A case report: Actinobaculum suis infection associated with formation of pyogranuloma, epididymitis and azoospermia in a boar.

BACKGROUND: Actinobaculum suis is a bacterium known to cause infections of the urogenital tract of sows. Infection can occur through close contact to boars, who frequently carry the pathogen in their preputial diverticulum but do not become clinically diseased themselves. In the current case, Actinobaculum suis was isolated from pyogranuloma of inflamed epididymis in a boar with poor fertility. CASE PRESENTATION: Increased return to oestrus rate, which worsened after the purchase of a new boar, was reported in an organic farm in Switzerland. During herd examination, azoospermia of the boar was diagnosed, and slaughter, followed by examination of its urogenital tract, was carried out. Pathologically, pyogranuloma formation and epididymitis were diagnosed. Bacteriology of the pyogranulomas showed growth of Actinobaculum suis and mixed flora. After the boar was replaced, the return to oestrus rate improved tremendously. CONCLUSION: A close relative of Actinobaculum suis, namely Actinotignum schaalii, has already been associated with epididymitis in humans. Considering the present case and the parallels in human medicine, Actinobaculum suis should be included in the list of differentials of boars with poor fertility.

Chromosomal imbalance in pigs showing a syndromic form of cleft palate.

BACKGROUND: Palatoschisis or cleft palate is a known anomaly in pigs resulting in their death. However, little is known about its aetiology. A detailed description of the phenotype was derived from necropsy and by computed tomography revealing that all 20 cases also exhibited hypodontia and renal cysts. Furthermore, a genetic origin was assumed due to dominant inheritance as all 20 recorded cases were confirmed offspring of a single boar. RESULTS: Single nucleotide variant (SNV) genotyping data were used to map the defect in the porcine genome and led to the detection of a chromosomal imbalance in the affected offspring. Whole genome sequencing of an affected piglet and a normal full sib was used to identify a chromosomal translocation and to fine map the breakpoints in the genome. Finally, we proved that the boar, which sired the malformed piglets, carried a balanced translocation. The detected translocation of Mb-sized segments of chromosome 8 and 14 had not been previously observed during karyotyping. All affected offspring were shown to be carriers of a partial trisomy of chromosome 14 including the FGFR2 gene, which is associated with various dominant inherited craniofacial dysostosis syndromes in man, and partial monosomy of chromosome 8 containing MSX1 known to be associated with tooth agenesis and orofacial clefts in other species. CONCLUSIONS: This study illustrates the usefulness of recently established genomic resources in pigs. In this study, the application of genome-wide genotyping and sequencing methods allowed the identification of the responsible boar and the genetic cause of the observed defect. By implementing systematic surveillance, it is possible to identify genetic defects at an early stage and avoid further distribution of congenital disorders.

Sarcoptes infestation in two miniature pigs with zoonotic transmission - a case report.

BACKGROUND: Scabies is a contagious skin disease rarely described in miniature pigs. To the best of the authors' knowledge, a zoonotic transfer from infected pet pigs to humans has not been reported previously. CASE PRESENTATION: This case report describes the infestation with Sarcoptes scabiei mites in two miniature pigs presenting with unusual clinical signs, and disease transmission to a child. Two 7-month-old male castrated miniature pig siblings were examined. Both had developed skin lesions, one animal was presented for neurological signs and emaciation. They were housed together in an indoor- and outdoor enclosure. Dermatological examination revealed a dull, greasy coat with generalized hypotrichosis and multifocal erythema. Microscopic examination of skin scrapings, impression smears of affected skin and ear swabs revealed high numbers of Sarcoptes mites in both animals as well as bacterial overgrowth. A subcutaneous injection of ivermectin 0.3 mg/kg was administered to both animals and repeated after 2 weeks. Both miniature pigs received subcutaneous injections with butafosfan and cyanocobalamin, were washed with a 3% chlorhexidine shampoo and were fed on a well-balanced diet. Pig enclosures were cleaned. The infested child was examined by a physician and an antipruritic cream was prescribed. Both miniature pigs and the child went into clinical remission after treatment. CONCLUSION: Sarcoptic mange is rare or even eradicated in commercial pig farming in many countries but miniature pigs may represent a niche for Sarcoptes scabiei infections. This case report indicates that miniature pigs kept as pets can efficiently transmit zoonotic disease to humans. In addition, these animals may represent a niche for Sarcoptes scabiei infestation in countries where sarcoptic mange in commercial pig farms has been eradicated and could therefore pose, a hazard for specific pathogen free farms.

Diagnosis of diabetes insipidus observed in Swiss Duroc boars.

BACKGROUND: Diabetes insipidus (DI) is a rare disease in humans and animals, which is caused by the lack of production, malfunction or dysfunction of the distal nephron to the antidiuretic effect of the antidiuretic hormone (ADH). Diagnosis requires a thorough medical history, clinical examination and further laboratory confirmation. This case report describes the appearance of DI in five Duroc boars in Switzerland. CASE PRESENTATION: Two purebred intact Duroc boars at the age of 8 months and 1.5 years, respectively, with a history of polyuric and polydipsic symptoms had been referred to the Swine Clinic in Berne. Based on the case history, the results of clinical examination and the analysis of blood and urine, a tentative diagnosis of DI was concluded. Finally, the diagnosis was confirmed by findings from a modified water deprivation test, macroscopic examinations and histopathology. Following the diagnosis, three genes known to be involved in inherited DI in humans were analyzed in order to explore a possible genetic background of the affected boars. CONCLUSION: The etiology of DI in pigs is supposed to be the same as in humans, although this disease has never been described in pigs before. Thus, although occurring only on rare occasions, DI should be considered as a differential diagnosis in pigs with polyuria and polydipsia. It seems that a modified water deprivation test may be a helpful tool for confirming a diagnosis in pigs. Since hereditary forms of DI have been described in humans, the occurrence of DI in pigs should be considered in breeding programs although we were not able to identify a disease associated mutation.

Medicinal plants--prophylactic and therapeutic options for gastrointestinal and respiratory diseases in calves and piglets? A systematic review.

BACKGROUND: Gastrointestinal and respiratory diseases in calves and piglets lead to significant economic losses in livestock husbandry. A high morbidity has been reported for diarrhea (calves ≤ 35%; piglets ≤ 50%) and for respiratory diseases (calves ≤ 80%; piglets ≤ 40%). Despite a highly diverse etiology and pathophysiology of these diseases, treatment with antimicrobials is often the first-line therapy. Multi-antimicrobial resistance in pathogens results in international accordance to strengthen the research in novel treatment options. Medicinal plants bear a potential as alternative or additional treatment. Based on the versatile effects of their plant specific multi-component-compositions, medicinal plants can potentially act as 'multi-target drugs'. Regarding the plurality of medicinal plants, the aim of this systematic review was to identify potential medicinal plant species for prevention and treatment of gastrointestinal and respiratory diseases and for modulation of the immune system and inflammation in calves and piglets. RESULTS: Based on nine initial sources including standard textbooks and European ethnoveterinary studies, a total of 223 medicinal plant species related to the treatment of gastrointestinal and respiratory diseases was identified. A defined search strategy was established using the PRISMA statement to evaluate 30 medicinal plant species starting from 20'000 peer-reviewed articles published in the last 20 years (1994-2014). This strategy led to 418 references (257 in vitro, 84 in vivo and 77 clinical trials, thereof 48 clinical trials in veterinary medicine) to evaluate effects of medicinal plants and their efficacy in detail. The findings indicate that the most promising candidates for gastrointestinal diseases are Allium sativum L., Mentha x piperita L. and Salvia officinalis L.; for diseases of the respiratory tract Echinacea purpurea (L.) MOENCH, Thymus vulgaris L. and Althea officinalis L. were found most promising, and Echinacea purpurea (L.) MOENCH, Camellia sinensis (L.) KUNTZE, Glycyrrhiza glabra L. and Origanum vulgare L. were identified as best candidates for modulation of the immune system and inflammation. CONCLUSIONS: Several medicinal plants bear a potential for novel treatment strategies for young livestock. There is a need for further research focused on gastrointestinal and respiratory diseases in calves and piglets, and the findings of this review provide a basis on plant selection for future studies.

Impact of maternally derived immunity on piglets' immune response and protection against porcine circovirus type 2 (PCV2) after vaccination against PCV2 at different age.

BACKGROUND: This study was aimed at evaluating the clinical protection, the level of Porcine circovirus type 2 (PCV2) viremia and the immune response (antibodies and IFN-γ secreting cells (SC)) in piglets derived from PCV2 vaccinated sows and themselves vaccinated against PCV2 at different age, namely at 4, 6 and 8 weeks. The cohort study has been carried out over three subsequent production cycles (replicates). At the start/enrolment, 46 gilts were considered at first mating, bled and vaccinated. At the first, second and third farrowing, dams were bled and re-vaccinated at the subsequent mating after weaning piglets. Overall 400 piglets at each farrowing (first, second and third) were randomly allocated in three different groups (100 piglets/group) based on the timing of vaccination (4, 6 or 8 weeks of age). A fourth group was kept non-vaccinated (controls). Piglets were vaccinated intramuscularly with one dose (2 mL) of a commercial PCV2a-based subunit vaccine (Porcilis® PCV). Twenty animals per group were bled at weaning and from vaccination to slaughter every 4 weeks for the detection of PCV2 viremia, humoral and cell-mediated immune responses. Clinical signs and individual treatments (morbidity), mortality, and body weight of all piglets were recorded. RESULTS: All vaccination schemes (4, 6 and 8 weeks of age) were able to induce an antibody response and IFN-γ SC. The highest clinical and virological protection sustained by immune reactivity was observed in pigs vaccinated at 6 weeks of age. Overall, repeated PCV2 vaccination in sows at mating and the subsequent higher levels of maternally derived antibodies did not significantly interfere with the induction of both humoral and cell-mediated immunity in their piglets after vaccination. CONCLUSIONS: The combination of vaccination in sows at mating and in piglets at 6 weeks of age was more effective for controlling PCV2 natural infection, than other vaccination schemas, thus sustaining that some interference of MDA with the induction of an efficient immune response could be considered. In conclusion, optimal vaccination strategy needs to balance the levels of passive immunity, the management practices and timing of infection.

Reliability of operational data from pig herds and performance ratings by veterinarians and pig farmers collected during telephone interviews for the evaluation of a PCV2 piglet vaccination.

BACKGROUND: The aim of the present study was to evaluate the feasibility of using a telephone survey in gaining an understanding of the possible herd and management factors influencing the performance (i.e. safety and efficacy) of a vaccine against porcine circovirus type 2 (PCV2) in a large number of herds and to estimate customers' satisfaction. RESULTS: Datasets from 227 pig herds that currently applied or have applied a PCV2 vaccine were analysed. Since 1-, 2- and 3-site production systems were surveyed, the herds were allocated in one of two subsets, where only applicable variables out of 180 were analysed. Group 1 was comprised of herds with sows, suckling pigs and nursery pigs, whereas herds in Group 2 in all cases kept fattening pigs. Overall 14 variables evaluating the subjective satisfaction with one particular PCV2 vaccine were comingled to an abstract dependent variable for further models, which was characterized by a binary outcome from a cluster analysis: good/excellent satisfaction (green cluster) and moderate satisfaction (red cluster). The other 166 variables comprised information about diagnostics, vaccination, housing, management, were considered as independent variables. In Group 1, herds using the vaccine due to recognised PCV2 related health problems (wasting, mortality or porcine dermatitis and nephropathy syndrome) had a 2.4-fold increased chance (1/OR) of belonging to the green cluster. In the final model for Group 1, the diagnosis of diseases other than PCV2, the reason for vaccine administration being other than PCV2-associated diseases and using a single injection of iron had significant influence on allocating into the green cluster (P < 0.05). In Group 2, only unchanged time or delay of time of vaccination influenced the satisfaction (P < 0.05). CONCLUSION: The methodology and statistical approach used in this study were feasible to scientifically assess "satisfaction", and to determine factors influencing farmers' and vets' opinion about the safety and efficacy of a new vaccine.

[Continuous, subjective sonographic grayscale analysis of uterine involution in sows during the postpartum period]. / Kontinuierliche subjektive sonographische Graustufenanalyse der Uterusinvolution von Zuchtsauen im Puerperium.

OBJECTIVE: The aim of this study was to analyse the continuous and subjective evaluation of echogenicity, echotexture of the puerperal uterus as well as the presence of intrauterine fluid in sows of differing parity stages. The goal was to determine associations between grayscale values and simultaneously assessed uterine diameter, body condition, and additional performance parameters such as farrowing duration, placenta expulsion duration, placenta weight and litter weight. MATERIAL AND METHODS: The study population included 95 sows housed either in free farrowing (n = 46) or crated (n = 49) stables. Transabdominal ultrasound was performed daily between postpartum days 2-14 (p. p.) and the day before weaning. Echogenicity (ranging between anechoic (1)-hyperechoic (6)), echotexture (homogenous/heterogeneous), and the presence of intrauterine fluid (yes/no) was evaluated on three cross-sections of the uterine horn/sow/day. RESULTS: In the first week p.p, most sows showed a medium (median = 4.0) echogenicity, whereas from day 7 p. p., echogenicity decreased (median = 3.5 to 3.0). Echotexture between days 2-7 p.p was mainly heterogeneous, whereas between days 8-14 p.p, it proved to be mostly homogeneous. Intrauterine fluid was detected until day 9. Echogenicity exhibited significant association with farrowing duration (FD) on days 8-14 p. p. (p = 0.048). Sows with FD > 300 min showed slightly lower echogenicity (median = 3.0) than sows with FD ≤ 300 min (median = 3.5). There was a positive correlation between uterine diameter and echogenicity on day 2-7 p. p. (r = 0,359, p < 0.001) and days 8-14 p. p. (r = 0,381, p < 0.001). CONCLUSIONS: Subjective grayscale analysis by ultrasonography is suitable in characterizing uterine echogenicity and echotexture as well as intrauterine fluid in post-partum sows. The presented findings suggest that this may aide in assessing patterns of the sow's puerperium. CLINICAL RELEVANCE: The subjective grayscale analysis is suitable in clinically assessing echogenicity and echotexture during the postpartum phase. The subjective grayscale analysis provides initial indications concerning status of uterine health and involution in sows. Based on the ultrasonographic findings, treatment may be initiated and subsequently evaluated. Furthermore, the results of the subjective grey analysis in combination with further performance characteristics can be implemented to cull breeding sows. Furthermore, the results of the subjective grey analysis in combination with additional performance characteristics may be used in order to cull/reject sows exhibiting pathophysiologic findings from further breeding.

Effect of 1,25-Dihydroxyvitamin D3-Glycosides on the Farrowing Process and Piglet Vitality in a Free Farrowing System.

Vitamin D improves the reproductive efficiency in animals. This study aimed to examine the effects of 1,25-dihydroxyvitamin D3-gylcosides (1,25-vitD) on the farrowing process in sows and the vitality of their piglets. In total, 100 sows were allocated into two groups at insemination ('1,25-vitD' and 'negative control'). The 1,25-vitD group received 260−300 mg/sow/day 1,25-vitD in their feed during the gestation period. Backfat thickness, fecal score, and the farrowing process was evaluated. The piglets were categorized into live born or stillborn, and vitality was evaluated by assessing the umbilical cord and the meconium score. The number of total-born piglets in sows of '1,25-vitD' was higher and the farrowing duration was shorter than in the negative control group without showing significance in the univariable analysis. In a linear multiple regression model including the variables 'farrowing duration', 'total born piglets' and '1,25-vitD' differences became evident. We found that 1,25-vitD was associated with a reduced farrowing duration (p = 0.055). Moreover, significantly more mummies (p < 0.01) and short ruptured umbilical cords (p < 0.05) were observed in the 1,25-vitD group. This study showed an effect of 1,25-vitD on the farrowing process. However, more research is needed to better describe the mechanism of 1,25-vitD in detail.

Factors driving pig owners' motivation and satisfaction to perform eradications from Swine dysentery.

Brachyspira hyodysenteriae is one of the agents of swine dysentery (SD) and its eradication is an effective, but costly control measure. Being a voluntary measure, knowledge about drivers of motivation and satisfaction regarding the eradication of SD would help to convince farmers to eradicate. We aimed to describe eradications performed in Switzerland and to analyse factors influencing the pig owners' perception (motivation and satisfaction) of SD eradications to provide a basis to formulate recommendations and guidelines. Pig farmers (n = 68) having conducted an SD eradication and being interested in the study were interviewed using a standardised digital questionnaire. We assessed their motivation as moderately or highly motivated. Based on the farmers' evaluation of nine aspects of the eradication, satisfaction was considered to be moderate (<7/9 aspects positively evaluated) or high (≥7/9). Farms with fattening pigs and farms with breeding stock were analysed separately in subsets. First, multivariable factor analysis for mixed data (FAMD) were performed to describe the main patterns of variation. Then, risk factors for motivation and satisfaction were quantified by means of logistic regression models. Mainly total depopulations (73.5%) had been performed. Of the 36 farmers with breeding pigs, 24 were highly motivated, and 20 highly satisfied. Of the 61 farmers with fattening pigs, 45 were highly motivated and 42 highly satisfied. The FAMD revealed that the two main components explained only 17.0% and 11.0% (breeding stock) and 13.0% and 11.0% (fattening pigs) of the total variation, respectively. For farmers with breeding stock no significant factors for motivation were detected, but they were more satisfied (OR 25.0) when they had a batch farrowing of 3 weeks. Farmers with fattening pigs were more likely to be more motivated when providing access to outdoor areas (OR 3.3) and when it was their own initiative (OR 5.5). Farmers were more likely to be satisfied when they had only fattening pigs (OR 5.7), when the eradication was their own initiative (OR 5.5) and when they did not disinfect the barns during the eradication (OR 15.6). Farmers deciding themselves to eradicate are presumably more likely convinced of the benefits of the eradication. Satisfaction associated with a 3-weeks batch farrowing might be related to an easier to organise eradication and no disinfection to reduced labour and costs. In summary, the majority of the farmers were satisfied with the eradication. Education could promote self-motivation of farmers, and subsidies might support the implementation of SD eradications.

Influence of the farrowing process and different sow and piglet traits on uterine involution in a free farrowing system.

An inadequate uterine involution can lead to postpartal disorders in sows and thereby negatively affects the reproductive cycle and performance of the animals. Therefore, the aim of the study was to evaluate the influence of the farrowing process and different sow and piglet traits on the uterine involution in a free farrowing system. In total three data sets of 48 crossbred sows (Large White x Landrace) from the peripartal period were synthesised and analysed. The uterine diameter of three uterine horns per sow was measured daily during the first two weeks postpartum using ultrasonography and then the uterine regression was calculated. Furthermore, the following sow and piglet traits before and during parturition were assessed: parity, body condition score, backfat thickness, gestation length, number of live born piglets, number of stillborn piglets, farrowing duration, duration of placenta expulsion, litter weight, placenta weight, number of placenta parts, faecal score, and birth induction. In addition, the following parameters were recorded five days after farrowing: body temperature, severity and amount of vaginal discharge, pathological colour of vaginal discharge, and lack of appetite. Spearman's correlation test was used to examine the association between the parameters within the group and uterine regression. In addition, a linear multiple regression was used to model the relationship between the uterine involution and explanatory variables from the peripartal period. The mean diameter of the uterus decreased from 32.5 mm on day 2 post-partum to 11.4 mm on day 12 post-partum, which is a relative regression of 66%. In the linear multiple regression model, a significant influence of the body condition score (p = 0.046) and the presence of high body temperature (p = 0.022) on uterine involution was detected. When the BCS increases by one unit (from BCS 3 to 4), the relative regression of the uterine involution decreases by approximately 8% and when fever is present, uterine involution is almost 6% slower. Furthermore, a significant correlation between the gestation length and the uterine involution (r = 0.31; p = 0.035) was identified. However, no correlation between the farrowing process and piglets' traits on the uterine involution was detected. This study showed that the body condition score, the gestation length and fever in the first five days after farrowing had significant effects on uterine involution in sows in a free farrowing system. Therefore, these parameters should be routinely monitored in the farrowing management to assess reproductive health post-partum and warrant early intervention.

Observation of dose dependent intravaginal Prostaglandin E2 application in free farrowing sows during parturition - a pilot study.

The duration of birth is an important factor influencing the survival of piglets and the health of sows. A prolonged parturition is usually treated with oxytocin, even though several undesirable side effects are described. Therefore, the aim of this study was to evaluate the safety and efficacy of Prostaglandin E2 (PGE2) of different concentrations as an intravaginal applied gel after the birth of the fourth piglet in sows. Twelve sows were randomly allocated to one of four treatment groups: Group I (control group) application of placebo gel; Group II application of 0.5 mg; Group III application of 1.0 mg PGE2; Group IV PGE2 application of 2.0 mg PGE2. Total duration of parturition (time between first piglet and last placenta), piglet interval before and after treatment and placenta expulsion duration (time between first and last placenta) were recorded, and each piglet was scored for meconium staining and vitality. Furthermore, stillborn piglets were categorized into ante-partum and intra-partum deaths.A significant dose-dependent effect of PGE2 after the fourth piglet in a linear regression model with group I, II and III on the total duration of parturition and the placenta expulsion duration was detected. An increase of the PGE2 dosage from 0 to 1 mg significantly reduced the total duration of parturition (group I: 553.7 ± 114.2; group II:456 ± 167.9; group III: 284.7 ± 40.5; p-value: 0.02) and placenta expulsion duration (group I: 364 ± 120; group II: 289 ± 144.1; group III: 119 ± 46.13; p-value: 0.03). Although no further significant differences between the groups using ANCOVA and a linear regression model including all groups were detected, severe meconium staining in more than 10% of piglets was observed in group II and IV. Moreover, piglets of group IV showed oedematous and haemorrhagic umbilical cords, lethargy and anoxia after treatment, and intra-partum deaths were recorded.The best outcome for the sows and piglets was achieved using the 1 mg PGE2 dosage, whereas the other dosages showed more negative side effects, impairing the health and welfare of the animals. The results of this study can be used for further studies with larger sample sizes.

Effect of intramuscular and intravaginal PGE-2 treatment compared to intramuscular oxytocin treatment in eutocic sows on the farrowing performance in a free farrowing system.

A duration of parturition beyond 300 min negatively impacts the health of the sow and the survival of piglets during parturition. Hence, oxytocin is widely used to speed up the parturition. However, oxytocin's negative side effects raise the need of finding alternative treatments such as those already implemented in human medicine. The aim of this study was to evaluate the efficacy of Prostaglandin E2 (PGE2) applied intravaginally (PGE2-V) (1.0 mg) or intramuscularly (PGE2-M) (2.5 mg) to improve the parturition process after expulsion of the fourth piglet compared to a placebo (P-V), which was sterile intravaginal gel or intramuscular oxytocin application (OXY-M) (20 iu) in free farrowing systems.In total, 201 eutocic sows were examined after stratification by parity and random allocation into groups: 54 (P-V), 48 (OXY-M), 50 (PGE2-V), 49 (PGE2-M). Farrowing duration (time between first piglet and last piglet), piglet interval and placenta expulsion duration (time between first and last placenta) were recorded, and each piglet was scored for meconium staining and vitality. Furthermore, stillborn piglets were categorized into ante-partum and intra-partum deaths.Under the present conditions, neither administration of PGE2 nor oxytocin revealed a significant effect on the farrowing process or the vitality of the piglets when compared to untreated sows. Nonetheless, significant differences could be detected between PGE-2 and oxytocin treatments. The duration of farrowing was significantly shorter in oxytocin-treated sows (156 min) compared to sows treated intramuscularly with PGE2 (238 min). Furthermore, the placenta expulsion duration in the OXY-M group (130 min) significantly differed from PGE2-V (198 min) and PGE2-M group (218 min). Although these accelerations of parturition might be considered as a beneficial effect, routine treatment with uterotonic agents after birth of the fourth piglet in free farrowing eutocic sows cannot be recommended, because an overall benefit when compared to untreated sows was not approved.

Correlation of Lawsonia intracellularis positivity in quantitative PCR and herd factors in European pig herds.

BACKGROUND: Lawsonia intracellularis is causing diarrhea, poor growth and sudden death in pigs. It can be found in most pig populations leading to large economic losses worldwide. Many potential risk factors for the occurrence of disease or seropositivity have been described. The current study therefore focused on herd characteristics in European countries associated with direct detection of the pathogen determined by quantitative polymerase chain reaction. RESULTS: A median number of less than 30 nursery pigs per pen was correlated to less positive nursery pigs (p < 0.01) and generally less samples positive per herd (p < 0.05) as well as a lower median of genome equivalents determined per herd (p < 0.05). Routine use of zinc oxide at/ around weaning, which was mentioned by 41.0% of all farmers, was correlated to higher number of positive nursery pigs (p < 0.01) as well as higher median genome equivalents determined per herd (p < 0.05). Slatted flooring of more than 78.0% of the surface in nursery units was correlated to lower number of positive animals (p < 0.05) and a lower median of genome equivalents per herd (p < 0.05). A weight of more than 7.8 kg at weaning was correlated to a higher number of positive growing pigs (p < 0.05) as well as general higher number of positive samples/ herd (p < 0.01). CONCLUSIONS: Weaning and subsequent accommodation of nursery pigs seem to be of particular importance in prevention of infection with Lawsonia intracellularis and the spread of the pathogen within the herd.

Peracute selenium toxicosis followed by sudden death in growing and finishing pigs.

Fattening pigs (n = 751) showed progressive apathy, paralysis, and sudden death after accidental ingestion of excessive concentrations of selenium in mineral feed. Selenium concentrations of 1.09 to 1.32 mg/L in the serum confirmed the diagnosis. Within 3 d all pigs had died spontaneously or were euthanized due to the grave prognosis and on welfare grounds.

Seroprevalence of atypical porcine pestivirus in a closed pig herd with subclinical infection.

Atypical porcine pestivirus (APPV) has recently been reported to be associated with congenital tremor in newborn piglets. Only limited information is available about the prevalence at herd level in endemically infected herds. Therefore, the aim of this study was to determine the within-herd prevalence of APPV in a sub-clinically infected sow herd in Switzerland and to analyse associations between the serological status as well as the age and sex of the pigs, litter number and days after the last insemination. In a census sampling, blood was collected from 125 sows, aged 180 days or older, and six boars. Sera were examined applying an indirect APPV-specific ELISA to individual sera and an APPV RT-PCR targeting the NS3 encoding regions of APPV to pools of five. The APPV antibody status was classified into low (S/P value ≤ 0.5), intermediate (S/P value = 0.5-1) and high reactivity (S/P value > 1.0). None of the pooled serum samples was positive for specific genome fragments of APPV. Of the 131 samples, 53.4% were highly reactive, 39.7% showed an intermediate reactivity, and 6.9% showed a low reactivity in the indirect ELISA, that is, were serologically negative. Significant associations between the S/P values and the age of the pigs (p < .001), the litter number (p < .001) and the numbers of days after the last insemination (p = .0188) were observed. The results indicate that this sow herd was previously infected with APPV, while viremia was not detected in any of the adult pigs. This might explain the absence of clinical signs in the suckling pigs. Potential reinfection and circulation of APPV in this sow herd might be due to semen from commercial boar studs or APPV-positive animals in the absence of specific clinical signs.

Risk factors for the infection with Brachyspira hyodysenteriae in pig herds.

Swine dysentery (SD), caused by infection with Brachyspira hyodysenteriae, is a serious disease in pig production worldwide. Quantitative risk factors triggering the occurrence of infection are unknown. The present case-control study aimed at identifying major risk factors related to presence of B. hyodysenteriae in pig herds. Twenty case herds and 60 randomly selected control herds with a minimum herd size of '10 sows/ 80 fattening pigs' were examined by means of a questionnaire-based interview and a herd examination. Herds with previous eradication of SD were excluded. Logistic regression models revealed that the 'positive/suspicious SD status of source herds', the regular application of treatment, purchasing more than 4 batches/ year, contact to foxes, diagnostics performed during last 12 months, liquid feeding systems, rats on farm, and >250 fatting places were associated with higher chances of a herd to be infected. On the contrary, having different sources of grower pigs within one batch, the presence of raptor birds and the presence of martens in the region were associated with fewer chances of being infected. The final multivariable logistic regression model identified purchasing more than 4 batches/ year (OR = 7.5, 95 % CI 1.8-54.3) and contact to foxes (OR = 5.9; 97.5 % CI 1.2-34.6) as the two main risk factors in our study. 'More than 4 batches/ year' implies continuous herd management supporting persistence of B. hyodysenteriae in an infected herd, but also increased number of purchases each increasing the risk of B. hyodysenteriae introduction by carrier pigs or transport vehicles. Foxes might be infected with B. hyodysenteriae by feeding on positive piglets and rodents. Besides, 'contact to foxes' might represent a lack in biosecurity. In conclusion, the risk factors detected underline the importance of biosecurity in SD prevention and control.

Modeling Economic Effects of Vaccination Against Porcine Reproductive and Respiratory Syndrome: Impact of Vaccination Effectiveness, Vaccine Price, and Vaccination Coverage.

Porcine reproductive and respiratory syndrome (PRRS) causes substantial financial losses in pig farms and economic losses to societies worldwide. Vaccination against PRRS virus (PRRSV) is a common intervention in affected farms. The aim of this study was to assess the economic impact and profitability of potential new PRRS vaccines with improved efficacy at animal, herd, and national level. Two vaccination strategies were modeled; (i) mass vaccination of sows only (MS) and (ii) mass vaccination of sows and vaccination of piglets (MSP), comprising different scenarios of vaccine effectiveness, vaccine price, and vaccination coverage. A farrow-to-finish farm with 1,000 working sows from a pig-dense region in Germany served as an example farm. Financial benefits were obtained from gross margin analyses and were defined as difference in gross margin between a PRRSV-infected farm without vaccination (baseline) and with vaccination (intervention). Financial benefits were highest if both sows and piglets (MSP) were vaccinated. In these scenarios, median annual net benefits per working sow ranged from €170 to 340. If sows only were vaccinated (MS), estimated benefits attributable to vaccination were between €148 and 270. Decisive variables for the estimation of national level benefits were the number of farmers switching from existing to a better protecting vaccine, the number of previously non-vaccinating herds adopting the new vaccine, and the effectiveness of the new vaccine relative to those already available. Benefits were greatest when the new vaccine was adopted by previously non-vaccinating herds. The analyses showed that vaccination against PRRS was beneficial for all modeled scenarios. The magnitude of benefits derived from vaccination was more susceptible to changes in vaccination effectiveness than to vaccine price changes. This study provides evidence to support future vaccine development. The estimates indicate that the introduction of more efficient vaccines might lead to substantial financial benefits, is of socio-economic importance and that new vaccines might significantly contribute to the reduction of disease burden.

Assessment of folate and cobalamin concentrations in relation to their dependent intracellular metabolites in serum of pigs between 6 and 26 weeks of age.

Folate (vitamin B9) and cobalamin (vitamin B12) play an important role in amino acid metabolism, nucleic acid synthesis, and methyl group transfer. Two intracellular enzymes, methionine synthase and methylmalonyl-CoA mutase, are folate and/or cobalamin-dependent, respectively. At the cellular level, a lack of folate and cobalamin leads to accumulation of serum homocysteine (HCY) and a lack of cobalamin leads to increased methylmalonic acid (MMA) concentrations. Altered serum HCY and MMA concentrations can influence amino acid metabolism and nucleic acid synthesis in pigs. Therefore, we aimed to evaluate serum folate, cobalamin, HCY, and MMA concentrations in postweaning pigs between 6 and 26 weeks of age. Serum samples from 12 pigs collected at week 6, 7, 8, 9, 10, 14, 18, 22, and 26 as part of an unrelated study were analyzed. Serum folate (p < .0001), cobalamin (p = .0001), HCY (p < .0001), and MMA (p < .0001) concentrations differed significantly during the postweaning period between 6 and 26 weeks of age; with significantly higher serum HCY (at weeks 6 and 7 compared to weeks 9, 14, 18, 22, and 26) and MMA concentrations (at weeks 6, 7, and 8 compared to weeks 14, 18, 22, and 26) and an overall decrease of serum MMA concentrations from week 6 to week 14 in the pigs studied. This study suggests age-dependent changes in intracellular folate- and cobalamin-dependent metabolites (i.e., HCY and MMA) in pigs between 6 and 26 weeks of age, possibly reflecting decreased availability of intracellular folate and/or cobalamin for amino acid metabolism, nucleic acid synthesis, and methyl group transfer.

A comparison of the carcase characteristics of pigs immunized with a 'gonadotrophin-releasing factor (GnRF)' vaccine against boar taint with physically castrated pigs.

Evaluating the effect of using a GnRF vaccine against boar taint on the carcase characteristics of boars, vaccinated pigs were compared with physically castrated. In total, 554 male pigs were randomly assigned to treatment groups. T01 comprised physically castrated pigs in the first week of life, T02 comprised pigs vaccinated twice before slaughtering. There was neither significant difference between the groups in terms of average liveweight nor in the hot carcase weight. The mean dressing percentage was 1.5% higher for T01 than for T02 (P<0.0001). The lean meat percentage was significantly higher in T02 (P<0.0001). Backfat and backmuscle thickness were significantly higher in T01 (P<0.0001 and P=0.0099, respectively). Within the EUROP grading vaccinated pigs were in favour (P=0.0034). There were no significant differences using the AutoFOM system: weights of the boned ham, boned shoulder and loin (P=0.5102, P=0.8881 and P=0.1919, respectively). The weight of the belly was significantly higher (P=0.0042) in T01 while the lean meat percentage of belly was significantly higher (P<0.0001) in T02.