Comparison of sow farrowing characteristics between a Chinese breed and three French breeds

Sow farrowing characteristics, including litter size, stillbirth, kinetics of births and piglet weight traits, were compared in 4 populations: Meishan (MS), Large White (LW), Duroc × Large White (DU × LW) and Laconie (LA). The kinetics of births was characterised by farrowing duration (FD), birth interval (BI), and farrowing irregularity, estimated by the standard deviation of BI (SDBI). The within-litter distribution of piglet birth weights was described by different traits including the mean (MBW) and standard deviation (SDBW) of birth weight. Additional characteristics of the sow were also analysed: weight at farrowing (SWF), gestation length (GEST), and birth assistance (BA). The data set included 47 MS, 605 LW, 55 DU × LW and 160 LA litters. For analyses, multivariate methods were used, including principal component analyses (PCA) and multiple factorial analyses (MFA). These methods allowed the relative importance of between-breed and within-breed variability of the correlation structure to be estimated and the homogeneity between populations (by comparison of the 4 breed correlation structures) to be investigated. Though most of the variability was observed within-breed (97%), between-breed variation appeared to be highly significant (P < 0.0001). This variation was essentially due to the Meishan breed departing from others, because of the lower weight at farrowing and, to a lesser extent, to the lower number of stillbirths and lower piglet mean and standard deviation in birth weight. Litter size did not contribute much to the variability between breeds. The rather strong correlations related to between-breed structures (r > 0.70) indicated that the correlation pattern was similar among breeds. Stillbirth was independent from litter size and appeared as closely associated with farrowing duration in the French breeds.     

在母猪产房作业时要勤洗手

猪农可以从人类医学最新的研究成果中吸取教训,即应该给母猪产房提供较好的手部卫生。在参观美国的餐厅、医院或学校时,你会在这些地方的盥洗室内发现内容为请注意卫生的提示。例     

控制母猪的分娩时间

1 为何要进行诱导分娩在实施诱导分娩方案前,首先要问是不是有这样做的必要?猪场记录是否显示死胎太多(如大于10％)?初生仔猪死亡率是否太高?如果上述问题中有一个的答案为是,那么通过辅助措施加强仔猪出生的管理,将会提高仔猪的存活率.分娩期间会发生仔猪出生间隔延长(如大于45 min)的问题,有可能会导致仔猪缺氧(缺氧症).缺氧会造成仔猪死亡,或者虽不是致命的,但会会降低仔猪的存活力,从而导致新生仔猪死亡.监控母猪分娩的其它重要原因包括:仔猪初乳管理和有效的寄养措施.仔猪出生时体质较弱或且怕冷,或由于窝产仔数较多,一些仔猪就有可能得不到足够初乳,导致其被动免疫力低下.这些仔猪更容易受到病原微生物的感染,移人保育舍后,传染给其它被动免疫力较低的仔猪.     

分娩舍的规格和设计

1引言分娩舍是母猪场中最昂贵的猪舍,同时也是最重要的一个。它应该能够在开展作业时,向母猪、新生仔猪以及工作人员提供一个舒适的环境。分娩舍的设计目标是为了能够培养出尽     

不同繁殖季节对母猪产仔状况的影响

对广东省惠阳市某集约化养猪场1999-2000年度的繁殖母猪(长白×大约克)窝产仔数进行调查分析,着重讨论不同繁殖季节对母猪窝产仔数的影响。924窝不同季节配种的母猪平均窝产仔数10.04头,第四季度配种的母猪(n=265)平均窝产仔数最高,为10.38头;第二季度配种的母猪(n=181)平均窝产仔数最低,为9.68头,两者差异显著(p<0.05)。510窝不同季节分娩的母猪平均窝产仔数为10.13头,第二季度分娩的母猪(n=141)平均窝产仔数最高,为10.44头;第一季度分娩的母猪(n=109)最低,为9.72头,两者差异极显著(p<0.01)。母猪不同分娩季节对初生仔猪24 h成活率的影响明显,第四季度初生仔猪成活率最高,为95.45％;第二季度最低,为85.88％,两者差异显著(p<0.05)。结果表明,不同繁殖季节对母猪窝产仔数、初生仔猪成活率影响显著。     

Dimension and design of the farrowing unit

1引言 分娩舍是母猪场中最昂贵的猪舍,同时也是最重要的一个.它应该能够在开展作业时,向母猪、新生仔猪以及工作人员提供一个舒适的环境.分娩舍的设计目标是为了能够培养出尽可能多的仔猪和尽可能高的仔猪断奶体重.当然,技术仅仅是这一等式的一部分;环境温度和管理也发挥了重要的作用.     

小母猪的选留和育肥期的饲养管理

小母猪的选育和育肥期的饲养管理对其终生繁殖性能有着至关重要的作用，做好小母猪的前期选育和育肥期的饲养管理，可以在很大程度上提高小母猪的生产、繁殖性能及延长使用年限。１小母猪的选留 在后备母猪转入育肥群进行育肥阶段，作为养猪生产者必须做好对后备猪的选留。当仔猪达到２８或３５日龄，体重达７．５ｋｇ以上时进行第一次筛选。首先参考其父母代生产成绩，无遗传缺陷，同胞数不少于７头，有效乳头至少６对以上发育良好且对称或均匀，不少于３对在脐部之前的，无瞎奶和赘生小乳头，阴户端正，体躯匀称，肢蹄健壮，前胸和后臀丰…     

Indicators of piglet survival in an outdoor farrowing system

Pre-weaning piglet mortality continues to be a major welfare and economic concern. In outdoor farrowing systems, there is a particular need to broaden breeding goals by incorporating selection for piglet survival to improve both productivity and welfare. This study aimed to identify behavioural and physiological survival indicators that are influential in outdoor systems and that could provide additional information for use when selecting for piglet survival. Data were collected from 511 piglets from Large White × Landrace × Duroc sows and Generalised Linear Mixed Models determined which indicators were most important for piglet survival in an outdoor system. With respect to prenatal mortality (surviving vs. stillborn piglets) high ponderal index (P < 0.001) or body mass index (P < 0.001) in conjunction with being born earlier in the farrowing birth order (P < 0.001) were the most important survival indicators. Birth weight (P < 0.001) and rectal temperature 1 h after birth (P = 0.032) were the most significant postnatal survival indicators. However survival indicators identified as important in indoor, conventional farrowing crates, such as landmark behaviours (latency to reach the udder, a teat and to suckle colostrum), were not influential in this system. These results highlight the importance of studying potential indicators of survival in alternative farrowing systems to the farrowing crate.     

Effect of heterosis on performance of mice across three environments

Performance of six genetic groups of mice was studied in three different environments in order to determine the effect of heterosis on consistency of performance in varied environments. Designed as a 3 x 6 factorial, data were analyzed using least squares analyses of variance. Genetic group effects, environmental effects, genetic group x environment interaction, and heterosis were examined for 42-d weight, age and weight at vaginal opening, age and weight at puberty, ovulation rate (determined by total corpora lutea), number of implantations, and number of fetuses at 10 d of gestation. Weight at vaginal opening, ovulation rate, implantation rate and total number of fetuses exhibited significant heterosis. Regression of these traits against an environmental index (mean performance of all genetic groups over environments) provided an estimate of stability of performance. In general, genetic groups exhibiting heterosis expressed more consistent performance across environments than pure lines did. We conclude that a stability model could be used to aid in identification of lines with consistent performance for production traits in variable environments.     

Floor heating at farrowing in pens for loose-housed sows

The effects of floor heating at parturition on sow and piglet behaviour in pens were examined in a Danish production herd. A total of 50 gilts and sows were split into two groups; one (n = 25) experienced no treatment; one (n = 25) was exposed to floor heating in the area of the sow around parturition. The sows and piglets were recorded on video 24 h a day for behavioural analyses.Floor heating tended to improve piglet weight at weaning (P = 0.05) but did not affect average daily gain. Piglets in pens with floor heating were more often in proximity of the sow at posture changes than piglets from pens without floor heating on day one postpartum (P = 0.01). Floor heating did not affect duration of parturition or any of the recordings of sow behaviour significantly.     

Nitrogen requirement of pregnant gilts

Eleven Yorkshire x Landrace gravid gilts were used in two Latin square trials to determine the N requirement for pregnancy. Semipurified diets were formulated to be adequate in indispensable amino acids (IAA) and other nutrients. Diets were fed once daily (1.82 kg); L-glutamic acid, corn sugar, powdered cellulose, and soybean oil percentages differed to maintain isocaloric diets. In Trial 1, six gilts were fed diets containing 6.6 to 17.2% CP equivalent (19.2 to 50.1 g of N/d) during six 10-d periods beginning on d 40 postcoitum. In Trial 2, five gilts were fed diets containing 4.3 to 12.6% CP equivalent (12.5 to 36.8 g of N/d) during five 10-d periods beginning on d 50 postcoitum. Nitrogen balance trials were conducted during the last 5 d of each period. Blood samples were taken both before and 3 h after the last feeding of each period. Results from Trial 1 suggested that adequate N retention (10 g/d) could be attained by pregnant gilts fed less than 28 g of N/d intake when the diet contained indispensible amino acids at levels suggested by Nutrient Requirements of Swine (NRC, 1988). An intake of 20.6 g of N/d (7.1% CP equivalent) yielded near maximum N retention among pregnant gilts fed the semipurified diets in Trial 2. Other criteria measured (urine urea nitrogen and plasma urea nitrogen) had limited value in the evaluation of the N status of the pregnant gilts in these trials.     

西丰梅花鹿产仔日期重复力的估测

采用组内相关系数法,对育才种鹿场１～６产和和隆参茸场２～６产西丰梅花鹿产仔日期的重复力进行估测,分别达０．６８（Ｐ＜１．０１）和０．７１（Ｐ＜０．０１）,均属高重复力,为母鹿的产仔日期预测、合理组群和提高其繁殖指标,提供了理论依据     

Factors affecting piglet mortality in loose farrowing systems on commercial farms

Crating sows in farrowing systems greatly restricts their normal behaviour (e.g. movement, nest-building, leaving the nest site for defecation), which is usually justified by the assumption that piglet mortality is higher with loose-housed sows. Based on experiments showing that this is not the case, farrowing crates were banned in Switzerland in 1997, with a 10-year transitional period. Since then, many farms have introduced loose farrowing systems, enabling an analysis of risk factors for piglet mortality in crateless farrowing systems based on a large sample size. Data from a Swiss sow recording scheme (UFA2000) were analysed using generalised linear mixed-effects models with an underlying Poisson distribution. Average total piglet mortality for the years 2002 and 2003 on 99 farms (N = 12457 litters) with loose farrowing systems amounted to 1.36 liveborn piglets per litter. The number of crushed piglets was 0.64 piglets per litter, whereas the number of piglets that died for other reasons was 0.72 piglets per litter.Herd size, pen size, possibility of confinement of the sow, presence of piglet protection bars and year of data collection did not significantly influence total piglet losses, losses due to crushing and losses due to reasons other than crushing. With greater litter size at birth, significantly more losses occurred due to all reasons (total, crushed, others). Total piglet mortality and losses for reasons other than crushing were significantly higher in older sows. Losses were therefore mainly attributable to sow-related characteristics rather than to the design of the farrowing pen.     

Characterization of mammary gland development in pregnant gilts

The purpose of this study was to quantify mammary gland (MG) growth during pregnancy in gilts and to determine the effect of anatomical location on gland growth. Size, composition, and histomorphology of MG were determined during gestation in 29 primigravid gilts. Gilts were allotted randomly to 6 slaughter groups: d 45 (n = 6), 60 (n = 4), 75 (n = 5), 90 (n = 4), 102 (n = 5), and 112 (n = 5) of gestation. Mammary glands were obtained at slaughter, and skin and extraneous fat pad were removed to obtain parenchymal MG tissue. Mammary glands were further separated into individual MG, and their locations were recorded. Individual MG were weighed and bisected in an approximate midsagittal section to measure cross-sectional area. Mammary glands were ground individually and pooled according to anatomical region: the first and second pairs of MG = anterior MG; the third, fourth, and fifth pairs of MG = middle MG; the sixth, seventh, and eighth pairs of MG = posterior MG. Contents of DM, CP, ether extract, and crude ash were measured. Wet weight, DM, CP, and ash content of total and individual MG increased (P < 0.01) between d 45 and 112 of gestation. Cross-sectional area of individual MG increased (P < 0.01) as gestation progressed. Percentage of CP and ash increased (P < 0.01), whereas percentage of ether extract decreased (P < 0.01) as gestation progressed. This inverse relationship between percentages of CP and ether extract (r = -0.999; P < 0.0001) was consistent with the histological shift from primarily an adipose tissue in early gestation to one containing extensive lobuloalveolar tissue in late gestation. Wet weight of middle MG was greater (P < 0.05) than that of posterior MG at d 102 and 112 of gestation, and amount of CP in middle MG was greater (P < 0.05) than that in anterior and posterior MG at d 102 and 112 of gestation, indicating that middle MG grow faster than other MG during late gestation. Rates of wet weight gain and protein accretion were accelerated (P < 0.01) after d 74 and 75 of gestation, respectively, indicating the importance of MG growth during the last trimester of gestation. The increase in rate of protein accretion after d 75 indicates a greater protein requirement for MG growth during later gestation.     

Exercising stall-housed gestating gilts: effects on lameness, the musculo-skeletal system, production, and behavior

Lameness in breeding-age gilts and sows is a major cause of culling, resulting in increased economic losses and welfare concerns. This study determined if exercise during gestation would affect the musculo-skeletal system, production variables, and behavior. Gilts were blocked by BW and assigned to 1 of 3 treatment groups: control (n = 10; no exercise), low exercise (n = 14; 122 m/d for 5 d/wk), and high exercise (n = 14; 122 m/d for 2 d/wk and 427 m/d for 3 d/wk). All gilts were stall-housed during gestation, and gilts were exercised between d 35 and 110 of gestation. Lameness score, BCS, BW, and blood were taken at multiple points before gestation, and during gestation and lactation. Blood serum was analyzed for carboxy-terminal telopeptide of type I collagen. Sow lying behavior was recorded for 3 d after farrowing. Farrowing data included litter weight and size at birth and weaning, and preweaning mortality. After weaning, 38 sows were slaughtered and muscles and the bones of the left fore- and hind-limbs were harvested. Bone density and quality were determined by computed tomography (CT) scans, dual energy x-ray scans, and bone-breaking force tests. The control group took longer to lie down than both exercise groups, and the low exercise group took longer to lie down than the high exercise group (P < 0.05). The number of pigs weaned was greater in the high exercise group than the control group (P < 0.05). Piglet preweaning mortality was greatest in the control group compared with both exercise groups (P < 0.05). The low exercise treatments exhibited a greater bone density (CT) in the humerus, radius, and tibia compared with that of the control group (P < 0.05). The bone density (CT) of the humerus in the low exercise group was greater than that of the high exercise group (P = 0.03). Breaking force in the humerus and femur was greater (P < 0.05) in the low exercise group than the control group. Breaking force in the tibia of the high exercise group was greater than the control group (P = 0.01). The tibia of both the low and high exercise groups had a greater breaking force (P < 0.05) than the control group. Although there was no benefit of exercise on lameness, differences in bone density and quality, lying behavior, and piglet survivability may provide useful insight into alternative housing for sows.     

Puberty studies of Swedish crossbreeding gilts

A number of factors such as breed, feeding and management are considered to influence the attainment of puberty in gilts. The season of birth also has been indicated as a source of the variation in age at puberty (e.g. Bane et al. 1976). The chronological age is considered to be of greater importance than live weight (Anderson & Melampy 1972), but severely restricted feeding delays puberty. The recommendation in Sweden is to breed the gilts during their second or third estrus. No information is, however, available concerning the age at puberty of Swedish crossbred gilts of today. The object of the present investigation was to investigate the age at puberty of Swedish crossbred gilts by the use of careful heat checking and analyses of peripheral blood plasma levels of progesterone.