Contact with a sow in oestrus or a mature boar stimulates the onset of oestrus in weaned sows.

Post weaning anoestrus can represent a significant source of reproductive inefficiency in pig production. Although many factors such as breed, parity, season and nutrition are known to influence the interval between weaning and remating, the effect of the sow's social environment after weaning is largely unknown. For this experiment six groups of Large White/Landrace cross-bred sows weaned between August 1989 and March 1990 at a mean of 29 days after farrowing were used to investigate the effect of social environment on the onset of oestrus after weaning in the sow. Groups two, three or four sows were exposed in six replicates to the following four treatments: (1) 18 were isolated as controls, (2) 16 were housed next to an anoestrous ovariectomised sow and allowed 10 minutes physical contact with it daily, (3) 15 were housed next to an ovariectomised sow, induced into oestrus by the injection of 1 mg oestradiol benzoate, and allowed 10 minutes physical contact with it daily, and (4) 16 were housed next to a mature boar and allowed 10 minutes physical contact with it daily. Significantly more sows in treatments 3 and 4 showed oestrus within 10 days of weaning (P less than 0.05), and the onset of oestrus was more synchronised in the sows in treatment 3 than in any other treatment (P less than 0.001). The exposure of the weaned sows to an oestrous sow or a boar overcame the extension of the weaning to remating interval which occurred over the summer and in primiparous animals in other treatments.     

The use of ultrasonography for pregnancy diagnosis in the bitch

Twenty-three Greyhound bitches housed at 3 breeding kennels were examined for pregnancy via transabdominal palpation and ultrasonography. Pregnancy was timed from the calculated day of ovulation (day of ovulation = day when first pup was whelped--63), and from a single breeding date (day 0). Starting on day 10 after ovulation, 9 bitches were monitored every 3 days by ultrasonography only, to determine gestational vesicle sizes during gestation and the time when fetal movements and heartbeats could be first detected. The other 14 bitches were examined by ultrasonography and transabdominal palpation on the same day every week, starting on postovulation day 19, to compare the effectiveness of the 2 methods of pregnancy determination. Parturition was the final determinant of pregnancy status. The earliest correct diagnosis of pregnancy was at 18 days after ovulation, but fetal movements and heartbeat could not be identified until days 28 and 35, respectively. Estimation of fetal numbers by ultrasound or palpation was not reliable when there were more than four in the litter. Pregnancy and nonpregnancy were correctly determined by both methods in an increasingly greater number of bitches as gestation progressed, but ultrasonography was more accurate at all stages; on days 19 to 22, 26 to 30, 34 to 38, and greater than 40 after ovulation, correct diagnoses were made in 33%, 42%, 50%, and 75% of the bitches by palpation and in 42%, 67%, 75%, and 83% of the bitches by ultrasonography. The most common error was failure to detect pregnancy by palpation or ultrasonography in bitches with small litters and tense abdominal muscles.(ABSTRACT TRUNCATED AT 250 WORDS)     

Epidemiology and control of vaginal discharges in the sow after service

A syndrome associated with vaginal discharge, endometritis and reproductive inefficiency in the served sow is described. In some herds pregnancy failures exceeded 15 per cent with increased returns to service and sows not in pig. Predisposing factors included the age of the herd and the hygiene and management practices from weaning to service and during the 21 days after service. No one organism was implicated but venereal transmission was considered possible. One hundred and ten breeding herds were surveyed and in 26 of these control measures were necessary. These included antibacterial therapy of the prepuce of the boar and medication of the sow from weaning until 21 days after service. Such treatment together with management changes resolved the problem in 22 of the herds. The syndrome reappeared in four out of seven herds where treatment of the boar was not continued.     

Automatic detection of oestrus and health disorders using data from electronic sow feeders

This article suggests a method for detecting oestrus, lameness and other health disorders for group housed sows fed by electronic sow feeders (ESF). The detection method is based on the measure of the individual eating rank, modeled using a univariate dynamic linear model. Differences between the predicted values of the model and the observations are monitored using a control chart: a V-mask is applied on the cumulative sum of the standardized forecast errors of the model. According to the respective V-mask parameters, alarms are given for each of the three states (oestrus, lameness, others) when the deviations between model predicted values and observations exceed some defined parameters. External information is incorporated into the model to limit the number of false alarms when a subgroup of sows enters and exits a group or both. The detection method was implemented on data collected within three production herds over 12 months. Visual recordings were performed to identify sows in oestrus or with health disorders. The detection method showed a high specificity. For oestrus detection, there was a sensitivity of 59%, 70% and 75% for the three herds as compared to 9% (herd 1) and 20% (herd 2) using lists of sows as alarms. Monitoring lameness results in a sensitivity of 56%, 70% and 41%, vs. 39%, 32% and 22% using the lists; monitoring other health disorders resulted in a sensitivity of 0%, 75% and 39% for the three respective herds, vs. 34% and 16% for herds 2 and 3 using the lists. To limit the number of false alarms, it is suggested to expand the model by including daily feed intake or body activity as other response variables.     

母猪流产的病因病机与预防诊治

母猪流产是指妊娠期不足 110 d,母猪排出妊娠物,而终止妊 娠的情况.母猪流产会给繁殖猪场 带来严重的损失,降低了生产性能、 提高了养殖成本;打乱生产流程、 影响母猪群胎龄结构,甚至由此带 来生物安全风险.母猪流产不仅 仅影响着当批的配种分娩率,还 会因为处理不及时而影响其终身 繁殖性能.     

The use of feed-grade amino acids in lactating sow diets

Background: The use of feed grade amino acids can reduce the cost of lactation feed. With changing genetics,increasing feed costs, and higher number of pigs weaned with heavier wean weights further evaluation of higher inclusion levels of feed-grade amino acid in lactation diets than previously published is warranted. Two experiments(Exp.) were conducted to determine the optimal inclusion level of L-lysine HCl to be included in swine lactation diets while digestible lysine levels remain constant across dietary treatments and allowing feed grade amino acids to be added to the diet to maintain dietary ratios relative to lysine to maximize litter growth rate and sow reproductive performance. Furthermore, the studies were to evaluate minimal amino acid ratios relative to lysine that allows for optimal litter growth rate and sow reproductive performance.Results: Exp. 1: Increasing L-lysine HCl resulted in similar gilt feed intake, litter, and reproductive performance.Average litter gain from birth to weaning was 2.51, 2.49, 2.59, 2.43, and 2.65 kg/d when gilts were fed 0.00, 0.075,0.150, 0.225, and 0.30% L-lysine HCl, respectively. Exp. 2: The average litter gain from birth to weaning was 2.68,2.73, 2.67, 2.70, and 2.64 kg/d(P 0.70) when sows were fed 0.1, 0.2, 0.3, 0.4, and 0.4% L-lysine HCl plus valine,respectively. No other differences among dietary treatments were observed.Conclusions: Collectively, these studies demonstrate corn-soybean meal based lactation diets formulated with a constant SID lysine content for all parities containing up to 0.40% L-lysine HCl with only supplemental feed grade threonine and a methionine source have no detrimental effect on litter growth rate and subsequent total born.     

夏季母猪受胎率低的原因与对策

提高母猪繁殖率是实现养猪业高产、高效的最基本和最有效的途径,虽然现阶段规模化养猪场都经过了严格的选种和选育,种猪的生产性能得到了一定的提高,但每到夏季,由于高温的影响,公猪睾丸局部温度升高,生成精液里面有效精子含量较少,导致母猪受胎率还是明显不如其他季节高,呈季节性下滑。母猪的产仔数量减少,弱胎死胎增多,严重影响着规模化养猪场的经济效益,造成较大经济损失。夏季将至,如何提高母猪的受胎率已经成为各猪场最关注的问题。在生产实践中,要分清原因,采取相应对策。困难,采食量减少,母猪繁殖所需的营养物质摄入量不足,出现不规…     

Acute phase protein levels in pregnancy and oestrus cycle in bitches

The purpose of this study was to evaluate the acute phase protein (serum amyloid A, C-reactive protein, haptoglobin, ceruloplasmin and fibrinogen) profiles in pregnant dogs as well as bitches at various stages of the estrus cycle and to verify possible relationship(s) among the APPs profile and hormonal status. A total of 60 bitches of various breeds were enrolled. The animals were divided into six groups. B-mode ultrasonographic scanner (concept M/C) was used for pregnancy diagnosis, involving the first and second halves of pregnancy. Proestrus, estrus, diestrus and anestrus stages of sexual cycles were differentiated by use of vaginal cytology and blood progesterone and estradiol 17-β levels. Serum C-reactive protein (CRP), serum amyloid A (SAA), haptoglobin, ceruloplasmin and fibrinogen levels were determined. No statistically significant differences were observed between the groups with regard to the serum SAA and CRP concentrations. Haptoglobin, ceruloplasmin and fibrinogen concentrations were elevated in pregnant dogs compared to non-pregnant groups’, independently from the pregnancy stage. No statistically significant differences in acute phase protein concentrations in dogs at various stages of estrus could be detected. Results of this study indicated that ceruloplasmin and fibrinogen levels may have potential importance in the diagnosis of pregnancy, and acute phase proteins may be used for monitoring the health status of the pregnant dogs.     

患子宫内膜炎母猪阴道菌群变化与发病关系研究

探究患子宫内膜炎母猪阴道病原,采用16SrRNA测序技术对健康和患子宫内膜炎母猪阴道菌群进行比较研究。结果表明,患子宫内膜炎母猪阴道菌群的多样性和丰富度均高于健康母猪。与健康母猪阴道菌群组成相比,患子宫内膜炎母猪阴道变形菌门(Proteobacteria)的相对丰度显著增加,而厚壁菌门(Firmicutes)和梭杆菌门(Fusobacteria)显著降低(P<0.05)。在属的分类水平上,健康母猪阴道的主要优势菌属有链球菌属、梭菌属、拟杆菌属、放线杆菌等。母猪患子宫内膜炎后,大多数健康组的优势菌属丰度显著降低。特别是子宫内膜炎组中相对丰度最高的菌属Burkholderia-Paraburkholderia在健康组中未检出。试验首次发现,患子宫内膜炎母猪的阴道菌群失衡,其发病可能与Burkholderia-Paraburkholderia数量的增加有关。本研究为研究子宫内膜炎的病因及发病机制奠定基础,并为其治疗提供依据。     

初产母猪妊娠期的饲养管理要点

初产母猪妊娠期的饲养管理,对母猪的生产性能、利用年限都有影响。特别在规模化的种猪场,种母猪的年度更新率较快,初产母猪在母猪群体中所占比例较大,因此,初产母猪对养猪场的经济效益产生很大的影响。初产母猪妊娠期的饲养管理主要有以下几项注意要点。     

Behavioural signs of oestrus during pregnancy in lactating dairy cows

Abstract

Two herds of approximately 50 dairy cows were observed for oestrous behaviour for 6 weeks, 12 times a day for 30 minutes. It appeared that 3.08% of the pregnant cows showed oestrous behaviour during pregnancy (EBP) in such an intensity that they would have been considered in oestrus. With a less rigid oestrus detection threshold, 10.8% of the pregnant cows would have been considered to be in oestrus. Animals showed EBP during all months of pregnancy, but most of the behavior was observed in the middle of the gestation period.     

孕马血清和氯前列烯醇对母猪产后乏情的作用及对比试验

应用激素孕马血清PMSG和氯前列烯醇PGC对断奶后长期不发情的母猪进行治疗对比试验。结果:PGC HCG组疗效显著,母猪发情率达66.7%、配种受胎率达87.5,%平均产仔数达9.85头,均显著高于PMSG组和PGC组(p<0.01)。试验结果表明,母猪产后乏情可能主要是卵巢持久黄体病造成,应用PGC HCG治疗,可迅速溶解黄体、促使卵泡发育、成熟,得到较好的母猪发情率、受胎率和产仔数。