Expert opinion on the identification, risk assessment, and mitigation of microorganisms and parasites relevant to xenotransplantation products from pigs.

Xenotransplantation has the potential to address shortages of organs available for clinical transplantation, but concerns exist regarding potential risks posed by porcine microorganisms and parasites (MP) to the health of human recipients. In this study, a risk-based framework was developed, and expert opinion was elicited to evaluate porcine MP based on swine exposure and risk to human health. Experts identified 255 MP to include in the risk assessment. These were rated by experts for five criteria regarding potential swine exposure in the USA and human health risks. MP were subsequently categorized into three risk mitigation groups according to pre-defined rules: disqualifying porcine MP (due to their pathogenic potential, n = 130); non-disqualifying porcine MP (still relevant to consider for biosecurity or monitoring efforts, n = 40); and alert/watch list (not reported in the USA or MP not in swine, n = 85). Most disqualifying (n = 126) and non-disqualifying (n = 36) porcine MP can effectively be eliminated with high biosecurity programs. This approach supports surveillance and risk mitigation strategies for porcine MP in swine produced for xenotransplantation, such as documentation of freedom from porcine MP, or use of porcine MP screening, monitoring, or elimination options. To the authors' knowledge, this is the first effort to comprehensively identify all relevant porcine MP systematically and transparently evaluate the risk of infection of both donor animals and immunosuppressed human recipients, and the potential health impacts for immunosuppressed human recipients from infected xenotransplantation products from pigs.

Prevalence of serum immunoglobulin E against cross-reactive carbohydrate determinants in allergic and nonallergic horses, and its impact on polysensitisation in serum allergen tests.

BACKGROUND: The existence of antibodies against cross-reactive carbohydrate determinants (CCDs) has been studied extensively in humans, and more recently, in dogs and cats. These antibodies can reduce the specificity of in vitro serum allergen tests. OBJECTIVES: To investigate the prevalence of anti-CCD immunoglobulin (Ig)E in both allergic and nonallergic horses as well as evaluate its potential impact on serum allergen testing. ANIMALS: Twenty-one allergic and 21 nonallergic horses. METHODS AND MATERIALS: Sera were analysed for anti-CCD IgE utilising a commercial CHO enzyme-linked immunosorbent assay (ELISA). An allergen specific Fc-ε receptor ELISA then was performed to evaluate polysensitisation, both with and without the addition of a proprietary anti-CCD blocking solution. RESULTS: Antibodies against CCD were detected in 30 of 42 horses. There was no statistically significant difference (p = 0.18) between the allergic and healthy groups in regard to anti-CCD prevalence. Horses with anti-CCD IgE exhibited more polysensitisation on serum allergen tests than horses without anti-CCD IgE in all allergen groups except mites. Polysensitisation was statistically significant at the 95% confidence interval for grasses (p <0.03), weeds (p = 0.02) and stinging insects (p = 0.0005). This was found to be true across both study groups. Inhibition with an anti-CCD blocking solution resulted in a 43% average reduction in polysensitisation. CONCLUSION AND CLINICAL IMPORTANCE: The prevalence of anti-CCD IgE of horses in this study coincides with the prevalence detected in pollen-sensitised people. Horses with anti-CCD IgE exhibited more positive reactions on serum allergen tests. By minimising potential artifactual polysensitisation, inclusion of an anti-CCD blocker may facilitate identification of allergen-specific IgE.

Contexte - L'existence d'anticorps contre les déterminants glucidiques à réaction croisée (CCD) a été largement étudiée chez l'homme et, plus récemment, chez le chien et le chat. Ces anticorps peuvent réduire la spécificité des tests d'allergènes sériques in vitro. Objectifs - Étudier la prévalence de l'immunoglobuline anti-CCD (Ig)E chez les chevaux allergiques et non allergiques et évaluer son impact potentiel sur les tests d'allergènes sériques. Animaux - Vingt et un chevaux allergiques et 21 chevaux non allergiques. Matériels et méthodes - Les sera ont été analysés pour les IgE anti-CCD en utilisant un dosage immuno-enzymatique CHO commercial (ELISA). Un ELISA du récepteur Fc-ε spécifique à l'allergène a ensuite été réalisé pour évaluer la polysensibilisation, avec et sans l'ajout d'une solution exclusive de blocage anti-CCD. Résultats - Des anticorps anti-CCD ont été détectés chez 30 des 42 chevaux. Il n'y avait pas de différence statistiquement significative (P = 0,18) entre les groupes allergiques et sains en ce qui concerne la prévalence anti-CCD. Les chevaux avec des IgE anti-CCD ont montré plus de polysensibilisation aux tests d'allergènes sériques que les chevaux sans IgE anti-CCD dans tous les groupes d'allergènes à l'exception des acariens. La polysensibilisation était statistiquement significative à l'intervalle de confiance de 95 % pour les graminées (P < 0,03), les herbacées (P = 0,02) et les insectes piqueurs (P = 0,0005). Cela s'est avéré vrai dans les deux groupes d'étude. L'inhibition avec une solution de blocage anti-CCD a entraîné une réduction moyenne de 43 % de la polysensibilisation. Conclusion et importance clinique - La prévalence des IgE anti-CCD des chevaux dans cette étude coïncide avec la prévalence détectée chez les personnes sensibilisées au pollen. Les chevaux avec des IgE anti-CCD ont présenté des réactions plus positives aux tests d'allergènes sériques. En minimisant la polysensibilisation artificielle potentielle, l'inclusion d'un bloqueur anti-CCD peut faciliter l'identification des IgE spécifiques de l'allergène.

Introducción- la existencia de anticuerpos contra los determinantes de carbohidratos de reacción cruzada (CCD) se ha estudiado ampliamente en humanos y, más recientemente, en perros y gatos. Estos anticuerpos pueden reducir la especificidad de las pruebas de alérgenos séricos in vitro. Objetivos - Investigar la prevalencia de inmunoglobulina (Ig)E anti-CCD tanto en caballos alérgicos como no alérgicos, así como evaluar su impacto potencial en las pruebas de alérgenos séricos. Animales- veintiún caballos alérgicos y 21 no alérgicos. Métodos y materiales- los sueros se analizaron para detectar IgE anti-CCD utilizando un ensayo comercial inmunoabsorbente ligado a enzimas (ELISA) para CHO. A continuación, se realizó un ELISA del receptor Fc-ε específico del alérgeno para evaluar la polisensibilización, con y sin la adición de una solución de bloqueo anti-CCD patentada. Resultados- se detectaron anticuerpos contra CCD en 30 de 42 caballos. No hubo diferencia estadísticamente significativa (P = 0,18) entre los grupos alérgicos y sanos con respecto a la prevalencia de anti-CCD. Los caballos con IgE anti-CCD exhibieron más polisensibilización en las pruebas de alérgenos séricos que los caballos sin IgE anti-CCD en todos los grupos de alérgenos excepto los ácaros. La polisensibilización fue estadísticamente significativa en el intervalo de confianza del 95 % para pastos (P < 0,03), malas hierbas (P = 0,02) e insectos picadores (P = 0,0005). Se encontró que esto fue similar en ambos grupos de estudio. La inhibición con una solución de bloqueo anti-CCD resultó en una reducción promedio del 43 % en la polisensibilización. Conclusión e importancia clínica - La prevalencia de IgE anti-CCD de los caballos en este estudio coincide con la prevalencia detectada en personas sensibilizadas al polen. Los caballos con IgE anti-CCD exhibieron más reacciones positivas en las pruebas de alérgenos en suero. La inclusión de un bloqueador anti-CCD puede facilitar la identificación de IgE específica de alérgeno al minimizar la posible polisensibilización artificial.

Contexto - A existência de anticorpos contra determinantes de carboidratos de reação cruzada (CCDs) tem sido estudada extensivamente em humanos, e, mas recentemente, em cães e gatos. Estes anticorpos podem reduzir a especificidade de testes alérgicos sorológicos in vitro. Objetivos - Investigar a prevalência de imunoglobulina (Ig)E tanto em cavalos alérgicos quanto em cavalos não alérgicos e avaliar o seu potencial impacto no teste alérgico sorológico. Animais - Vinte e um cavalos alérgicos e 21 não alérgicos. Métodos e materiais - O soro foi testado para IgE anti-CCD utilizando um ensaio imunoenzimático CHO comercial (ELISA). Um ELISA alérgeno-específico para receptor Fc-ε foi realizado para avaliar polissensibilização, com e sem a adição de uma solução de bloqueio anti-CCD. Resultados - Anticorpos anti-CCD foram encontrados em 30 de 42 cavalos. Não houve diferença estatística significativa (P = 0,18) entre os grupos alérgico e saudável quanto à prevalência de anti-CCD. Cavalos com IgE anti-CCD exibiram mais polissensibilização no teste alérgico sorológico que cavalos sem IgE anti-CCD em todos os grupos alergênicos, exceto ácaros. Polissensibilização foi estatisticamente significativa em um intervalo de confiança de 95% para gramíneas (P < 0,03), herbáceas (P = 0,02) e insetos que picam (P = 0,0005). Isto foi verdadeiro para os dois grupos estudados. Inibição com uma solução bloqueadora de anti-CCD resultou em uma redução média de 43% na polissensibilização. Conclusão e importância clínica - A prevalência de IgE anti-CCD em cavalos nesse estudo coincide com a prevalência detectada em pessoas sensibilizadas a pólen. Equinos com IgE anti-CCD apresentaram mais reações positivas nos testes alérgicos sorológicos. Minimizando uma potencial polissensibilização a partir da utilização de um bloqueador de anti-CCD pode facilitar a identificação de IgE alérgeno-específica.

A bidirectional relationship between anxiety, depression and gastrointestinal symptoms in Parkinson's disease.

INTRODUCTION: Anxiety, depression and gastrointestinal (GI) symptoms are common non-motor symptoms in Parkinson's disease (PD). Past studies provide evidence of a disrupted microbiome-gut-brain axis in PD, which is associated with certain motor and non-motor symptoms in PD. Additionally, there is evidence of a bidirectional association between mental health and gut health among individuals with GI disorders. The current study examined the bidirectional association between GI symptoms and anxiety/depression among individuals newly diagnosed with PD. METHODS: We conducted a secondary data analysis of the Parkinson's Progression Markers Initiative. This included 487 individuals newly diagnosed with PD and followed for up to 5 years. Participants completed questionnaires of anxiety, depression and GI symptoms (Scales for Outcomes in Parkinson's Disease Autonomic; SCOPA-AUT) at each annual visit. Multilevel models examined the bidirectional-lagged relationship between GI symptoms and anxiety/depression. RESULTS: Models provided evidence for a bidirectional relationship between GI symptoms and anxiety/depression. Specifically, more severe GI symptoms predicted more severe anxious/depressive symptoms within the same year and at the following year. There was also evidence of the inverse directionality, meaning that more severe anxiety/depression predicted more severe GI symptoms concurrently and in the following year. DISCUSSION: Findings provide preliminary evidence for a cyclical relationship among gut health and mental health in PD. Future studies are needed to examine if the microbiome-gut-brain axis plays a mechanistic role.

Direct Measurement of Veterinary Student Learning Outcomes for the NAVMEC Professional Competencies in a Multi-User Virtual Learning Environment.

Education in veterinary medicine, as in other allied health care-health science professions and academia in general, has been subject to the public call for accountability for the quality of its student learning outcomes. A principal stakeholder in veterinary medicine is the American Veterinary Medical Association-Council on Education (AVMA-COE). AVMA-COE has adopted program accreditation standards requiring veterinary colleges to provide evidence that they are measuring and assessing the clinical competency of students before graduation and again shortly after graduation. Schools and colleges are required to develop relevant measures to validate scientific knowledge, skills, and values aligned with North American Veterinary Medical Education Consortium (NAVMEC) core competencies. Beginning in May 2012, the College of Veterinary Medicine and Biomedical Sciences at Texas A&M University modified the professional veterinary medical curriculum by including a required clinical rotation centered on veterinary emergency preparedness and response. A distinguishing major component of the instructional design of the clinical rotation includes Second Life, a commercially obtained computer-generated multi-user virtual simulation learning environment. The virtual reality situations require high-volume, mass-casualty medical triage decision making. The interpersonal communications and interactivity among students, faculty, and third-party actors enable faculty and instructor observers and simulation facilitators to evaluate students actively engaged in critical thinking and complex problem solving while demonstrating skill in the NAVMEC professional competencies. The Second Life virtual simulation has been adopted as a primary tool for direct measurement of student learning objectives outcomes achieved in this clinical rotation and is being implemented in other clinical teaching platforms.

Effects of adding liquid lactose or molasses to pelleted swine diets on pellet quality and pig performance.

Two experiments were conducted to evaluate the effects of including liquid lactose (LL) and molasses (M) in swine diets on pellet quality and pig performance. In experiment 1, a total of 194 nursery pigs (DNA 241 × 600, initially 6.7 ± 0.4 kg at 27 d of age) were used in a 33-d experiment evaluating the effects of LL (SweetLac 63; Westway Feed Products, Tomball, TX) or cane molasses on nursery pig performance and pellet quality. Pelleted experimental diets were fed from d 0 to 21, and a common pelleted diet fed from d 21 to 33. Dietary treatments consisted of a control diet containing 19.1% total sugars from whey powder and whey permeate and experimental diets with a percentage of whey permeate replaced by either 5% or 10% LL or 9.4% cane molasses (5 LL, 10 LL, and 9.4 M, respectively). Hot pellet temperature and production rate decreased (P < 0.05) from the control to 9.4 M treatments with 5 LL and 10 LL having intermediate effects. Pellet durability index (PDI) increased (P < 0.05) in 5 LL, 10 LL, and 9.4 M, respectively. From d 0 to 7, pigs fed the 10 LL and 9.4 M treatment had the best G:F followed by the control and 5 LL treatments. From d 0 to 21, ADFI had a marginally significant improvement (P < 0.10) in pigs fed up to 10 LL in the diet. Fecal consistency scores at d 7 were also firmer (P < 0.05) in pigs fed 9.4 M compared with pigs fed the control or 5 LL treatments with pigs fed the 10 LL treatment being intermediate. There was no evidence for differences in fecal consistency scores for d 14. In experiment 2, a total of 289 finishing pigs (DNA 241 × 600; initially 53.5 ± 0.5 kg BW) were used in a 53-d experiment evaluating the effects of LL on pellet quality and finishing pig performance. Experimental diets were fed in pelleted form from d 0 to 53 divided into three phases. Dietary treatments were a corn-soybean meal control diet with 0%, 2.5%, 5%, and 7.5% LL added in the place of corn. PDI improved (linear, P < 0.01) with increasing inclusion of LL. There were no differences in ADG, ADFI, final BW, or carcass characteristics. Pigs fed diets with increasing levels of LL tended to have improved (quadratic, P = 0.070) G:F.

Effects of aquatic conditioning on cartilage and bone metabolism in young horses.

While beneficial in rehabilitation, aquatic exercise effects on cartilage and bone metabolism in young, healthy horses has not been well described. Therefore, 30 Quarter Horse yearlings (343 ± 28 kg; 496 ± 12 d of age) were stratified by age, body weight (BW), and sex and randomly assigned to 1 of 3 treatments for 140-d to evaluate effects of aquatic, dry, or no exercise on bone and cartilage metabolism in young horses transitioning to an advanced workload. Treatments included nonexercise control (CON; n = 10), dry treadmill (DRY; n = 10), or aquatic treadmill exercise (H2O; n = 10; water: 60% wither height, WH). Horses were housed individually (3.6 × 3.6 m) from 0600 to 1800 hours, allowed turnout (74 × 70 m) from 1800 to 0600 hours, and fed to meet or exceed requirements. During phase I (days 0 to 112), DRY and H2O walked on treadmills 30 min/d, 5 d/wk. Phase II (days 113 to 140) transitioned to an advanced workload 5 d/wk. Every 14-d, WH, hip height (HH), and BW were recorded. Left third metacarpal radiographs on days 0, 112, and 140 were analyzed for radiographic bone aluminum equivalence (RBAE). Every 28-d, serum samples were analyzed for osteocalcin and C-telopeptide crosslaps of type I collagen (CTX-1), and synovial fluid samples were analyzed for prostaglandin E2, collagenase cleavage neopeptide (C2C), collagenase of type I and type II collagen, and carboxypeptide of type II collagen using ELISAs. All data were analyzed using PROC MIXED of SAS, including random effect of horse within treatment, and repeated effect of day. Baseline treatment differences were accounted for using a covariate. There were treatment × day interactions (P < 0.01) where OC and CTX-1 remained consistent in both exercise groups while inconsistently increasing in CON. There were no treatment differences (P > 0.30) in RBAE, BW, or HH, but all increased over time (P < 0.01). There were no treatment × day interactions of synovial inflammation or markers of cartilage metabolism; however, there was an effect of day for each marker (P<0.03). Changes in biomarkers of cartilage turnover in horses exercised at the walk, whether dry or aquatic, could not be distinguished from horses with access to turnout alone. This study indicates that early forced exercise supports consistent bone metabolism necessary for uniform growth and bone development, and that there are no negative effects of buoyancy on cartilage metabolism in yearlings transitioned from aquatic exercise to a 28-d advanced workload.

Skeletal response to whole body vibration and dietary calcium and phosphorus in growing pigs.

The quality and strength of the skeleton is regulated by mechanical loading and adequate mineral intake of calcium (Ca) and phosphorus (P). Whole body vibration (WBV) has been shown to elicit adaptive responses in the skeleton, such as increased bone mass and strength. This experiment was designed to determine the effects of WBV and dietary Ca and P on bone microarchitecture and turnover. A total of 26 growing pigs were utilized in a 60-d experiment. Pigs were randomly assigned within group to a 2 × 2 factorial design with dietary Ca and P concentration (low and adequate) as well as WBV. The adequate diet was formulated to meet all nutritional needs according to the NRC recommendations for growing pigs. Low Ca, P diets had 0.16% lower Ca and 0.13% lower P than the adequate diet. Pigs receiving WBV were vibrated 30 min/d, 3 d/wk at a magnitude of 1 to 2 mm and a frequency of 50 Hz. On days 0, 30, and 60, digital radiographs were taken to determine bone mineral content by radiographic bone aluminum equivalency (RBAE) and serum was collected to measure biochemical markers of bone formation (osteocalcin, OC) and bone resorption (carboxy-terminal collagen crosslinks, CTX-I). At day 60, pigs were euthanized and the left third metacarpal bone was excised for detailed analysis by microcomputed tomography (microCT) to measure trabecular microarchitecture and cortical bone geometry. Maximum RBAE values for the medial or lateral cortices were not affected (P > 0.05) by WBV. Pigs fed adequate Ca and P tended (P = 0.10) to have increased RBAE max values for the medial and lateral cortices. WBV pigs had significantly decreased serum CTX-1 concentrations (P = 0.044), whereas animals fed a low Ca and P diet had increased (P < 0.05) OC concentrations. In bone, WBV pigs showed a significantly lower trabecular number (P = 0.002) and increased trabecular separation (P = 0.003), whereas cortical bone parameters were not significantly altered by WBV or diet (P > 0.05). In summary, this study confirmed the normal physiological responses of the skeleton to a low Ca, P diet. Interestingly, although the WBV protocol utilized in this study did not elicit any significant osteogenic response, decreases in CTX-1 in response to WBV may have been an early local adaptive bone response. We interpret these data to suggest that the frequency and amplitude of WBV was likely sufficient to elicit a bone remodeling response, but the duration of the study may not have captured the full extent of an entire bone remodeling cycle.

Novel association of Psychrobacter and Pseudomonas with malodour in bloodhound dogs, and the effects of a topical product composed of essential oils and plant-derived essential fatty acids in a randomized, blinded, placebo-controlled study.

BACKGROUND: The pathogenesis and treatment of cutaneous malodour in dogs have not been investigated previously. Staphylococcus and Corynebacterium spp. are associated with human axillary malodour. HYPOTHESIS: Staphylococcus and Corynebacterium spp. are associated with cutaneous malodour in dogs, and treatment with a topical essential oil-based product will improve malodour and reduce the abundance of odour-causing bacteria. ANIMALS: Twenty seven bloodhound dogs from a south Texas boarding facility were enrolled in this study. METHODS AND MATERIALS: Skin swabs were taken from the axilla and dorsum of 27 dogs at initiation of the study. Mean malodour scores were used to assign dogs to control or malodour groups. The malodourous dogs were randomly assigned to a treatment or placebo group, received four weekly topical applications of the spot-on or placebo, and samples were recollected. Next-generation sequencing (NGS) and real-time quantitative PCR (qPCR) were performed on all swabs. RESULTS: Psychrobacter and Pseudomonas spp. were significantly more abundant (P < 0.001, P = 0.006; respectively), and overall bacterial diversity was reduced (P = 0.0384) on the skin of malodourous dogs. Staphylococcus and Corynebacterium spp. were not associated with malodour. The topical essential oil-based product significantly (P = 0.0078) improved malodour in the treatment group and shifted their bacterial community structure. CONCLUSIONS AND CLINICAL IMPORTANCE: A novel association of bacterial genera with malodour in bloodhound dogs, identified by NGS, highlights future targets for odour control. The topical treatment significantly reduced malodour. The interaction between the topical treatment and cutaneous microbiota should be further investigated and may be useful in other dermatological conditions involving microbiota.

An experimental model for calcium carbonate urolithiasis in goats.

BACKGROUND: Calcium carbonate is a common urolith type in small ruminants with no high-yield experimental model to evaluate animal susceptibility or preventative measure response. HYPOTHESIS: That novel plastic winged implants would allow accumulation and quantification of calcium carbonate calculus formation in goats on a high-calcium diet and identify individual variation between goats in the mass of calculi produced. ANIMALS: Eight nonpregnant 3- and 4-year-old Boer-cross does, weighing 22.3-39.5 kg, determined to be healthy based on physical examination, were used in these experiments. METHODS: Prospective cohort study for in vivo experimental model development. Implants were placed into the urinary bladder lumen in 8 goats over 2 evaluation periods. The alfalfa-based ration had a total ration Ca : P of 3.29 and 3.84 : 1, respectively. Urine was collected at 0, 28, 56, and 84 days in the 1st experiment; blood and urine at those timepoints in the 2nd experiment. For each evaluation period, the implants were removed 84 days after implantation and weighed. Accumulated calculi mass was calculated and compared between goats and was analyzed for composition. RESULTS: Implant retention was 100% and 86% in the 2 studies. All goats with retained implants accumulated calcium carbonate at a mean implant gain per day across studies ranging from 0.44 to 57.45 mg. Two goats accumulated (0.44-7.65 mg/day and 33.64 & 57.45 mg/day) significantly more urolith material than the cohort across both studies (P = .047). No routine analytes on blood or urine were found to be explanatory for the difference observed. CONCLUSIONS AND CLINICAL IMPORTANCE: These findings form a basis for implant and diet selection for use in future studies of urolithiasis development and for studies regarding individual susceptibility to urolithiasis.

Epidemiology and Molecular Typing of Trypanosoma cruzi in Naturally-Infected Hound Dogs and Associated Triatomine Vectors in Texas, USA.

BACKGROUND: Trypanosoma cruzi is the etiologic agent of Chagas disease throughout the Americas. Few population-level studies have examined the epidemiology of canine infection and strain types of T. cruzi that infect canines in the USA. We conducted a cross-sectional study of T. cruzi infection in working hound dogs in south central Texas, including analysis of triatomine vectors collected within kennel environments. METHODOLOGY/PRINCIPLE FINDINGS: Paired IFA and Chagas Stat-Pak serological testing showed an overall seroprevalence of 57.6% (n = 85), with significant variation across kennels. Dog age had a marginally significant effect on seropositivity, with one year of age increase associated with a 19.6% increase in odds of being seropositive (odds ratio 95% CI 0.996-1.435; p = 0.055). PCR analyses of blood revealed 17.4% of dogs harbored parasite DNA in their blood, including both seronegative and seropositive dogs. Molecular screening of organs from opportunistically sampled seropositive dogs revealed parasite DNA in heart, uterus, and mammary tissues. Strain-typing showed parasite discrete typing units (DTU) TcI and TcIV present in dog samples, including a co-occurrence of both DTUs in two individual dogs. Bloodmeal analysis of Triatoma gerstaeckeri and Triatoma sanguisuga insects collected from the kennels revealed exclusively dog DNA. Vector infection with T. cruzi was 80.6% (n = 36), in which T. gerstaeckeri disproportionately harbored TcI (p = 0.045) and T. sanguisuga disproportionately harbored TcIV (p = 0.029). Tracing infection status across dog litters showed some seropositive offspring of seronegative dams, suggesting infection of pups from local triatomine vectors rather than congenital transmission. CONCLUSIONS/SIGNIFICANCE: Canine kennels are high-risk environments for T. cruzi transmission, in which dogs likely serve as the predominant parasite reservoir. Disease and death of working dogs from Chagas disease is associated with unmeasured yet undoubtedly significant financial consequences because working dogs are highly trained and highly valued.

Analytic validation of commercially available immunoassays for the measurement of serum cobalamin and folate concentrations in pigs.

BACKGROUND: Cobalamin (vitamin B12 ) and folate (vitamin B9 ) are important for the amino acid metabolism and nucleic acid synthesis. Immunoassays for the measurement of both vitamins in serum are routinely used in people, cats, and dogs, serving as indicators for clinical disorders including cobalamin and/or folate deficiency, small intestinal dysbiosis, or inadequate dietary supply of these vitamins. The analysis of these analytes may also be clinically useful in pigs. OBJECTIVE: The purpose of this study was to analytically validate immunoassays for the measurement of cobalamin and folate concentrations in porcine serum, and to determine serum cobalamin and folate concentrations in healthy newborn pigs pre- and postweaning. METHODS: Assay validation for both vitamins included the determination of linearity, accuracy, and intra- and inter-assay variability using serum samples from 10 pigs. Also, serum cobalamin and folate concentrations were compared in piglets between pre- and postweaning. RESULTS: For both vitamins, observed-to-expected ratios for linearity and accuracy were 93.2 ± 14.3% and 100.3 ± 8.1% (mean ± standard deviation), respectively. Intra- and inter-assay coefficients of variation for serum were ≤ 8.7% and ≤12.5%, respectively. Significantly higher serum cobalamin and lower folate concentrations were observed in piglets at the time of weaning than at postweaning (P < .0061; P < .0001, respectively). CONCLUSIONS: Both immunoassays are linear, accurate, precise, and reproducible for measurement of porcine serum cobalamin and folate concentrations. Piglets differing in age by only 12 days had significantly different serum cobalamin and folate concentrations. The implications of differing serum cobalamin and folate concentrations in pigs at different stages of life should be further investigated.