ABSTRACT: This study evaluated the effect of black wattle (Acacia mearnsii) condensed tannin extract in simple and complex diets for weaned piglets on performance, faecal consistency and serum haptoglobin concentrations. Eighty-eight female and castrated male piglets were used, weaned at 28 ± 3 days old, with an initial body weight of 8.02 ± 1.21 kg, housed in same-sex pairs and distributed in four treatments in a 2 x 2 factorial experiment in a randomised complete block design. The experimental treatments were simple diet (SD), simple diet + tannin (SD+T), complex diet (CD) and complex diet + tannin (CD+T). The simple diets contained lower concentrations of dairy ingredients, inclusion of barley and no addition of zinc oxide, palatant, acidifier and yeast. The diets with tannin were supplemented with 1,850 mg kg-1 of black wattle condensed tannin extract. The feed programme consisted of three diets: Pre-starter I (0-7 days), Pre-starter II (8-21 days) and Starter (22-28 days). Feed and water were available ad libitum. Body weight and feed intake were measured weekly to calculate the average daily feed intake, daily weight gain and feed conversion ratio. The faecal consistency score was measured daily to calculate the diarrhoea occurrence percentage. Blood samples for serum haptoglobin concentration were collected at 7 and 14 days after weaning. The addition of condensed tannin had no effect (P > 0.05) on evaluated performance variables for weaned piglets. The diet type also did not affect the piglets’ performance (P > 0.05). The inclusion of black wattle (Acacia mearnsii) condensed tannin does not affect piglet performance, reduces the incidence of diarrhoea in the first week after weaning and decreases the haptoglobin inflammatory response.

RESUMO: O objetivo do estudo foi avaliar o efeito de extrato de tanino condensado de acácia-negra (Acacia mearnsii) no desempenho, consistência fecal e concentração sérica de haptoglobina em leitões na fase de creche. Foram utilizados 88 leitões desmamados aos 28±3 dias, com peso vivo médio inicial 8,02 ± 1,21 kg, alojados em duplas de mesmo sexo, e distribuídos em quatro tratamentos em um delineamento de blocos inteiramente ao acaso, em esquema fatorial 2 x 2. Os tratamentos experimentais foram: dieta simples (SD); dieta simples + tanino (SD+T); dieta complexa (CD) e dieta complexa + tanino (CD+T). As dietas simples foram formuladas com menores concentrações de derivados de leite, inclusão de cevada e sem adição de óxido de zinco, palatabilizante e levedura. As dietas com inclusão de tanino foram suplementadas com 1850 mg kg-1 de extrato concentrado de tanino de acácia negra. O programa alimentar foi constituído de três dietas: Pré-inicial I (0 a 7 dias), Pré-inicial II (8 a 21 dias) e Inicial (22 a 28 dias). Ração e água ficaram disponíveis ad libitum. O peso e o consumo de ração dos leitões foram mensurados semanalmente, para calcular a média diária de consumo, o ganho de peso diário e a conversão alimentar. O índice de consistência fecal foi medido diariamente para calcular a porcentagem de ocorrência de diarreia. Amostras de sangue para concentração sérica de haptoglobina foram coletadas aos sete e 14 dias após o desmame. A adição de tanino condensado não teve efeito (P > 0,05) no desempenho de leitões desmamados. O tipo de dieta também não afetou o desempenho dos leitões (P > 0,05). A inclusão do tanino condensado de acácia-negra (Acacia mearnsii) não afetou desempenho, reduziu a incidência de diarreia na primeira semana após o desmame, e diminuiu a resposta inflamatória da haptoglobina.

ABSTRACT This study aimed to evaluate the use of decision trees to select sows based on the production parameters of parity order (PO) 1 sows from a commercial herd. Data were collected at a piglet production unit with a capacity of housing 5,500 sows in collective pens. Piglet production and sow culling information was collected from PO1 and PO2 sows. The period from January 2017 to March 2020 was analyzed. The correlation analysis was used to identify the influence of the production parameters on sow culling after exploring the database using the graphical analysis and descriptive statistics. The ANOVA was applied to evaluate differences in the response variables between culled and unculled sows. Two models were proposed using the decision tree method: model 1 referred to sow culling, and model 2 comprised the total number of liveborn piglets (TBA). The calculated value was close to 0, although the correlations of the production parameters with culling were statistically significant. The mean number of weaned piglets was higher for unculled sows in PO1 (p < 0.05). The number of weaned piglets, total number of liveborn piglets, and weaning-service interval did not differ in the unculled and culled sows in PO2 (p > 0.05). Using a confusion matrix as a metric tool, the decision tree method used in this study provided consistent results for this database, indicating its possible use for decision-making in sow selection.

To evaluate the effects of glutamine (Gln) supplementation on sow performance during late gestation and lactation and their offspring, eighty pregnant, multiparous sows of a commercial hybrid line were used in a completely randomized, 2 χ 2 experimental design at the end of gestation and lactation, respectively. Females were subjected to a control diet or a Gln-supplemented diet (1% of L-glutamine) from 85 d of gestation until farrowing. During lactation, the dietary treatment groups were CON_C: without Gln supplementation; CON_G: Gln only during lactation; GLN_C: Gln only during gestation; GLN_ GLN: Gln during gestation and lactation. At 105 d of gestation, there was no statistical difference regarding the body weight of the sows, however, sows fed the Gln-supplemented diet had greater backfat thickness at P1 and loin depth at P2 than control sows. Placental weight and efficiency showed no effect between treatments. Litters born from Gln-supplemented sows tended to be heavier at birth compared to control litters, reducing the probability of piglets weighing less than 1.5 kg. In addition, litters from supplemented sows had a lower standard deviation of BW at birth. There were no effects of dietary treatments on the performance of sows and offspring during the lactation period. Maternal Gln supplementation during late gestation improved piglet weight and litter uniformity at birth without affecting sow body composition after farrowing.

Abstract 19. In the last decades, infections by several serovars of Salmonella have become relevant worldwide, not only due to their impact on veterinary health and animal production, but also because they may serve as a source of infection for the human population. Pigs can be infected by several Salmonella serovars, being S. Typhimurium one of the most frequently isolated worldwide. In this context, the evaluation of strategies to control Salmonella in farms demands the understanding of the pathogenesis of the microorganism. Thus, the objective of this work was to carry out an experimental infection in 50-day-old pigs using a field strain of S. Typhimurium to evaluate the excretion of the microorganism, organs colonization and the development of histological injuries over the 13-day trial period. Disease was successfully reproduced in eight animals, and two clinical patterns were identified. In four animals, a primarily enteric pattern was observed, where the infection was limited to the gastrointestinal tract, while in another four pigs, enteric and systemic infection with variable fecal excretion and invasion of internal organs was observed. These two infectious patterns were accompanied by changes in fecal consistency and reduced daily weight gain or weight loss in the animals. The observation of two different infectious patterns highlights the need to consider the complexity of the pathogenicity of Salmonella Typhimurium infection in pigs.

Resumen. 23. En las últimas décadas las infecciones por diferentes serovariedades de Salmonella han adquirido importancia a nivel mundial, no solo por su impacto en la sanidad y en la producción de los animales, sino también porque estos constituyen una fuente de infección para los humanos. Los cerdos pueden estar infectados o ser portadores de distintas serovariedades con potencial zoonótico, siendo S. Typhimurium una de las más frecuentemente aisladas a nivel mundial. En este contexto, la evaluación de estrategias para el control de Salmonella en granjas exige el conocimiento de la patogenia del microorganismo. El objetivo de este trabajo fue realizar una infección experimental en cerdos de 50 días de edad utilizando una cepa de campo de S. Typhimurium para evaluar la excreción del microorganismo, la colonización de órganos y el desarrollo de lesiones histológicas durante los 13 días del ensayo. Se logró reproducir la enfermedad en ocho animales y se pudo identificar dos cuadros clínicos. En cuatro animales se observó un cuadro principalmente entérico, en el que la infección estuvo limitada al tracto gastrointestinal; mientras que en otros cuatro cerdos se observó infección entérica y sistémica con excreción fecal variable e invasión de órganos internos. Estos dos cuadros infecciosos estuvieron acompañados de cambios en la consistencia de la materia fecal y menor ganancia diaria de peso o adelgazamiento de los animales. La observación de dos cuadros infecciosos diferentes muestra la necesidad de considerar la complejidad de la patogenicidad de la infección por Salmonella Typhimurium en cerdos.

Abstract Objective Testing an experimental model for ischemic necrosis of the femoral head in Legg-Calvé-Perthes disease by evaluating gait, imaging and morphohistology. Methods The operation was done in 11 piglets. Necrosis by cerclage in the right femoral neck was induced. Piglets were divided into group A, with 8 animals, euthanizing two in the 2nd, 4th, 6th, and 8th weeks, respectively; and group B, with 2 animals (sham), submitted to the surgical procedure without cerclage of the right femoral neck. The gait classification used was that of Etterlin. The frozen femurs were submitted to digital radiography and computed tomography. The height and width of the epiphysis and epiphysary coefficient were measured at study times. Light microscopy and immunohistochemistry with TGF-β1 were performed. Results One animal died of sepsis in Group A. In this group, claudication was observed in all animals. On digital radiography and computed tomography, bone sclerosis, enlargement of the right femoral neck, flattening, collapse, and fragmentation of the right femoral head were observed. All epiphysis height and epiphysary coefficient values of the right femoral head were lower than the contralateral ones, in which were observed chondrocytes disordered and separated by gaps. A reduction in TGF-β1 expression was observed at 2 and 6 weeks in the right femoral head and at eight in the left. In group B, there were no signs of necrosis and gait was normal. Conclusions The model presented reproduced macroscopic necrosis on digital radiography, computed tomography, and microscopy. Gait evaluation showed a good correlation with other ischemia findings. Level of EvidenceV. Diagnostic studies.

Resumo Objetivo Testar um modelo experimental para necrose isquêmica da cabeça femoral na doença de Legg-Calvé-Perthes avaliando a marcha, exames de imagens e morfohistologia. Métodos Operaram-se 11 leitões. Induziu-se a necrose por cerclagem no colo femoral direito. Dividiram-se os leitões em grupo A com 8 animais, sacrificando-se dois na 2ª, 4ª, 6ª e 8ª semanas, respectivamente; e grupo B, com 2 animais (sham), submetidos ao procedimento cirúrgico sem a cerclagem do colo femoral direito. A classificação da marcha utilizada foi a de Etterlin. Os fêmures congelados foram submetidos à radiografia digital e tomografia computadorizada. Mediram-se a altura e largura da epífise e o coeficiente epifisário nos tempos de estudo. Realizou-se, microscopia de luz e imunohistoquímica com TGF-β1. Resultados Um animal morreu por sepse no grupo A. Neste grupo, observou-se claudicação em todos os animais. Na radiografia digital e tomografia computadorizada observaram-se: esclerose óssea, alargamento do colo femoral direito, achatamento, colapso e fragmentação da cabeça femoral direita. Todos os valores da altura da epífise e coeficiente epifisário da cabeça femoral direita foram menores que os contralaterais, nos quais observaram-se condrócitos desordenados e separados por lacunas. Observou-se redução da expressão do TGF-β1 com 2 e 6 semanas nas cabeças femorais direitas e nas esquerdas com oito. No grupo B, não ocorreram sinais de necrose e a marcha foi normal. Conclusões O modelo apresentado reproduziu a necrose macroscopicamente, na radiografia digital, tomografia computadorizada e microscopia. A avaliação da marcha demonstrou boa correlação com os demais achados de isquemia. Nível de EvidênciaV. Estudos diagnósticos.

Resumen Introducción. La cerda moderna tiene la capacidad genética de producir un mayor número de lechones por camada y una mayor producción de leche, lo que conlleva que el animal tenga mayores requerimientos de nutrientes. Objetivo. Evaluar el desempeño productivo de las cerdas y su progenie a la suplementación de un producto comercial a base de extracto seco de alcuacil (Cynara scolymus) e hidrocloruro de betaína durante el período de lactancia. Materiales y métodos. El estudio se llevó a cabo durante el primer semestre del año 2020, en la provincia de Limón, Costa Rica. Se utilizaron un total de 42 cerdas en etapa de lactancia que fueron distribuidas en tres tratamientos: dieta control (T1), dieta control + 0,25 kg t-1 de producto comercial (T2) y dieta control + 0,50 kg t-1 de producto comercial (T3), todos los tratamientos fueron isoproteicos e isoenergéticos. Resultados. La inclusión del aditivo mostró una tendencia a la mejora (p=0,09) de los parámetros evaluados en la cerda. La pérdida de condición corporal al final de la lactancia fue menor (p=0,03) en T2, mientras que la suplementación con 0,50 kg t-1 de producto comercial presentó resultados intermedios. Los parámetros evaluados en la camada (peso al destete, ganancia de peso y cantidad de lechones destetados por cerda) no presentaron diferencias significativas (p>0,05) entre tratamientos. Conclusión. El uso del aditivo mostró una tendencia a mejorar el consumo de alimento en la cerda durante la etapa de lactancia, lo que disminuyó las pérdidas de peso y condición corporal durante este periodo. La inclusión del aditivo no mejoró el desempeño productivo de los lechones.

Abstract Introduction. The modern sow has the genetic capacity to produce a greater number of piglets per litter and a higher milk production, which means that the animal has higher nutrient requirements. Objective. To evaluate the performance of sows and their progeny to the supplementation of a commercial product based on artichoke dry extract (Cynara scolymus) and betaine hydrochloride during the lactation period. Materials and methods. The study was carried out during the first semester of 2020, in the province of Limón, Costa Rica. A total of 42 lactating sows were used and distributed in three treatments: control diet (T1), control diet + 0.25 kg t-1 of commercial product (T2), and control diet + 0.50 kg t-1 of commercial product (T3); the diets were isoproteic and isocaloric. Results. The inclusion of the additive showed a tendency to improve (p=0.09) the parameters evaluated in the sow. Body condition score loss was lower (p=0.03) with the T2, while supplementation with 0.50 kg t-1 presented intermediate results. There were no significant differences (p>0.05) between treatments for the parameters evaluated in the litters (weaning weight, weight gain, and number of weaned piglets by sow). Conclusion. The use of the additive showed a tendency to improve feed intake in the sow during the lactation period, reducing body weight loss and corporal condition during this period. The inclusion of the additive did not improve the performance in the piglets.

Resumen. El Síndrome Respiratorio y Reproductivo del Cerdo (PRRS) es una enfermedad endémica en porcinos que tiende a la cronicidad. Los esfuerzos se centran en prevención y control para minimizar el daño, pues no existe tratamiento. Se evaluó el efecto de la adición de ácido docosahexaenoico (DHA) y oleorresina de cúrcuma y capsicum (EP, extractos de plantas) en la alimentación de cerdas reproductoras afectadas con PRRS sobre su desempeño productivo, de salud y en su progenie. Cuarenta y ocho cerdas de primer parto se distribuyeron al azar en cuatro tratamientos (Tr1, testigo; Tr2, DHA; Tr3, EP; Tr4, DHA+EP). El ensayo con el segundo parto siguió el mismo diseño. Tr3 y Tr4 obtuvieron más peso de lechones al nacer en ambos partos (P < 0.05) que los demás. En ambos partos, la adición de DHA y EP resultó en menos cantidad de momias (P < 0.05) y menor costo que los otros tratamientos. Tr3 tuvo mayor número de lechones vivos en ambos partos, mientras que Tr4 solo en el segundo parto (P < 0.05). En el primer parto, se destetaron más lechones en Tr2 y Tr3 (P > 0.05); pero Tr2 superó a los demás en el segundo parto (P > 0.05). Por ELISA, todos los cerdos desarrollaron anticuerpos contra PRRS. Los grupos que recibieron DHA y/o EP tuvieron concentraciones séricas de IgG superiores al testigo (P < 0.05). Se concluye que la adición de DHA y EP mejora la respuesta productiva y mayores concentraciones de IgG en ambos partos, además de reducir el costo de producción de las cerdas.

Abstract. Pig Respiratory and Reproductive Syndrome (PRRS) is an endemic disease in pigs that tends to become chronic. Efforts are focused on prevention and control to minimize damage, as no treatment exists. The effect of adding docosahexaenoic acid (DHA) and turmeric oleoresin and capsicum (plant extracts, PE) in the feeding of breeding sows affected with PRRS on their productive performance, health and progeny was evaluated. Forty-eight first-parturition shows were randomly distributed into four treatments (Tr1, control; Tr2, DHA; Tr3, PE; Tr4, DHA+PE). The second parturition assay followed the same design. Tr3 and Tr4 got more piglet weight at birth in both parturitions (P < 0.05) than the others. In both deliveries, the addition of DHA and PE resulted in fewer mummies (P < 0.05) and lower cost than the other treatments. Tr3 had a higher number of live piglets in both parturitions, while Tr4 only got that in the second parturition (P < 0.05). More piglets were weaned in Tr2 and Tr3 (P > 0.05) in the first parturition; but Tr2 outperformed the others in the second parturition (P > 0.05). By ELISA, all pigs developed antibodies against PRRS. The groups receiving DHA and/or PE had higher serum IgG concentrations than control (P < 0.05). It is concluded that the addition of DHA and PE improves the productive response and induced higher concentrations of IgG in both parturitions, in addition to reducing the production cost of sows.

ABSTRACT The objective of this study was to evaluate the effects of diets composed of corn grain silage rehydrated with water and acid whey on the productive performance and feed preference of weaned piglets. We evaluated 120 piglets weaned in the pre-initial phase I for productive performance, and diarrhea, depression, and thinness states using the following diets: control ration with dry corn grain (CR); and corn grain silage rehydrated with water (CGSR+W); water and inoculant (CGSR+WI); and acid whey (CGSR+AW). To determine feed preference, 20 weaned piglets received reference (CR) and test (CGSR+AW) diets in two phases, restricted and free-choice. Analysis of variance, chi-square test, and t-test were applied at 5% of significance. There were no differences (p>0.05) in growth performance among piglets fed the four experimental diets. Severe thinness and depression were recorded among piglets fed CGSR+W and CR (p<0.05). In the restricted phase, consumption of CGSR+AW resulted in higher daily feed intake (DFI) (p<0.05), while piglets in the free-choice phase showed a higher DFI and spent more time consuming CR, with a 56.39% preference (p<0.05). Rehydrated corn grain silage promoted feed acceptability and performance of piglets in the first weeks post-weaning.

RESUMO O objetivo do presente estudo foi avaliar os efeitos de dietas compostas de silagem de grão de milho reidratado com água e soro de leite no desempenho produtivo e preferência alimentar de leitões desmamados. Foram avaliados 120 leitões desmamados durante a fase pré-inicial I para o desempenho de crescimento, escores de diarreia, depressão e magreza submetidos às dietas: grão de milho seco (CR); silagem de grão de milho reidratado com água (CGSR+W); água e inoculante (CGSR+WI); soro de leite (CGSR+AW). Para avaliar a preferência alimentar, 20 leitões desmamados receberam dieta referência (CR) e dieta teste (CGSR+AW) em duas fases, restrita e livre escolha. Foi aplicado análise de variância, teste de qui-quadrado e t-test à 5% de significância. Não houve diferenças (p>0,05) no desempenho de crescimento entre os leitões alimentados com as quatro dietas experimentais. Leitões alimentados com CGSR+W e CR foram severamente magros e apresentaram escore de depressão (p<0,05). Na fase restrita o CDR foi maior para CGSR+AW (p<0.05), enquanto na fase de livre escolha os leitões mostraram maior CDR e passaram maior tempo consumindo a CR, com preferência de 56,39% (p<0.05). A CGSR promoveu melhor aceitabilidade e desempenho dos leitões nas primeiras semanas pós-desmame.

ABSTRACT The aim of study was to determine the relationship between metabolic parameters, body weight and body growth of piglets at birth and weaning. The experiment included 80 piglets obtained from F1 generation sows. Body weight was measured at birth (BW0), 24h (BW1) after birth and on day 25 (at weaning, BW2). Blood sampling was performed at the beginning of life (3rd day after birth) and at weaning (21st day after birth). BW0 and BW1 positively correlated with cholesterol and negatively with urea values at the beginning of life and RBC values at weaning. BW2 positively correlates with albumin and cortisol values at the beginning of life, total proteins, and globulins at weaning, and negatively correlates with erythrocyte values at weaning. Piglet growth from birth to weaning (BWG2-0) correlates positively with total proteins, albumin, and cortisol at the beginning of life and total proteins at weaning. ROC analysis shows that MCHC, TPROT, GLOB, CHOL and AST at the beginning of life can distinguish fast-growing from slow-growing piglets from birth to weaning period. The use of blood parameters enables early recognition of growth rate in piglets, which can help to optimize all further steps to achieve the best possible growth.

RESUMO O objetivo do estudo foi determinar a relação entre parâmetros metabólicos, peso corporal e crescimento corporal de leitões ao nascimento e desmame. A experiência incluiu 80 leitões obtidos de porcas da geração F1. O peso corporal foi medido ao nascimento (BW0), 24h (BW1) após o nascimento e no dia 25 (no desmame, BW2). A amostragem de sangue foi realizada no início da vida (3º dia após o nascimento) e no desmame (21º dia após o nascimento). BW0 e BW1 correlacionaram-se positivamente com o colesterol e negativamente com os valores de uréia no início da vida e com os valores de hemácias no desmame. BW2 correlaciona-se positivamente com os valores de albumina e cortisol no início da vida, proteínas totais e globulinas no desmame, e negativamente com os valores de eritrócitos no desmame. O crescimento do leitão desde o nascimento até o desmame (BWG2-0) se correlaciona positivamente com as proteínas totais, albumina e cortisol no início da vida e com as proteínas totais no desmame. A análise ROC mostra que MCHC, TPROT, GLOB, CHOL e AST no início da vida pode distinguir leitões de crescimento rápido de leitões de crescimento lento desde o nascimento até o desmame. O uso de parâmetros sanguíneos permite o reconhecimento precoce da taxa de crescimento em leitões, o que pode ajudar a otimizar todas as etapas posteriores para alcançar o melhor crescimento possível.

RESUMO: Os suínos são animais que apresentam dificuldade em realizar trocas de calor, por esse motivo é importante considerar os fatores ambientais que impactam seu desempenho produtivo. O objetivo do presente trabalho foi avaliar o efeito do conforto térmico e do fotoperíodo, sobre o desempenho produtivo das porcas na gestação e leitões na maternidade. Os dados zootécnicos foram obtidos de uma granja comercial. O índice de temperatura e umidade (ITU) foi utilizado como parâmetro para o conforto ou o estresse térmico da matriz. Foram analisados os parâmetros das fêmeas no período gestacional e dos leitões na maternidade, considerando os critérios de conforto, estresse e quatro faixas de fotoperíodos. A correlação entre o fotoperíodo e ITU foi alta e positiva, demonstrando efeito associado dessas variáveis. Foram observados mais efeitos significativos em situações de conforto e faixas de menor fotoperíodo. Em conclusão, o conforto térmico e o fotoperíodo influenciaram os parâmetros avaliados na gestação e na maternidade e a alta associação ITU e fotoperíodo sugere que o controle ambiental pode favorecer parâmetros produtivos em granjas comerciais.

ABSTRACT: Pigs have difficulty in performing heat exchange and; therefore, it is important to consider the environmental factors that impact their productive performance. This study evaluated the effect of thermal comfort and photoperiod on the productive performance of sows during pregnancy and of nursery piglets. Zootechnical data were obtained from a commercial farm. The temperature-humidity index (THI) was used as the parameter to determine comfort or thermal stress of the sow. The parameters of the sows during pregnancy and nursery piglets were analyzed considering the criteria of comfort, stress, and four photoperiods. The correlation between photoperiod and THI was high and positive, which demonstrated the associated effect of these variables. More significant effects were observed under conditions of comfort and shorter photoperiods. In conclusion, thermal comfort and photoperiod influenced the parameters evaluated during pregnancy and in the nursery, and the strong association between THI and photoperiod suggested that environmental control favors productive parameters in commercial farms.

RESUMO: Neste estudo, o objetivo foi avaliar diferentes abordagens de sistematização e meta-análise sobre o uso de ácidos cítrico e ascórbico no desempenho de leitões de creche. O estudo incluiu 24 publicações entre 1985 e 2018 (moda 1998), totalizando 4215 leitões de creche. O índice de Higgins indicou alta heterogeneidade entre os estudos envolvendo ácido cítrico (96,9%) e ácido ascórbico (91,4%). Na análise por forest plot a adição de ácido ascórbico em dietas de leitões não melhora (P > 0.05) o ganho de peso de leitões em creche. Na abordagem de meta-análise proposta por LOVATTO et al. (2007) e SAUVANT et al. (2008) não houve efeito significativo (P > 0.05) da adição de ácidos cítrico e de ascórbico no desempenho dos leitões. Numericamente, observou-se aumento do ganho de peso (Δ > 0) relacionado aos ácidos (suplementado em relação aos tratamentos controle) observado em 59.7% (acido ascórbico) e 46.6% (ácido cítrico) das comparações do ganho de peso diário. A suplementação de ácido ascórbico em relação ao tratamento controle no período total de creche teve variação de 0,98%, 1,07% e -1,3% para ADFI, ADG e FCR, respectivamente. A adição de ácido cítrico em relação ao tratamento controle teve variação de 1,67%, 4,40% e -2,29 para ADFI, ADG e FCR. A adição de ácidos cítrico e ascórbico em dietas para leitões de creche não altera o desempenho, independentemente da abordagem de meta-análise utilizada.

ABSTRACT: This study evaluated different meta-analytical approaches tousing citric and ascorbic acids in the performance of nursery piglets. The study included 24 publications between 1985 and 2018 (mode 1998), totaling 4215 nursery piglets. The Higgins index indicated high heterogeneity (98.5%) among the studies concerning citric acid (96.9%) and ascorbic acid (91.4%). In variances and forest plot analysis, using citric and ascorbic acids and their analogs was no significant effect (P > 0.05) on piglet weight gain. In the meta-analysis approach proposed by LOVATTO et al. (2007) and SAUVANT et al. (2008), there was no significant effect (P > 0.05) of the addition of citric and ascorbic acids on piglet performance. Numerically, was observed an increased ADG (Δ > 0) related to acids (supplemented over control treatments) in 59.7% (ascorbic acid) and 46.6% (citric acid) of the ADG comparisons. The effect of ascorbic supplementation on the respective control treatment of the overall nursery period was on average 0.98%, 1.07%, and -1.3% for ADFI, ADG, and FCR, respectively. Citric acid supplementation to the respective control treatment of the overall nursery period was on average 1.67%, 4.40%, and -2.29% for ADFI, ADG, and FCR. Adding citric and ascorbic acids in diets for nursery piglets does not alter performance regardless of the meta-analysis method used.

Yeast hydrolysate (YH) is rich in amino acids, small peptides, B vitamins, glutathione, and nucleotides, which makes it a possible substitute for spray-dried plasma powder (SDPP). This research was conducted to estimate the application of YH instead of SDPP in creep feed of weaned piglets. The experiment had four treatment groups: (1) basal diet (CON group), (2) CON + 4% YH (YH group), (3) CON + 2% YH + 2% SDPP (SY group), and (4) CON + 4% SDPP (SDPP group). Growth performance, biochemical parameters, immunoglobulin levels, and intestinal tissue morphology were measured. No substantial difference in growth performance between the YH, SY, and SDDP groups was found; however, compared with the CON group, the performance of these three groups was substantially improved. The contents of serum globulin and ALP in the CON group were markedly decreased compared to the other groups, but the AST level was substantially increased. The IL-10 concentration in the other groups was substantially higher than the CON group, and the highest content was in group YH; the TNF-α content showed an opposite trend. The levels of serum IgG and IgA in the CON group were the lowest among all groups. There were substantial differences among the groups in villi height and crypt depth in the duodenum, jejunum, and ileum. The results showed that YH effectively increased IL-10 concentration and decreased TNF-α level to promote intestinal development, while not differing from SDPP in terms of growth performance.

Piglets experience stresses that impact intestinal homeostasis and result in a high incidence of diarrhoea and reduced growth performance during weaning. Recent studies have indicated that gastrointestinal tract microbiota can be nutritionally regulated in ways that can benefit and promote gut health in weaning piglets. In this review, we discuss different components of nutrition and their effects on microbial populations, diversity, and activity and, in turn, how these altered microbial structures and activities affect gut health in weaning piglets. In addition, we discuss some of the inner mechanisms through which microbiota regulate and exert their effects on gut health, focusing particularly on adaptive and innate immunity, inflammatory responses and intestinal barrier integrity. Most of the mechanisms involve the TLR and NF-kB signalling pathways, and miRNA regulation. An understanding of the effects of nutritional regulation of microbiota on gut health and its underlying mechanisms can be applied in developing nutritional regimens that promote beneficial microbial structures for gut health.

This study aimed to assess the effects of starting creep feeding at different ages on performance, behaviour, haematological, and biochemical parameters in piglets. A total of 138 piglets (1.34 ± 0.25 kg, n = 13 sows), weaned at 21 d-old, were assigned to treatments using a completely randomized design. The litter was divided into two groups: seven litters (n = 80 piglets) were subjected to creep feeding on the fifth day of age (creep 5) and five litters (n = 58 piglets), on the tenth day of age (creep 10). Piglets were weighed at birth, weaning, and after the first week in the nursery. Piglet behaviour was evaluated daily for 15 min until day 20. Blood was collected on day 13, at weaning, and at the end of the first week in the nursery. There was no difference in body weight in the suckling phase, but piglets fed Creep 5 showed greater body weight gain in the first nursery week. The Creep 5 group had lower feed leftovers during the five days of evaluation of feed intake. There were no differences in haematological parameters and amylase concentration; however, the piglets spent more time lying down, sucking, and massaging the udder. On day 8, the piglets in the Creep 5 group showed a higher frequency of exploratory behaviour. In conclusion, piglets fed Creep 5 had optimal performance after weaning and improved feed intake capacity by displaying more exploratory behaviour than Creep 10. Creep management did not alter haematological and biochemical parameters.

This study aimed to assess the effects of starting creep feeding at different ages on performance, behaviour, haematological, and biochemical parameters in piglets. A total of 138 piglets (1.34 ± 0.25 kg, n = 13 sows), weaned at 21 d-old, were assigned to treatments using a completely randomized design. The litter was divided into two groups: seven litters (n = 80 piglets) were subjected to creep feeding on the fifth day of age (creep 5) and five litters (n = 58 piglets), on the tenth day of age (creep 10). Piglets were weighed at birth, weaning, and after the first week in the nursery. Piglet behaviour was evaluated daily for 15 min until day 20. Blood was collected on day 13, at weaning, and at the end of the first week in the nursery. There was no difference in body weight in the suckling phase, but piglets fed Creep 5 showed greater body weight gain in the first nursery week. The Creep 5 group had lower feed leftovers during the five days of evaluation of feed intake. There were no differences in haematological parameters and amylase concentration; however, the piglets spent more time lying down, sucking, and massaging the udder. On day 8, the piglets in the Creep 5 group showed a higher frequency of exploratory behaviour. In conclusion, piglets fed Creep 5 had optimal performance after weaning and improved feed intake capacity by displaying more exploratory behaviour than Creep 10. Creep management did not alter haematological and biochemical parameters.