Animal husbandry is increasingly under pressure to meet world food demand. Thus, strategies are sought to ensure this productivity increment. The objective of this review was to gather advances in the use of bacterial probiotics in animal production. Lactobacilli correspond to the most used bacterial group, with several beneficial effects already reported and described, as well as the Enterococcus and Pediococcus genera – being the latter expressively used in aquaculture. Research on the Bifidobacterium genus is mostly focused on human health, which demonstrates great effects on blood biochemical parameters. Such results sustain the possibility of expanding its use in veterinary medicine. Other groups commonly assessed for human medicine but with prospective expansion to animal health are the genera Leuconostoc and Streptococcus, which have been demonstrating interesting effects on the prevention of viral diseases, and in dentistry, respectively. Although bacteria from the genera Bacillus and Lactococcus also have great potential for use in animal production, a complete characterization of the candidate strain must be previously made, due to the existence of pathogenic and/or spoilage variants. It is noteworthy that a growing number of studies have investigated the genus Propionibacterium, but still in very early stages. However, the hitherto excellent results endorse its application. In this way, in addition to the fact that bacterial probiotics represent a promising approach to promote productivity increase in animal production, the application of other strains than the traditionally employed genera may allow the exploitation of novel mechanisms and enlighten unexplored possibilities.

Antibiotic resistance has become a major health concern globally, with current predictions expecting deaths related to resistant infections to surpass those of cancer by 2050. Major efforts are being undertaken to develop derivative and novel alternatives to current antibiotic therapies in human medicine. What appears to be lacking however, are similar efforts into researching the application of those alternatives, such as (bacterio)phage therapy, in veterinary contexts. Agriculture is still undoubtedly the most prominent consumer of antibiotics, with up to 70% of annual antibiotic usage attributed to this sector, despite policies to reduce their use in food animals. This not only increases the risk of resistant infections spreading from farm to community but also the risk that animals may acquire species-specific infections that subvert treatment. While these diseases may not directly affect human welfare, they greatly affect the profit margin of industries reliant on livestock due to the cost of treatments and (more frequently) the losses associated with animal death. This means actively combatting animal infection not only benefits animal welfare but also global economies. In particular, targeting recurring or chronic conditions associated with certain livestock has the potential to greatly reduce financial losses. This can be achieved by developing novel diagnostics to quickly identify ill animals alongside the design of novel therapies. To explore this concept further, this review employs Johne's disease, a chronic gastroenteritis condition that affects ruminants, as a case study to exemplify the benefits of rapid diagnostics and effective treatment of chronic disease, with particular regard to the diagnostic and therapeutic potential of phage.

This study aimed to highlight the roles of different minerals, serum metabolites, and hormones related to reproductive health of cattle as these have a significant role in cattle production and reproduction. Minerals are known for their contribution to several physiological processes such as cell formation and are paramount for physiological functions of vitamins, enzymes, and hormones. Evaluations of serum metabolites are good indicators of disease diagnosis and nutritional status in animals. Hormonal imbalance before and during pregnancy can negatively impact an overall bovine reproductive health. Minerals are important for reproduction, serum metabolites are a reliable indicator as their changes have been related to many disorders in reproduction, and hormones are significant indicators in cows presenting different reproductive conditions.

Ectoparasites are important to the one health concept because their parasitism can result in the transmission of pathogens, allergic reactions, the release of toxins, morbidity, and even death of the host. Ectoparasites can affect host physiology, as reflected in immune defenses and body condition as well as hematological and biochemical parameters. Thus, evidence that ectoparasites influence host hematological parameters was systematically reviewed, and the methodological quality of these studies was analyzed. The Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines were followed, and the studies included were limited to those that evaluated changes in hematological tests in ectoparasite-infested and non-infested animals, and bias and methodological quality were evaluated using the Animal Research: Reporting of In Vivo Experiments guideline. Thirty-four studies were selected and information about the host, ectoparasite infestation, blood collection, and analysis was collected and compared whenever possible. In this review, the presence of ectoparasites influenced both the red series and the white series of hematological parameters. Among the main parameters analyzed, hematocrit, red blood cells, hemoglobin, and lymphocytes showed reductions, probably due to ectoparasite blood-feeding, while including eosinophils, neutrophils, and basophils increased in infested animals due to the host immune response. However, methodologic improvements are needed to reduce the risk of bias, enhance the reproducibility of such studies, and ensure results aligned with the mechanisms that act in the ectoparasite-host relationship.

Anti-Müllerian hormone (AMH) is a dimeric glycoprotein belonging to the superfamily of the transforming growth factor-β. Due to the discovery of AMH functions, relative to the ovarian function, it is being postulated as being a highly important marker in studies on mammalian reproduction. Therefore, the objective of this review was to describe the role of this hormone in different reproductive aspects of female mammals, taking women, cows, and mares as reference species. The relationship between ovarian reserve and AMH was analysed, and it has been verified that there is a relationship between the latter, the antral follicle count, and the number of primary follicles. AMH concentration has been associated with parameters like the age of the individual, fertility, superovulation treatments and embryo production, and to the reproductive hormone concentration. Also, an association between AMH and female reproduction system diseases, and the fact that AMH is a heritable feature in the cow have also been proven. Recent studies have analysed the role of AMH receptor type 2 since it appears that, together with gonadotropin-releasing hormone, it controls the secretion of gonadotropins. Despite the considerable amount of bibliography on AMH, more studies are needed to complete the information that we have on it, in order to reveal the unknown elements in its action mechanisms.

Calves sold at weaning are the main source of income for cow–calf operations, and their survival should be a priority. Given this, the effective use of management practices for pregnant dams and calves to prevent calf mortality is essential; however, decision-makers often do not have access to information about the effectiveness of many management practices. A systematic review was conducted to summarize the evidence of the effectiveness of biosecurity, vaccination, colostrum management, breeding and calving season management, and nutritional management practices for preventing preweaned beef calf mortality. The population of interest was preweaned beef calves from birth until at least 3 months of age. The outcome of interest was general preweaning calf mortality with stillbirths excluded. Eleven studies were deemed relevant. Ten were observational cross-sectional studies, and one was a randomized controlled trial (RCT). The practices that were statistically significantly associated with calf mortality were intervening with colostrum in case a calf had not nursed from its dam or was assisted at calving, timing and length of the calving season, and injecting selenium and vitamin E at birth. More well-executed RCTs and cohort studies are needed to provide evidence of effectiveness and help support implementation of recommended practices in herds.

Atypical porcine pestivirus (APPeV) is a pestivirus affecting pigs, notably causing high mortality in piglets due to neurological issues that impair suckling. This study reviews global literature from 2015 to March 2024, assessing APPeV prevalence. Analysing 40 relevant articles, it finds APPeV widely distributed across Europe, South America, North America, and Asia, with minimal presence in Africa and Australia. The scarcity in these regions might be due to geographical isolation, environmental factors, limited surveillance, diagnostics, or under-reporting. China leads in APPeV prevalence reports, followed by the USA, Germany, Sweden, and other countries. The main diagnostic methods are quantitative reverse transcription polymerase chain reaction (RT-qPCR) and RT-PCR, using tissue and serum samples. APPeV detection in the serum of boars and wild boars suggests possible persistent infections, indicating their role in APPeV epidemiology. Given the global outbreaks, particularly of congenital tremor (CT), the study calls for expanded research, especially in under-studied regions like Africa and Australia, focusing on healthy pigs, CT-affected piglets, and boars to better understand APPeV transmission dynamics.