Intrauterine growth restriction and its impact on intestinal morphophysiology throughout postnatal development in pigs.

Intrauterine growth restriction (IUGR) compromises fetal development, leading to low birth weight, and predisposes to gastrointestinal disorders. Pigs that suffered IUGR present poor postnatal development, resulting in great economic losses to the industry. The small intestine may be involved with impaired development, but studies investigating this issue are still limited. Thus, the present study aimed to investigate small intestine morphofunctional alterations in IUGR pigs throughout the production phases (birth to 150 days). IUGR pigs presented lower body weight from birth to the finishing phase (P < 0.05). Although histomorphometrical parameters were not affected during the pre-weaning period, their commitment was observed specifically in the duodenum of the IUGR group at older ages (P < 0.05). The most detrimental effects on the small intestine, such as deeper duodenum crypts' depth, lower villus height:crypt depth ratio and absorptive area, increased apoptosis and lower proliferation of the duodenum epithelium were noticed at 70 days of age (P < 0.05). Additionally, IUGR pigs presented the lowest chymotrypsin and amylase activities at 70 and 150 days of age, respectively (P < 0.05). These findings may contribute to the elucidation of morphofunctional disorders of the small intestine in IUGR pigs throughout the different production phases, suggesting that poor postnatal development may be due to intestinal damage.

Alternatives to antibiotics in diets of weaned piglets / Alternativas de antibióticos para leitões desmamados

ABSTRACT: This experiment was conducted to evaluate the effect of growth promoter additives an alternative to antibiotics on performance, intestinal morphology and on microbiota of 21-to-35-day-old piglets. A total of 160 commercial crossbred piglets (males and females) with initial weight of 6.10±0.709kg were allotted in a completely randomized design with five treatments: Basal diet - Negative Control (NC); Basal diet + antibiotic (PC); Basal diet + mannanoligosaccharides (MOS); Basal diet + organic acids (OA), Basal diet + mannanoligosacharides + organic acids (MOS+OA), eight replicates and four piglets per experimental unit. The inclusion of additives in the diets had no effect (P>0.05) on the final average weight of piglets. Similarly, no effects (P<0.05) were observed on average daily feed intake and on average daily weight gain. The feed conversion improved (P<0.01) with the inclusion of additives in the diets compared to piglets fed with the NC. There was no effect (P>0.05) of the dietary additives on intestinal morphology and microbiota composition (enterobacteria and lactobacilli). Use of antibiotics, prebiotics, organic acids or prebiotics associated with organic acids in the diet improves feed conversion of piglets from 21 to 35 days of age. The additives have no major effects on piglets' intestinal morphology and microbiota.

RESUMO: O experimento foi conduzido com o objetivo de avaliar o efeito de aditivos promotores de crescimento como alternativa ao uso de antibióticos no desempenho, na morfologia intestinal e na microbiota de leitões dos 21 aos 35 dias de idade. Um total de 160 leitões híbridos comerciais, machos castrados e fêmeas, com peso inicial de 6,10±0,709kg, foram distribuídos em delineamento inteiramente casualizado, com cinco tratamentos: Ração basal - Controle Negativo (CN); Ração basal + antibiótico (CP); Ração basal +mananoligossacarídeo (MOS); Ração basal + ácido orgânico (AO); Ração basal + mananoligossacarídeo + ácido orgânico (MOS+AO), oito repetições e quarto animais por unidade experimental. A inclusão dos aditivos não teve efeito (P>0,05) no peso médio final dos leitões. Da mesma forma, não foram observados efeitos (P>0,05) dos aditivos no consumo de ração médio diário. A conversão alimentar melhorou (P<0,01) com a inclusão dos aditivos na ração comparados com os animais alimentados com a ração CN. Não houve efeito (P>0,05) dos aditivos na morfologia do epitélio intestinal e na composição da microbiota (enterobactérias e lactobacilos). A utilização de antibiótico, probióticos, ácidos orgânicos ou de probióticos associado com ácidos orgânicos na ração melhora a conversão alimentar de leitões, dos 21 aos 34 dias de idade. Os aditivos não tiveram efeitos na morfologia intestinal e na microbiota dos leitões.