Porcine respirovirus 1 (PRV1) is also known as porcine parainfluenza virus 1 (PPIV1). The prevalence and the role of PRV1 infections for pig health is largely unknown. In order to assess the PRV1 prevalence in Poland, nasal swabs and oral fluids collected from pigs from 30 farms were examined with RT real-time PCR. Additionally, IAV and PRRSV infection statuses of PRV1-positive samples were examined. The results showed that the virus is highly prevalent (76.7% farms positive) and different patterns of PRV1 circulation in herds with mild–moderate respiratory disease were observed. Co-infections with IAV and PRRSV were infrequent and detected in 8 (23.5%) and 4 (11.8%) out of 34 PRV1-positive nasal swab pools from diseased pens, respectively. In one pen PRV1, IAV, and PRRSV were detected at the same time. Interestingly, PRV1 mean Ct value in samples with co-infections was significantly lower (29.8 ± 3.1) than in samples with a single PRV1 infection (32.5 ± 3.6) (p < 0.05), which suggested higher virus replication in these populations. On the other hand, the virus detection in pig populations exhibiting respiratory clinical signs, negative for PRRSV and IAV, suggests that PRV1 should be involved in differential diagnosis of respiratory problems.
Influenza A virus (IAV) is a single-stranded, negative-sense RNA virus and a common cause of seasonal flu in humans. Its genome comprises eight RNA segments that facilitate reassortment, resulting in a great variety of IAV strains. To study these processes, the genetic code of each segment should be unraveled. Fortunately, new third-generation sequencing approaches allow for cost-efficient sequencing of IAV segments. Sequencing success depends on various factors, including proper sample storage and processing. Hence, this work focused on the effect of storage of oral fluids and swIAV sequencing. Oral fluids (n = 13) from 2017 were stored at −22 °C and later transferred to −80 °C. Other samples (n = 21) were immediately stored at −80 °C. A reverse transcription quantitative PCR (RT-qPCR) pre- and post-storage was conducted to assess IAV viral loads. Next, samples were subjected to two IAV long-read nanopore sequencing methods to evaluate success in this complex matrix. A significant storage-associated loss of swIAV loads was observed. Still, a total of 17 complete and 6 near-complete Polish swIAV genomes were obtained. Genotype T, (H1avN2, seven herds), P (H1N1pdm09, two herds), U (H1avN1, three herds), and A (H1avN1, 1 herd) were circulated on Polish farms. In conclusion, oral fluids can be used for long-read swIAV sequencing when considering appropriate storage and segment amplification protocols, which allows us to monitor swIAV in an animal-friendly and cost-efficient manner.
Sudden death caused by the acute form of gastric ulceration has developed into a widely recognised health and welfare problem. The importance of different triggering factors is poorly understood. The study was carried out on finishers slaughtered in Poland. The collected animal-level data were transformed to a herd-level dataset, which included 27 predictor variables. From a total of 32,264 pig stomachs examined, 23,188 (71.9%) had gastric lesions. Total of 17,703 organs (54.9%) had ulcers. Scores 1 (hyperkeratotic) and 2 (erosions) were observed in 2958 (9.2%) and 2527 (7.8%), respectively. A significant (p < 0.05) association of the ulcer prevalence was found for a number of variables. Raising the level of protein significantly (p = 0.04) increased (ρ = 0.22) the occurrence of gastric ulcers. The addition of wheat bran (p = 0.02) and its growing share in feed composition had the contrary effect (ρ = −0.27). Feeding pelleted feed was significantly associated (p = 0.001) with the higher prevalence of the disease, opposite to liquid feeding (p = 0.0002) and supplementation of a mycotoxin deactivator (p = 0.0008). Although, the immediate transition from one feeding system to another in most of the farms is impossible, the addition of materials such as wheat bran, and routine supplementation with mycotoxin deactivators may be a practical and relatively low-cost solution.
Background: The complex aetiology of gastric lesions in pigs remains largely unknown and effective preventive measures and pharmaceutical treatment of the disease have not been developed yet. Regardless of the fact that the overwhelming majority of previous research works dealing with gastric ulceration in pigs focused on the role of the nutritional determinants, including chemical composition of feeds, cereal type, finely ground pelleted diets, and feed additives, conclusions presented therein remain highly ambiguous. Thus, the purpose of this study was to evaluate the impact of the disease on production performance, and investigate the influence of selected non-dietary risk factors on the prevalence of gastric alterations in finishing pigs reared under conditions of 11 modern farms located in Poland.Results: A total number of 26,043 finishing pigs was examined. 15,228 (58.47%) had gastric ulcers. Intact stomachs were detected in 6176 animals (23.71%). Parakeratosis and erosion were observed in 2551 (9.80%) and 2088 (8.02%), respectively. Among eight continuous variables two were found to be significantly associated with prevalence of the gastric ulcer: the growing number of animals in the herd, which was negatively correlated (P = 0.002; ρ = -0.37), and the growing average entry weight of animals transported to the finisher farm (P = 0.047; ρ = 0.24), which increased the risk of gastric ulcers prevalence. Among 12 nominal variables, problems with the quality of farm management (P = 0.041), and usage of straw as a bedding material (P = 0.002) were identified as determinants significantly associated with occurrence of the analysed health problem.Conclusions: Among 20 non-nutritional variables analysed in our study only few factors were found to be associated with the prevalence of the disease. The impact of broadly understood management issues on gastric health in finishing pigs deserves further research.
Porcine parainfluenza virus 1 (PPIV-1) is a recently emerged respirovirus closely related to human parainfluenza virus 1 (HPIV-1) and Sendai virus (SenV). PPIV-1 has been detected in Asia, the Americas and Europe, but knowledge on its epidemiology and genetic diversity is very limited. In the present study, the complete nucleotide sequences of the fusion (F)-protein gene obtained from samples from 12 Polish and 11 US herds were analysed and compared to previously available genetic data from the Americas, Asia and Europe. The existence of two distinct clades was observed, grouping European sequences and one Hong Kong sequence (clade 1), or one American sequence and three Asian sequences (clade 2). The mean genetic distances measured with the p-distance were 0.04 (S.E., 0.000) within both clades, and 0.095 (S.E., 0.006) between the clades. Moreover, two distinct clusters of highly similar sequences were identified, which corresponded to the geographically distant nurseries and finishing units, from three pig flows within one Polish pig-production company. The obtained data indicate that the two PPIV-1 lineages may have evolved independently in Europe and America. More studies, particularly involving Asian viruses, are necessary to understand the virus’ emergence and epidemiology and the role of carriers in the spread of PPIV-1.
Specific anatomy of the porcine stomach results in a high risk of ulceration in the pars oesophagea. A fully developed ulcer leads to intermittent gastrointestinal bleeding followed by clinical symptoms of chronic pain; thus, gastric ulceration in pigs causes significant production losses and serious welfare problems. Nowadays, gastric ulceration is common in domestic pigs throughout the world, but a great deal of attention has been directed at finishers. This paper was intended to provide new data on the prevalence of the disease in commercially reared highly prolific sows. The study was carried out on 329 culled sows from four commercial farms located in Northern Poland. The severity of gross pathological lesions of pars oesophagea was assigned to grade 0 (no lesions), 1 (parakeratosis), 2 (erosion), or 3 (gastric ulceration with or without stenosis) by a veterinary practitioner. Abattoir analysis revealed 66.6% of sows’ stomachs with some degree of alterations. Gastric ulceration was detected in 45.5% of examined organs. Parakeratosis and erosion were found in 1.2 and 15.8% of stomachs, respectively. The investigation did not find any oesphageal strictures. Our investigation of the problem in high health status hyper-prolific sows showed the lowest prevalence of gastric lesions (i.e., ulcerative and preulcerative alterations collectively) compared to earlier studies but the highest percentage of gastric ulcers. The results indicate that gastric ulcers may be a highly prevalent and underestimated welfare issue in sows in modern pig production, worth further studies focusing on particular risk factors related to feeding, genetics, management issues, and sows longevity.