Inter-breed diversity and temporal dynamics of the faecal microbiota in healthy horses

Understanding gut microbiota similarities and differences across breeds in horses has the potential to advance approaches aimed at personalized microbial modifications, particularly those involved in improving sport athletic performance. Here, we explore whether faecal microbiota composition based on faecal 16S ribosomal RNA gene sequencing varies across six different sport breeds at two time points 8 months apart within a cohort of 189 healthy horses cared for under similar conditions. Lusitano horses presented the smallest and Hanoverians the greatest bacterial diversity. We found subtle but significant differences in β-diversity between Lusitano, Anglo Arabian and the central European breeds, and we reproduced these results across the two time points. Repeat sampling of subjects showed community to be temporally more stable in Lusitano and Anglo Arabian breeds. Additionally, we found that 27 genera significantly varied in abundance across breeds. Overall, 33% of these taxa overlapped with previously identified taxa that were associated with genetic variation in humans or other species. However, a non-significant correlation was observed between microbial composition and the host pedigree-based kinship. Despite a notable variation in the diversity and composition of the faecal microbiota, breed exerted limited effects on the equine faecal microbiota.     

Equine faecal microbiota transplant: Current knowledge,proposed guidelines and future directions

While certainly not a novel concept, faecal microbiota transplant (FMT) has recently garnered renewed interest in veterinary medicine due to its remarkable success in treating recurrent Clostridium difficile infection (CDI) in man. There is a dearth of information on indications and efficacy of FMT for the treatment of gastrointestinal disorders in the horse; however, based on evidence in man and other veterinary species, and anecdotal reports in horses, FMT may be a useful treatment for selected cases of acute and chronic diarrhoea and inflammatory bowel disease (IBD) in the horse. In the absence of evidence, expert opinion is offered on case selection and FMT procedure. More research is needed to explore the efficacy, indications and optimal preparation, storage and delivery of FMT to horses.     

Effects of Supplementing a Basal Diet of Chloris gayana Hay with One of Three Protein-rich Legume Hays of Cassia rotundifolia,Lablab purpureus and Macroptilium atropurpureum Forage on Some Nutritional Parameters in Goats

Growth and digestibility experiments were conducted on growing East African type goats offered Chloris gayana hay supplemented with one of three high-protein (119–128 g CP/kg DM) legume hays, Cassia rotundifolia (cassia), Lablab purpureus (lablab) or Macroptilium atropurpureum (siratro), and crushed maize to investigate the feed intake, digestibility, growth and urinary excretion of purine derivatives. Goats in the supplemented groups had higher total dry matter and nitrogen intakes and higher N retention and body mass gains than unsupplemented counterparts. The digestibility of dry matter, organic matter and neutral detergent fibre were increased by protein supplementation. Animals on supplemented diets had higher fractional outflow rates of particulate matter from the rumen. The production of protein by ruminal microbes and the efficiency of microbial N production were increased by supplementation. It was concluded that a mixture of low-quality grass hay (61.9 CP/kg DM) and either cassia, lablab or siratro hay, and maize grain can provide a productive balanced diet for growing goats.     

饲用型小黑麦遗传图谱构建及草产量相关性状QTLs初步定位

本研究以饲用型小黑麦杂交F₂代为作图群体,利用ISSR分子标记构建了遗传连锁图谱,并对小黑麦草产量相关性状（株高,分蘖数,单株生物量）进行了QTLs定位,可为小黑麦草产量相关主效QTL挖掘、功能基因定位以及分子标记辅助育种奠定基础。结果表明：521个F₂代单株草产量相关性状的田间表型数据呈连续变异,分布频率大致接近正态分布,可用于QTLs定位。该遗传图谱包含7个连锁群,图谱总长度为542.9 cM,标记间平均距离为5.90 cM,共有92个位点。对草产量相关性状基因进行QTL定位分析,共检测到17个QTLs,分布在6个连锁群上,控制株高的QTLs有5个,贡献率为6.7%~13.2%;控制分蘖数的QTLs有7个,贡献率为5.4%~15.4%;控制单株生物量的QTLs有5个,贡献率为7.4%~12.4%。其中QPH7-2,QNT2-2和QBS2分别对小黑麦株高、分蘖数和单株生物量的贡献率最大,为主效QTLs,可对其进行进一步克隆、转化及利用。     

Molecular diversity of the equine caecal microbiota and its correlation to postprandial fermentation metabolites: A preliminary approach

Abstract

In this work we address the short-term postprandial dynamic changes in the equine caecal microbial composition and the microbial fermentation metabolites in the caecum. Samples were collected every half hour for 8.5 hours postfeeding from two horses on two consecutive days. The caecal content of volatile fatty acids (VFAs), lactate, and ammonia (NH₃N), as well as microbiota composition and pH were analyzed. Mixed Sangers sequences generated from universal polymerase chain reaction (PCR)-amplified 16S rRNA gene were used to analyze the microbiota composition. Three main phylogroups were identified and classified as Clostridium cluster XIVa, Clostridium cluster III, and lactic acid bacteria. Furthermore, we found that the composition of the caecal microbiota was closely associated with the VFA profile. Our main findings were that short-term microbial fluctuations occur in healthy hindgut fermenting horses as a response to feed intake.     

Effect of oral supplementation of probiotic strains of Lactobacillus rhamnosus and Enterococcus faecium on the composition of the faecal microbiota of foals

Effects of probiotics on the intestinal microbiota of foals are yet insufficiently studied. The aim of this study was to investigate whether supplementation of Lactobacillus rhamnosus (DSM 7133) and Enterococcus faecium (DSM 7134) influences the bacterial composition of the faecal microbiota of foals. A total of 34 newborn foals were randomly assigned to the placebo group (PG, n = 16) and the treatment group (TG, n = 18). From day 1 to day 14 of life, foals orally received 3 ml of either a probiotic preparation (1.05 × 10⁹ CFU E. faecium and 4.50 × 10⁸ CFU L. rhamnosus) or placebo (carrier) once a day. Faeces were collected directly from the rectum immediately after birth (meconium) and at day 14 and day 56 of life. Samples of 12 foals per group were selected for microbiological analysis. DNA was extracted and used for polymerase chain reaction–denaturing gradient gel electrophoresis (PCR‐DGGE) and quantitative PCR. No DNA or amplicons were obtained from meconium. There were no differences in richness of bands and Shannon index of diversity regarding the Clostridium cluster XIVa between groups. Cluster analysis and principal coordinate analysis of DGGE data showed a clear effect of age. Band‐based similarity of bacterial clusters (Dice coefficient) decreased from day 14 to day 56 of life (p < 0.001) in PG foals only resulting in lower similarity in PG versus TG foals when 2 month old (p < 0.01). Five of thirty re‐amplified bands were identified on species level. Others were assigned either to family (mainly Lachnospiraceae) or genus level (Akkermansia). The bands related to Akkermansia muciniphila or Akkermansia spp. appeared almost in all DGGE profiles. Two‐week supplementation of the probiotic preparation to foals had no significant impact on the composition of the faecal microbiota but it appears to have prevented the reduction of bacterial similarity between 2 and 8 weeks of age observed in not treated foals.     

The structure and regulation of the Irish equine industries: Links to considerations of equine welfare

The equine industries in Ireland are vibrant and growing. They are broadly classified into two sectors: Thoroughbred racing, and sports and leisure. This paper describes these sectors in terms of governance, education and training in equine welfare, and available data concerning horse numbers, identification, traceability and disposal. Animal welfare, and specifically equine welfare, has received increasing attention internationally. There is general acceptance of concepts such as animal needs and persons' responsibilities toward animals in their care, as expressed in the 'Five Freedoms'. As yet, little has been published on standards of equine welfare pertaining to Ireland, or on measures to address welfare issues here. This paper highlights the central role of horse identification and legal registration of ownership to safeguard the health and welfare of horses.     

Motility of the equine gastrointestinal tract: Physiology and pharmacotherapy

Normal gastrointestinal (GI) motility patterns are necessary to maintain transit of ingesta and to facilitate digestion and absorption of nutrients. Disorders of the equine GI tract are frequently encountered by the equine practitioner and these disorders are often associated with an interruption in normal intestinal motility patterns, thus complicating treatment of the primary disease. Consequently, numerous treatments have been investigated in horses to facilitate the return of normal intestinal motility. The purpose of this article is to provide a brief review of the anatomy and physiology of the GI tract in the horse and review medications available to the equine veterinarian that may potentially promote intestinal motility.     

不同施肥水平与组合对饲用黑麦生产性能的影响研究Ⅱ对饲用黑麦质量的影响

应用回归均匀设计构造试验方案,研究氮肥、磷肥、钾肥不同水平与组合对饲用黑麦干草质量的动态关系.结果表明,饲用黑麦干草中粗蛋白质(CP)含量主要受施氮水平的影响,受磷、钾施肥水平的影响很小;饲用黑麦干草中性洗涤纤维(NDF)含量、酸性洗涤纤维(ADF)含量不仅受施氮水平的影响,同时也受磷、钾施肥水平的影响;饲草质量随施氮水平的增加而增加,随磷、钾肥施入水平的增加而降低,总体而言,施肥量特别是氮肥施入量对饲用黑麦干草品质有较大影响.在试验范围内,为了获得较高的饲用黑麦干草质量(CP>14%),氮肥(N)施量不应低于226.5 kg/hm2, P2O5、K2O应少施为好.     

Host genotype and amoxicillin administration affect the incidence of diarrhoea and faecal microbiota of weaned piglets during a natural multiresistant ETEC infection

Enterotoxigenic Escherichia coli (ETEC) is the aetiological agent of postweaning diarrhoea (PWD) in piglets. The SNPs located on the Mucine 4 (MUC4) and Fucosyltransferase 1 (FUT1) genes have been associated with the susceptibility to ETEC F4 and ETEC F18, respectively. The interplay between the MUC4 and FUT1 genotypes to ETEC infection and the use of amoxicillin in modifying the intestinal microbiota during a natural infection by multiresistant ETEC strains have never been investigated. The aim of this study was to evaluate the effects of the MUC4 and FUT1 genotypes and the administration of amoxicillin through different routes on the presence of diarrhoea and the faecal microbiota composition in piglets naturally infected with ETEC. Seventy-one piglets were divided into three groups: two groups differing by amoxicillin administration routes—parenteral (P) or oral (O) and a control group without antibiotics (C). Faecal scores, body weight, presence of ETEC F4 and F18 were investigated 4 days after the arrival in the facility (T0), at the end of the amoxicillin administration (T1) and after the withdrawal period (T2). The faecal bacteria composition was assessed by sequencing the 16S rRNA gene. We described that MUC4 and FUT1 genotypes were associated with the presence of ETEC F4 and ETEC F18. The faecal microbiota was influenced by the MUC4 genotypes at T0. We found the oral administration to be associated with the presence of diarrhoea at T1 and T2. Furthermore, the exposure to amoxicillin resulted in significant alterations of the faecal microbiota. Overall, MUC4 and FUT1 were confirmed as genetic markers for the susceptibility to ETEC infections in pigs. Moreover, our data highlight that group amoxicillin treatment may produce adverse outcomes on pig health in course of multiresistant ETEC infection. Therefore, alternative control measures able to maintain a healthy faecal microbiota in weaners are recommended.     

Ultrasound-guided injections of the equine head and neck: review and expert opinion

Ultrasound-guided injections can be used for a wide variety of conditions in the horse, including both diagnostic and therapeutic applications. Benefits of ultrasound guidance include more accurate deposition of injectate compared with blind approaches. Improved identification of vital structures, including nerves and blood vessels, allows their avoidance and thus reduces procedure-associated complications. Validation of such ultrasound-guided techniques has shown that they can be easily learnt by inexperienced veterinarians, assuming a proper knowledge of the sonographic anatomy. In many cases they can be employed in the field with a high level of accuracy, using widely available equipment, and with complete adherence to the sterility principles. Many ultrasound-guided injection techniques of the axial skeleton in the horse have been described in past years, enabling the equine veterinarian to perform more accurate treatments of specific anatomical areas. The goal of this review is to discuss diagnostic and therapeutic ultrasound-guided injection techniques of the skull and cervical spine in the horse, including those for the retrobulbar space, maxillary and inferior alveolar nerves, atlanto-occipital and atlanto-axial junctions, and cervical articular process joints, as well as the 1st cervical nerve, the C2 and C3 nerve plexus, and the 6th, 7th, and 8th cervical nerve roots.     

Radiographic and scintigraphic evaluation of spondylosis in the equine thoracolumbar spine: A retrospective study

Reasons for performing study: Clinical, radiographic and scintigraphic signs associated with spondylosis of the equine thoracolumbar spine have been poorly documented. Objectives: To establish an objective radiographic and scintigraphic grading system for spondylosis lesions; to estimate the prevalence of spondylosis in a population of horses with back pain; and to compare the results of radiography and scintigraphy Methods: Radiographic images of the thoracolumbar spine from 670 horses with clinical signs of back pain were graded. Scintigraphic images from horses with spondylosis lesions underwent subjective and objective analysis. Sensitivity and specificity of scintigraphy for detection of spondylosis relative to radiography for identification of spondylosis were calculated, and Chi‐squared analysis was performed to test for an association between location and severity of lesions. Results: Twenty‐three of 670 horses (3.4%) with back pain had radiographic evidence of spondylosis. Of these horses, 14 (61%) had more than one lesion and 44% (n = 22) of lesions occurred between T11‐T13 vertebral bodies. Only 33% (n = 28) of locations with radiographic changes had increased radiopharmaceutical uptake. Conclusion: Spondylosis occurs at a low prevalence in horses with back pain. It may be present alone or in association with other osseous abnormalities. The clinical significance of spondylosis needs further investigation. Potential relevance: Spondylosis is uncommon but may be a contributor to back pain in the horse.