A comparison of 4 iron supplementation protocols to protect suckling piglets from anemia.

Pigs are routinely supplemented with iron during the suckling period to prevent anemia, but recent studies have shown that despite iron treatment many fast-growing pigs are iron deficient at weaning. The objective of this study was to determine if oral iron supplementation provided free-choice from a week of age until weaning could prevent iron deficiency. Results showed that the industry standard treatment of a single iron injection at 4 days of age did not always prevent iron deficiency at weaning, indicating the need to provide additional iron to fast-growing suckling pigs either orally or by a second injection. It appears that providing piglets daily access to iron-enriched peat moss or injecting a second 200-mg dose of iron intramuscularly are both effective in meeting the piglets iron requirements during the suckling period.

Comparaison de quatre protocoles de supplémentation en fer afin de protéger les porcelets nonsevrés d'anémie. Les porcs sont supplémentés de routine avec du fer durant la période d'allaitement afin de prévenir l'anémie, mais des études récentes ont démontré que malgré le traitement avec du fer plusieurs porcs à croissance rapide sont déficients en fer au moment du sevrage. L'objectif de la présente étude était de déterminer si une supplémentation orale en fer fournie au choix à partir d'une semaine d'âge jusqu'au moment du sevrage pourrait prévenir une déficience en fer. Les résultats ont démontré que le traitement standard de l'industrie d'une seule injection de fer à 4 jours d'âge ne prévenait pas toujours une déficience en fer au moment du sevrage, indiquant ainsi la nécessité de fournir du fer supplémentaire aux porcs non-sevrés à croissance rapide soit oralement ou par une seconde injection. Il semblerait que fournir aux porcelets un accès quotidien à de la mousse de tourbe enrichie de fer ou injecter par voie intramusculaire une deuxième dose de 200 mg de fer sont tous deux efficaces pour subvenir aux besoins en fer des porcelets durant la période d'allaitement.(Traduit par Dr Serge Messier).

The relationship between hemoglobin levels at weaning and growth performance and antibody response in nursery pigs.

The objectives of this study were to determine whether weaned pigs with low hemoglobin (Hb) concentrations grow more slowly and produce poorer antibody response to vaccination compared to pigs with normal Hb concentrations, and to study the association between high levels of zinc oxide in feed and continued anemia in pigs during the nursery phase. At weaning, pigs were classified as anemic (< 90 g/L of Hb), iron deficient (90 to 110 g/L Hb), or normal (> 110 g/L Hb). Pigs were vaccinated twice against Mycoplasma hyopneumoniae and antibody response was measured 3 weeks after the last vaccination. Two trials were performed with diets containing 150 mg/kg of zinc oxide and a third trial was conducted with pigs fed a diet containing 3000 mg/kg of zinc oxide for 2 weeks post-weaning. Hemoglobin status didn't impact growth rate or antibody response to vaccination. High zinc levels in the feed did not alter the pattern of Hb concentrations in pigs post-weaning.

Relation entre les niveaux d'hémoglobine au sevrage et les performances de croissance et la réponse en anticorps chez des porcs en pouponnière. Les objectifs de la présente étude étaient de déterminer si les porcs sevrés avec de faibles concentrations en hémoglobine (Hb) avaient une croissance plus lente et produisaient moins d'anticorps en réponse à une vaccination comparativement à des porcs avec une concentration normale de Hb, et d'étudier l'association entre des niveaux élevés d'oxyde de zinc dans la moulée et une anémie continue chez les porcs durant la période en pouponnière. Au sevrage les porcs furent classés comme anémiques (< 90 g/L de Hb), déficients en fer (90 à 110 g/L de Hb) ou normaux (> 110 g/L de Hb). Les porcs furent vaccinés deux fois contre Mycoplasma hyopneumoniae et la réponse en anticorps mesurée 3 semaines après la dernière vaccination. Deux essais ont été effectués avec des diètes contenant 150 mg/kg d'oxyde de zinc et un troisième essai mené avec des porcs nourris avec une diète contenant 3000 mg/kg d'oxyde de zinc pendant 2 semaines après le sevrage. Le statu en hémoglobine n'avait pas d'impact sur le taux de croissance ou la réponse en anticorps à la suite de la vaccination. Des niveaux élevés de zinc dans la moulée n'ont pas altéré le patron des concentrations de Hb chez les porcs en post-sevrage.(Traduit par Dr Serge Messier).

Erratum: Rodrigues, L.; Amezcua, R.; Cassar, G.; O'Sullivan, T.; Friendship, R. Comparison of Single, Fixed-Time Artificial Insemination in Gilts Using Two Different Protocols to Synchronize Ovulation. Animals 2020, 10, 306.

The authors wish to make the following corrections to their paper [...].

Comparison of Single, Fixed-Time Artificial Insemination in Gilts Using Two Different Protocols to Synchronize Ovulation.

In order to efficiently have a consistent supply of service-ready gilts available to incorporate into each batch of breeding sows, it is necessary to manipulate the timing of estrus and possibly the timing of ovulation of gilts. Estrus can be synchronized by the withdrawal of altrenogest after at least 14 days of treatment. It is possible that protocols developed to induce ovulation, and therefore allow fixed-time artificial insemination (FTAI), can improve the predictability of gilt breeding. This study investigated the effect of two FTAI protocols in gilts on reproductive performance and timing of farrowing and piglet weaning weight compared to gilts bred based on signs of estrus after cessation of altrenogest. Puberty was induced in gilts, followed by treatment with altrenogest. Following altrenogest withdrawal, 180 gilts were assigned to one of three treatment groups. Group 1 gilts (LUT, n = 62) were treated with 600 IU equine chorionic gonadotropin 24 h after altrenogest withdrawal and 5 mg porcine luteinizing hormone (pLH) 80 h later, followed by a single FTAI 36 h after pLH. Group 2 gilts (TRI, n= 61) received 2 mL of a gonadotropin-releasing hormone agonist, triptorelin acetate, intravaginally 6 d after altrenogest withdrawal and were bred by a single FTAI 24 h later. Group 3 gilts (CON, n = 57) were observed for estrus and bred twice by AI, 24 h apart. LUT and TRI gilts farrowed closer together (2.4 ± 1.6 and 2.9 ± 1.2 d(days), respectively) compared to CON gilts (4.5 ± 3.3 d). Piglets in LUT were 80 g (p < 0.001) heavier and piglets in TRI were 64 g (p < 0.05) heavier at weaning than CON piglets, when controlling for birth weight. Results indicate that FTAI might be useful as a means of minimizing the time from the first to the last gilt farrowing in a breeding batch of gilts. However, modifications of the protocols may be required to ensure optimum farrowing rates and litter size.

Comparison of single, fixed-time artificial insemination in weaned sows using 2 different protocols to synchronize ovulation.

The present study evaluated 2 fixed-time artificial insemination (FTAI) techniques in sows in 2 herds. At weaning, sows were assigned to 1 of 3 treatment groups: Group 1 received intramuscular injections of 600 IU of equine chorionic gonadotropin followed 3 days later by 5 mg of porcine luteinizing hormone; Group 2 received a 200-µg intravaginal dose of triptorelin acetate 4 days post-weaning; and Group 3 were heat checked daily and double-mated when observed in heat. Groups 1 and 2 were bred once at a fixed-time independent of estrous behavior. Time of ovulation was monitored by ultrasound in a subset of sows from each group. Both FTAI techniques resulted in sows farrowing within short intervals, leading to the weaning of pigs that tended to be older and heavier compared with controls. The use of FTAI, however, was associated with a trend to reduced reproductive performance compared with controls in 1 herd.

Comparaison d'une insémination artificielle unique à temps déterminé chez des truies sevrées en utilisant deux protocoles différents pour synchroniser l'ovulation. La présente étude a évalué deux techniques d'insémination artificielle à temps déterminé (FTIA) chez des truies dans deux troupeaux. Au sevrage, les truies étaient assignées à un des trois groupes de traitement : Groupe 1 recevait par injection intramusculaire 600 UI de gonadotrophine chorionique équine suivi 3 jours plus tard de 5 mg d'hormone lutéinisante porcine; le Groupe 2 recevait par voie intravaginale une dose de 200 µg d'acétate de triptorelin 4 jours post-sevrage; et pour le Groupe 3 les chaleurs étaient vérifiées quotidiennement et il y avait double saillie lorsque les truies étaient observées en chaleur. Les truies des Groupe 1 et 2 furent saillies une fois à un temps déterminé indépendamment du comportement oestral. Le moment de l'ovulation était surveillé par échographie dans un sous-groupe de truies de chacun des groupes. Les deux techniques de FTAI ont résulté en des truies dont la mise-bas est survenue dans des intervalles rapprochés, entrainant le sevrage de porcelets qui avaient tendance à être plus âgés et plus lourds comparativement aux témoins. Toutefois, dans un des troupeaux l'utilisation de FTIA était associée avec une tendance à une diminution des performances de reproduction comparativement aux témoins.(Traduit par Dr Serge Messier).

Combining Fixed-Time Insemination and Improved Catheter Design in an Effort to Improve Swine Reproduction Efficiency.

Conventional practice is to breed sows by artificial insemination (AI) at least twice using approximately three billion sperm per insemination upon estrus at standing heat. This research explored the use of combined technologies, including fixed-time insemination (FTAI) and an alternative catheter design that reportedly reduces semen backflow, in order to reduce the number of inseminations and the semen dosage and maintain reproductive efficiency. The FTAI technique used in this study was to inject I.M. 600 IU equine chorionic gonadotropin (eCG) at weaning and 5 mg porcine luteinizing hormone (pLH) to stimulate ovulation 80 h later, followed by a single insemination 36 h after the pLH injection. The two catheters used in this study were a conventional foam-tipped insemination catheter and a Gedis catheter. The Gedis catheter is designed to be completely inserted into the vagina. The semen is enclosed along the length of the rod and held in place by a gel cap that melts when inserted into the cervix. Sows were assigned to the following treatments: Group 1 (n = 135), bred twice with a conventional catheter and a standard semen dose of approximately three billion sperm in 80 mL; Group 2 (n = 123), FTAI with conventional catheter and a standard semen dose; Group 3 (n = 127), FTAI with Gedis catheter and a standard semen dose; Group 4 (n = 126), FTAI with Gedis catheter and a reduced semen dose with one billion sperm. The farrowing rates were 81.6%, 77.7%, 74.0%, and 62.7% for Groups 1 to 4, respectively. The likelihood of farrowing was lower for Group 3 and Group 4 compared to Group 1 (odds ratio (OR) = 0.57; p = 0.08 and OR = 0.35; p = 0.001, respectively). Likewise, litter size of Group 3 and Group 4 was smaller than Group 1 (p = 0.006 and p = 0.04, respectively). Overall, the combination of Gedis catheter and FTAI resulted in decreased reproductive performance that outweighed the value of using less semen.

An attempted intervention to solve a problem of lightweight pigs at weaning.

The presence of a high proportion of lightweight pigs (< 4.5 kg) at weaning was identified as a problem on a 600-sow farrowing operation. An intervention strategy involving special care pens where underweight pigs were fed milk-replacer and transitioned to a commercial grain-based starter diet was evaluated and found to be of limited benefit.

Tentative d'intervention pour résoudre un problème de porcs à faible poids au sevrage. La présence d'une proportion élevée de porcs à faible poids (< 4,5 kg) au sevrage a été identifiée comme un problème dans une exploitation de mise bas de 600 truies. Une stratégie d'intervention comportant des cages de soins spéciaux, où les porcs à faible poids étaient nourris de lait de remplacement puis effectuaient la transition à une diète de départ commerciale à base de grains, a été évaluée et il a été constaté qu'elle avait des bienfaits limités.(Traduit par Isabelle Vallières).

Evaluation of the effect of umbilical hernias on play behaviors in growing pigs.

Umbilical hernias (UH) are common in pigs and are an animal welfare concern. This study used an assessment of play behavior to evaluate the welfare of pigs with UH. Twenty-one grower pigs with UH and 17 without hernias (WUH) were assigned to 16 playing groups (PG) of 2 or 3 pigs (with at least 1 UH pig per PG). The time each animal was engaged in any of the defined playing behaviors for locomotor/social or toy play behaviors was recorded. Mixed Poisson or negative binomial and linear models were used to determine the effect of UH and day of session, accounting for the cluster of pigs within groups, on the frequency of each play behavior, and playing times. Pigs with UH had the same frequency of most play behaviors and playing times as pigs without hernias. There was no indication that the presence of UH-affected play behavior or performance in pigs.

Évaluation de l'effet des hernies ombilicales sur les comportements de jeu chez les porcs en croissance. Les hernies ombilicales (HO) sont communes chez les porcs et elles représentent une préoccupation liée au bien-être animal. Cette étude a utilisé une évaluation du comportement de jeu afin d'évaluer le bien-être des porcs ayant une HO. Vingt-et-un porcs en croissance ayant une HO et 17 sans hernies (SHO) ont été assignés à 16 groupes de jeu (GJ) de 2 ou 3 porcs (avec au moins 1 porc HO par GJ). Le temps consacré par chaque animal pour participer à l'un des comportements de jeu définis pour les comportements de jeu de locomotion/social ou de jouet a été consigné. Des modèles mixtes de Poisson ou binomiaux et linéaires négatifs ont été utilisés pour déterminer l'effet de HO et le jour de la séance, en tenant compte des regroupements de porcs au sein des groupes, de la fréquence de chaque comportement de jeu et des moments de jeu. Les porcs avec une HO avait la même fréquence pour la plupart des comportements de jeu et des moments de jeu que les porcs SHO. Il n'y avait aucune indication que la présence d'une HO affectait le comportement de jeu ou la performance des porcs.(Traduit par Isabelle Vallières).

Infrared thermography to evaluate lameness in pregnant sows.

Early detection of lameness in sows is important to reduce losses and improve animal welfare. Mild-to-moderate lameness is difficult to diagnose in sows. Infrared thermography (IRT) was evaluated as a method of detecting signs of inflammation in the lower limbs as an aid in lameness detection.

Thermographie infrarouge afin d'évaluer la boiterie chez des truies gravides. La détection précoce de la boiterie chez les truies est importante pour réduire les pertes et améliorer le bien-être animal. Une boiterie de légère à modérée est difficile à diagnostiquer chez les truies. La thermographie infrarouge (TI) a été évaluée comme méthode pour détecter des signes d'inflammation dans les membres inférieurs et comme aide à la détection de la boiterie.(Traduit par Isabelle Vallières).

Preoperative ketoprofen administration to piglets undergoing castration does not affect subsequent growth performance.

The purpose of this study was to determine if treatment of pigs with ketoprofen (3 mg/kg body weight) before castration at 7 days of age would affect subsequent growth during the suckling period. Piglets from 301 litters were treated with ketoprofen or a placebo and weighed at castration and at weaning. There was no difference in growth rate between the 2 groups of pigs.

L'administration préopératoire de kétoprofène aux porcelets subissant une castration n'affecte pas la performance de croissance subséquente. Cette étude avait pour but de déterminer si le traitement des porcs avec le kétoprofène (3 mg/kg poids corporel) avant la castration à l'âge de 7 jours affecterait la croissance subséquente durant la période d'allaitement. Les porcelets provenant de 301 portées ont été traités à l'aide du kétoprofène ou d'un placébo et pesé à la castration et au sevrage. Il n'y avait aucune différence au niveau du taux de croissance entre les 2 groupes de porcs.(Traduit par Isabelle Vallières).

Describing antimicrobial use and reported treatment efficacy in Ontario swine using the Ontario Swine Veterinary-based Surveillance program.

BACKGROUND: The objective of this work was to retrospectively assess records received through the Ontario Swine Veterinary-based Surveillance program July 2007 - July 2009 to describe and assess relationships between reported treatment failure, antimicrobial use, diagnosis and body system affected. RESULTS: Antimicrobial use occurred in 676 records, 80.4% of all records recording treatment (840). The most commonly used antimicrobials were penicillin (34.9%), tetracyclines (10.7%) and ceftiofur (7.8%), and the use of multiple antimicrobials occurred in 141/676 records (20.9%). A multi-level logistic regression model was built to describe the probability of reported treatment failure. The odds of reported treatment failure were significantly reduced if the record indicated that the gastro-intestinal (GI) system was affected, as compared to all other body systems (p < 0.05). In contrast, the odds of reported treatment failure increased by 1.98 times if two antimicrobials were used as compared to one antimicrobial (p = 0.009) and by 6.52 times if three or more antimicrobials were used as compared to one antimicrobial (p = 0.005). No significant increase in reported treatment failure was seen between the use of two antimicrobials and three or more antimicrobials. No other antimicrobials were significantly associated with reported treatment failure after controlling for body system and the number of antimicrobials used. CONCLUSIONS: Failure of antimicrobial treatment is more likely to occur in non-GI conditions, as compared to GI conditions and the use of multiple antimicrobial products is also associated with an increased probability of antimicrobial treatment failure. The authors suggest that a more preventative approach to herd health should be taken in order to reduce antimicrobial inputs on-farm, including improved immunity via vaccination, management and biosecurity strategies. Furthermore, improved immunity may be viewed as a form of antimicrobial stewardship to the industry by reducing required antimicrobial inputs and consequently, reduced selection pressure for AMR.

Comparison of disease trends in the Ontario swine population using active practitioner-based surveillance and passive laboratory-based surveillance (2007-2009).

A concern about emerging swine diseases led to a pilot study to determine the feasibility of an active surveillance system referred to as the Ontario Swine Veterinary-based Surveillance System (OSVS). The OSVS recorded the incidence of various syndromes and investigated potential outbreaks. However, validation of the disease patterns observed was needed. The objective of this study was to compare the disease patterns observed in the OSVS system with submission data obtained from a regional diagnostic laboratory - the Animal Health Laboratory (AHL). Higher rates of submission were reported to the OSVS compared with AHL records. However, OSVS and AHL data captured similar trends of disease. The OSVS data captured potential outbreaks that were not reflected in the laboratory data. Validation of active and passive syndromic surveillance data is necessary, and efforts should be made to integrate these types of data sources.

Comparaison des tendances des maladies chez la population porcine de l'Ontario à l'aide d'une surveillance active effectuée par les praticiens et d'une surveillance passive basée sur les laboratoires (2007­2009). Des inquiétudes à propos de l'émergence de maladies porcines ont donné lieu à une étude pilote pour déterminer la faisabilité d'un système de surveillance active appelé système de surveillance des vétérinaires porcins de l'Ontario (Ontario swine veterinary-based surveillance system [OSVS]). L'OSVS a enregistré l'incidence de divers syndromes et a fait enquête sur les flambées potentielles. Cependant, la validation des tendances observées pour les maladies était requise. Cette étude avait pour objectif de comparer les tendances des maladies observées dans le système OSVS avec les données soumises obtenues d'un laboratoire de diagnostic régional ­ l'Animal Health Laboratory (AHL). Des taux de soumission supérieurs ont été signalés pour l'OSVS comparativement aux dossiers de l'AHL. Cependant, les données de l'OSVS et de l'AHL ont reflété des tendances semblables pour les maladies. Les données de l'OSVS reflétaient des flambées potentielles qui n'étaient pas signalées dans les données de laboratoire. La validation des données de surveillance syndromique active et passive sont nécessaires et des efforts devraient être déployés pour intégrer ces types de sources de données.(Traduit par Isabelle Vallières).

Patterns of condemnation rates in swine from a federally inspected abattoir in relation to disease outbreak information in Ontario (2005-2007).

Strong correlations between clinical signs on farms and the presence of lesions at slaughter have been reported. The objective of this study was to determine if changes in condemnation rates provide a data source for surveillance of disease outbreaks in pigs. The data were obtained from 1 abattoir in Ontario (2005-2007). The epidemiological relevance of the results was based on an outbreak of porcine circovirus associated disease (PCVAD) in Ontario in 2005. The total condemnations and condemnations due to arthritis and pneumonia patterns reflected the field infection of PCVAD in 2005 followed by the widespread use of porcine circovirus type 2 (PCV-2) vaccine in 2007. In contrast, increased rates of nephritis and enteritis suggested areas for enhanced surveillance for unexplained changes in disease patterns not identified through traditional passive surveillance. Further studies looking at the benefits of using abattoir data should compare condemnation patterns with multiple sources of swine health data.

The zoonotic potential of Mycobacterium avium spp. paratuberculosis: a systematic review.

BACKGROUND: The zoonotic potential of Mycobacterium avium ssp. paratuberculosis (MAP) has been debated for almost a century because of similarities between Johne's Disease (JD) in cattle and Crohn's disease (CD) in humans. Our objective was to evaluate scientific literature investigating the potential association between these two diseases (MAP and CD) and the presence of MAP in retail milk or dairy products using a qualitative systematic review. METHOD: The search strategy included 19 bibliographic databases, 8 conference proceedings, reference lists of 15 articles and contacting 28 topic-related scientists. Two independent reviewers performed relevance screening, quality assessment and data extraction stages of the review. RESULTS: Seventy-five articles were included. Among 60 case-control studies that investigated the association between MAP and CD, 37 were of acceptable quality. Twenty-three studies reported significant positive associations, 23 reported non-significant associations, and 14 did not detect MAP in any sample. Different laboratory tests, test protocols, types of samples and source populations were used in these studies resulting in large variability among studies. Seven studies investigated the association between CD and JD, two challenge trials reported contradictory results, one cross-sectional study did not support the association, and four descriptive studies suggested that isolated MAP is often closely related to cattle isolates. MAP detection in raw and pasteurized milk was reported in several studies. CONCLUSIONS: Evidence for the zoonotic potential of MAP is not strong, but should not be ignored. Interdisciplinary collaboration among medical, veterinary and other public health officials may contribute to a better understanding of the potential routes of human exposure to MAP.

An investigation of the presence of Escherichia coli O149:K91:F4 on pig farms in southern Ontario and the use of antimicrobials and risk factors associated with the presence of this serogroup.

Prevalence, causative factors, treatment, and preventative measures for O149:K91:F4 Escherichia coli infection of postweaning pigs was determined by using a cross-sectional study including 70 farms in Ontario. Surveys were distributed and samples cultured bacteriologically, resulting in 30% of farms testing positive to E. coli 0149:K91:F4. Possible causative factors, such as housing or nutrition, were not significantly different between positive and negative farms. Use of injectable antibiotics (P = 0.05) and zinc oxide (P = 0.003) was higher on E. coli O149:K91:K88 (F4)-positive farms. A higher level of biosecurity and the presence of other diseases may be associated with an increased risk of isolating E. coli O149:K91:F4 from weanling pigs.

Presentation of postweaning Escherichia coli diarrhea in southern Ontario, prevalence of hemolytic E. coli serogroups involved, and their antimicrobial resistance patterns.

Post-weaning Escherichia coli diarrhea (PWECD) in Ontario was investigated using a case-control study involving 50 Ontario nurseries. The clinical signs and the impact on productive parameters were determined by means of a producer survey. The hemolytic E. coli serogroups involved in PWECD (O149:K91:K88) were examined in this study. Based on a polymerase chain reaction test, the hemolytic E. coli from 82% of the case herds were positive for 3 enterotoxins (STa, STb, and LT), those from 12% of the case herds were positive for STb and LT only, and those from one herd (6%) were positive for 3 enterotoxins, as well as for verotoxin and F18 pili. The E. coli involved in disease were resistant to multiple antibiotics. Case farms commonly used a wide variety of antibiotics either in the feed or water, or as injectable drugs. The most common antibiotic used to treat PWECD on the study farms was apramycin, but evidence of resistance to this antibiotic was noted. The PWECD problem was commonly seen within a week of weaning but onset of diarrhea was reported as late as the grower-finisher stage. Growth rate was poorer in case herds and mortality was higher than in control herds, demonstrating that PWECD is an economically important disease in Ontario.