Ioannis Arsenakis

Piglets are highly susceptible to iron deficiency. This randomized clinical trial evaluated the effectiveness of four iron dosing schemes in preventing anemia. Two herds with different farrowing management systems were included. In each herd, 40 litters (6 piglets/litter) were selected on day 3 of age. A 2 × 2 factorial design was applied, combining two intramuscular iron dextran injection schemes [37.5 mg Fe/kg (low injection; LI) or 150 mg Fe/kg (high injection; HI)] with two oral ferrous sulphate feed supplementation schemes [125 mg Fe/kg (low feed; LF) or 200 mg Fe/kg (high feed; HF)]. Blood samples were collected at 4 and 20 days of age, and piglets were weighed at 3 and 20 days. Data were analyzed using linear mixed models, with significance set at p < 0.05. In Herd A, HI-LF piglets showed increased body weight, whereas no growth differences were observed in Herd B. Creep-feed intake did not differ between treatments. HI consistently improved red-cell indices in Herd A, while in Herd B LI piglets initially showed higher values at day 4, but HI piglets surpassed them by day 20. Leukocyte responses were limited. High-dose iron injections were effective in preventing anemia, while oral supplementation had minimal impact.

Background: Porcine circovirus 2 (PCV2) and Mycoplasma hyopneumoniae (M hyo) are two of the most important swine pathogens with variable clinical presence in swine farms globally, affecting health and performance of pigs under field conditions. The primary objective of this study was to assess the efficacy of a ready to use intradermal (ID) vaccine (Porcilis PCV M Hyo ID, MSD Animal Health, The Netherlands) against PCV2 associated disease and M hyo associated enzootic pneumonia under practical (field) conditions. In addition, the safety of the test product was clinically assessed, as the study animals were examined for general and local side effects after vaccination. A total of 678 animals in a Greek farrow to finish farm were equally divided in two trial groups (test and control group). Test group animals received the test vaccine at the age of three weeks, while control group animals remained unvaccinated. Parameters regarding health [lung lesion score (LLS) and pleurisy scoring, PCV2 viraemia and shedding] and performance [body weight (BW), average daily weight gain (ADWG)] were recorded and evaluated. Results: Vaccination improved the ADWG during both the finishing period (improvement by 34 g; p < 0.0001), and the overall period (increase by 24 g; p < 0.0001). Moreover, reduced mean LLS values (p < 0.0001), as well as reduced percentage of animals with pleurisy (p = 0.0082) and a decrease in PCV2 viraemia (p < 0.0001) and viral shedding (p = 0.0181) were observed in vaccinated animals when compared with the unvaccinated controls. As regards safety, a slight local skin reaction at the site of vaccination was detected and in two pigs a mild systemic reaction was reported with full recovery. Conclusions: Findings suggested that the test vaccine is safe and effective against both PCV2 and M hyo associated diseases in vivo, thus it’s use as part of a vaccination programme under field conditions is expected to improve respective health and performance parameters in pigs.

A review of organic pig production in Greece was carried out. The aim was to present updated information on the production, development and health status of organic pig farming in Greece and potential prospects for sustainability and future development. The indigenous Greek Black Pig is the main breed reared in Greek organic pig farms. All the reasons why Greek Black Pig breeding is ideal for organic farming are mentioned. Furthermore, respiratory and parasitic infections are the most common health problems, while high piglet mortality rates are the main welfare issue in Greek organic pig farming. Concerns about how farmers and authorities should utilize the demands of modern consumers are discussed.

This study investigated Mycoplasma hyopneumoniae colonisation and lung lesions at slaughter in pigs from vaccinated (V) and non‐vaccinated (NV) sows, in two herds (A and B). In each herd, two sow batches were V against M. hyopneumoniae with a commercial bacterin at six and three weeks before farrowing and two sow batches remained NV. From each sow batch, laryngeal swabs were collected from the litters of five primiparous sows at weaning and seven days post‐weaning. All samples were tested for M. hyopneumoniae by nested PCR. In total, 488 piglets were sampled. At slaughter, the extent of Mycoplasma ‐like pneumonia lesions (lung lesion score (LLS)) was assessed. The colonisation rates with M. hyopneumoniae at weaning and seven days post‐weaning were (V‐A=14.2, NV‐A=20.0 (P=0.225); V‐B=0.9, NV‐B=0.8 (P=0.948)) and (V‐A=0.8, NV‐A=7.0 (P=0.039); V‐B=1.8, NV‐B=2.5 (P=0.738)), respectively. The average LLS (in per cent) was V‐A=15.5, NV‐A=26.4 (P=0.021); V‐B=9.7, NV‐B=8.4 (P=0.541). In conclusion, in herd A, with a substantially higher level of piglet colonisation at weaning than herd B, offspring from V sows had a significantly lower colonisation rate seven days post‐weaning and a significantly lower LLS at slaughter compared with the offspring of the NV sows. This implies that sow vaccination might be useful for control of M. hyopneumoniae infections, although significant results may not be achieved at all times (such as in herd B).

This study was conducted in a commercial 1000‐sow herd facing recurrent exudative epidermitis (EE) outbreaks during the nursery period and assessed the efficacy of autogenous vaccination in controlling such outbreaks. The vaccine was produced using three Staphylococcus hyicus isolates recovered from affected pigs shortly before the onset of the study. All of those isolates were positive for the exh B gene, which encodes the exfoliative toxin type B (ExhB). From four consecutive farrowing batches of sows, two batches were vaccinated (V) against S hyicus at five and two weeks before farrowing, and two sow batches remained non‐vaccinated (NV). Vaccination efficacy was primarily determined by the levels of metaphylactic antimicrobial usage, and the morbidity and mortality data for the pigs of the V and NV sows. The total amount of antimicrobials used metaphylactically against EE in pigs among the V and NV farrowing batches was 39,600 and 88,550 mg, respectively. The used daily dose pig to animal daily dose pig ratio for the V and NV batches were 1.31 and 1.79, respectively (a ratio of 0.8 to 1.2 is indicative of correct dosing). The morbidity and mortality rates were V=6.50 and NV=14.36 (P=0.008), and V=2.59 and NV=5.02 (P=0.000), respectively. To conclude, autogenous vaccination of the sows with a vaccine based on exh B‐positive S hyicus isolates reduced metaphylactic treatment with antimicrobials as well as the morbidity and mortality rates in weaned pigs compared with pigs from NV sow batches.

The mycotoxin deoxynivalenol (DON) is highly prevalent in cereals in moderate climates and therefore pigs are often exposed to a DON-contaminated diet. Pigs are highly susceptible to DON and intake of DON-contaminated feed may lead to an altered immune response and may influence the pathogenesis of specific bacterial diseases. Therefore, the maximum guidance level in feed is lowest in this species and has been set at 900 μg/kg feed by the European Commission. This study aimed to determine the effect of in-feed administration of a moderately high DON concentration (1514 μg/kg) on the severity of an experimental Mycoplasma hyopneumoniae (M. hyopneumoniae) infection in weaned piglets. Fifty M. hyopneumoniae-free piglets were assigned at 30 days of age [study day (D)0] to four different groups: 1) negative control group (NCG; n = 5), 2) DON-contaminated group (DON; n = 15), 3) DON-contaminated and M. hyopneumoniae-inoculated group (DONMHYO; n = 15), 4) M. hyopneumoniae-inoculated group (MHYO; n = 15). The piglets were fed the experimental diets ad libitum for five weeks and were monitored during this period and euthanized at day 35 [27 days post infection (DPI)] or 36 (28 DPI). The main parameters under investigation were macroscopic lung lesions (MLL) at euthanasia, respiratory disease score (RDS) from day 8 until day 35, histopathologic lesions and log copies of M. hyopneumoniae DNA detected by qPCR, determined at the day of euthanasia. No significant difference was obtained for MLL at euthanasia, RDS (8–35), histopathologic lung lesions and log copies of M. hyopneumoniae DNA in the DONMHYO and MHYO group and consequently, no enhancement of the severity of the M. hyopneumoniae infection could be detected in the DONMHYO compared to the MHYO group. Under present conditions, the findings imply that feed contaminated with DON (1514 μg/kg) provided to weaned pigs for five weeks did not increase the severity of an experimental M. hyopneumoniae infection. Further research is needed to investigate the impact of DON on M. hyopneumoniae infections in a multi-mycotoxin and multi-pathogen environment.

Mycoplasma hyopneumoniae (M. hyopneumoniae) is the primary agent of enzootic pneumonia in pigs. Pigs are often infected with different M. hyopneumoniae strains. This study assessed the efficacy of vaccination against experimental infection with two genetically different M. hyopneumoniae strains in weaned piglets. At 33 days of age (D0), 45 M. hyopneumoniae-free piglets were randomly assigned to three different groups: 1) negative control group (NCG; n = 5): not vaccinated, not infected, 2) positive control group (PCG; n = 20): not vaccinated, infected, and 3) vaccination group (VG; n = 20): single vaccination with an inactivated whole-cell M. hyopneumoniae vaccine (Hyogen®, Ceva) (D1), infected. The PCG and VG were endotracheally inoculated with 7 × 107 CCU in 7 ml of the highly virulent M. hyopneumoniae strain F7.2C (D24) and 7 × 107 CCU in 7 ml low virulent strain F1.12A (D25). A respiratory disease score (RDS) was assessed from D24 until D53. At D53 (euthanasia), macroscopic lung lesions (MLL) were scored, log copies of M. hyopneumoniae DNA (qPCR) and IL-1 and IL-6-concentrations (ELISA) on bronchoalveolar lavage fluid were determined. The RDS and MLL at euthanasia were respectively 0, 1.20 and 0.55 (P < 0.001) and 0, 7.56 and 0.68 (P < 0.001) for NCG, PCG and VG, respectively. The qPCR results for PCG and VG were 3.99 and 1.78 log copies (P < 0.001), respectively, with a significant difference between PCG and VG. The IL-1 and IL-6 results at euthanasia for NCG, PCG and VG were 17.61, 1283.39 and 53.04 pg/ml (P < 0.001) and 148.10, 493.35 and 259.80 pg/ml (P = 0.004), respectively with a significant difference between PCG and VG. Vaccination with Hyogen® in pigs was efficacious against an experimental challenge with both a low and highly virulent M. hyopneumoniae strain as the vaccinated pigs coughed significantly less, and showed significantly less lung lesions compared to the non-vaccinated challenged pigs: the vaccinated animals showed a 52.9% lower RDS and 91.0% lower MLL compared to the PCG. In the bronchoalveolar lavage fluid collected at the necropsy of the vaccinated pigs, a significantly lower amount of M. hyopneumoniae-DNA and a significantly lower IL-1 and IL-6 concentration was found compared to the pigs of the PCG.