The association between sow and piglet behavior

Sows in modern pig industry are often housed individually in farrowing crates a few days before farrowing until weaning. These farrowing crates limit movements of the sow and therefore also limit them in expressing their behavior. These limitations may lead to distress with the sow and can result in stereotypical behaviors. Because it is possible that the general behavior of the mother sow also influences her piglets, the hypothesis of the present study was that there is an association between the general behavior of sows and the behavior of their piglets. Our results showed that there was indeed an association between the postures and activities of sows and the behavior of their piglets, not only for nursing–suckling behavior. Results also indicated that piglets prefer resting when sows are resting. When sows were standing up, piglets were running around more. Although there were indications that piglets were more at ease when sows were bar biting compared with when they were sham chewing, a specific relationship between sow stereotypical behavior and piglet behavior could not be demonstrated in the present study. Though, it should be taken in mind that relatively low frequencies of stereotypical behaviors were observed. Furthermore, it could be that not only the prevalence of a specific stereotypical behavior is important but also a specific threshold of that specific behavior should be exceeded to induce effects on the suckling piglets. Alternatively piglets could coinduce stereotypical behavior of the mother sow.     

Between-breed variability of stillbirth and its relationship with sow and piglet characteristics

Litter characteristics at birth were recorded in 4 genetic types of sows with differing maternal abilities. Eighty-two litters from F(1) Duroc x Large White sows, 651 litters from Large White sows, 63 litters from Meishan sows, and 173 litters from Laconie sows were considered. Statistical models included random effects of sow, litter, or both; fixed effects of sow genetic type, parity, birth assistance, and piglet sex, as well as gestation length, farrowing duration, piglet birth weight, and litter size as linear covariates. The quadratic components of the last 2 factors were also considered. For statistical analyses, GLM were first considered, assuming a binomial distribution of stillbirth. Hierarchical models were also fitted to the data to take into account correlations among piglets from the same litter. Model selection was performed based on deviance and deviance information criterion. Finally, standard and robust generalized estimating equations (GEE) procedures were applied to quantify the importance of each effect on a piglet's probability of stillbirth. The 5 most important factors involved were, in decreasing order (contribution of each effect to variance reduction): difference between piglet birth weight and the litter mean (2.36%), individual birth weight (2.25%), piglet sex (1.01%), farrowing duration (0.99%), and sow genetic type (0.94%). Probability of stillbirth was greater for lighter piglets, for male piglets, and for piglets from small or very large litters. Probability of stillbirth increased with sow parity number and with farrowing duration. Piglets born from Meishan sows had a lower risk of stillbirth (P < 0.0001) and were little affected by the sources of variation mentioned above compared with the 3 other sow genetic types. Standard and robust GEE approaches gave similar results despite some disequilibrium in the data set structure highlighted with the robust GEE approach.     

半胱胺在母猪及仔猪上的功效

选择第3和第4胎(比例4∶6)大白×长白杂交母猪30头,以评价强化保生灵TM对母猪产仔及乳猪生长性能和健康状况的功效。在怀孕后期和整个哺乳期的母猪料中添加0.05%或0.07%强化保生灵TM,母猪及仔猪的生产性能和健康状况在农场实际条件下都有改善;所有指标,如仔猪的出生窝质量、出生活仔数和断奶仔猪数、断奶窝质量和断奶仔猪体质量、断奶成活率和断奶仔猪体质量均匀度等,强化保生灵TM组都有显著改善。强化保生灵TM组的产奶量也显著提高,在哺乳期全期表现出母猪体质量损失改善及背膘损失减少,与对照组相比,母猪更健康,断奶后恢复更快。     

The relationship between the urine minute volume and mineral excretion in sow urine

A total of 2102 urine samples of 49 sows from three farms was collected. The relationship between creatinine or the urinary colour respectively and the urinary mineral concentration was investigated. A highly significant, negative correlation between the flow of urine (3.2 to 61.1 ml/min) and the creatinine concentration could be established (n = 330, r2 = 0.84). The correlation between the urinary colour and the flow of urine showed to be comparably close (r2 = 0.80). The urinary sodium, potassium, calcium, and phosphorus content was closely correlated with the creatinine concentration or the urinary colour respectively. The corrected mineral concentration (mmol/l:creatinine and/or mmol/l:urinary colour, E 405 nm) proved to be a useful parameter of the renal mineral excretion (mmol/min). It can be expected that the additional measurement of the two parameters creatinine and/or urinary colour may increase the indicative value of urine examination. In the three sow herds investigated the correlations between urinary colour and creatinine were higher than r2 = 0.85 in all cases. The relevance of the results with respect to urine examinations is discussed.     

Effects of sow-crate design on sow and piglet behavior

The effects of sow-crate design on certain behaviors of sows and piglets at farrowing and again approximately 3 wk later were evaluated with a 2 x 2 x 4 factorial arrangement of crate width (narrow [N = 55 cm] or wide [W = 64] between lowest horizontal pipes), length (short [S = 183 cm] or long [L = 198] from rump stop to front gate) and side type (lower side of sow crate "fingered" [F], "bowed" bottom bar 20 cm above the floor [B], or straight bottom bar 20 cm [S20] or 25 cm above the floor [S25]). Farrowing-crate design influenced both sow and piglet behaviors both during and immediately after parturition and during nursing-suckling bouts approximately 3 wk later. Activities of 51 sows and their piglets were videorecorded during and immediately following parturition. Sow-crate design affected neither the interval between births of successive piglets in a litter nor the frequency of standing by the sow during parturition. Latency from birth to first mammary contact (LMC) was greater with S25-sided and S sow crates, and especially with S, W crates. A significant interaction occurred between sow-crate side type and dimensions; LMC was longer when S25 sides were combined with S or W crates. Data on suckling behavior were collected from 113 litters over three successive sucklings approximately 3 wk after farrowing. Sow-crate design had no effect either on the consistency with which a piglet suckled a particular teat or teat pair or on the frequency of multiple-teat use. Piglets maintained fewer functional teats with S, S20 crates. The distribution of functional teats between rows was less symmetric with S crates. Piglets nursed with their bodies over a side bar more frequently with B- and S20-sided crates. The sow permitted her piglets to suckle while she was in a vertical stance more frequently with S and N crates, and especially with S, N crates. Sow-crate design affected important behaviors of sows and piglets both during and immediately after parturition as well as during nursing-suckling bouts about 3 wk later.     

Genetic relationship between purebred and crossbred sow longevity

Background: The overall breeding objective for a nucleus swine selection program is to improve crossbred commercial performance. Most genetic improvement programs are based on an assumed high degree of positive relationship between purebred performance in a nucleus herd and their relatives' crossbred performance in a commercial herd. The objective of this study was to examine the relationship between purebred and crossbred sow longevity performance. Sow longevity was defined as a binary trait with a success occurring if a sow remained in the herd for a certain number of parities and including the cumulative number born alive as a measure of reproductive success. Heritabilities, genetic correlations, and phenotypic correlations were estimated using THRGIBBS1F90.Results: Results indicated little to no genetic correlations between crossbred and purebred reproductive traits.This indicates that selection for longevity or lifetime performance at the nucleus level may not result in improved longevity and lifetime performance at the crossbred level. Early parity performance was highly correlated with lifetime performance indicating that an indicator trait at an early parity could be used to predict lifetime performance. This would allow a sow to have her own record for the selection trait before she has been removed from the herd.Conclusions: Results from this study aid in quantifying the relationship between purebred and crossbred performance and provide information for genetic companies to consider when developing a selection program where the objective is to improve crossbred sow performance. Utilizing crossbred records in a selection program would be the best way to improve crossbred sow productivity.     

皖南花母猪血清Tf多态性及其与繁殖性能的关系

采用垂直板聚丙烯酰胺凝胶电泳法对 115头皖南花母猪血清转铁蛋白 (Tf)多态性进行检测 ,并用二因素有互作的最小二乘模型对不同Tf基因型与母猪繁殖力的关系进行分析。结果表明 ,皖南花母猪Tf位点受 3个等位基因控制 (TfA、TfB 和TfC) ,Tf位点基因的遗传多样性指数为0 390 7,Shannon信息指数为 0 9985。不同转铁蛋白类型的皖南花母猪繁殖性能存在一定差异 ,其中TfAA个体的产仔数、产活仔数和断奶仔猪数较高 ,TfBC型个体相应指标较差 ,二者在窝产仔数上差异达到显著水平 (P <0 0 5)。但其他Tf型母猪产仔性状的最小二乘均数差异均不显著 (P >0 0 5)。同时 ,Tf型与分娩季节之间有较强的互作效应。     

母猪授乳过程中哼叫行为与仔猪的吃乳行为以及泌乳之间的关系

阐述母猪授乳过程中哼叫行为的发生及模式,同时仔猪吃乳行为进行详细的描述,探讨哼叫行为与仔猪的吃乳行为以及泌乳之间的关系.     

The relationship between thickness and snapping strength in egg shells of the domestic fowl

Comparable pieces of egg shell from individual eggs of the domestic fowl were filed to give different thicknesses, they were then snapped and the relationship between snapping strength (S) and the square of the thickness (T ²) was studied.

For shells filed on the outside and snapped outwards or filed on the inside and snapped inwards there was a very significant relationship between S and T ². For shells filed on the inside and snapped outwards, the mammillary knobs made no contribution to strength and it was only after these had been filed off that a typical relationship between S and T ² developed.

Shells filed on the outside and snapped inwards gave very variable results in relation to the removal of the first layers of shell. In some cases the removal of a thin outer layer increased the strength and in other cases it decreased it and it was only later that a steady relationship between S and T ² developed.

In general the egg shells of the domestic fowl became weaker towards the inside of the shell.     

影响母猪产仔数和仔猪初生重的因素

繁殖率是反映母猪繁殖力和猪场生产管理水平的重要经济参数。通常衡量母猪群生产性能的指标是每头母猪每年提供的断奶仔猪数,主要有两部分组成,即年母猪产仔窝数和母猪每窝的断奶仔猪数。据生产实践,有许多因素影响着母猪的生产性能,包括遗传因素、环境因素、饲养管理因素等。饲养母猪,只有年产仔窝数多,     

Effect of sow vaccination against Mycoplasma hyopneumoniae on sow and piglet colonization and seroconversion, and pig lung lesions at slaughter

The objectives of the present study were to compare Mycoplasma hyopneumoniae (Mh) colonization and serologic status on Mh vaccinated and non-vaccinated sows and to assess the effect of sow vaccination on colonization and serologic status of their piglets at weaning as well as presence of enzootic pneumonia (EP) lung lesions at slaughter. Fifty sows (25 vaccinated and 25 unvaccinated) as well as five of their piglets were included in the study. Blood samples and nasal swabs from sows at 7 weeks pre-farrowing and 1 week post-farrowing and from piglets at 3-4 weeks of age were taken. Nasal swabs and sera were tested by a nested polymerase chain reaction (nPCR) to detect Mh DNA and by an enzyme-linked immunosorbent assay (ELISA) test to detect antibodies to the pathogen, respectively. Finally, at 23 weeks of age, pigs were sent to the slaughter where the extension of EP-compatible gross lesions was assessed. Vaccination with two doses of Mh vaccine resulted in a significantly higher (p<0.05) percentage of seropositive sows than in the non-vaccinated group at 1 week post-farrowing. On the contrary, no statistical significant differences were found in the number of nasal nPCR positive sows among different treatments (p>0.05). At 3-4 weeks of age, a significantly higher percentage (p<0.001) of seropositive piglets came from vaccinated than from non-vaccinated sows. Although the number of Mh infected piglets coming from non-vaccinated sows was higher than the one from vaccinated sows, the difference was not statistically significant (p>0.05). Overall, piglets from vaccinated sows had a significant lower (p<0.05) mean of EP-compatible lung lesions (1.83+/-2.8) than piglets from non-vaccinated sows (3.02+/-3.6). Under the conditions described in this study, sow vaccination did not affect sow or piglet colonization but increased the percentage of seropositive sows and piglets at weaning and reduced significantly the mean EP-compatible lung lesion scoring at slaughter.     

新型仔猪腹泻病的病理组织学观察

对于近几年危害严重的新型仔猪腹泻病的主要脏器进行了病理组织学变化的观察,为该病的发病机理提供理论基础。采集7日龄左右的腹泻病仔猪心脏、肝脏、肾脏、脾脏、小肠进行石蜡包埋,采用H.E.染色方法观察。结果显示,病猪心脏心肌纤维间隙增宽、肌纤维断裂;肝脏淤血、坏死;肾脏充血、肾小管上皮细胞肿胀;脾脏脾小体数量减少,脾动脉周围淋巴鞘变薄;小肠绒毛上皮脱落严重。结果表明,新型仔猪腹泻病可导致机体血液循环障碍及免疫抑制。     

A field trial of the effect of improved piglet management on smallholder sow productivity in the Philippines

We conducted a randomised, controlled field trial during 1998/1999 to evaluate the hypothesis that improved piglet management would improve the reproductive performance of smallholder sows. Simple changes were introduced into the treatment herds including the construction of a heated piglet-separation pen, vitamin injections, creep feeding and early weaning. The control herds were unchanged. Data were collected from all sows in each enrolled herd over two farrowings. We enrolled 176 sows, including 170 (96 treatment and 74 control) sows that remained throughout the study period. Significant differences in the reproductive performance of treatment and control sows were recorded for interfarrowing interval (median 176 versus 220 days), average number liveborn over 2 litters (11 versus 12), and average preweaning mortality over 2 litters (0 versus 37%). Based on a discount rate of 17%, the benefit–cost ratio of the treatment was 11.1 and 12.1 over 3 and 5 years, respectively.     

Leptin in sow: Influence on the resumption of cycle activity after weaning and on the piglet gain

In sows, a strong relationship exists between body condition and reproductive efficiency and milk yield. Leptin may act as a metabolic gate which permits the activation of reproductive axis: in the sow, serum concentration of leptin was positively correlated with adiposity at farrowing. An interesting aspect useful to clarify the biology of leptin, was the discovery that the placenta expresses the ob gene, the ob receptor gene and it is a site of leptin production, suggesting a possible role of the hormone in fetal growth; after birth, the placenta functions were taken over from milk, especially to the delivery of maternal hormones and growth factors to the neonate. The exact role of maternal leptin in the physiology of neonatal piglets remains to be determined. Our aim was to evaluate if maternal leptin levels at the beginning of lactation and at weaning could predict the resumption of cycle activity and/or the piglet gain. Thirty-eight Large White × Landrace pregnant sows (16 nulliparous and 22 pluriparous) were used. Blood samples were taken from sows and piglets at d 5 and d 21 after farrowing; in the same days, milk samples were taken after oxytocin injection by means of complete manual milking of all mammary glands of one side. On the basis of the blood leptin at d 5, sows were divided into 3 groups (Low: < 2.3 ng/ml; Medium: 2.3 to 2.6 ng/ml; High: > 2.6 ng/ml). Our results show a correlation at d 5 between backfat thickness and blood leptin (r = 0.342; P < 0.05). The resumption of the cyclic activity was faster in sows with a leptin level at d 5 greater than 2.3 ng/ml (P < 0.01). Milk composition at d 5 and 21 was not affected by parity and leptin. Piglet ADG was significantly (P < 0.05) influenced by sow leptin groups (0.180 kg day^− 1 for piglets from Low group and 0.224 for High group). Piglets weaned by High group sows have shown a greater blood leptin content at weaning (P < 0.01) than other groups. In conclusion we have found a significant correlation between leptin and productive and reproductive performances of pigs. This paper underlines the pleiotropic actions exerted by leptin in the productive sow.     

The relationship between water intake and the production of "wet" droppings in the domestic fowl

Production of “wet” droppings by laying hens was associated with polydipsia. Restriction of “wet droppers” to a “normal” water intake did not lead to dehydration, loss of body weight, decline in water balance or changes in electrolyte excretion and retention. It is concluded that “wet” droppings were the direct result of a primary polydipsia rather than an obligatory loss of body water followed by an increased water intake.     

The effect of nesting material on the nest-building and maternal behavior of domestic sows and piglet production

Nest building is an important part of maternal behavior in domestic pigs. The aim of the study was to assess the effect of nesting material sawdust vs. straw on sow behavior 24 h before and after birth of the first piglet (BFP) and piglet production. Sows, housed in farrowing crates, were randomly divided into 2 treatments: sawdust (n = 12) and straw (n = 13). Sawdust and straw were provided during the pre- and parturient period; after parturition, straw was given to both experimental groups. The prepartum nesting period (the time interval between the first and last nest-building records, including all other activity and resting before BFP), the nesting records (number of nesting records), nesting duration (duration of all nesting records), the start and termination of nesting, and the frequency of prepartum postural changes were collected 24 h before BFP. After BFP, number of nesting records and time to first sucking of the litter were collected. Frequency of postural changes and duration of udder access were collected 24 h after BFP during 3 time periods (during parturition, from the end of parturition to 12 h after BFP, and 12 to 24 h after BFP) and the frequency of nursing during 2 time periods (from the end of parturition to 12 h after BFP, and 12 to 24 h after BFP). Piglet BW gain and mortality were estimated 24 h after BFP. Data were analyzed using PROC MIXED and the probability of the piglet mortality using PROC GENMOD in SAS. Nesting material did not affect (P > 0.10) most of sow prepartum nesting behavior and had no effect (P > 0.10) on the prepartum frequency of postural changes. Sows from the sawdust treatment had a longer nesting period (P < 0.05), and nest building tended to start sooner (P < 0.10) than in the straw treatment. Nesting material had only a small effect on later maternal behavior. Sows from the straw treatment tended to have more nesting records after BFP (P < 0.10). The frequency of postural changes was affected by the interaction (P < 0.01) between treatments and time period: sow from the straw treatment had more postural changes during parturition compared with other time periods and sawdust treatment. No effect (P > 0.10) of the nesting material on piglet BW gain and mortality was found. The results suggest that sawdust compared with straw as nesting material provided to sows before and through parturition does not negatively affect maternal behavior during the 24 h before and after parturition or piglet production. Therefore, sawdust can be recommended as a suitable nesting material for farrowing sows when straw is not available.