Microbial colonization of the gastrointestinal tract of dairy calves – a review of its importance and relationship to health and performance

Abstract

This review aims to explain how microbial colonization of the gastrointestinal tract (GIT) in young dairy calves is related to health and, consequently, to the performance of these animals. The review addresses everything from the fundamental aspects of microbial colonization to the current understanding about the microbiota manipulation to improve performance in adult animals. The ruminal microbiota is the most studied, mainly due to the high interest in the fermentative aspects, the production of short-chain fatty acids, and microbial proteins, and its effects on animal production. However, in recent years, the intestinal microbiota has gained space between studies, mainly due to the relationship to the host health and how it affects performance. Understanding how the GIT's microbiota looks like and how it is colonized may allow future studies to predict the best timing for dietary interventions as a way to manipulate it and, consequently, improve the health and performance of young ruminants.

Effect of supplementation with algae β-glucans on performance, health, and blood metabolites of Holstein dairy calves

“…However, there was a health benefit to calves who received algae-derived β-glucans, as these calves had a lower likelihood of spending an additional day with abnormal feces. The dysbiosis caused by diarrhea may have effects on the metabolism and performance of preweaning calves (Virgínio Júnior and Bittar, 2021). Consequently, this may positively affect digestion and nutrient absorption, partially explaining the improved FE observed in our calves during wk 3 and 5.…”

The Gut Microbiota of Newborn Calves and Influence of Potential Probiotics on Reducing Diarrheic Disease by Inhibition of Pathogen Colonization

“…Diarrhea is a leading cause of death for beef and dairy calves in their first month of life ( Caffarena et al, 2021 ). The homeostasis of gut microbial ecosystems is of central importance for maintaining the functions of the gastrointestinal tract of early preweaning calves ( Virginio Junior and Bittar, 2021 ). However, there are limited studies reporting relationships between gut microbiota and diarrhea in young beef cattle.…”

Estratégias alimentares para redução das taxas de morbidade em bezerros leiteiros

“…A dieta líquida possui em sua composição oligossacarídeos que selecionam uma microbiota intestinal altamente adaptada, todavia esses importantes componentes têm concentração variável de acordo com a dieta utilizada . Ao utilizar sucedâneos lácteos, o tipo e a disponibilidade de nutrientes são diferentes daquela observada no leite, o que pode trazer grandes impactos na colonização do intestino do bezerro (Virgínio Júnior et al, 2021). Outro fator relacionado ao sucedâneo que impacta na colonização intestinal, é que a taxa de digestão da matéria seca, tende a ser menor em comparação ao leite integral (Hill et al, 2010).…”

“…O processo de acidificação da dieta líquida é uma alternativa interessante para solucionar este problema. Previne o crescimento de vários microrganismos patogênicos, diminui problemas digestivos e diarreicos, melhora o desempenho, melhora a composição bacteriana intestinal e aumenta a população de microrganismos benéficos como Bifidobacterium e Lactobacillus (Virgínio Júnior et al, 2021;Todd et al, 2017;Coelho et al, 2020;Zou et al, 2017).…”

“…A maior incidência de diarreia nas primeiras semanas de vida pode afetar a homeostase dos ecossistemas microbianos intestinais (Virgínio Júnior et al, 2021). A microbiota tem demonstrado ser peça central para a manutenção da boa saúde e das principais funções dos organismos animais, O presente estudo foi realizado no Bezerreiro Experimental da Escola Superior de Agricultura 'Luiz de Queiroz', Universidade de São Paulo, Brasil, de fevereiro a maio de 2019.…”