A study of associations between gastric ulcers and the behaviour of finisher pigs

Gastric ulcers in finishing pigs: the evaluation of selected non-dietary risk factors and impact on production performance

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.

Inclusion of silage in diets to fattening pigs: effect on gastric ulcers and skin lesions

Limited access to high-quality feed protein for pigs has made it necessary to evaluate new protein sources that both promote sustainable pig production and meet the nutritional requirements of pigs. Providing pigs with roughage has positive effects on their behaviour and gut health. However, roughage is seldom given as a part of the pigs' diet and often has a long straw length. Knowledge is lacking on the effect of feeding silage with smaller particle size and as a part of the pigs' diet on pig behaviour and welfare. This study evaluated the influence of feeding fattening pigs silage with different particle sizes on aggressive encounters, measured as the number of skin lesions, and on the occurrence of gastric lesions and ulcers. In total, 128 Swedish Yorkshire × Hampshire pigs were fed either a commercial control feed without silage (Pellet-C), or silage mixed with commercial feed, either in a pellet (Pellet-S) or in a total mixed ration (TMR) with chopped (TMR-Ch) or intensively treated silage (TMR-Ex). Skin lesions were assessed twice in the study according to the Welfare Quality® protocol. The first assessment was performed when the pigs were 105 days old and the second assessment at 132 days of age. Gastric lesions were examined in both the pars oesophagea and the pars glandularis region of the stomach. Stomachs were collected after slaughter, and gastric lesions were scored based on established scoring criteria. There was a treatment × assessment interaction on the number of skin lesions on the ear (P = 0.049). Apart from this interaction, no other effect of treatment on the number of skin lesions could be observed between the treatments or the assessment occasions. Treatment had a clear effect on the occurrence of gastric lesions and pigs fed the fresh silage (TMR-Ch and TMR-Ex) had a lower occurrence of gastric lesions and ulcers compared to the pelleted treatments (Pellet-C and Pellet-S) (P = 0.001). This study could not show any clear reduction effect of dietary silage inclusion on skin lesions. However, feeding silage in TMR significantly reduced the occurrence of stomach ulcers.

A Preliminary Study on the Relationship between Gastric Lesions and Anti-Inflammatory Drug Usage in Heavy Pigs

Gastric lesions in pigs cause welfare and economic losses. Their prevalence in heavy pigs reared for premium products (e.g., Parma ham) requires further investigation. Stress, nutrition, and farm management are known risk factors, but the effects of steroidal and non-steroidal anti-inflammatory drugs (NSAIDs) are largely unknown. The aim of this study was to evaluate the prevalence of gastric lesions in Italian heavy pigs and their possible association with the use of anti-inflammatory drugs. A total of 9371 pig stomachs from 76 farms were evaluated. Among these, 20.3% showed no lesions, while 30.7%, 42.1%, and 6.8% were scored 1, 2 and 3, respectively. A tendency for an inverse relationship with farm size emerged. The use of steroids and NSAIDs was estimated by calculating a treatment incidence per 1000 (TI1000) in a subset of 36 farms. At least one prescription for NSAIDs and/or steroids was found in 80.6% of the farms (55.6% used NSAIDs and 63.9% used steroids). Median TI1000 was 0.07 (range: 0-30.1) and 0.18 (range: 0-6.2) for NSAIDs and steroids, respectively. Gastric scores were positively associated with NSAID use, but not with steroid use. Although the role of these drugs in gastric lesions needs to be further clarified, these findings suggest a cautious use of non-selective NSAIDs.

Prioritization of Farm Animal Welfare Issues Using Expert Consensus

Prioritization of animal welfare issues can help identify which areas most require research funding and raise awareness of best practices. A modified Delphi method was used to obtain expert opinion on the highest priority welfare issues for UK farmed livestock. Fifty-eight UK-based experts were recruited onto the study, with a minimum of 3 years experience of working with either cattle, pigs, poultry, or small ruminants (12-16 experts per group). Experts were chosen to represent a broad range of opinions. Two rounds of surveys were conducted online using Online Survey, and the final round was an in-person workshop with 21 experts. In the first survey, experts were provided with a comprehensive list of species-specific welfare issues derived from the literature. Participants were asked to score each welfare issue, for (i) severity, (ii) duration, and (iii) prevalence on a 6-point Likert scale. The results of the first survey were reviewed and the welfare issues which scored a neutral-to-high response (scores 3-6) were carried forward. In round 2, participants were asked whether they agreed or disagreed with the rankings that were made from the results of round 1. The final stage of the process was a workshop, which consisted of a combination of group exercises and discussions, to reach the final consensus. Welfare priority lists were divided into two categories: severity/duration, and prevalence, to identify the priority welfare issues affecting individual animals and the population, respectively. Across all farmed species common concerns were inadequate or inappropriate nutrition, inability of stockpeople to recognize or treat welfare issues (such as pain or behavioral problems), lameness, chronic or endemic health issues, euthanasia and mortality and morbidity of neonates. Specific concerns related to behavioral restriction and damaging or abnormal behavior in pigs, poultry and dairy animals, inadequate housing for pigs and poultry, consequences of breeding decisions in pigs and poultry, and lack of access to veterinary care in sheep and beef. This Delphi process resulted in consensus on the most significant welfare challenges faced by UK livestock species and can help to guide future research and education priority decisions.