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Routine procedures carried out on piglets (i.e. castration, tail docking, teeth clipping, and ear notching) are considered painful. Unfortunately the efficacy of current pain mitigation modalities is poorly understood. The aim of this systematic review was to synthesize the existing primary scientific literature regarding the effectiveness of pain management interventions used for routine procedures on piglets. The review question was, 'In piglets under twenty-eight days old, undergoing castration, tail docking, teeth clipping, and/or methods of identification that involve cutting of the ear tissue, what is the effect of pain mitigation compared with no pain mitigation on behavioral and non-behavioral outcomes that indicate procedural pain and post-procedural pain?' A review protocol was designed a priori. Data sources used were Agricola (EBSCO), CAB Abstracts (Thomson Reuters), PubMed, Web of Science (Thomson Reuters), BIOSIS Previews (Thomson Reuters), and ProQuest Dissertations & Theses Full Text. No restrictions on year of publication or language were placed on the search. Eligible studies assessed an intervention designed to mitigate the pain of the procedures of interest and included a comparison group that did not receive an intervention. Eligible nonEnglish studies were translated using a translation service. Two reviewers independently screened titles and abstracts for relevance using pre-defined questions. Data were extracted from relevant articles onto pre-defined forms. From the 2203 retrieved citations forty publications, containing 52 studies met the eligibility criteria. In 40 studies, piglets underwent castration only. In seven studies, piglets underwent tail docking only. In one study, piglets underwent teeth clipping only, and in one study piglets underwent ear notching only. Three studies used multiple procedures. Thirty-two trial arms assessed general anesthesia protocols, 30 trial arms assessed local anesthetic protocols, and 28 trial arms assessed non-steroidal antiinflammatory drugs (NSAIDs) protocols. Forty-one trial arms were controls where piglets received either placebo or no treatment. Forty-five outcomes were extracted from the studies, however only the results from studies that assessed cortisol (six studies), b-endorphins (one study), vocalisations (nine studies), and pain-related behaviors (nine studies) are reported. Other outcomes were reported in only one or two studies. Confident decision making will likely be difficult based on this body of work because lack of comprehensive reporting precludes calculation of the magnitude of pain mitigation for most outcomes.

Piglets reared in swine production in the USA undergo painful procedures that include castration, tail docking, teeth clipping, and identification with ear notching or tagging. These procedures are usually performed without pain mitigation. The objective of this project was to develop recommendations for pain mitigation in 1-to 28-day-old piglets undergoing these procedures. The National Pork Board funded project to develop recommendations for pain mitigation in piglets. Recommendation development followed a defined multi-step process that included an evidence summary and estimates of the efficacies of interventions. The results of a systematic review of the interventions were reported in a companion paper. This manuscript describes the recommendation development process and the final recommendations. Recommendations were developed for three interventions (CO 2 /O 2 general anesthesia, non-steroidal anti-inflammatory drugs (NSAIDs), and lidocaine) for use during castration. The ability to make strong recommendations was limited by low-quality evidence and strong certainty about variation in stakeholder values and preferences. The panel strongly recommended against the use of a CO 2 /O 2 general anesthesia mixture, weakly recommended for the use of NSAIDs and weakly recommended against the use of lidocaine for pain mitigation during castration of 1-to 28-day-old piglets.

The authors would like to thank the Attorney General of Iowa (Smithfield Foods funds) for financial support of this research, and AB Vista, Ajinomoto Heartland, DSM Nutritional Products, and Hamlet Protein for in-kind support. Appreciation is also expressed to Dr. Christopher Tuggle for assistance with the genotype sequencing to test the genetic sensitivity of weaned pigs to F18 ETEC.

The objective of this study was to evaluate the effects of dietary xylanase (X) and a carbohydrase enzyme blend (EB: cellulase, β-glucanase, and xylanase) on nutrient digestibility, intestinal barrier integrity, inflammatory status, and growth performance in weaned piglets fed higher fiber diets. A total of 460 pigs (6.43 ± 0.06 kg BW; F25 × 6.0 Genetiporc) were blocked by initial BW and pens (n = 12 per treatment) were randomly assigned to 1 of 4 dietary treatments. The diets included a higher fiber unsupplemented control diet (CON) and the CON supplemented with 0.01% X, 0.01% EB, or both enzymes, arranged in a 2 × 2 factorial. The diets were based on corn, soybean meal, corn distillers dried grains with solubles (DDGS), and wheat middlings. Pigs had 7 d to adapt to the environment and consumed the same commercial diet. Pigs were fed the experimental diets for 28 d with free access to feed and water. Body weight and feed disappearance were recorded weekly. One pig with BW closest to the pen average from each pen was selected and moved to metabolism crates on day 16 and intragastric gavaged a solution of lactulose and mannitol on day 22 followed by 12-h urine collection. Feces were collected from day 23 to 25. Intestinal tissues and mucosal scrapings were collected on day 28. Data were analyzed using PROC MIXED of SAS (9.4). Xylanase, EB, and their interaction were fixed effects and block was a random effect. The EB, but not X, increased pig BW and improved ADG over 28 d (P < 0.05). Neither carbohydrase impacted ADFI, G:F, or apparent total tract digestibility (ATTD) of DM, GE, or CP. The EB improved ATTD of ADF (32.45 vs. 26.57%; P < 0.01), but had no effect on NDF. Unexpectedly, X reduced ATTD of NDF and ADF (P < 0.01). The EB reduced urinary lactulose:mannitol and increased ileal claudin-3 mRNA abundance (P < 0.05), indicating improved small intestinal barrier integrity. There was a X × EB interaction on ileal secretory immunoglobulin A (sIgA) concentration (P < 0.05); in the absence of X, EB decreased sIgA compared to CON, but this effect disappeared in the presence of X. The EB also reduced ileal IL-22 mRNA abundance (P < 0.05), probably indicating decreased immune activation. In conclusion, EB but not X enhanced growth rate of weaned pigs fed higher fiber diets, which may be partly explained by the improved small intestinal barrier integrity and reduced immune activation, rather than improvement in nutrient digestibility.

Post-weaning diarrhea caused by enterotoxigenic E. coli (ETEC) causes significant economic losses for pig producers. This study was to test the hypotheses that an ETEC challenge disrupts intestinal microbial homeostasis and the inclusion of dietary soluble (10% sugar beet pulp) or insoluble fiber (15% corn distillers dried grains with solubles) with or without exogenous carbohydrases will protect or restore the gut microbial homeostasis in weaned pigs. Sixty crossbred piglets (6.9 ± 0.1 kg) were blocked by body weight and randomly assigned to one of six treatments (n = 10), including a nonchallenged control (NC), ETEC F18-challenged positive control (PC), ETEC-challenged soluble fiber without (SF-) or with carbohydrases (SF+), and ETEC-challenged insoluble fiber without (IF-) or with carbohydrases (IF+). Pigs were housed individually and orally received either ETEC inoculum or PBS-sham inoculum on day 7 post-weaning. Intestinal contents were collected on day 14 or 15. The V4 region of the bacterial 16S rRNA was amplified and sequenced. High-quality reads (total 6,671,739) were selected and clustered into 3,330 OTUs. No differences were observed in α-diversity among treatments. The ileal microbiota in NC and PC had modest separation in the weighted PCoA plot; the microbial structures were slightly altered by SF+ and IF-compared with PC. The PC increased ileal Escherichia-Shigella (P < 0.01) and numerically decreased Lactobacillus compared to NC. Predicted functional pathways enriched in the ileal microbiota of PC pigs indicated enhanced activity of Gram-negative bacteria, in agreement with increased Escherichia-Shigella. The SF+ tended to decrease (P < 0.10) ileal Escherichia-Shigella compared to PC. Greater abundance of ileal Streptococcus, Turicibacter, and Roseburia and colonic Prevotella were observed in SF-and SF+ than PC (P < 0.05). Pigs fed IF + had greater Lactobacillus and Roseburia than PC pigs (P < 0.05). The ETEC challenge reduced total volatile fatty acid (VFA) compared with NC (P < 0.05). The SF+ tended to increase (P < 0.10) and SF-significantly

The objective of this experiment was to investigate the impact of an F18 enterotoxigenic Escherichia coli (ETEC) challenge on growth performance, aspects of intestinal function, and selected immune responses of piglets, as well as to evaluate potential protective effects of direct-fed microbial (DFM) blends. Seventy-two weaned piglets (6.4 ± 0.2 kg body weight [BW]; ~21 d of age) were assigned to one of four treatments: 1) NC: Nonchallenged (n = 10), 2) positive challenged control (PC): F18 ETEC-challenged (n = 10), 3) PC + DFM1 (n = 8; three strains of Bacillus amyloliquefaciens; 7.5 × 105 colony-forming units [cfu]/g), or 4) PC + DFM2 (n=8; 2 strains of B. amyloliquefaciens and one strain of Bacillus subtilis; 1.5 × 105 cfu/g). Feed intake and BW were recorded on day 0, 7, and 17. Pigs were sham-infected either with 6 mL phosphate-buffered saline or inoculated with 6 mL F18 ETEC (~1.9 × 109 cfu/mL) on day 7 (0 d postinoculation [dpi]). All ETEC-challenged pigs were confirmed to be genetically susceptible to F18. Pigs had ad libitum access to feed and water throughout the 17-d trial. Fecal scores were visually ranked and rectal temperatures were recorded daily. To evaluate ETEC shedding, fecal swabs were collected on dpi 0, 1, 2, 3, 5, 7, and 10. Blood samples were collected on dpi 0, 1, 2, 4, 7, and 10. Ileal tissues were collected at necropsy on dpi 10. All challenged treatments had lower final BW, decreased average daily gain (ADG), and average daily feed intake (ADFI) during the 10-d postchallenge period (P &lt; 0.01). The DFM2 treatment increased E. coli shedding on dpi 2 and decreased iton dpi 7 (P &lt; 0.05) compared with the PC. Rectal temperature decreased across all challenged treatments (P &lt; 0.01). Ileal mRNA abundance of occludin (OCLN) and zonula occludens-1 (ZO-1) decreased in PC and DFM1 compared with NC (P &lt; 0.05). Pigs fed DFM2 had intermediate ileal mRNA abundance of OCLN and increased ZO-1 mRNA compared with pigs in PC (P &lt; 0.05). Interleukin 8 (IL-8) increased in the plasma of PC and DFM2 on dpi 2 compared with NC (P &lt; 0.05). Mucosal IL-8 increased in PC compared with NC (P &lt; 0.05). All challenged treatments tended to have elevated tumor necrosis factor-α (TNF-α) mRNA abundance compared with NC (P &lt; 0.10). Challenged pigs had reduced secretory immunoglobulin A and villus height compared with NC pigs (P &lt; 0.05). The impact of an ETEC challenge on intestinal function and the immune system has been revealed, information critical to developing improved treatment regimes.

Background A randomized, masked, 2‐arm parallel trial was conducted to assess the efficacy of a Moraxella bovis (M. bovis) autogenous vaccine to prevent naturally occurring infectious bovine keratoconjunctivis (IBK) in beef calves. Hypothesis The null hypothesis was that treatment group was not associated with either risk of IBK or last observed weight. Animals The trial was conducted between May and November 2009 and 2010 on a university‐owned farm in Iowa. The vaccine contained 2 randomly selected M. bovis from IBK cases that occurred at the farm in 2008. Calves born between January and May 2009 and 2010 without visible corneal lesions were randomly allocated to receive vaccine (n = 191) or placebo (n = 178). Methods Two SC doses were administered 21–28 days apart. Allocation to treatment was concealed using bottles marked A or B. Staff observing the animals for IBK could not determine the treatment grouping. The herd met the “at‐risk” criteria (ie, >15% IBK in unvaccinated calves and M. bovis detection in IBK cases). Analysis was “per‐protocol”. Results The risk of IBK was 58/185 (31%) in vaccinated calves and 66/173 (38%) in unvaccinated calves (adjusted risk ratio = 0.78; 95% CI, 0.49–1.24). Average weight before sale did not differ between the vaccinated calves (196.6 kg, SD ± 39.9) and unvaccinated calves (198.1 kg, SD ± 42.7) (P value = .19). No adverse effects were noted. Conclusion and Clinical Importance Combination of the study results with previous studies suggests that autogenous M. bovis vaccines often are ineffective in controlling naturally occurring IBK.