Issues and gaps in international guidance and national regulatory systems affecting international live insect trade.

International trade in live insects involves the shipping of many different species, for various purposes, with a variety of handling requirements regulated by numerous authorities with varying objectives. The diversity of factors at play has both created and been subject to a complex regulatory landscape. A review of global production, shipping and use experiences from a range of perspectives has shown gaps and inconsistencies in international guidance and national implementation. Private carriers add another layer of uncertainty that is disproportionate to risks, resulting in variable practices and charges. Many benefits can come from international trade in insects, including pollinator services, control of pests and of disease vectors, and enhanced international scientific research and innovation. These benefits will be better achieved through a more evidence-based and efficient approach to regulating trade. This change in approach will in turn require an improved and widely accepted risk-management landscape for insect trade.

Le commerce international d'insectes vivants s'appuie sur les expéditions de nombreuses espèces différentes à diverses fins, assorties de multiples exigences relatives à la manutention régies par des autorités différentes poursuivant des objectifs distincts. La diversité des facteurs en jeu a rendu nécessaire la création d'un paysage normatif complexe, avec les contraintes qui lui sont associées. L'examen à l'échelle mondiale de la production, du transport et des expériences dans ce domaine depuis diverses perspectives a révélé un certain nombre de lacunes et d'incohérences au niveau des directives internationales et de leurs applications concrètes dans les pays. Les transporteurs privés ajoutent une dimension d'incertitude supplémentaire qui est disproportionnée par rapport aux risques, ce qui entraîne une forte variabilité des pratiques et des charges. Les échanges internationaux d'insectes génèrent nombre d'activités bénéfiques, parmi lesquelles les services de pollinisation, la lutte contre les ravageurs et les vecteurs de maladie, et l'accroissement de la recherche scientifique internationale et de l'innovation. Les objectifs attendus seront mieux atteints en adoptant une approche de la réglementation des échanges qui s'appuie davantage sur des éléments factuels et sur les gains d'efficacité. Ce changement méthodologique nécessitera à son tour la mise en place d'un cadre amélioré et plus largement accepté de la gestion des risques dans le domaine du commerce des insectes.

El comercio internacional de insectos vivos, que supone el transporte de muchas especies diferentes con fines diversos, se acompaña de requisitos de manipulación que dictan numerosas autoridades con todo tipo de objetivos. La diversidad de los factores que entran en juego ha sido a la vez causa y consecuencia de un complejo panorama reglamentario. Los autores, tras describir un estudio a escala mundial de la experiencia de producción, transporte y utilización de insectos vivos desde diferentes puntos de vista, exponen las carencias e incoherencias observadas en las directrices internacionales y su traslación a escala nacional. Los transportistas privados añaden otro factor de incertidumbre que tiene un peso desproporcionado en relación con el nivel de riesgo y se traduce en procedimientos y precios heterogéneos. El comercio internacional de insectos puede traer consigo muchos beneficios, en particular servicios de polinización, control de plagas y de vectores de enfermedad, y avances de la investigación e innovación científica a escala internacional. Pero obtener esos beneficios será más fácil si se aborda la regulación del comercio de manera más eficaz y científicamente fundamentada, operando un cambio de lógica que exigirá, a su vez, la aplicación al comercio de insectos de un régimen más sofisticado y ampliamente aceptado de gestión de los riesgos.

The World Organisation for Animal Health - current and potential roles in safe international trade of bees and other insects.

The World Organisation for Animal Health (WOAH, founded as OIE) is the recognised intergovernmental standard-setting organisation for animal health and welfare. The WOAH mandate is to support its members in the prevention of the spread of animal diseases of concern, as listed in the Terrestrial Animal Health Code (Terrestrial Code). Once a disease, infection or infestation is listed, national Veterinary Authorities have the obligation regularly to notify WOAH of the presence or absence of the listed disease. In regard to insects, the scope of the Terrestrial Code limits its recommendations to preserving the health of bees (species of the genus Apis, extended to the genus Bombus and to the stingless bees for one disease). However, it does not include standards to mitigate the potential animal health risks associated with the international trade of other insects. A description of the standard-setting process and a review of the history of the standards for bee health highlight the resources and requirements to expand the scope of the Terrestrial Code to include recommendations for animal health risk mitigation measures for the safety of international trade in insects. Any initiative to develop guidance on insect trade should include WOAH in its role as the sole global standard-setting organisation on animal health and welfare matters. This aligns with the WOAH commitment to a One Health approach.

L'Organisation mondiale de la santé animale (OMSA, fondée en tant qu'OIE) est l'organisation inter-gouvernementale reconnue pour l'élaboration de normes relatives à la santé et au bien-être des animaux. L'OMSA a pour mandat d'apporter un soutien à ses Membres afin de prévenir la propagation des maladies animales d'importance majeure listées dans le Code sanitaire pour les animaux terrestres (Code terrestre). Dès lors qu'une maladie, une infection ou une infestation figure sur cette liste, les Autorités vétérinaires ont l'obligation de notifier régulièrement à l'OMSA la présence ou l'absence de cette maladie sur leur territoire. S'agissant des insectes, le champ d'application du Code terrestre limite ses recommandations à la préservation de la santé des abeilles (espèces du genre Apis, avec l'inclusion du genre Bombus et des abeilles sans dard pour une maladie). Néanmoins, le Code terrestre ne contient pas de normes visant à atténuer les risques pour la santé animale associés aux échanges internationaux d'autres insectes. La description faite par les auteurs du processus d'élaboration des normes et leur aperçu rétrospectif de la mise au point des normes relatives à la santé des abeilles font ressortir les ressources et les conditions nécessaires pour élargir le champ d'application du Code terrestre afin d'y inclure des recommandations portant sur les mesures d'atténuation des risques pour la santé animale applicables à la sécurité sanitaire des échanges internationaux d'insectes. Toute initiative visant à fournir des orientations sur les échanges d'insectes devrait inclure l'OMSA dans son rôle d'unique organisation chargée de l'élaboration des normes internationales relatives à la santé animale et au bien-être des animaux. Cette exigence est en cohérence avec l'engagement de l'OMSA en faveur de l'approche Une seule santé.

La Organización Mundial de Sanidad Animal (OMSA, fundada como OIE) es la organización intergubernamental facultada para ejercer funciones normativas en materia de sanidad y bienestar de los animales. La OMSA tiene por mandato ayudar a sus miembros a prevenir la propagación de una serie de enfermedades animales de importancia, recogidas en el Código Sanitario para los Animales Terrestres (Código Terrestre) de la OMSA. La inclusión de una enfermedad, infección o infestación en la lista de la OMSA obliga a las autoridades veterinarias nacionales a dar cuenta periódicamente a la OMSA de la presencia o ausencia de esa patología en su territorio. Por lo que respecta a los insectos, en el Código Terrestre solo se formulan una serie de recomendaciones para proteger la salud de las abejas (categoría que corresponde a las especies del género Apis, extensible también al género Bombus y, en el caso de una enfermedad, a las abejas sin aguijón). El Código Terrestre, sin embargo, no contiene norma alguna destinada a mitigar los posibles riesgos zoosanitarios ligados al comercio internacional de otros insectos. Los autores describen el proceso normativo y repasan la historia de las normas relativas a la sanidad de las abejas, con lo que ponen de relieve los recursos y demás elementos necesarios para conferir mayor alcance al Código Terrestre incluyendo en él recomendaciones sobre medidas de mitigación del riesgo zoosanitario para un comercio seguro de insectos a escala internacional. Toda iniciativa encaminada a marcar pautas sobre el comercio de insectos debería incluir a la OMSA, única organización con potestad normativa mundial sobre temas de sanidad y bienestar de los animales, lo que además se encuadra en el compromiso de la OMSA con los planteamientos de «Una sola salud¼.

International live insect trade: a survey of stakeholders.

There are significant numbers of transboundary shipments of live insects for pollination, pest management, industrial processes, research and other uses, but data collection and analysis have proved difficult. The World Organisation for Animal Health and Collectif TIS (Technique de l'Insecte Stérile), a French think tank, carried out a stakeholder survey to understand the nature of the live insect trade and potential challenges to safety and efficiency. Target respondents had experience in the areas of biocontrol, sterile insect technique, entomological research and regulatory affairs. Although the survey was sent globally, the responses were unintentionally biased towards Europe, where interest is high, since this region is developing a comprehensive framework to promote the use of beneficial insects to replace pesticides. The survey also explored respondents' knowledge of several international agreements on the movement and risk management of beneficial or invasive insects. Knowledge of the various regulations was generally poor, and respondents highlighted a perceived lack of clarity regarding live insect shipments in the existing international regulations and guidelines. Almost two-thirds of participants reported reluctance by carriers to accept live insects for shipment, and three-quarters described occasional to systematic delays that resulted in a reduction of quality or viability. Some respondents reported that they instead hand-carry live insects, mostly in small quantities. Participants described being directly involved in trade covering 70 species of live insects and ticks transported among 37 countries, with volumes ranging from fewer than ten insects to over a million per shipment. Of these, 30% were potential vectors of pathogens to humans or animals, 42% were potential plant pest species (including some used for biocontrol), and 17% were classical biocontrol agents. The results of this survey begin to define the current scope, scale and issues for those involved in shipping live insects and ticks across political boundaries. The survey's aim is to persuade regulatory bodies and shipping operators to facilitate safety, efficiency and consistency in this underdeveloped sector.

Les insectes vivants font l'objet d'un nombre important d'expéditions transfrontalières à des fins de pollinisation, de gestion des nuisibles, d'utilisation dans des processus industriels et de recherche, parmi d'autres emplois ; or, la collecte et l'analyse de données sur le sujet se sont révélées difficiles. L'Organisation mondiale de la santé animale et le Collectif TIS (Technique de l'insecte stérile), groupe de réflexion français, ont mené une enquête auprès de parties prenantes afin de comprendre la nature du commerce international d'insectes vivants ainsi que les éventuels problèmes de sécurité et d'efficacité qui lui sont associés. Les répondants sont des acteurs expérimentés dans les domaines du contrôle biologique, de la technique de l'insecte stérile, de la recherche entomologique et des questions réglementaires. Si le questionnaire a été distribué dans toutes les régions du monde, les réponses ont toutefois présenté un biais involontaire privilégiant l'Europe, région où l'intérêt pour cette question est élevé compte tenu du cadre réglementaire qui y est actuellement mis en place pour promouvoir l'utilisation des insectes utiles en replacement des pesticides. L'enquête visait également à déterminer le niveau de connaissance des répondants sur les divers accords internationaux relatifs aux mouvements d'insectes utiles ou envahissants, ainsi que sur la gestion des risques en la matière. Il en ressort que les diverses réglementations sont généralement méconnues, les répondants mettant en avant leur perception d'un manque de clarté des réglementations et directives internationales applicables aux expéditions d'insectes vivants. Près des deux tiers des participants ont fait état des réticences des transporteurs à accepter des cargaisons d'insectes vivants et les trois quarts d'entre eux ont rapporté des retards occasionnels ou systématiques se traduisant par une perte de qualité ou de viabilité. Certains répondants ont déclaré qu'ils préféraient transporter eux-mêmes les insectes vivants, la plupart du temps en petites quantités. Les répondants ont décrit leur participation directe dans des échanges couvrant au total 70 espèces de tiques et d'insectes vivants transportés dans 37 pays, avec des volumes allant de moins de dix insectes à plus d'un million d'insectes par cargaison. Parmi les espèces transportées, 30 % étaient potentiellement vectrices d'agents pathogènes pour les humains ou les animaux, 42 % étaient des nuisibles potentiels pour les végétaux (y compris certaines espèces utilisées à des fins de lutte biologique) et 17 % étaient des agents classiques de la lutte biologique. Les résultats de cette enquête permettent d'esquisser la portée et l'échelle des expéditions transfrontalières d'insectes vivants et de tiques, ainsi que la teneur des problèmes rencontrés par ceux qui y prennent part. L'objectif de l'enquête est de convaincre les organismes chargés de la réglementation ainsi que les transporteurs internationaux de la nécessité d'apporter de meilleures conditions de sécurité et d'efficacité à ce secteur sous-développé et d'en assurer la cohérence.

Pese al importante número de envíos transfronterizos de insectos vivos que se realizan con fines de polinización, gestión de plagas, procesos industriales, investigación u otros usos, hasta ahora ha resultado difícil reunir y analizar datos al respecto. La Organización Mundial de Sanidad Animal y el grupo de reflexión francés Collectif TIS (Technique de l'Insecte Stérile) hicieron una encuesta entre las partes interesadas con el fin de conocer mejor las características del comercio de insectos vivos y los factores que pueden amenazar su seguridad y eficacia. La encuesta iba dirigida a personas con experiencia en materia de control biológico, uso de la técnica del insecto estéril, investigaciones entomológicas o aspectos reglamentarios. Aunque la encuesta fue distribuida por todo el mundo, las respuestas presentaban un involuntario sesgo «europeo¼ debido al gran interés que el tema suscita en Europa, donde se está elaborando un marco reglamentario para promover el uso de insectos beneficiosos en sustitución de los plaguicidas. La encuesta indagaba asimismo en el grado de conocimiento que tenían los participantes de varios acuerdos internacionales relativos al desplazamiento de insectos beneficiosos o invasores y a la gestión de los riesgos conexos. En términos generales, los encuestados conocían poco las diversas reglamentaciones y destacaban lo que a su juicio era falta de claridad de las vigentes normativas y directrices internacionales por lo que respecta a los cargamentos de insectos vivos. Casi dos tercios de los participantes afirmaron que los transportistas eran reacios a aceptar cargamentos de insectos vivos y tres cuartas partes refirieron demoras ocasionales o sistemáticas que mermaban la calidad o viabilidad de las remesas. Algunos dijeron haber optado a cambio por el transporte manual de insectos vivos, casi siempre en pequeñas cantidades. Los encuestados afirmaron tomar parte directamente en un comercio que mueve 70 especies de insectos o ácaros vivos por 37 países, en cantidades que van desde menos de diez insectos a más de un millón de ejemplares por envío. De esas especies, un 30% correspondía a posibles vectores de patógenos humanos o animales, un 42% a posibles plagas vegetales (algunas de ellas utilizadas con fines de control biológico) y un 17% a agentes clásicos de control biológico. Los resultados permiten empezar a acotar el alcance, la escala y la naturaleza de los problemas a que se enfrentan quienes intervienen en el envío transfronterizo de insectos y ácaros vivos. La encuesta tiene por objetivo convencer a organismos de reglamentación y transportistas de que procuren fomentar la seguridad, eficiencia y coherencia de este infradesarrollado sector.

Maternal antibiotic treatment affects offspring gastric sensing for umami taste and ghrelin regulation in the pig.

BACKGROUND: Scarce is knowledge on the process regulating the development of acid secretion, orexigenic signaling, and chemosensing in the stomach of young pigs. Changes of early microbial encounters by suckling pigs can interact with the gut maturation, by the induction of different molecular signaling. Our goal was to assess if the age of offspring and the maternal environment, influenced by sow antibiotic treatment peripartum, could affect gastric morphology and the expression of genes involved in the control of hydrochloric secretion, feed intake, taste, and inflammation in offspring stomach. METHODS: 84 pigs from sows fed a diet with amoxicillin (on -d10 to +d21 from farrowing, ANT) or without (CON) were sacrificed at d14, d21, d28 (weaning) or d42. Samples of oxyntic (OXY), pyloric (PY) and cardiac mucosae close to OXY were collected and parietal and enteroendocrine cells (EECs) were counted. Relative gene expression of a set of 11 key genes (ATP4A, SSTR2, GAST, GHRL, MBOAT4, PCSK1, GNAT1, TAS1R1, TAS1R3, IL8 and TNF) was assessed by qRT-PCR. In addition, 40 offspring obtained from the same ANT and CON sows were offered a normal or a fat-enriched diet for 4 weeks between 140 and 169 d of age, and then OXY and PY were sampled. RESULTS: The number of parietal and EECs increased with age (P < 0.001). ATP4A increased with age (within suckling, P = 0.043, post-weaning vs. suckling, P < 0.001), SSTR2 increased only after weaning (P < 0.001). In OXY, GHRL increased during suckling (P = 0.012), and post-weaning as a trend (P = 0.088). MBOAT4 tended to increase during suckling (P = 0.062). TAS1R1 increased from suckling to post-weaning period (P =0.001) and was lower in ANT offspring (P = 0.013). GNAT1 in PY was higher in ANT offspring (P = 0.041). Antibiotic treatment of sows peripartum increased expression of GHRL and MBOAT4 in OXY of growing-finishing offspring aged 5 months. CONCLUSIONS: Data show that sensing for umami taste and ghrelin regulation can be affected by maternal environment, but the development of acid secretion, orexigenic signaling and taste perception in the stomach are mostly developmentally controlled.

Knowledge and opinions of veterinary students in Italy toward animal welfare science and law.

Animal welfare (AW) is a growing concern worldwide and veterinary students are expected to demonstrate a high degree of professional interest in the welfare of animals. However, previous studies have highlighted gaps in the teaching of AW teaching in different countries, possibly impairing veterinary competency in the area. This survey aimed to assess the opinions of Italian veterinary students towards AW, as well as their knowledge on the issue. Questions were divided into different sections, investigating the definition of, and information on, AW, knowledge about AW legislation, and the level of tolerance towards AW in regard to the use of animals for different purposes. Results showed that behaviour was the most frequently used word to define AW. Italian students considered their own level of knowledge on AW as good, relying on their university training, websites and television. They requested more AW legislation, but when questioned on specifics of the current legislation, there was a general lack of knowledge. Although poultry, pigs and rabbits were considered the species experiencing the worst management conditions, the species that raised the most AW concerns were companion animals and cattle. Results from this investigation may allow the development of tailored actions aimed at appropriately implementing educational strategies, at national and international levels, to improve the role of future veterinarians as leaders in AW.

Effect of fasting and refeeding on expression of genes involved in the gastric nutrient sensing and orexigenic control of pigs.

Knowledge on orexigenic signals in the pig stomach is poor. Gastric amino acid sensing by taste receptor type 1 member 3 (T1R3) and calcium-sensing receptor (CASR), and active ghrelin release, controlled by preproghrelin, proprotein convertase (PC1/3) and ghrelin O-acyltransferase (GOAT) genes, may be affected by fasting or refeeding. Twelve pigs (12.0 kg LW) were adapted to a base diet and assigned to three individual feeding schedules: Control (C), fed twice a day; Fasting (F), fasted for 24 h; Refeeding (R), fasted for 24 h and refed before slaughtering. Gastrointestinal segments were collected for histology and molecular biology analyses. Total RNA isolated from oxyntic and pyloric mucosae was reverse transcribed, specific porcine primers were designed and transcript quantification was performed by real-time RT-PCR. F decreased villus height in duodenum (p < 0.01) and ileum (p < 0.05) vs. C and R. R increased oxyntic PC1/3 (p < 0.05) and tended to increase oxyntic preproghrelin (p = 0.06), and pyloric GOAT (p = 0.07) gene expression vs. C. PC1/3 gene expression was higher in pyloric mucosa. Ghrelin-positive cells numbers were not different between the two gastric mucosae. Gastrin expression tended to be higher in R than in C and F (p = 0.068 and p = 0.055). CASR was higher in pyloric than in oxyntic mucosa, and pyloric CASR expression tended to be higher in R than in C (p = 0.072). T1R1 was not affected by treatment. Our results indicate that the pool of genes involved in the secretion of active ghrelin is active both in oxyntic and pyloric mucosa of pig. Refeeding can significantly affect the expression of genes that control octanoyl-ghrelin production and partially the amino acid sensing by CASR gene, while the absence of effect of fasting on the expression of ghrelin-related genes needs further confirmations.

Effect of added dietary threonine on growth performance, health, immunity and gastrointestinal function of weaning pigs with differing genetic susceptibility to Escherichia coli infection and challenged with E. coli K88ac.

Threonine (Thr) is important for mucin and immunoglobulin production. We studied the effect of added dietary Thr on growth performance, health, immunity and gastrointestinal function of weaning pigs with differing genetic susceptibility to E. coli K88ac (ETEC) infection and challenged with ETEC. Forty-eight 24-day-old weaned pigs were divided into two groups by their ETEC susceptibility using mucin 4 (MUC4) gene as a marker (2 MUC4(-/-) , not-susceptible, and 2 MUC4(+/+) , susceptible, pigs per litter). Within genotype, pigs were fed two different diets: 8.5 (LThr) or 9.0 (HThr) g Thr/kg. Pigs were orally challenged on day 7 after weaning and slaughtered on day 12 or 13 after weaning. Before ETEC challenge, HThr pigs ate more (p < 0.05). The diet did not affect post-challenge growth, but HThr tended to increase post-challenge feed efficiency (p = 0.087) and overall growth (p = 0.087) and feed efficiency (p = 0.055). Before challenge, HThr pigs excreted less E. coli (p < 0.05), while after challenge, diet did not affect the number of days with diarrhoea and ETEC excretion. MUC4(+/+) pigs responded to the challenge with more diarrhoea, ETEC excretion and anti-K88 IgA in blood and jejunal secretion (p < 0.001). HThr pigs had a higher increase of anti-K88 IgA values in jejunal secretion (p = 0.089) and in blood (p = 0.089, in MUC4(+/+) pigs only). Thr did not affect total IgA and IgM values, morphometry of jejunum, goblet cells count in colon, total mucin from jejunum and colon, but varied jejunal goblet cells counts (p < 0.05). In the first two post-weaning weeks, 8.5 g Thr/kg diet may be not sufficient to optimize initial feed intake, overall feed efficiency and intestinal IgA secretion and to control the gut microbiota in the first post-weaning week, irrespective of the pig genetic susceptibility to ETEC infection.

Drivers for animal welfare policies in Europe.

The European region has been, and remains, a global leader in the development of animal welfare policies. The region has a great diversity of cultures and religions, different levels of socio-economic development, and varied legislation, policies and practices. Nevertheless, there are common drivers for animal welfare policy based on a history of animal welfare ethics and obligations to animal users and society in general. A unifying goal of countries in the region is to achieve sustainable compliance with the World Organisation for Animal Health (OIE) standards on animal health and welfare. Ethics isthe overarching driver, supported by the actions of governmental, inter-governmental and non-governmental activities, markets and trade, science and knowledge. Historically, organisations involved in promoting animal welfare have tended to act in isolation. For example, non-governmental organisations (NGOs) have run campaigns to influence retailers and the welfare policies of their farmer suppliers. Increasingly, different organisations with common or complementary goals are working together. For example, competent authorities, inter-governmental bodies and NGOs have combined their efforts to address dog population control across several countries in the region. Also, animal welfare is becoming integrated into the corporate social responsibility targets of private companies. Science and knowledge, as drivers and tools, are assisting with the harmonisation of welfare standards, e.g. by providing a common basis for measuring welfare impacts through animal-based measures and widespread sharing of this information. Current trends suggest that there will be greater collaboration among the organisations driving change, and increasing convergence of animal welfare strategies and welfare assessment tools. The result will be increased harmonisation of animal welfare standards throughout the region.

Feed supplemented with 3 different antibiotics improved food intake and decreased the activation of the humoral immune response in healthy weaned pigs but had differing effects on intestinal microbiota.

The aim of this study was to determine the effects of 3 antibiotics used for pulmonary pathologies added in the feed of weaned pigs on growth performance, commensal microbiota, and immune response. At weaning, a total of 72 pigs were randomly assigned by BW and litter to 1 of the following diets: control (typical weaning diet), control + 400 mg of tilmicosin/kg, control + 600 mg of amoxicillin/kg, and control + 300 mg of doxycycline/kg. Individually penned pigs were slaughtered after 3 wk (12 pigs/treatment) or 4 wk (6 pigs/treatment). During the fourth week, all pigs received the control diet to test the residual effect of the antimicrobial supplementation. The antibiotic supplementation increased growth and feed intake during the first week (P < 0.01) and over the first 3 wk combined (P < 0.05). Gain-to-feed ratio tended to improve during the first week (P = 0.076) by the antibiotics compared with the control. Among the antibiotic treatments, no difference was observed in ADG and feed intake, which were also unchanged by the diet in the fourth week. The fecal enterobacteria counts were increased by amoxicillin on d 14 and 21 (P < 0.05 and 0.01, respectively) and were decreased by tilmicosin (P < 0.001) compared with the control. Amoxicillin decreased lactic acid bacteria (P < 0.01) counts compared with the control. The antibiotic supplementation tended to decrease total bacteria variability in the jejunum (Shannon index, P = 0.091) compared with the control. The antibiotic treatment decreased the mean total serum IgM concentration (P = 0.016) after 3 wk and did not change the mucosal histomorphometry of the small intestine. For tilmicosin, the observed positive action on piglet performance and feed intake can originate by the decreased costs of immune activation determined by the action on intestinal microbiota. For amoxicillin and doxycycline, the observation on intestinal and fecal microbiota seems to be not sufficient to explain their growth-promoting effect.

Effect of high oral doses of nitrate on salivary recirculation of nitrates and nitrites and on bacterial diversity in the saliva of young pigs.

Ingested nitrate is absorbed in the small intestine, recirculated into the saliva and reduced to nitrite by oral bacteria. In pigs receiving a moderate dietary addition of nitrate, the recirculation into the saliva is modest, so we aimed to assess the effect of higher nitrate doses to find out how the animal reacts to this new situation and to evaluate if a higher nitrate level could enhance the nitrate reduction process, improving the nitrite production Trial 1. Six piglets received 100 g of a commercial diet with 2.45% KNO(3) . In relation to baseline values, nitrate in blood serum and saliva increased 15 times, and declined after 6 h vs. 2 h. Salivary nitrite increased seven times after the addition and declined after 6 h vs. 2 h. Trial 2. Six piglets were fed a diet with or without 1.22% KNO(3) for 2 weeks. Salivary nitrate and nitrite increased with the addition of KNO3: nitrate increased from d0 to the end of the trial, nitrite increased 15 times after 1 week, but decreased after 2 weeks to 4.5-fold the control. After 2 weeks, nitrate reduced Shan diversity index of salivary microbiota. The present results indicate that the long exposure to high quantities of nitrates impairs the oral reduction of nitrate to nitrite and engenders a reduction of the mouth's microbiota diversity.