Factors affecting the transfer of porcine parvovirus antibodies from sow to piglets

The aim of the study was to investigate the effects of a number of environmental, behavioural and biological factors on passive immunization of piglets as assessed by transfer of porcine parvovirus (PPV) antibodies (ab) from the colostrum of PPV vaccinated mothers to the serum of the piglets. Twenty primiparous sows were housed in pens with peat, straw and branches for nest building. Half the sows were prevented from achieving feedback from a completed farrowing nest by repeated removal of the nest from 10 to 12 h after nest building had begun, whereas the other half kept their nests. Sow serum PPV-ab titres were positively related to colostrum PPV-ab titres at birth of the first piglet (BFP) (P < 0.001). Litter average piglet PPV-ab titre was positively related to both sow serum and colostrum PPV-ab titres (both P < 0.001). In addition, in the individual piglets. PPV-ab titres were reduced as time from BFP to birth and time from birth to first sucking increased and time spent sucking decreased (all P < 0.01). There were no effects of treatment, time spent in lateral recumbency by the sow, number of times the sow stood or piglet weight on day 1 on piglet serum PPV-ab titres. Preventing prolonged farrowing, while at the same time ensuring the piglets' access to the udder, is important for transfer of maternal immunity. Measurements of specific antibodies in sow serum during the periparturient period and in piglet serum at 28 days of age may provide a practical tool for evaluating transfer of maternal immunity from sow to piglets.     

Aspects of the transmission of protection against Mycoplasma hyopneumoniae from sow to offspring

The aims of this study were to describe the variation in concentration of antibodies to Mycoplasma hyopneumoniae in the serum and colostrum of sows, and to compare the amount of antibodies in colostrum with that obtained in the serum of the smallest piglets in a litter. In addition, the efficacy of the passive immunity in natural conditions was studied. The study was performed in a sow pool herd (600 sows) that was endemically infected with M. hyopneumoniae. Blood samples were collected from sows 19 days (n = 25) before and 3 days (n = 15) after farrowing, and a colostrum sample (n = 25) was collected on the day of farrowing. All samples were analysed for antibodies to M. hyopneumoniae with a monoclonal blocking enzyme-linked immunosorbent assay (ELISA). Twelve sows (48%) were high-responders with respect to antibody concentration in colostrum. The amount of blocking decreased in serum during the last weeks of pregnancy and 3 days post-farrowing it was only 53% of the level found in colostrum. At the age of 14 days, 30 of the smallest piglets were weaned. They were divided into three experimental groups, being the offspring of high-responding sows, low-responding sows, or a mix of high- and low-responding sows. The groups were transported to three separated isolation units and were followed until slaughter. At slaughter, lung lesions were not found. Nor could M. hyopneumoniae be demonstrated either by cultivation or by polymerase chain reaction. However, a significant increase in absorbance values, assessed by an indirect-ELISA, was demonstrated in groups established from low-responding sows. It was concluded that a high antibody level in colostrum appeared to protect piglets from M. hyopneumoniae.     

Abrasions and lameness in piglets born in different farrowing systems with different types of floor

Background

The quality of the floor is essential to the welfare of piglets as abrasions often are recorded in newborn piglets, and such lesions may lead to lameness. Apart from animal suffering, lameness contributes to losses in form of dead piglets, decreased growth, and increased use of antibiotics and manual labour.

Methods

In a herd with three different farrowing systems, 37 litters (390 piglets) were studied until the age of 3 weeks with respect to presence of skin wounds and abrasions. Lameness was registered until the age of 7 weeks. Eight lame piglets were sacrificed before medical treatment and subjected to necropsy including histopathological and microbiological examinations. Isolates of streptococci, staphylococci and E. coli were tested with respect to antimicrobial resistance. Mastitis was observed in ten sows.

Results

The most severe abrasions at carpus and soles were seen in the system with a new solid concrete floor with a slatted floor over the dunging area. The lowest magnitude was observed in the deep litter system with peat. Sole bruising was more common in the systems with concrete floor compared to the deep litter system with peat, and the differce in prevalence was significant at all examination days. The lesions decreased with time and about 75% of the treatments for lameness were performed during the first three weeks of life. The overall prevalence of lameness was highest in the system with new solid concrete floor with a slatted floor over the dunging area (9.4%) followed by the old solid concrete floor (7.5%). A lower (p < 0.05) prevalence was seen in the deep litters system with peat (3.3%). No significant relationship between mastitis and abrasions or lameness in the offspring was observed.

Conclusion

There were large differences in the prevalence of abrasions and lameness between the floor types. The deep litter system with peat provided a soft and good floor for piglets. The overall prevalence of lameness was only diagnosed in every fourth litter in that system compared to in every second litter in the systems with concrete floor. In contrast, the incidence of mastitis in the sows during the first week after farrowing was higher than in the systems with concrete floor.     

Effects of supplementing Saccharomyces cerevisiae fermentation product in sow diets on performance of sows and nursing piglets

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.     

提高母猪年育成仔猪数的技术措施

母猪年育成仔猪头数是衡量养猪生产水平和经济效益的重要指标,要想提高母猪年育活仔数需注意采取下列技术措施。     

Transfer of lactic acid bacterial strains from the feed to the sow, the environment, and the piglets.

The spread of lactic acid bacterial strains to the environment and to newborn piglets was investigated after feeding of such strains to sows. Rifampicin resistant bacterial strains were fed to sows, 10(10) c.f.u. per day, during the period from 1 week before expected farrowing until 1 week after farrowing. Fecal samples from the sows and samples of litter were collected for bacteriological examination together with swabs from the pens, the skin of the sows, and from the rectum of the piglets. The test strains were only excreted in relatively low amounts in the feces of the sows, approximately 10(3)-10(6) c.f.u. per gram. They were not able to displace the normal lactic acid bacterial flora in the sows nor were they transmitted to the intestinal tract of the piglets to any significant extent. After the last administration the test strains disappeared from both feces, skin, and environment, indicating that no permanent colonization had taken place, although considerable differences in duration of persistence were noticed between test strains.     

Effects of exposure to high ambient temperature and dietary protein level on sow milk production and performance of piglets.

The effects of high ambient temperature and level of dietary heat increment on sow milk production and piglet performance over a 28-d lactation were determined in 59 multiparous crossbred Large White x Landrace pigs kept at a thermoneutral (20 degrees C) or in a hot (29 degrees C) constant ambient temperature. Experimental diets fed during lactation were a control diet (NP; 17.6% CP) and two low-protein diets obtained by reduction of CP level (LP; 14.2% CP) or both reduction of CP and addition of fat (LPF; 15.2% CP); the NE:ME ratio was 74.3, 75.6, and 75.8% for NP, LP, and LPF diets, respectively. All diets provided 0.82 g of digestible lysine/MJ of NE, and ratios between essential AA and lysine were above recommendations. Creep feed was provided after d 21 of lactation. Reduction of CP level did not influence (P > 0.10) milk production, milk composition, or piglet performance. Despite higher nursing frequency (39 vs 34 sucklings per day), milk production decreased (P < 0.01) from 10.43 to 7.35 kg/d when temperature increased from 20 to 29 degrees C. At d 14, DM (18.6 vs 18.1%) and energy (4.96 vs 4.75 MJ/kg) contents in milk tended (P = 0.09) to be higher in sows kept at 29 degrees C. Over the 28-d lactation, piglet BW gain and BW at weaning decreased (P < 0.01) from 272 to 203 g/d and 9.51 to 7.52 kg, respectively, when temperature increased from 20 to 29 degrees C. Daily creep feed intake over the 4th wk of lactation was higher (P < 0.01) at 29 degrees C than at 20 degrees C (388 vs 232 g/litter, respectively), which was reflected in a greater increase in BW gain between wk 1 to 3 and wk 4 at the higher temperature (147 vs 130%); BW gain between weaning and d 14 postweaning was higher (P < 0.05) for piglets originating from sows kept at 29 degrees C (280 vs 218 g/d). In connection with their lower growth rate, DM (31.2 vs 33.0%), protein (15.5 vs 16.0%), lipid (12.3 vs 13.9%), and energy (8.39 vs 9.09 kJ/g) contents in weaned, slaughtered piglets were lower (P < 0.01) at 29 than at 20 degrees C. In conclusion, modification in the CP:NE ratio in order to decrease dietary heat increment did not affect milk production and piglet performance in thermoneutral or hot climatic conditions. Our results confirm the negative effect of high ambient temperatures on milk yield and emphasize the importance of creep feed supply to improve pre- and postweaning growth of piglets in these conditions, especially when weaning occurs after 3 wk of age.     

Consumer attitudes towards castration of piglets and alternatives to surgical castration

From three in-depth focus group studies and an internet based study concerning consumers attitudes towards surgical castration of piglets and alternatives, it can be concluded that Norwegian consumers are content with the current practice of castration using local anaesthesia. They accept castration as a necessary means to prevent the risk of boar taint in meat and thereby secure meat quality. Even though castration using anaesthesia is not a perfect solution, it is considered sufficient, and the consumers do not ask for alternatives. Most consumers were sceptical of immunocastration. The scepticism was mainly based on the fear of residuals in meat and unknown long-term consequences for the consumers. On the other hand the confidence in Norwegian control authorities is considerable, and will probably contribute to the maintenance of purchase habits even if immunocastration is to be introduced in Norwegian pig production. Castration without anaesthesia was characterized as completely unacceptable.     

Effects of irradiated sow colostrum on some biochemical and haematological measurements in newborn piglets

Some biochemical and haematological variables were measured in piglets during the first 48 hours after birth. The piglets were reared either by the sow, or bottle-fed with colostrum (either natural or sterilised by irradiation), or a commercial milk replacer. Mean haemoglobin concentrations, packed cell volumes and erythrocyte counts decreased by approximately 45 per cent in all the groups between birth and 48 hours, but leucocyte counts increased more markedly in the colostrum-fed groups. All the colostrum-fed groups showed rapid increases in serum total protein concentrations which were almost entirely due to increases in gamma globulin concentrations. There was no difference in this respect between natural colostrum and colostrum sterilised by irradiation with 500 Krad of gamma rays. Colostrum sterilised by irradiation can protect piglets against infectious agents and simplify the rearing of piglets under specific pathogen free conditions.     

Efficacy of a novel virulence gene-deleted Salmonella Typhimurium vaccine for protection against Salmonella infections in growing piglets

We have previously developed a novel attenuated Salmonella Typhimurium (S. Typhimurium) ΔcpxR Δlon vaccine. This study was carried out to examine whether this vaccine could effectively protect growing piglets against Salmonella infection. Attenuated S. Typhimurium secreting the B subunit of Escherichia coli heat-labile enterotoxin was also used as a mucosal adjuvant. Pregnant sows in groups A and B were primed and boosted with the vaccine and mucosal adjuvant, whereas sows in groups C, D and E received PBS. Piglets in groups A and C were intramuscularly primed with formalin-inactivated vaccine and orally boosted with live vaccine, while piglets in groups B, D and E received PBS. Piglets in groups A, B, C, and D were challenged with a wild type virulent S. Typhimurium at the 11th weeks of age. Colostrum sIgA and IgG titers in vaccinated groups A and B sows were approximately 50 and 40 times higher than those of non-vaccinated groups C, D and E sows (P < 0.001). Serum IgG titers of group A piglets were also significantly higher than those of groups D and E piglets during the study (P < 0.001). Furthermore, no clinical signs were observed in group A piglets during the entire experimental period after the challenge, while diarrhea was observed in many of the piglets in groups B, C, and D. No Salmonella was isolated from fecal samples of the groups A and C piglets on day 14 after challenge, whereas the challenge strain was isolated from several piglets in groups B and D. These results indicate that vaccination of the piglets with the vaccine and mucosal adjuvant in addition to vaccination of their sows induced effective protection against Salmonella infections in the growing piglets.     

Incidence of foot and skin lesions in nursing piglets and their association with behavioural activities.

A total of 356 piglets from one farm were examined for foot and skin lesions every day for the first 10 days after birth, and then on alternate days until they were weaned. Over a period of 24 days 100 per cent of the piglets examined developed sole bruising, and 49.1 per cent developed sole erosions. Sole bruising lasted for an average of 13 days and sole erosions for seven days. At the beginning of the study, a higher proportion of piglets had mild sole bruising; from three to nine days of age piglets had moderate sole bruising but from days 10 to 20 mild bruising was again observed more frequently. Skin lesions were observed on the carpal aspect of the front limbs; 60.9 per cent of the piglets developed skin abrasions, 70.7 per cent developed healed wounds and 90 per cent developed hairless patches. The skin abrasions lasted on average for six days, the healed wounds for five days and the hairless patches for eight days. Piglets which developed sole bruising and/or sole erosions on the first day of life were significantly heavier than those which did not. Continuous observations of the piglets' behaviour during the first six days of life showed that sole bruising increased as the total time spent in the creep area or lying near the sow on the solid floor increased. During the first three days of life skin abrasions increased as the total time spent lying in the creep area increased. There was a positive correlation between the total time piglets spent suckling and the incidence of carpal skin abrasions between four and six days of age. Piglets with sole bruising, sole erosions or carpal skin abrasions spent less time during the day in 'other' activities such as walking, playing or fighting.     

Campylobacter infections in calves, piglets, lambs and kids in Trinidad.

Faeces or rectal swabs from 689 diarrhoeic and non-diarrhoeic animals were cultured for thermophilic campylobacters and their antibiograms were determined. Three hundred and fifteen (45.7%) samples were positive for Campylobacter. Piglets had the highest prevalence, 79.3% (233/294) and lambs, the lowest with 17.9% (15/84) being positive. The difference was statistically significant (P < or = 0.01; chi 2). In calves, 20.5% (60/293) and in kids 38.9% (7/18) were positive for campylobacters. The prevalence of infection was not significantly (P > or = 0.05; chi 2) different between diarrhoeic (46.1%) and non-diarrhoeic (45.1%) animals nor between male (47.5%) and female (43.8%). The frequency of isolation of campylobacters harvested from semi-intensively managed animals (75.4%) was, however, significantly higher (P < or = 0.001; chi 2) than from intensively or extensively managed animals. Overall, C. coli strains (32.8%) were more frequently isolated than C. jejuni strains (12.9%) and the difference was significant (P < or = 0.001; chi 2). Biotype I accounted for 67.3% (152/226) of C. coli and 64.0% (57/89) of C. jejuni strains isolated. A total of 245 (77.8%) strains of Campylobacter exhibited resistance to one or more antibiotics and was highest to streptomycin (76.5%), kanamycin (28.6%) and neomycin (26.7%). It was concluded that Campylobacter infections were widespread in livestock in Trinidad, particularly C. coli in piglets.     

微囊丁酸钠对母猪生产性能与仔猪生长性能的影响

40头妊娠85 d健康二元杂交经产母猪(胎次、体况、前胎产仔数一致),随机分为2组,每组20个重复,每个重复1头,分别为对照组(基础日粮)、处理组(妊娠期:基础日粮+800 g/t微囊丁酸钠;哺乳期:基础日粮+500 g/t微囊丁酸钠)。结果表明,饲粮中添加微囊丁酸钠能够显著提高母猪生产后期采食量(4.56%),显著降低母猪哺乳期的体失重(P<0.05),提高仔猪断奶日增重(P<0.05)和断奶体重。此外,处理组弱仔率较对照组下降35.72%,窝断奶仔猪数和断奶仔猪均重有上升趋势(P=0.07,P=0.14)。由此可见,微囊丁酸钠可改善母猪生产性能,提高仔猪平均日增重。     

几种添加物对猪乳成分、仔猪生长及部分血液生化指标的影响

选用预产期基本一致的初产长白母猪24头,随机分为4组,每组6头。对照组饲喂基础日粮,其余3组为试验组,分别饲喂基础日粮+大豆黄酮60mg/kg、基础日粮+缬氨酸600mg/kg+大豆黄酮60mg/kg、基础日粮+烟酸铬200μg/kg+大豆黄酮60mg/kg。饲喂两个月后,各组合对初乳成分、仔猪的生产性能和断奶仔猪血液的生理生化反应的影响结果为:①母猪初乳成分的中乳蛋白和乳脂肪、乳糖含量测定结果表明,烟酸铬+大豆黄酮组、大豆黄酮组中乳蛋白含量与对照组相比差异显著(P<0.05),乳脂肪、乳糖含量差异不显著;②与对照组相比,各试验组均可以提高仔猪的初生重、21日龄(P<0.05)和断奶平均个体重(P<0.05),其中以缬氨酸+大豆黄酮组最好;③烟酸铬+大豆黄酮组在高温情况下补铬可以缓解血浆中的甘油三酯、总蛋白和球蛋白下降。而缬氨酸、烟酸铬分别与大豆黄酮共同作用对断奶仔猪血浆中尿素氮、甘油三酯、总蛋白的影响差异不显著。烟酸铬+大豆黄酮组对血浆中碱性磷酸酶的影响显著高于其它各组(P<0.05)。     

Metabolomic analysis of longissimus from underperforming piglets relative to piglets with normal preweaning growth

Background: Recent increases in intra-litter variability in weaning weight have raised swine production costs. A contributor to this variability is the normal birth weight pig that grows at a slower rate than littermates of similar birth weight. The goal of this study was to interrogate biochemical profiles manifested in skeletal muscle originating from slow growing(SG) and faster growing littermates(control), with the aim of identifying differences in metabolic pathway utilization between skeletal muscle of the SG pig relative to its littermates. Samples of longissimus muscle from littermate pairs of pigs were collected at 21 d of age for metabolomic analysis.Results: Birth weights did not differ between littermate pairs of SG and Control pigs(P 0.05). Weaning weights differed by 1.51 ± 0.19 kg(P 0.001). Random forest(RF) analysis was effective at segregating the metabolome of muscle samples by growth rate, resulting in a predictive accuracy of 81% versus random segregation(50%).Decreases in sugars in the pentose phosphate pathway(PPP) in the longissimus of SG pigs were detected(P 0.05). Decreases were also apparent in glycolytic intermediates(glycerol-3-phosphate and lactate) and key glycolysis-derived intermediates(glucose-6-phosphate and fructose-6-phosphate; P 0.05). SG pigs had increased levels of phospholipids, lysolipids, diacylglycerols, and sphingolipids(P 0.05). Pathway analysis identified a cluster of molecules associated with muscle and collagen/extracellular matrix breakdown that are increased in the SG pig(glutamate, 3-methylhistidine and hydroxylated proline moieties; P 0.05). Nicotinate metabolism was altered in SG pigs, resulting in a 78% decrease in the nicotinamide adenine dinucleotide pool(P 0.05).Conclusions: These metabolomic data provide the first evidence for biochemical mechanisms that should be investigated to determine if they have a potential role in the slow growth in some normal birth weight piglets that contribute to increased intra-litter variability in weaning weights and provides essential information and potential targets for the development of nutritional intervention strategies.     

饲喂母猪不同类型和水平的有机铁对仔猪生长和贫血状态的影响

本研究旨在评估母猪饲料中添加两种不同水平螯合态的有机铁对仔猪生长性能和改善仔猪贫血效果的研究。选取体重相近、胎次相近、遗传结构一致、健康的二元杂母猪30头,随机分为5组。对照组1组,在基础饲料中添加硫酸亚铁100 g/kg;处理组2、3、4、5分别在基础饲料中添加甘氨酸亚铁80 g/kg和100 g/kg、复合氨基酸螯合铁80 g/kg和100 g/kg。结果表明,母猪饲料中添加有机铁甘氨酸亚铁100 g/kg和复合氨基酸螯合铁80 g/kg可提高21日龄断奶仔猪体重,分别提高12.26%和10.3%;母猪饲料中添加有机微量甘氨酸亚铁和复合氨基酸螯合铁可改善母猪生产时和产后21日龄以及仔猪初生和断奶后体内血液红细胞数量(RBC)、血液平均红细胞的体积(MCV)和血液中红细胞压积(HCT),其中母猪日粮中添加甘氨酸亚铁80 g/kg和复合氨基酸螯合铁100 g/kg组仔猪血液红细胞数量(RBC)在初生和21日龄断奶分别提高6.06%和9.29%;母猪饲料中添加有机微量甘氨酸亚铁和复合氨基酸铁都可提高母猪初乳和常乳中乳铁的含量,其中添加甘氨酸亚铁100 g/kg和复合氨基酸螯合铁100 g/kg组初乳中铁浓度分别提高276%和346%。综上,通过提高母猪乳中有机铁含量可提高初生仔猪体内的铁储存与代谢以达到仔猪抵抗贫血风险的作用。     

Preventing transmission of Sarcoptes scabiei var. suis from infested sows to nursing piglets by a prefarrowing treatment with doramectin injectable solution

Studies were conducted at swine facilities in Illinois and North Carolina to evaluate the effect of treatment with doramectin injectable solution on transmission prevention of Sarcoptes scabiei var. suis from sows to nursing piglets. Approximately 42 days prefarrowing, 58 mange-free sows were experimentally infested with 200 S. scabiei in each ear. Seven to fourteen days prior to farrowing, 22 sows were given doramectin injectable intramuscularly at a dose of 300 microg/kg of body weight. A total of 21 sows served as untreated controls. Skin scrapings for mite counts and lesion scoring were performed on sows before treatment on day 21, and on either day 35 or 42. Each sow was observed on days 0, 7, 14, 21, 28, and 35 or 42 for the incidence of scratching/rubbing. Skin scrapings, lesion scoring, and observation of scratching/rubbing were performed on the piglets after weaning and at the end of the nursery stage. Geometric mean mite counts of the untreated sows were 0.70 and 0.26 on days 21 and 35 or 42, respectively, and 0.00 for doramectin-treated sows over the same time periods (P<0.05). Lesions scores and the incidence of scratching/rubbing were both higher in the untreated sows as compared to the doramectin-treated sows during the same time periods (P<0.05). Geometric mean mite counts of piglets farrowed by untreated sows were 0.50 and 0.60 after weaning and at the end of the nursery stage, respectively, and 0.00 for piglets from doramectin-treated sows over the same time periods (P>0.05). Lesion scores and the incidence of scratching/rubbing were both higher in piglets from untreated sows as compared to those piglets from doramectin-treated sows (P<0.05). Treating S. scabiei-infested sows with doramectin injectable solution before farrowing eliminated mite infestation and prevented the transmission of S. scabiei to piglets.