Gut health in animals is a growing area of scientific research, but important knowledge gaps remain in several species, including horses, researchers report.
Most of the research in the field since 2000 has focused on pigs, poultry and animals used in aquaculture.
Elena Colombino, Daniel Prieto-Botella and Maria Teresa Capucchio set out in their study to examine the nature of gut-related veterinary research for the 21 years between 2000 and 2020. They examined the number of studies published, the species of interest, and the areas of gut research on which the scientists focused.
The trio, writing in the journal Animals, said they retrieved 1696 documents from the Web of Science database, indicating a constant annual growth in the number of publications of 22.4% in this field of research.
Pigs (34.8%), poultry (33.9%) and aquaculture (15.0%) were the most studied species. They described the number of publications found on horses, felines, cows, rodents, goats and sheep as scarce.
China was responsible for most of the research, at 24.7%, followed by the United States (17.2%) and Canada (5.7%).
The study team identified three main research lines in relation to gut health: Animal nutrition, prevention of inflammatory diseases, and microbiota composition.
In all, 317 journals were found to have published articles related to gut health research in animals. Only 55 studies were identified that covered either horses, felines, cows, goats or sheep, which in total represented only 3.2% of all gut health research.
The researchers said a lack of knowledge on gut health in relation to ruminants, horses, rabbits, cats and dogs was detected. “A possible explanation for this gap is the difficulty in conducting research in these animals, particularly ruminants and pets,” they said.
“On the one hand, ruminants have a longer production cycle and require bigger spaces for their rearing compared to other species, making them difficult to use in research. On the other, companion animals are more difficult to enrol for clinical trials or research works and non-invasive procedures must be preferred, representing a potential limitation for researchers.”
They continued: “Future research could focus on the evaluation of gut health in the abovementioned less investigated species in order to explore factors such as nutrition, zootechnical parameters, immunology, gene expression, oxidative stress and microbiota, that have been already explored in pigs, poultry and aquaculture.”
Regardless of the species, future investigations should look further into the gut-brain axis and its function, or the potential of fecal microbiota transplants as a treatment for gastrointestinal diseases.
Colombino and Capucchio are with the University of Turin in Italy; Prieto-Botella is with Miguel Hernandez University in Spain.
Colombino, E.; Prieto-Botella, D.; Capucchio, M.T. Gut Health in Veterinary Medicine: A Bibliometric Analysis of the Literature. Animals 2021, 11, 1997. https://doi.org/10.3390/ani11071997