Dietary micro-fibrillated cellulose improves growth, reduces diarrhea, modulates gut microbiota, and increases butyrate production in post-weaning piglets.

Dietary fiber (DF) supplementation is one of the strategies to prevent on-farm infections; it has the capability to improve gut health and piglet performance. Among the beneficial DFs, micro-fibrillated cellulose (MFC) is a new-generation plant-derived innovative feed ingredient; MFC, originating from sugar-beet pulp, has a hyper-branched structure with the ability to form shear-thinning hydrogel and has a high water-binding capacity. We aimed to determine the effects of MFC supplementation on piglets' performance before and after weaning. We included 45 sows and their piglets in this trial and monitored the results until the piglets were 7 weeks old. Piglets supplemented with MFC had higher body weight and average daily growth (ADG) than did control piglets, both pre- and post-weaning. In addition, MFC supplementation in post-weaning piglets improved butyrate content, and reduced diarrhea incidence. These phenomena, perhaps due to the MFC supplementation at different stages until age 7 weeks. In addition, after weaning, MFC supplementation stimulated the growth of butyrate-producing bacteria such as Ruminococcus.2, Ruminococcaceae.UCG.014, Intestinibacter, Roseburia, and Oribacterium genera, as well as reduced the pathogenic bacteria, such as Campylobacter, and Escherichia. Evidently, supplementation of MFC in feed to young piglets can improve growth performance and butyric acid content and reduce post-weaning diarrhea.

Impact of Intestinal Microbiota on Growth Performance of Suckling and Weaned Piglets.

Small-scale studies investigating the relationship between pigs' intestinal microbiota and growth performance have generated inconsistent results. We hypothesized that on farms under favorable environmental conditions (e.g., promoting sow nest-building behavior, high colostrum production, low incidence of diseases and minimal use of antimicrobials), the piglet gut microbiota may develop toward a population that promotes growth and reduces pathogenic bacteria. Using 16S rRNA gene amplicon sequencing, we sampled and profiled the fecal microbiota from 170 individual piglets throughout suckling and postweaning periods (in total 670 samples) to track gut microbiota development and its potential association with growth. During the suckling period, the dominant genera were Lactobacillus and Bacteroides, the latter being gradually replaced by Clostridium sensu scricto 1 as piglets aged. The gut microbiota during the nursery stage, not the suckling period, predicted the average daily growth (ADG) of piglets. The relative abundances of SCFA-producing genera, in particular Faecalibacterium, Megasphaera, Mitsuokella, and Subdoligranulum, significantly correlated with high ADG of weaned piglets. In addition, the succession of the gut microbiota in high-ADG piglets occurred faster and stabilized sooner upon weaning, whereas the gut microbiota of low-ADG piglets continued to mature after weaning. Overall, our findings suggest that weaning is the major driver of gut microbiota variation in piglets with different levels of overall growth performance. This calls for further research to verify if promotion of specific gut microbiota, identified here at weaning transition, is beneficial for piglet growth. IMPORTANCE The relationship between pigs' intestinal microbiota and growth performance is of great importance for improving piglets' health and reducing antimicrobial use. We found that gut microbiota variation is significantly associated with growth during weaning and the early nursery period. Importantly, transitions toward a mature gut microbiota enriched with fiber-degrading bacteria mostly complete upon weaning in piglets with better growth. Postponing the weaning age may therefore favor the development of fiber degrading gut bacteria, conferring the necessary capacity to digest and harvest solid postweaning feed. The bacterial taxa associated with piglet growth identified herein hold potential to improve piglet growth and health.

Offspring of hyper prolific sows: Immunity, birthweight, and heterogeneous litters.

In Europe, in the last 3 decades, there has been a constant increase in litter size due to the use of superior maternal line genetics. Those sows giving birth to more piglets than their average number of functional teats are identified as hyperprolific sows (HPS). The large number of piglets born within a litter implies not only a challenge for their access to vital resources like colostrum and milk but has a direct effect on their average birth weight and heterogeneity. These conditions are detrimental to piglets' vitality in the first hours of life and also to their immunity development. An exceptionally large number of growing fetuses in HPS leads to intrauterine crowding and consequently to an increased number of piglets suffering from intrauterine growth retardation (IUGR), which put piglets at a high risk of mortality after birth and up to later stages of life. Increased heterogeneity of birth weight within large litters increases the competition for colostrum intake, with the smaller piglets being less competitive and vital, and therefore affecting negatively their immunity. Low birth weight, long interval to reach the udder, and long duration of farrowing, all have negative effects on piglets' immunoglobulin absorption. In HPS litters, colostrum management should be focused on low birth weight piglets, anticipating their impaired capabilities associated with ingesting adequate colostrum, by shortening the time to reach the udder and reducing competition among piglets. The vitality of neonate piglets, especially low in birth weight or affected by IUGR should be enhanced to improve their body temperature and their early life stage energy metabolism.

The effect of piglet vitality, birth order, and blood lactate on the piglet growth performances and preweaning survival.

BACKGROUND: Litter size is going up in modern pig production. Due to large litter size and increased farrowing duration, newborn piglets, during parturition, can suffer from asphyxiation. This alters their blood energy parameters and can contribute to their reduced vitality at birth, which is detrimental to their growth performance and survival. We aimed to evaluate the effects of vitality score, piglets' umbilical cord blood lactate, glucose, and butyrate, and birth order on growth performance and the preweaning mortality of piglets. RESULTS: The more vital (vitality score 2, VS2) piglets had higher umbilical cord blood glucose and butyrate, lower blood lactate, and higher colostrum intake (CI) at birth, and showed higher body weight at birth and at weaning than did less vital piglets (vitality score 1, VS1). Umbilical cord lactate negatively correlated with vitality, colostrum intake, and growth before weaning. Among the four birth-order groups (BOGs), piglets born earlier during parturition had a higher mean vitality score than those born later. BOG1 and BOG2 had significantly higher CI (p < 0.05) than BOG3 and BOG4. CONCLUSION: Changes in piglets' body weight, colostrum intake, and umbilical cord lactate are associated with piglet vitality and asphyxiation during farrowing. In addition, asphyxiation induced higher umbilical cord lactate may serve as an indicator of low vitality and low colostrum consumption. Overall, improvement in piglets' vitality and in the farrowing process can help in reducing piglet mortality.

In-Feed Supplementation of Resin Acid-Enriched Composition Modulates Gut Microbiota, Improves Growth Performance, and Reduces Post-Weaning Diarrhea and Gut Inflammation in Piglets.

The weaning process represents a delicate phase for piglets, and is often characterized by lower feed intake, lower weight gain, diarrhea, and ultimately increased mortality. We aimed to determine the effects of RAC supplementation in diets on improving piglet growth and vitality, reducing post-weaning diarrhea, and enhancing gut health. In a 2 × 2 × 2 factorial experiment, we selected forty sows and their piglets. Piglets were followed until seven weeks of age. There were no significant differences found between RAC treated and control piglets until weaning (p = 0.26). However, three weeks after weaning, RAC treated piglets had higher body weight and average daily growth (ADG) than the control piglets (p = 0.003). In addition, the piglets that received RAC after weaning, irrespective of mother or prior creep feed treatment, had lower post-weaning diarrhea (PWD) and fecal myeloperoxidase (MPO) level than control piglets. Gut microbiota analysis in post-weaning piglets revealed that RAC supplementation significantly increased Lachnospiraceae_unclassified, Blautia, Butyricicoccus, Gemmiger and Holdemanella, and decreased Bacteroidales_unclassified. Overall, RAC supplementation to piglets modulated post-weaning gut microbiota, improved growth performance after weaning, reduced post-weaning diarrhea and reduced fecal myeloperoxidase levels. We therefore consider RAC to be a potential natural feed supplement to prevent enteric infections and improve growth performance in weaning piglets.

Herd-level risk factors for chronic pleurisy in finishing pigs: a case-control study.

BACKGROUND: Chronic pleurisy is a common finding in slaughtered pigs in post-mortem meat inspection. The prevalence of pleurisy has been increasing during the last decade also in Finland. The aim of this prospective case-control study was to search for environmental, infectious and management-related herd-level risk factors for pleurisy in the slaughterhouse. Altogether 46 Finnish pig herds, including 25 control (low pleurisy prevalence in meat inspection) and 21 case (high pleurisy) herds, were enrolled in the study and visited during the tenth week of the rearing period of finishing pigs. Herd personnel were asked about basic herd information, management and environmental factors. Selected pigs were examined clinically, environmental parameters were measured and 15 blood samples per herd were taken during herd visits. Antibodies against Actinobacillus pleuropneumonia serotype 2 (APP2) and ApxIV toxin and swine influenza virus were measured. After the slaughter of study pigs, meat inspection results of the batch were gathered from slaughterhouses. Multivariate logistic regression model was built to identify possible risk factors for a herd to be a case herd (i.e. having high pleurisy values). RESULTS: Finishing herd type and herd size were observed to act as risk factors. None of clinical signs of pigs, management-related factors or environmental measurements were associated with herd status. CONCLUSIONS: As previously known, in endemic and subclinical infections such as APP, herd factors are important, but detailed risk factors seem to be difficult to identify.

The challenge of large litters on the immune system of the sow and the piglets.

The use of hyperprolific sow lines has increased litter size considerably in the last three decades. Nowadays, in some countries litters can reach up to 18-20 piglets being a major challenge for the sow's physiology during pregnancy, parturition and lactation. The increased number of piglets born per litter prolongs sensibly the duration of farrowing, decreases the piglets' average weight at birth and their vitality, increases the competition for colostrum intake and can affect negatively piglets' survival. This review aims to describe how large litters can affect the immune system of the sow and the piglets and proposes measures to improve this condition.

Behavioural alterations in piglets after surgical castration: Effects of analgesia and anaesthesia.

The present study aimed to use behavioural measures to assess pain induced by surgical castration of piglets, and evaluate the efficacy of pain-relief medications. In total, 143 male piglets from 29 sows were used. The treatments included: 1) non-castration (NC; n = 28), 2) castration without medication (SC; n = 29), 3) castration with meloxicam injection 0.4 mg/kg i.m. (ME; n = 28), 4) castration with 0.5 ml of 2% lidocaine in each testicle (LA; n = 29), and 5) castration with general inhalation anaesthesia using isoflurane (1.5%) and meloxicam injection (GA; n = 29). Behaviour was monitored continuously for a ten minute period one hour prior to castration (-1 h), as well as immediately (0 h), one hour (1 h), and two hours (2 h) after castration. Behaviour was also monitored twice (08:00 and 20:00) during the following day. Compared to -1 h, castration induced changes in several behavioural measures in SC piglets at 0 h, suggesting that castration was painful. Furthermore, inactive standing or sitting, tail wagging and aggressive behaviour differed between SC and NC piglets at 0 h. ME and LA piglets spent less time standing or sitting inactively, and LA and GA piglets showed more tail wagging than SC piglets at 0 h (P < 0.05 for all). No other behavioural measures differed among the various groups of castrated piglets. In conclusion, the results indicate that surgical castration is indeed painful. However, the efficacy of various pain-relief protocols in piglets shortly after castration was not verified.

BOARD INVITED REVIEW: Immunocontraception as a possible tool to reduce feral pig populations: recent and future perspectives.

The feral pig populations of many countries continue to increase. Scientific studies on population size are scarce, while the numbers of reported observations on presence of and damage caused by feral pigs are increasing. Feral pigs can carry and spread several diseases (including zoonotic), but African Swine Fever (ASF) is of most concern. It is a highly transmissible viral disease associated with an extremely high mortality rate. Since 2009 ASF has appeared in several European countries, with cases being identified first among local feral pigs and consequently in domestic pig production units, indicating a clear linkage with the movement of the feral pig population and the spread of the disease across national boundaries. Control of feral pig populations is currently under discussion. Because massive culling raises questions of animal welfare and ethics, fertility control could represent an important and effective means to control feral pig populations. Contraceptive vaccines have been used with some degree of success in many wild species because they are able to provide a long-term effect without any consequent health problems. However, extensive and efficacious use of vaccines to control feral pig populations is not simple. The aim of this article was to review the progress in immunocontraception use in feral pigs, providing an account of the current status and future perspectives.

Anti-Ascaris suum IgG antibodies in fattening pigs with different respiratory conditions.

During their migration through the pig's body, Ascaris suum larvae cause significant damage to the lungs. Little is known about the actual impact of this tissue damage on the occurrence and severity of respiratory problems in industrial pig fattening farms. In this study, we evaluated the link between the serological response to two different A. suum antigen preparations and respiratory or meat inspection outcomes. Two different serological tests were used that measure antibodies against either the A. suum haemoglobin molecule or complete homogenate of the 3rd stage larva that migrate through the lungs. Firstly, serum samples were analysed that were collected from 19 herds in which the cause of acute clinical respiratory symptoms was either Actinobacillus pleuropneumoniae, A. suum, or a miscellaneous cause. This was done to test whether serological results could confirm pathological findings. Secondly, serum samples from 60 herds of finishing pigs with a history of high or low frequency of pleuritis at meat inspection (MI), but without acute respiratory symptoms at the time of sampling, were also submitted for serological evaluation using both tests. Regression models were used to search for potential associations between the proportion of pigs testing seropositive with MI results, in particular pathological changes related to the lungs. The results of both ELISAs were strongly associated (P < 0.001) with pigs belonging to a herd where the respiratory problems could be attributed to A. suum by histology, indicating that both tests can be used to diagnose clinical respiratory outbreaks due to A. suum. In the herds without acute clinical respiratory symptoms, a positive association was found between the proportion of pigs testing seropositive and the percentage of livers rejected due to milk spots and with whole carcass condemnations. No association was found between Ascaris serology and lung pathology (pneumonia and pleuritis) registered at MI, however, challenging the likely involvement of Ascaris in the development of these lesions.

Developments of reproductive management and biotechnology in the pig.

This review aims to describe changes in production environment, management tools and technology to alleviate problems seen with the present hyperprolific sow model. Successful parturition in the pig includes the possibility to express adequate maternal behaviour, rapid expulsion of piglets, complete expulsion of placenta, elimination of uterine contamination and debris, neonatal activity and colostrum intake. We focus on management of large litters, including maternal behaviour, ease of parturition, colostrum production, piglet quality parameters and intermittent suckling. There are also some interesting developments in technology to assess colostrum and immune state of the piglet. These developments may be utilized to improve the success rate of reproductive management around farrowing, lactation and after weaning. We also discuss new insights in how to examine the health of the mammary gland, uterus and ovaries of hyperprolific sows. Finally, we assess the latest developments on breeding and technology of hyperprolific sows, including artificial insemination (AI), real-time ultrasound of the genital tract and embryo transfer (ET). We conclude that 1) for the sow to produce sufficient colostrum, both the behavioural and physiological needs of the sow need to be met before and after parturition. Furthermore, 2) new ultrasound and biopsy technology can be effectively applied for accurate diagnosis of inflammatory processes of the udder and uterus and timing of AI regarding ovulation to improve insemination efficiency. Finally, 3) developments in cryopreservation of germ cells and embryos appear promising but lack of valid oocyte collection techniques and nonsurgical ET techniques are a bottleneck to commercial ET. These latest developments in management of parturition and reproductive technology are necessary to cope with the increasing challenges associated with very large litter sizes.

Sow removal in commercial herds: Patterns and animal level factors in Finland.

This observational retrospective cohort study provides benchmarking information on recent sow productivity development in Finnish herds. It focuses on parity cycle specific trends in sow removal patterns, and especially on the role of litter performance (size and piglet survival) in sow removal. In addition, the generated models offer a tool for calculating sow removal risks in any period, which could be used in economic and other simulation models. The data used in the study pool information of sows starting the same parity cycle (1 through 8) over the enrollment period of July 1st, 2013 through June 30th, 2014 and followed until the end of the study period (December 31st, 2014), and their performance histories across their entire previous productive life. Out of 71,512 individual sow parity cycle observations from the first to the eighth, 15,128 ended up in removal. Average litter sizes exceeded 13 piglets born in total in all of the most recent farrowings. Yet, even larger litter sizes were favored by the implemented culling policies, as sows having medium and large early life litters had lower risks of removal compared to those with the smallest litters, particularly in younger animals. With regard to piglets born just prior to removal, the smallest litter sizes were associated with the greatest culling risk for sows of that particular parity. In addition, having more than one stillborn piglet in the first and second litter put the sow at higher risk of being removed in all but the last (sixth through eighth) of the studied parity cycles. Investigation of removal patterns revealed a negative linear relationship between parity count and the mean days from farrowing to removal. More specifically, the median (mean) times to removal varied across the parity cycles from 62 (72) in the first to 34 days in both the seventh and eighth (47 and 42, respectively). Moreover, one in every six sows was removed within the first and second parity cycle. The findings especially in the earliest cycles may be a reflection of removal decisions not made according to any clear and pre-determined policy, or of biological issues that prevent farmers from firmly adhering to their policy. Quantitative performance should be linked to overall system functionality and profitability while taking animal welfare into consideration in identifying opportunities to improve herd parity structure and future farm success.

Dietary supplementation with yeast hydrolysate in pregnancy influences colostrum yield and gut microbiota of sows and piglets after birth.

Dietary supplementation with yeast derivatives (YD) contributes to the health and physiology of sows and piglets, but few studies have focused on how it influences gut health and performance of sows and piglets. The goal was therefore to examine whether YD, based on brewer's yeast hydrolysate added to pregnancy diet, would affect colostrum composition, yield (CY) and gut microbiota of sows and piglets. Sows were allocated to either a control diet (n = 19) or a control diet supplemented with 2g YD/kg (n = 18) during the pregnancy. Piglets suckling belonging to the control sows (n = 114) and supplemented sows (n = 108) were also included in the study. Gut microbiota populations of sows at farrowing and piglets at one and four weeks of age were assessed using 16S rRNA gene sequencing. Colostrum samples were examined for nutritional composition and immunoglobulin (Ig) content. All piglets were individually weighed at birth and 24 hours later in order to calculate CY, and later at four weeks to calculate average daily gain (ADG). Protein, lactose and dry matter content of colostrum did not significantly differ between the two groups, while sows fed YD had higher levels of fat in their colostrum (P < 0.05). Immunoglobulin A, IgM and IgG levels in colostrum did not differ between the two groups (P >0.05). Colostrum yield was lower in the control than that in YD group (3701g vs. 4581 g; P <0.05). Although the YD supplementation did not change fecal bacteria diversity in sow, more beneficial and fermentative bacteria (Roseburia, Paraprevotella, Eubacterium) were found in the YD fed group (P <0.01) while, some opportunistic pathogens, including Proteobacteria, especially the genera Desulfovibrio, Escherichia/Shigella and Helicobacter, were suppressed. Piglets at one week of age from sows fed YD had more beneficial microbial populations with significant diversity and fewer opportunistic pathogens. Additionally, we established a Pearson's correlations between CY, colostrum components, piglet birth weight and fecal microbiota. Therefore, YD added to the sow diet during pregnancy increases colostrum availability and its energy content for neonate piglets, also promoting beneficial maternal microbial sources for neonate.

Effect of oral KETOPROFEN treatment in acute respiratory disease outbreaks in finishing pigs.

BACKGROUND: Infection with respiratory pathogens can influence production as well as animal welfare. There is an economical and ethical need to treat pigs that suffer from respiratory diseases. Our aim was the evaluation of the possible effects of oral NSAID medication given in feed in acute outbreaks of respiratory disease in finishing pigs. The short- and long-term impact of NSAID dosing on clinical signs, daily weight gain, blood parameters and behaviour of growing pigs in herds with acute respiratory infections were evaluated. Four finishing pig farms suffering from acute outbreaks of respiratory disease were visited thrice after outbreak onset (DAY 0, DAY 3 and DAY 30). Pigs with the most severe clinical signs (N = 160) were selected as representative pigs for the herd condition. These pigs were blood sampled, weighed, evaluated clinically and their behaviour was observed. After the first visit, half of the pens (five pigs per pen in four pens totalling 20 representative pigs per herd, altogether 80 pigs in four herds) were treated with oral ketoprofen (target dose 3 mg/kg) mixed in feed for three days and the other half (80 pigs) with a placebo. In three of the herds, some pigs were treated also with antimicrobials, and in one herd the only pharmaceutical treatment was ketoprofen or placebo. RESULTS: Compared to the placebo treatment, dosing of ketoprofen reduced sickness behaviour and lowered the rectal temperature of the pigs. Clinical signs, feed intake or blood parameters were not different between the treatment groups. Ketoprofen treatment was associated with somewhat reduced weight gain over the 30-day follow-up period. Concentration analysis of the S- and R-enantiomers of ketoprofen in serum samples collected on DAY 3 indicated successful oral drug administration. CONCLUSIONS: Ketoprofen mainly influenced the behaviour of the pigs, while it had no effect on recovery from respiratory clinical signs. However, the medication may have been started after the most severe clinical phase of the respiratory disease was over, and this delay might complicate the evaluation of treatment effects. Possible negative impact of ketoprofen on production parameters requires further evaluation.

Etiology of acute respiratory disease in fattening pigs in Finland.

BACKGROUND: The objective of our study was to clinically and etiologically investigate acute outbreaks of respiratory disease in Finland. Our study also aimed to evaluate the clinical use of various methods in diagnosing respiratory infections under field conditions and to describe the antimicrobial resistance profile of the main bacterial pathogen(s) found during the study. METHODS: A total of 20 case herds having finishing pigs showing acute respiratory symptoms and eight control herds showing no clinical signs suggesting of respiratory problems were enrolled in the study. Researchers visited each herd twice, examining and bleeding 20 pigs per herd. In addition, nasal swab samples were taken from 20 pigs and three pigs per case herd were necropsied during the first visit. Serology was used to detect Actinobacillus pleuropneumoniae (APP), swine influenza virus (SIV), porcine reproductive and respiratory syndrome virus (PRRSV), porcine respiratory coronavirus (PRCV) and Mycoplasma hyopneumoniae antibodies. Polymerase chain reaction (PCR) was used to investigate the presence of porcine circovirus type 2 (PCV2) in serum and SIV in the nasal and lung samples. Pathology and bacteriology, including antimicrobial resistance determination, were performed on lung samples obtained from the field necropsies. RESULTS: According to the pathology and bacteriology of the lung samples, APP and Ascaris suum were the main causes of respiratory outbreaks in 14 and three herds respectively, while the clinical signs in three other herds had a miscellaneous etiology. SIV, APP and PCV2 caused concurrent infections in certain herds but they were detected serologically or with PCR also in control herds, suggesting possible subclinical infections. APP was isolated from 16 (80%) case herds. Marked resistance was observed against tetracycline for APP, some resistance was detected against trimethoprim/sulfamethoxazole, ampicillin and penicillin, and no resistance against florfenicol, enrofloxacin, tulathromycin or tiamulin was found. Serology, even from paired serum samples, gave inconclusive results for acute APP infection diagnosis. CONCLUSIONS: APP was the most common cause for acute respiratory outbreaks in our study. SIV, A. suum, PCV2 and certain opportunistic bacteria were also detected during the outbreaks; however, viral pathogens appeared less important than bacteria. Necropsies supplemented with microbiology were the most efficient diagnostic methods in characterizing the studied outbreaks.

Effect of fenbendazole in water on pigs infected with Ascaris suum in finishing pigs under field conditions.

The husbandry of pigs for meat production is a constantly developing industry. Most studies on the effects of Ascaris suum infection in pigs and its prevention with anthelmintics are over a decade old. We examined the effect of 2.5mg fenbendazole per kg bodyweight administered in drinking water for two consecutive days on A. suum infection 1 and 6 weeks after pigs arrived to fattening units. We hypothesised that the treatment would reduce the presence of A. suum-infections, improve the average daily weight gain of pigs, reduce the percentage of liver rejections in pens by 50% and increase the lean meat percentage at slaughter by 1%. The study included a placebo group (427 pigs) and a treatment group (420 pigs) spanning four different farms previously reporting ≥15% liver rejection. The treatment was given for 2 consecutive days 1 and 6 weeks after the pigs arrived to the fattening unit. Faecal samples were collected during weeks 1, 6 and 12 from all pigs and examined for A. suum eggs. Blood was collected during weeks 1 and 12 from a subgroup of the pigs and examined for anti-A. suum antibodies and clinical blood parameters. Data on liver rejection and lean meat percentage were collected post-mortem. The proportion of Ascaris seropositive pigs changed from 8.6% to 22.2% and 20.3% to 16.3% in the placebo and treatment group respectively. Fenbendazole reduced the presence of A. suum eggs in faeces the percentage of liver rejections by 69.8%. The treatment did not affect daily weight gain or lean meat percentage. Pigs with A. suum eggs in faeces at week 6 had a lower average daily weight gain of 61.8g/day compared with pigs without parasite eggs. Fenbendazole treatment may be a useful option for farms struggling with persistent A. suum problems and demonstrate a beneficial effect on the weight gain of the animals shedding eggs in faeces and result in fewer condemned livers at slaughter.

The effects of amoxicillin treatment of newborn piglets on the prevalence of hernias and abscesses, growth and ampicillin resistance of intestinal coliform bacteria in weaned pigs.

This study investigated the effects of a single amoxicillin treatment of newborn piglets on the prevalence of hernias and abscesses until the age of nine weeks. We also studied whether the treatment was associated with growth and mortality, the need for treatment of other diseases, the proportions of ampicillin resistant coliforms and antimicrobial resistance patterns of intestinal Escherichia coli (E. coli). A total of 7156 piglets, from approximately 480 litters, were divided into two treatment groups: ANT (N = 3661) and CON (N = 3495), where piglets were treated with or without a single intramuscular injection of 75 mg amoxicillin one day after birth, respectively. The umbilical and inguinal areas of weaned pigs were palpated at four and nine weeks of age. At the same time, altogether 124 pigs with hernias or abscesses and 820 non-defective pigs from three pens per batch were weighed individually. Mortality and the need to treat piglets for other diseases were recorded. Piglet faecal samples were collected from three areas of the floors of each pen at four weeks of age. The prevalence of umbilical hernias or abscesses did not differ between the groups at four weeks of age, but it was higher in the CON group than in the ANT group at nine weeks of age (2.3% vs. 0.7%, P < 0.05). Numbers of inguinal hernias and abscesses did not differ between the groups at four or nine weeks of age. The ANT group, when it compared with the CON group, increased the weight gain between four and nine weeks of age (LS means ± SE; 497.5 g/d ± 5.0 vs. 475.3 g/d ± 4.9, P < 0.01), and decreased piglet mortality (19.5% ± 1.0 vs. 6.9% ± 1.0, P < 0.05) and the need to treat the piglets for leg problems (3.4% ± 0.3 vs. 1.9% ± 0.3%, P < 0.01) but not for other diseases by the age of four weeks. The proportion of ampicillin resistant intestinal coliform bacteria and the resistance patterns of the E. coli isolates were not different between the ANT and CON groups. In conclusion, our results showed that the amoxicillin treatment of new-born piglets produced statistically significant effect in some of the parameters studied. However, as these effects were only minor, we did not find grounds to recommend preventive antibiotic treatment. Further, continuous antimicrobial treatment of newborn piglets could negatively influence the development of the normal microbiota of the piglet and promote selection of antimicrobial resistance genes in herds. Therefore we suggest rejection of the use of routine administration of antimicrobial agents at birth.

Strategic use of anti-GnRH vaccine allowing selection of breeding boars without adverse effects on reproductive or production performances.

Boar stations raise only entire male pigs for selection as reproductive boars, but the majority of them will fail the selection process, ending at slaughter with a high risk of boar tainted meat. The aim of this study was to investigate whether a single dose of Improvac given to 16-week old boars had a negative effect on their subsequent sperm numbers and motility in 16 artificial insemination boars. We also aimed to generate more knowledge on incidence of boar taint at slaughter among Finnish pigs, compare production performances as average daily gain, feed conversion ratio, and carcass and meat quality (lean meat percentage, back fat, pH, color, androstenone, and skatole) of immunocastrated boars (n = 248) with those of entire boars (n = 268). Moreover, we aimed also to explore whether a fat biopsy taken at 16 weeks of age could already reveal the presence of boar taint compounds and be predictive of boar taint development at slaughter age. We found that 32% of entire boars (Figen Landrace, Figen Large White, and their crossbreed) slaughtered at an age of 25 weeks presented levels of androstenone and/or skatole above the threshold for boar taint in their meat. These boars (control) had higher androstenone and skatole levels in the back fat samples at slaughter (0.77 ± 0.55 and 0.09 ± 0.06 µg/g, respectively, mean ± standard deviation) than those in the immuno group (0.20 ± 0.25 and 0.06 ± 0.03 µg/g, respectively, P < 0.001). A single dose of anti-GnRH vaccine, given at 16 weeks of age, did not affect future sperm numbers and motility of boars selected for artificial insemination. We found no difference in the levels of testosterone, anti-GnRH antibodies titers, testicle morphology, and sperm numbers and motility between the boars vaccinated once, at 16 weeks of age, with anti-GnRH vaccine and the control boars (no vaccination). There were no differences in average daily gain, feed conversion ratio, lean meat percentage, and back fat between the immunocastrated boars and entire boars. Meat from immunocastrated boars had a higher pH and better color than meat from entire boars (P < 0.001), suggesting slightly improved meat quality.

Prolonged duration of farrowing is associated with subsequent decreased fertility in sows.

In modern swine production failure of sows to become pregnant within the expected time after weaning results in major economic loss and culling of sows. The objective of this study was to determine the effects of duration of farrowing on subsequent repeat breeding rate. The study was performed in a commercial sow-pool piggery system in Finland comprising 148 sows (Yorkshire × Landrace). A multivariate analysis was undertaken on data for parity, weaning to estrus interval, boar, number of inseminations, season, sow back-fat thickness, gestation length, duration of farrowing, number of live-born piglets, number of stillborn piglets, lactation length, and number of piglets weaned. Furthermore, two farrowing systems (crate vs. pen) were investigated. A binary logistic regression was used to analyze the effect of these factors on the repeat breeding rate (pregnant vs. not pregnant at first insemination after weaning). The total duration of previous farrowing was longer in rebred sows (357 ± 207 minutes, average ± SD) than in pregnant sows (255 ± 126 minutes; P < 0.01). The other parameters were not statistically significant to the outcome of first insemination after weaning. In conclusion, we established that sows with long duration of farrowing have higher repeat breeding rate at the first insemination after weaning and could be used as an indicator for subsequent fertility.