Increased Dietary Trp, Thr, and Met Supplementation Improves Performance, Health, and Protein Metabolism of Weaned Piglets under Mixed Management and Poor Housing Conditions

A sanitary challenge was carried out to induce suboptimal herd health while investigating the effect of amino acids supplementation on piglet responses. Weaned piglets of high sanitary status (6.33 ± 0.91 kg of BW) were distributed in a 2 × 2 factorial arrangement into two similar facilities with contrasting sanitary conditions and two different diets. Our results suggest that increased Trp, Thr, and Met dietary supplementation could support the immune systems of piglets under a sanitary challenge. In this manner, AA+ supplementation improved the performance and metabolism of piglets under mixed management and poor sanitary conditions. No major temporal microbiome changes were associated with differences in performance regardless of sanitary conditions or diets. Since piglets often become mixed in multiple-site production systems and facility hygiene is also often neglected, this study suggests that increased Trp, Thr, and Met (AA+) dietary supplementation could contribute to mitigating the side effects of these harmful risk factors in modern pig farms

Efeito de fontes de selênio no desempenho, retenção de selênio e variáveis fisiológicas em frangos de corte

Given its participation in physiological processes such as antioxidant defense systems and thyroid hormone secretion, selenium (Se) has received attention in poultry nutrition and supplementation of organic trace mineral in practical broiler feeds has been defended due to its bioavailability, which is beneficial on environmental grounds, as well because the results on response variables of interest in animal production. A dose-response assay was conducted to evaluate the growth performance, tissue mineralization, retention, and physiological responses of growing broilers fed diets containing different levels and sources of selenium. A total of 500 10-d-old male Cobb 500 broiler chicks were randomly assigned to 10 treatments with 10 replicates and five birds per replicate. Treatments were obtained from a 2×5 factorial arrangement where 2 sources of Se (sodium selenite [SS] and selenium yeast [SY]) were supplemented in semi-purified diets at 0, 0.08, 0.16, 0.24 and 0.32 mg Se/kg feed. Chicks fed SY diets had body weight (BW), and average daily gain (ADG) optimized at 0.133 and 0.130 mg Se/kg, respectively. Both Se sources linearly increased (P<0.05) the glutathione peroxidase (GSH-Px) activity in chick blood but higher values were observed in SS fed chicks (P<0.05). Both Se sources influenced the thyroid hormones serum concentration (P<0.05). Chicks fed SY exhibited greater retention of Se in the feathers (P<0.05). Organic Se as SY showed to be more bioavailable than SS. SY supplementation resulted in lower liver Se concentration as Se supplementation increased (P<0.05). Based on performance traits, the supplemental level of organic Se as SY to support the proper growth of broiler chicks is 0.133 mg Se/kg. Keywords: Glutathione peroxidase. Organic trace minerals. Selenium balance. Selenium yeast. Tissue mineralization.Diante da sua participação em processos fisiológicos como defesa antioxidante e hormônios tireoidianos, o selênio (Se) tem recebido atenção na nutrição de frangos de corte e sua suplementação na forma micromineral orgânico em dietas práticas de frangos tem sido defendida devido a sua biodisponibilidade, a qual é benéfica para o meio-ambiente, bem como em razão dos resultados sobre variáveis resposta de interesse na produção animal. Um ensaio dose-resposta foi conduzido para avaliar o desempenho, mineralização de tecidos, retenção e respostas fisiológicas de frangos de corte em crescimento alimentados com dietas contendo diferentes fontes e níveis de selênio. Um total de 500 frangos de corte macho da linhagem Cobb 500 com 10 dias de idade foram aleatoriamente designados a 10 tratamentos com 10 repetições e 5 aves por repetição. Os tratamentos foram obtidos de um arranjo fatorial 2×5 onde 2 fontes de Se (selenito de sódio [SS] e selênio-levedura [SL]) foram suplementados em dietas semi- purificadas em 0, 0,08, 0,16, 0,24 e 0,32 mg Se/kg de ração. Aves alimentadas com SL tiveram seu peso corporal (PC) e ganho de peso diário (GPD) otimizados em 0,133 e 0,130 mg Se/kg, respectivamente. As duas fontes de Se aumentaram linearmente (P<0,05) a atividade da glutationa peroxidase (GSH-Px) no sangue de aves, porém valores maiores foram observados em aves supplementadas com SS (P<0,05). As duas fontes de Se infuenciaram a concentração dos hormônios tireoideanos no soro (P<0,05). Aves alimentadas com SL exibiram maior retenção de Se nas penas (P<0,05). Se orgânico suplementado na forma de SL resultou em maior biodisponibilidade do que SS. A suplementação de SL resultou em menor concentração de Se no fígado conforme o aumento dos níveis de Se na dieta (P<0,05). Baseado nas características de desempenho, a suplementação de Se orgânico como SL que garante o crescimento adequado de frango de corte é 0,133 mg Se/kg. Palavras-chave: Glutationa peroxidase. Microminerais orgânicos. Balanço de selênio. Selênio- levedura. Mineralização de tecidos

A Simple Assay to Assess <i>Salmonella</i> Typhimurium Impact on Performance and Immune Status of Growing Pigs after Different Inoculation Doses

Salmonella Typhimurium is the most frequent serovar in pigs and causes infections in humans. However, the dosage used for experimentation is not well defined. The present study aimed to evaluate a dosage for oral inoculation with Salmonella Typhimurium to assess immunological and growth performance alterations in pigs. Gilts were randomly allocated into one of three experimental treatments: no Salmonella Typhimurium inoculation (Basal), or oral inoculation of 1 × 108 or 1.5 × 108 colony-forming units of Salmonella Typhimurium. Growth rate, rectal temperature, and fecal Salmonella shedding were recorded. Blood samples were taken. Inoculated pigs shed the bacteria for up to 7 days, but no differences were observed between the groups. No differences were observed in rectal temperature, body weight, or average daily feed intake. However, reductions in average daily gain (−17 and −22%) and feed efficiency (−14 and −20%) were observed in pigs inoculated with 1 × 108 and 1.5 × 108 colony-forming units, respectively. The hemoglobin and hematocrit concentrations increased in challenged pigs compared to Basal pigs. The oral dosage of 1.5 × 108 colony-forming units of Salmonella Typhimurium is suitable for activating the immune system of pigs and assessing the impact of Salmonella on pig performance

Selenium source and level on performance, selenium retention and biochemical responses of young broiler chicks

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A Simple Assay to Assess Salmonella Typhimurium Impact on Performance and Immune Status of Growing Pigs after Different Inoculation Doses

Salmonella Typhimurium is the most frequent serovar in pigs and causes infections in humans. However, the dosage used for experimentation is not well defined. The present study aimed to evaluate a dosage for oral inoculation with Salmonella Typhimurium to assess immunological and growth performance alterations in pigs. Gilts were randomly allocated into one of three experimental treatments: no Salmonella Typhimurium inoculation (Basal), or oral inoculation of 1 &times; 108 or 1.5 &times; 108 colony-forming units of Salmonella Typhimurium. Growth rate, rectal temperature, and fecal Salmonella shedding were recorded. Blood samples were taken. Inoculated pigs shed the bacteria for up to 7 days, but no differences were observed between the groups. No differences were observed in rectal temperature, body weight, or average daily feed intake. However, reductions in average daily gain (&minus;17 and &minus;22%) and feed efficiency (&minus;14 and &minus;20%) were observed in pigs inoculated with 1 &times; 108 and 1.5 &times; 108 colony-forming units, respectively. The hemoglobin and hematocrit concentrations increased in challenged pigs compared to Basal pigs. The oral dosage of 1.5 &times; 108 colony-forming units of Salmonella Typhimurium is suitable for activating the immune system of pigs and assessing the impact of Salmonella on pig performance

Increased Dietary Trp, Thr, and Met Supplementation Improves Performance, Health, and Protein Metabolism of Weaned Piglets under Mixed Management and Poor Housing Conditions

A sanitary challenge was carried out to induce suboptimal herd health while investigating the effect of amino acids supplementation on piglet responses. Weaned piglets of high sanitary status (6.33 ± 0.91 kg of BW) were distributed in a 2 × 2 factorial arrangement into two similar facilities with contrasting sanitary conditions and two different diets. Our results suggest that increased Trp, Thr, and Met dietary supplementation could support the immune systems of piglets under a sanitary challenge. In this manner, AA+ supplementation improved the performance and metabolism of piglets under mixed management and poor sanitary conditions. No major temporal microbiome changes were associated with differences in performance regardless of sanitary conditions or diets. Since piglets often become mixed in multiple-site production systems and facility hygiene is also often neglected, this study suggests that increased Trp, Thr, and Met (AA+) dietary supplementation could contribute to mitigating the side effects of these harmful risk factors in modern pig farms