Development of pig welfare assessment protocol integrating animal-, environment-, and management-based measures

Effects of removing in-feed antibiotics and zinc oxide on the taxonomy and functionality of the microbiota in post weaning pigs

BACKGROUND

Post weaning diarrhoea (PWD) causes piglet morbidity and mortality at weaning and is a major driver for antimicrobial use worldwide. New regulations in the EU limit the use of in-feed antibiotics (Ab) and therapeutic zinc oxide (ZnO) to prevent PWD. New approaches to control PWD are needed, and understanding the role of the microbiota in this context is key. In this study, shotgun metagenome sequencing was used to describe the taxonomic and functional evolution of the faecal microbiota of the piglet during the first two weeks post weaning within three experimental groups, Ab, ZnO and no medication, on commercial farms using antimicrobials regularly in the post weaning period.

RESULTS

Diversity was affected by day post weaning (dpw), treatment used and diarrhoea but not by the farm. Microbiota composition evolved towards the dominance of groups of species such as Prevotella spp. at day 14dpw. ZnO inhibited E. coli overgrowth, promoted higher abundance of the family Bacteroidaceae and decreased Megasphaera spp. Animals treated with Ab exhibited inconsistent taxonomic changes across time points, with an overall increase of Limosilactobacillus reuteri and Megasphaera elsdenii. Samples from non-medicated pigs showed virulence-related functions at 7dpw, and specific ETEC-related virulence factors were detected in all samples presenting diarrhoea. Differential microbiota functions of pigs treated with ZnO were related to sulphur and DNA metabolism, as well as mechanisms of antimicrobial and heavy metal resistance, whereas Ab treated animals exhibited functions related to antimicrobial resistance and virulence.

CONCLUSION

Ab and particularly ZnO maintained a stable microbiota composition and functionality during the two weeks post weaning, by limiting E. coli overgrowth, and ultimately preventing microbiota dysbiosis. Future approaches to support piglet health should be able to reproduce this stable gut microbiota transition during the post weaning period, in order to maintain optimal gut physiological and productive conditions.

Clinical characterization of a hypersensitivity mixed bacterial and fungal dermatitis in a translational model of porcine NASH

Introduction

The development of animal models of chronic liver disease via diet modification is a promising avenue for translational research but can lead to unexpected side effects that impact model adoption. While these side effects are well characterized in rodent models of nonalcoholic steatohepatitis (NASH), limited knowledge of these effects exists for novel porcine models of NASH. To close this gap, the present study investigates the side effects of diet-based NASH induction in pigs, with a systematic analysis of the pathologic mechanisms underlying dermatitis development and evaluation of treatment approaches.

Method

Twelve pigs (10 large domestic pigs, 2 Goettingen minipigs) were fed a methionine- and choline-deficient, high-fat diet for 8 weeks to induce NASH. A retrospective review of each animal's clinical record was performed to identify the side effects of the diet. Following the identification of diet-associated dermatitis, severity was judged by using a novel gradation system that characterized the individual lesions and body regions resulting in a cumulative evaluation. In addition to this clinical assessment, the etiology of the dermatitis was investigated via histopathologic and microbiologic testing. Furthermore, the success of prophylactic and therapeutic treatment approaches was evaluated by considering dermatitis development and clinical course.

Results

All study animals demonstrated unexpected side effects of the methionine- and choline-deficient, high fat diet. In addition to marked dermatitis, study pigs showed impaired weight gain and developed steatorrhea and anemia. Based on the skin gradation system, five animals developed severe dermatitis, four animals moderate dermatitis, and three animals mild diet-associated dermatitis. Histological and microbiological evaluation of the affected skin showed signs of a hypersensitivity reaction with secondary infection by bacteria and fungi. The analysis showed that preemptive bathing extended the lesion-free duration by nearly 20 days. Furthermore, bathing in combination with a targeted antibiotic treatment represented a helpful treatment approach for diet-associated dermatitis.

Conclusion

The provision of a methionine- and choline-deficient, high fat diet represents an effective approach for inducing NASH liver disease in pigs but predisposes study animals to multiple side effects. These side effects are universal to animals on study but can be adequately managed and do not represent a significant limitation of this model.

Air Quality Assessment in Pig Farming: The Italian Classyfarm

On 24 September 2019, the Ministry of Health issued an explanatory circular containing clarifications on the implementation methods of the National Improvement Plan for the application of Legislative Decree 122/2011. The Plan states that "In all farms where weaning or fattening pigs are raised and in breeding farms which wean piglets (excluding those for self-consumption), a risk assessment is carried out by the veterinarian on the basis of three levels: insufficient, room for improvement and optimal". ClassyFarm, a risk assessment tool for livestock farming, is applied in Italy to evaluate the level of welfare and management of animals from a variety of points of view. Essentially, the categorization risk introduced by ClassyFarm in pig farming depended on the obligation stated by the EU in Decree 122/2011 to avoid tail docking in piglets and, at the same time, to reduce the stressor aspects able to induce aggressive behavior among pigs, improving the welfare and health status of animals. Since ClassyFarm evaluates many aspects of the management of animal farming, our aims in this review are to discuss the topic from an environmental point of view: (1) to frame the indications of ClassyFarm to make a farm risk assessment based on pigs' welfare; (2) to review environmental quality assessment in pig farms, and its repercussions on animal health and welfare; (3) to describe the most used sampling techniques of air pollutants measurements.

Correlation of Animal-based parameters with environment-based parameters in an on-farm welfare assessment of growing pigs

Nine pig farms were evaluated for the welfare quality in Korea using animal- and environment-based parameters (particularly air quality parameters) during the winter of 2013. The Welfare Quality^® (WQ^®) protocol consists of 12 criteria within four principles. The WQ^® protocol classifies farms into four categories ranging from ‘excellent’ to ‘not classified’. Each of these criteria has specific measures for calculating scores. Calculations for the welfare scores were conducted online using the calculation model in the WQ^® protocol. Environment-based parameters like microclimate (i.e., temperature, relative humidity, air speed, and particulate matter), bacteria (total airborne bacteria, airborne total coliform, and airborne total Escherichia coli), concentration of gases (carbon dioxide, ammonia, and hydrogen sulfide) were measured to investigate the relationship between animal- and environment-based parameters. Correlations between the results of animal- and environment-based parameters were estimated using spearman correlation coefficient. The overall assessments found that five out of nine farms were ‘acceptable’, and four farms were ‘enhanced’; no farm was ‘not classified’. The average score for the four principles across the nine farms, in decreasing order, were ‘good feeding’ (63.13 points) > ‘good housing’ (59.26 points) > ‘good health’ (33.47 points) > ‘appropriate behaviors’ (25.48 points). In the result of the environment aspect, the relative humidity of farms 2 (93.4%), 3 (100%), and 9 (98%) was much higher than the recommended maximum relative humidity of 80%, and four out of the nine farms had ammonia concentrations greater than 40 ppm. Ammonia had negative correlations with ‘positive social behaviors’ and positive emotional states: content, enjoying, sociable, playful, lively, happy and it had positive correlations with negative emotional states: aimless, distressed. The concentration of carbon dioxide had negative correlations with positive emotional states; calm, sociable, playful, happy and it had a positive correlation with negative emotional state; aimless. Our results indicate that the control of the environment for growing pigs can help improve their welfare, particularly via good air quality (carbon dioxide, ammonia, hydrogen sulfide).

Evaluation of aqueous dimethyl trisulfide as an antidote to a highly lethal cyanide poisoning in a large swine model

BACKGROUND

Cyanide is a rapid acting, lethal, metabolic poison and remains a significant threat. Current FDA-approved antidotes are not amenable or efficient enough for a mass casualty incident.

OBJECTIVE

The objective of this study is to evaluate short and long-term efficacy of intramuscular aqueous dimethyl trisulfide (DMTS) on survival and clinical outcomes in a swine model of cyanide exposure.

METHODS

Anesthetized swine were instrumented and acclimated until breathing spontaneously. Potassium cyanide infusion was initiated and continued until 5 min after the onset of apnea. Subsequently, animals were treated with intramuscular DMTS (n = 11) or saline control (n = 10). Laboratory values and DMTS blood concentrations were assessed at various time points and physiological parameters were monitored continuously until the end of the experiment unless death occurred. A subset of animals treated with DMTS (n = 5) were survived for 7 days to evaluate muscle integrity by repeat biopsy and neurobehavioral outcomes.

RESULTS

Physiological parameters and time to apnea were similar in both groups at baseline and at time of treatment. Survival in the DMTS-treated group was 90% and 30% in saline controls (p = 0.0034). DMTS-treated animals returned to breathing at 12.0 ± 10.4 min (mean ± SD) compared to 22.9 ± 7.0 min (mean ± SD) in the 3 surviving controls. Blood collected prior to euthanasia showed improved blood lactate concentrations in the DMTS treatment group; 5.47 ± 2.65 mmol/L vs. 9.39 ± 4.51 mmol/L (mean ± SD) in controls (p = 0.0310). Low concentrations of DMTS were detected in the blood, gradually increasing over time with no elimination phase observed. There was no mortality, histological evidence of muscle trauma, or observed adverse neurobehavioral outcomes, in DMTS-treated animals survived to 7 days.

CONCLUSION

Intramuscular administration of aqueous DMTS improves survival following cyanide poisoning with no observed long-term effects on muscle integrity at the injection site or adverse neurobehavioral outcomes.

Application of a Protocol to Assess Camel Welfare: Scoring System of Collected Measures, Aggregated Assessment Indices, and Criteria to Classify a Pen

Simple Summary

During the last few decades, several protocols have been developed for assessing the on-farm welfare of several animal species. However, a protocol for camels has only recently been proposed. This study, for the first time, applied this assessment protocol and developed a model to compound overall welfare indices and classify pens according to their welfare level. The welfare measures were collected in 76 pens of a camel market in Qatar, scored, and then aggregated to obtain overall welfare indices. Thirst Index, Body Condition Score (BCS), disease and physical injuries, feeding and watering management, presence of a shelter, and cleanliness of bedding were the measures that strongly affected the classification of the pens. The model seemed to be able to identify the major welfare concerns of camels kept at the market and to suggest corrective actions. Further studies are needed to implement the proposed model, but it may be the first step towards the definition of welfare standards for camels.

Abstract

This study aimed to apply a protocol for assessing camel welfare, to develop a scoring system for the welfare measures, to produce overall assessment indices, and to classify the animal units (i.e., pens) according to their welfare level. A total of 105 measures were collected at Herd level from 76 pens at a market in Qatar. The pens held 528 camels, 132 of which were evaluated at a deeper level (i.e., Animal level). Out of the 105 measures, 71 were selected, scored, and aggregated to reach a Total Welfare Index (TWI) for each pen. The TWI ranged from 46.2 to 69.8. The Good Feeding index, including measures related to prolonged thirst and prolonged hunger, was the most critical (p < 0.001), while the Good Health index, including measures related to the absence of injuries, disease and pain, was the less problematic (p < 0.001). However, most of the pens were classified as “unsatisfactory” (61.8%) and none as “excellent”. Body Condition Score (BCS), Thirst Index, disease and physical injuries, presence of a shelter, and cleanliness of bedding were the measures which influenced the pens’ classification the most (p < 0.05). The proposed model seems useful in the identification of camel welfare issues. Further applications, as well as the involvement of many scientists and stakeholders, are needed to refine and validate the protocol and its indices.

Genetic diversity of MHC-B in 12 chicken populations in Korea revealed by single-nucleotide polymorphisms

This study used a single-nucleotide polymorphism (SNP) panel to characterise the diversity in the major histocompatibility complex B region (MHC-B) in 12 chicken populations in Korea. Samples were genotyped for 96 MHC-B SNPs using an Illumina GoldenGate genotyping assay. The MHC-B SNP haplotypes were predicted using 58 informative SNPs and a coalescence-based Bayesian algorithm implemented by the PHASE program and a manual curation process. In total, 117 haplotypes, including 24 shared and 93 unique haplotypes, were identified. The unique haplotype numbers ranged from 0 in Rhode Island Red to 32 in the Korean native commercial chicken population 2 ("Hanhyup-3ho"). Population and haplotype principal component analysis (PCA) indicated no clear population structure based on the MHC haplotypes. Three haplotype clusters (A, B, C) segregated in these populations highlighted the relationship between the haplotypes in each cluster. The sequences from two clusters (B and C) overlapped, whereas the sequences from the third cluster (A) were very different. Overall, native breeds had high genetic diversity in the MHC-B region compared with the commercial breeds. This highlights their immune capabilities and genetic potential for resistance to many different pathogens.

Nutrient digestibility, haemo-biochemical parameters and growth performance of an indigenous chicken strain fed canola meal-containing diets

Canola meal (CM) is a potential alternative dietary protein source for indigenous chickens but its utility may be limited by anti-nutrients such as fibre and phytochemical compounds. This study, therefore, explores the effects of replacing soy-based feedstuffs (SB) with graded levels of CM on apparent nutrient digestibility, growth performance and haemo-biochemical parameters in Potchefstroom koekoek (PK) cockerels. Five isonitrogenous and isoenergetic diets were formulated by replacing 0 (CM), 3.75 (CM1), 6.25 (CM2), 8.75 (CM3) and 17.5% (CM4) of SB with CM. One hundred and seventy-five cockerels (342.6 ± 15.2 g live weight, 5 weeks old) were evenly distributed into 25 replicate pens to which experimental diets were randomly allocated. Feed intake, apparent nutrient digestibility, weight gain, feed conversion ratio and protein efficiency ratio (PER) were determined. Blood was collected for serum and haematological analysis at 16 weeks of age. There was a significant quadratic trend [y = 2.56 (± 0.067) + 0.04 (± 0.019)x - 0.002 (± 0.0010)x²] for average weight gain from which an optimum canola inclusion level was calculated to be 7.8%. Neutrophils linearly increased (P < 0.05) with CM levels, but there were no significant linear and quadratic trends for serum biochemical components with the exception of total calcium and triglycerides, which decreased linearly in response to incremental levels of CM. However, feed intake, feed utilisation efficiency, growth performance and serum biochemistry parameters were not affected by experimental diets. Based on weight gain response, it was concluded that replacing soy-based dietary ingredients with CM in poultry diets up to 7.8% does not result in adverse effects on diet utilisation, growth performance and health status of PK cockerels.

Levofloxacin is phytotoxic and modifies the protein profile of lupin seedlings

The toxicity of levofloxacin to yellow lupin plants was evaluated in this study. Recommended indexes of plant (roots and shoots) growth were determined and new indexes were proposed which better characterise the phytotoxicity of levofloxacin. These were, in particular, the activity of antioxidative enzymes, the content of free radicals, as well as the root protein content and the root protein profile. The results showed that levofloxacin considerably affected EC₅₀, measured as the activity of catalase in roots, and leaves (1.05 and 0.069 mM, respectively). The activity of peroxidase in the roots and the dry weight of seedlings were the least sensitive parameters (EC₅₀ was 1.8 and 1.76 mM, respectively). Units of toxicity clearly showed that the activity of catalase is a better measure of toxicity for low concentrations of the drug, and it is a better index of plant physiological state than the morphological parameters of seedlings. Moreover, levofloxacin changed the location of free radicals and the protein profile in plants. The changes in location of reactive oxygen species in roots were an important symptom of the drug toxicity to lupin seedlings. Our results have shown that the toxicity of levofloxacin was manifested mainly by changes in the protein profile. The content of the glyceraldehyde-3-phosphate dehydrogenase, 14-3-3-like protein A, expansin-B3-like precursor, fructose-bisphosphate aldolase, lipoxygenase, nucleotide-binding subunit of vacuolar ATPase and pyruvate dehydrogenase were found to decrease. On the other hand, plant exposure to levofloxacin resulted in an increase in the content of enolase, protein LlR18A, class III chitinase, ascorbate peroxidase, aspartate aminotransferase, alcohol dehydrogenase 1, leghemoglobin reductase-like 17 and heat shock cognate protein 80-like.

Effects of relative humidity on animal health and welfare

Farm animals are sources of meat, milk and eggs for the humans, and animal health ensures the quality and security of these agricultural and sideline products. The animal raising conditions in livestock stations and poultry houses play vital roles in both animal health and production. One of the major factors affecting raising conditions, relative humidity, has not received much attention even though it is important for animal husbandry. In this review, we summarize the impacts of relative humidity on animal health and welfare to draw attention for its importance in the improvement of animal raising conditions in the future.

A Detrimental Role of Immunosuppressive Drug, Dexamethasone, During Clostridium difficile Infection in Association with a Gastrointestinal Microbial Shift

We investigated the increased risk of Clostridium difficile infection (CDI) caused by the combined use of antibiotics and an immunosuppressive drug in a mouse model. Our data showed that an approximate return to pretreatment conditions of gut microbiota occurred within days after cessation of the antibiotic treatment, whereas the recovery of gut microbiota was delayed with the combined treatment of antibiotics and dexamethasone, leading to an increased severity of CDI. An alteration of gut microbiota is a key player in CDI. Therefore, our data implied that immunosuppressive drugs can increase the risk of CDI through the delayed recovery of altered gut microbiota.

Effects of Forage:Concentrate Ratio on Growth Performance, Ruminal Fermentation and Blood Metabolites in Housing-feeding Yaks

The objective of this study was to determine the effect of forage: concentrate ratio (F:C) on growth performance, ruminal fermentation and blood metabolites of housing-feeding yaks. Thirty-two Maiwa male yaks (initial body weight = 207.99±3.31 kg) were randomly assigned to four dietary treatments (8 yaks per treatment). Experimental diets were: A, B, C, D which contained 70:30, 60:40, 50:50 and 40:60 F:C ratios, respectively. Dry matter intake and average daily gain in yaks fed the C and D diets were greater (p<0.05) than yaks fed the A and B diets. No differences were found in ruminal NH₃-N, total volatile fatty acids, acetate, butyrate, valerate, and isovalerate concentrations. The propionate concentration was increased (p<0.05) in the C and D groups compared with the A and B diets. In contrast, the acetate to propionate ratio was decreased and was lowest (p<0.05) in the C group relative to the A and B diets, but was similar with the D group. For blood metabolites, no differences were found in serum concentrations of urea-N, albumin, triglyceride, cholesterol, low density lipoprotein, alanine aminotransferase, and aspartate aminotransferase (p>0.05) among treatments. Treatment C had a higher concentration of total protein and high density lipoprotein (p<0.05) than A and B groups. In addition, there was a trend that the globulin concentration of A group was lower than other treatments (p = 0.079). Results from this study suggest that increasing the level of concentrate from 30% to 50% exerted a positive effect on growth performance, rumen fermentation and blood metabolites in yaks.