Animal Frontiers最新文献

{"title":"Antibiotics shape microbiota and weight gain across the animal kingdom","authors":"Laura M. Cox","doi":"10.2527/AF.2016-0028","DOIUrl":"https://doi.org/10.2527/AF.2016-0028","url":null,"abstract":"Shortly after the discovery of antibiotics and their successful application to treat infectious diseases, researchers discovered the growth-promoting capacity of sub-therapeutic antibiotic treatment (Jukes and Williams, 1953; Taylor and Gordon, 1955; Dubos et al., 1963). For more than 60 yr, sub-therapeutic antibiotic treatment has been shown to increase growth rate and weight gain in a wide variety of livestock, including chickens, pigs, cows, and sheep, indicating an evolutionarily conserved relationship between microbes and host metabolism. Because of the high cost of antibiotics at the time of initial discovery (Cromwell, 2002), antibiotics were provided low levels in the animal feed. This economically constrained dosage choice turned out to be a fortunate one, since later studies demonstrated that highdose antibiotic treatment could lead to reduced weight gain or weight loss (Dubos et al., 1963; Carvalho et al., 2012). Many classes of antibiotics are efficacious for growth promotion, including those used to treat human diseases and categorized by the FDA as highly important or critically important for human health, such as b-lactams, macrolides, lincosamides, and tetracyclines (Apley et al., 2012), although the specific antibiotic within the class may differ for human vs. animal use (e.g., azithromycin is a macrolide used for humans, and tylosin a veterinary macrolide). While many antibiotics have been banned in Europe for decades (Millet and Maertens, 2011), their use is only recently being phased out in the United States in response to FDA guidance for a voluntary withdrawal. The antimicrobial dose for growth promotion is often one to two orders of magnitude lower than for therapeutic applications (Apley et al., 2012; Subbiah et al., 2016) and does not have the primary goal of treating disease or preventing infection (Allen and Stanton, 2014). For example, chlortetracycline would be administered at 70 mg/animal/day for growth promotion, at 350 mg/animal/day to for prophylaxis against catching infection, and at 22 mg/kg body weight—approximately 6,600 mg/animal for a 300-kg steer (Cazer et al., 2014). The practice of using low-dose antibiotic growth promotion continues today around the world and is projected to increase in several countries (Van Boeckel et al., 2015). While it has economic benefits associated with increasing weight gain and feed efficiency (the conversion of food to animal mass), results can vary across production facilities, and there is growing evidence and concerns that widespread use of low-dose antibiotics increases the selection for antibiotic-resistant bacteria and their transmission to the human population (Allen et al., 2013). In recent years, there has been both legislative actions and consumer pressure to reduce or eliminate the use of antibiotics for growth promotion (Borron, 2012; Antibiotics shape microbiota and weight gain across the animal kingdom","PeriodicalId":48645,"journal":{"name":"Animal Frontiers","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2016-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2527/AF.2016-0028","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68979527","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Methane matters: from blue-tinged moos, to boozy roos, and the health of humans too","authors":"E. Hoedt, P. Ó. Cuív, M. Morrison","doi":"10.2527/AF.2016-0029","DOIUrl":"https://doi.org/10.2527/AF.2016-0029","url":null,"abstract":"• Methane emissions from ruminant livestock are proposed to contribute ~10 to 20% of annual global greenhouse gas emissions. • Recent efforts have shown that \"low methane emitting\" animals can be identified both within and across species, including nondomesticated herbivores. • Methanogens are also present within the human gut and some other body sites, and variations in their diversity and/or abundance has been linked to some functional gastrointestinal disorders and non-communicable chronic diseases. • Recent advances in \"-omics\" technologies have provided new insights of the roles that methanogens play in both feed digestion and host-microbe interactions. • Although much research and understanding has been derived from the study of the numerically dominant Methanobrevibacter genus, the recent studies outlined above have shown that other, \"heterotrophic\" methanogens warrant greater attention. • Here, we provide a brief overview of our recent research of the Methanosphaera genus and outline the possible consequences associated with its presence in the gut of livestock, native Australian herbivores, and humans.","PeriodicalId":48645,"journal":{"name":"Animal Frontiers","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2016-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2527/AF.2016-0029","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68979556","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Gut microbiota, diet, and health: Application to livestock and companion animals","authors":"K. Swanson","doi":"10.2527/AF.2016-0027","DOIUrl":"https://doi.org/10.2527/AF.2016-0027","url":null,"abstract":"","PeriodicalId":48645,"journal":{"name":"Animal Frontiers","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2016-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2527/AF.2016-0027","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68979517","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Role of the gut microbiota in equine health and disease","authors":"E. Venable, S. Bland, J. L. McPherson, J. Francis","doi":"10.2527/AF.2016-0033","DOIUrl":"https://doi.org/10.2527/AF.2016-0033","url":null,"abstract":"","PeriodicalId":48645,"journal":{"name":"Animal Frontiers","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2016-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2527/AF.2016-0033","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68979492","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Importance of gut microbiota for the health and disease of dogs and cats","authors":"Amanda B Blake, J. Suchodolski","doi":"10.2527/AF.2016-0032","DOIUrl":"https://doi.org/10.2527/AF.2016-0032","url":null,"abstract":"","PeriodicalId":48645,"journal":{"name":"Animal Frontiers","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2016-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2527/AF.2016-0032","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68979409","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The role of gut microbiota in the health and disease of pigs","authors":"J. Fouhse, R. Zijlstra, B. Willing","doi":"10.2527/AF.2016-0031","DOIUrl":"https://doi.org/10.2527/AF.2016-0031","url":null,"abstract":"The pig intestine is home to a dynamic microbial population that forms a complex ecosystem and has a symbiotic relationship with the host. The population of gut microbes, or microbiota, plays key roles in maintaining nutritional, physiological, and immunological functions of the pig (Lee and Mazmanian, 2010; Brestoff and Artis, 2013). However, this microbial population also includes disease-causing organisms such as Escherichia coli, Salmonella, and Clostridia. These pathogenic organisms can cause substantial morbidity and mortality; thus, prophylactic use of antibiotics has been common in livestock industries. Disturbances in the gut microbial ecosystem during the rearing of pigs can dramatically increase risk of disease. To meet production goals in the swine industry, piglets are weaned early, before a stable microbial population is established and the immune system is mature. Stress at weaning further disrupts the gut microbial ecosystem (Konstantinov et al., 2006), increasing susceptibility to bacterial post-weaning diarrhea (Lallès et al., 2004). The use of prophylactic antibiotics tends to balance these disturbances, decreasing incidence of gastrointestinal disease, particularly at weaning. Widespread use of prophylactic and growth-promoting antibiotics has increased selective pressure for anti-microbial resistant bacteria and is now a major public health concern (Dibner and Richards, 2005). Using current knowledge of the host–microbial relationship, strategies including the use of prebiotics, highly fermentable carbohydrate cereal grains, probiotics, and (or) microbial transplants may promote animal health and reduce the need for antibiotic use. However, future research must quantitatively and qualitatively define the composition and function of a ‘healthy’ pig gut microbiota to successfully implement such strategies.","PeriodicalId":48645,"journal":{"name":"Animal Frontiers","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2016-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2527/AF.2016-0031","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68979235","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dietary impacts on rumen microbiota in beef and dairy production","authors":"J. Loor, A. Elolimy, J. McCann","doi":"10.2527/AF.2016-0030","DOIUrl":"https://doi.org/10.2527/AF.2016-0030","url":null,"abstract":"The reticulo-rumen is the largest compartment of the ruminant digestive tract, and it harbors a complex anaerobic microbial community capable of producing a wide array of enzymes, some of which are important for the breakdown of plant lignocellulosic and non-structural carbohydrate (starch, sugars) material through the process of fermentation (Russell and Rychlik, 2001). Important outcomes of microbial fermentation are the production of volatile fatty acids (or short-chain fatty acids) that serve as fuels for the animal’s tissues and the synthesis of microbial protein that provides amino acids for the animal to produce high-quality protein for human consumption, i.e., meat and milk. Studies over the last few decades have conclusively demonstrated that the ruminal microbial ecosystem (both of the neonate and mature ruminant) can be altered by nutritional management (McCann et al., 2014b). Therefore, nutrition represents an important tool for manipulating the microbial ecosystem to optimize rumen function while producing high-quality meat and milk for meeting the demands of a growing human population. The recent development of omic technologies, e.g., sequencing of the 16S and 18S ribosomal RNA gene, metagenomics, and metatranscriptomics, along with bioinformatics tools, have not only enhanced the understanding of the rumen ecology, but also our ability to predict the functional capacity of the microbiota (McCann et al., 2014b). From a production standpoint, it is believed that further gains in knowledge that in the medium-to-long term could lead to practical applications will arise from the integration of taxonomic and functional data with “classical” parameters of rumen digestion, metabolism, and performance (Morgavi et al., 2013). Our aim in this review is to provide recent examples demonstrating how nutrition can alter the structure, composition, and diversity of the rumen microbiota in beef and dairy production. In addition, we attempt to highlight points where there are knowledge gaps for further research.","PeriodicalId":48645,"journal":{"name":"Animal Frontiers","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2016-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2527/AF.2016-0030","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68979621","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Gut microbiome and omics: a new definition to ruminant production and health","authors":"N. Malmuthuge, L. Guan","doi":"10.2527/AF.2016-0017","DOIUrl":"https://doi.org/10.2527/AF.2016-0017","url":null,"abstract":"","PeriodicalId":48645,"journal":{"name":"Animal Frontiers","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2016-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2527/AF.2016-0017","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68978992","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The importance of microbiota in ruminant production","authors":"T. Alexander, J. Plaizier","doi":"10.2527/AF.2016-0016","DOIUrl":"https://doi.org/10.2527/AF.2016-0016","url":null,"abstract":"","PeriodicalId":48645,"journal":{"name":"Animal Frontiers","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2016-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2527/AF.2016-0016","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68978485","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modifying gut microbiomes in large ruminants: Opportunities in non-intensive husbandry systems","authors":"M. Wadhwa, M. Bakshi, H. Makkar","doi":"10.2527/AF.2016-0020","DOIUrl":"https://doi.org/10.2527/AF.2016-0020","url":null,"abstract":"","PeriodicalId":48645,"journal":{"name":"Animal Frontiers","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2016-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2527/AF.2016-0020","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68978831","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}