning was slightly greater (44.96 vs 46.2 cm2) in sows consuming fat than in control sows (P < or = 0.05), but changes in longissimus muscle area were not significant from d 90 to weaning (P > or = 0.10). Gestation length, pigs born alive, average birth weight, survival (d 3 to weaning), and days to estrus were not affected by diet (P > 0.10). However, supplemental fat increased pig ADG (192 vs 203 g/d; P < 0.01) and average pig weaning weight (4.3 vs 4.5 kg) at 15.5 d (P < or = 0.02). No differences between the two fat sources were detected. This large-scale study demonstrated that supplemental fat during gestation and lactation effectively improved sow condition and improved suckling pig performance without affecting energy intake during lactation, implying improved efficiency of sow energy utilization.  相似文献   

20.
A cooperative regional research study using 194 sows, from which data were collected from 381 litters, was conducted at 3 research stations to determine the effects of added psyllium (a concentrated fiber source) or soybean hulls to gestation diets on reproductive performance of sows and preweaning performance of their pigs. Primiparous and multiparous sows were allotted to the 3 treatments of control (corn and soybean meal-based), 0.30% psyllium, or 20% soybean hulls. Sows fed the control and 0.30% psyllium diets were provided 1.82 kg/d, and sows fed the 20% soybean hulls diet were provided 2.0 kg/d to equalize ME, Lys, Ca, P, and vitamin and trace mineral intake. Treatments 1 to 3 had 130, 130, and 121 litters per treatment from 64, 64, and 63 sows, respectively. Gestating sows fed psyllium had a greater (P < 0.01 to 0.10) d 110 gestation, farrowing, weaning, and 17 d postpartum BW and gestation ADG compared with sows fed soybean hulls. Sows fed psyllium also had a greater (P < 0.10 and 0.08) d 110 gestation BW and gestation ADG than the control sows. Sows fed soybean hulls had a reduced (P < 0.06) farrowing BW compared with the control sows. Sows fed psyllium weaned lighter (P < 0.09) pigs than sows fed the control diet. Litter size was not affected (P > 0.10) by diet. Sows fed psyllium had a reduced (P < 0.03) feed intake compared with sows fed soybean hulls for d 5 to 7 postpartum, and sows fed the control diet were intermediate. Fecal scores (1 to 5 with 1 = dry and 5 = watery) were greater (P < 0.001) and DM content was less (P < 0.001 to 0.01) in the feces of sows fed soybean hulls compared with sows fed psyllium or the control diet on d 112 of gestation and d 4 postpartum. Fecal scores were greater (P < 0.10) and fecal DM content was less (P < 0.02) in sows fed psyllium compared with sows fed the control diet only on d 4 postpartum. In summary, sows fed soybean hulls during gestation had reduced BW compared with sows fed the control diets. In contrast, sows fed psyllium had an increased BW.  相似文献   

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