Preliminary results on the association with feeding and recovery length in equine colic patients after laparotomy

Microbiota characterization throughout the digestive tract of horses fed a high-fiber vs. a high-starch diet

Introduction

Diet is one of the main factors influencing the intestinal microbiota in horses, yet a systematic characterization of the microbiota along the length of the digestive tract in clinically healthy horses, homogenous for age and breed and receiving a specific diet is lacking.

Methods

The study used 16S rRNA amplicon sequencing to characterize the microbiota of the intestinal tracts of 19 healthy Bardigiano horses of 14.3  ±  0.7  months of age fed one of two diets. Nine horses received a high-starch diet (HS), and ten horses received a high-fiber diet (HF). After 129  days, the horses were slaughtered, and samples were collected from the different intestinal tract compartments.

Results and discussion

The microbiota alpha diversity indices were lower in the caecum, pelvic flexure and right dorsal colon of the horses fed the HS diet (False Discovery Rate, FDR  <  0.05). The values of beta diversity indicated significant compositional differences between the studied intestinal tract compartments according to the diet received (FDR  <  0.05). At the lower taxonomic level (genus or family), the HS diet was associated with a higher relative frequency of Enterobacteriaceae within the small intestine (jejunum and duodenum) (FDR  <  0.05). Within the hindgut (caecum and sternal flexure), the HS diet was associated with lower relative frequencies (i.e., a smaller core community) of bacteria belonging to Fibrobacteraceae and Prevotellaceae (FDR  <  0.05). Moreover, horses fed the HS diet displayed a higher relative abundance of Streptococcus in the caecum (FDR  <  0.05) and Fusobacterium in the sternal flexure (FDR  <  0.05), both of which are pathogenic bacteria responsible for inflammation diseases. Samples collected from the pelvic flexure and rectum of horses fed the HS diet showed significantly higher relative frequencies of Succinivibrionaceae (FDR  <  0.05) - amylolytic bacteria associated with acidosis. The relative frequencies of the Lachnospiraceae and Ruminococcaceae were lower in the feces collected from the rectum of horses receiving the HS diet vs. HF diet, indicating smaller core communities of these bacteria (FDR  <  0.05). Fibrous diets should be promoted to prevent dysbiosis of the microbiota associated with high-starch diet.

Scoping review: Occurrence and definitions of postoperative complications in equine colic surgery

BACKGROUND

Postoperative complications frequently occur following equine colic surgery but there is a lack of consistency in their definitions and reporting.

OBJECTIVES

To perform a scoping review to identify current evidence on the definitions and classifications of postoperative complications in equine colic surgery.

STUDY DESIGN

Evidence review.

METHODS

A scoping review was conducted in CAB, Web of Science, Scopus and PubMed databases using a PCC (Population-equids, Concept-complications, adverse events, sequelae, failure to cure, technical failure, disease progression and Context-postoperative period after colic surgery) search strategy. Peer-reviewed scientific articles in the English language on equine colic surgery in live client-owned equids between 1992 and 2022 were included. The resulting references were independently and blindly screened by two investigators. Relevant data on the study method, sample size, intestinal tract involvement and postoperative complications were extracted and charted.

RESULTS

Among 5850 articles potentially eligible, 272 met the final inclusion criteria. The most frequent types of study design were retrospective cohort studies (121/272) and retrospective case series (82/272). Median sample size was 53 animals, range 3-896. Seventy-nine of 272 (29%) studies reported diseases of the small intestine, 65 of 272 (24%) of the large intestine and 128 of 272 (47%) reported both. Seventy-two studies (26.4%) focused on single complications. No study explicitly defined the term complication or cited a classification of complications. One study reported the definitions of 'sequela', 'progression' or 'recurrence' of lesions. Eighty-one postoperative complications were reported in two-time frames defined as short- and long-term. The definitions of most complications and long-term follow-ups were highly variable.

MAIN LIMITATION

Non-English language studies or conference proceedings were excluded.

CONCLUSION

There was a substantial lack of classifications of postoperative complications. The definitions of complications were highly variable, making it difficult to compare studies. Adopting classification systems and definitions may help surgeons to obtain a complete picture of the efficacy of a procedure or treatment and allow comparisons between studies, centres or time periods.

Comparison of liberal and goal-directed fluid therapy after small intestinal surgery for strangulating lesions in horses

BACKGROUND

There are few guidelines for the appropriate mode of fluid administration during and after colic surgery, and is challenging to reach the right balance while avoiding overhydration. This study aimed to compare goal-directed fluid therapy (GDFT) and 'liberal' fluid regimens (LFRs) in horses undergoing small intestinal surgery.

METHODS

Eighteen horses subjected to small intestinal surgery were matched according to the surgical lesion, type of anastomosis, length of resection, and duration of clinical signs. Horses in the LFR group were administered intravenous (IV) fluids for at least 24 h. In the GDFT group, IV fluids were administered only when considered necessary based on clinical parameters. Postoperative reflux (POR), packed cell volume, total protein, heart rate, venous lactate level, complications, and long-term survival rates were compared.

RESULTS

Three horses in the LFR and one in the GDFT group developed POR. Horses in the GDFT group had a shorter time interval to first oral water intake and shorter hospitalisation time. Postoperative complication rates and survival were not different between groups.

CONCLUSION

Further studies are necessary to set guidelines for the evaluation of hydration status and to plan postoperative fluid administration; however, GDFT may be a valid alternative to liberal fluid therapy after colic surgery.

Equine nutrition in the post-operative colic: Survey of Diplomates of the American Colleges of Veterinary Internal Medicine and Veterinary Surgeons, and European Colleges of Equine Internal Medicine and Veterinary Surgeons

Background

Evidence is lacking concerning re‐introduction of feed and water following colic surgery.

Objectives

To describe current approaches of European and American specialists to re‐introduction of feed and water in adult horses following surgical treatment of common intestinal lesions, assuming an uncomplicated recovery.

Study design

Cross‐sectional survey.

Methods

Electronic invitations, with a link to the online survey, were sent to 1,430 large animal specialists, including Diplomates of the ECVS, ACVS, ECEIM and ACVIM colleges.

Results

The response rate was 12.6% including partial respondent data. Responses for each multiple‐choice question were between 123 and 178. Results are expressed as the percentage of the total number of responses and as a range where specific lesions are grouped together. Respondents reported that horses with large intestinal displacements were offered free choice water (63%‐65%) within 3 hours (55%‐63%), whereas horses with a small intestinal strangulating lesion were offered < 2 L water (64%‐74%) 12‐24 hours (28%‐34%) post‐operatively. Horses with a large colon displacement were offered feed within 3 hours of surgery (16%) with the majority offered feed 6‐12 hours (35%‐36%) post‐operatively. Horses with small intestinal strangulating lesions and small colon lesions were offered feed 24‐48 hours (34%‐42%) after surgery. Following small intestinal, small colon or caecal lesions, horses were re‐introduced feed in handfuls (79%‐93%) and initially with grass (41%‐54%). Horses with large colon displacements were mostly fed handfuls (49%‐50%) of forage initially, but a number of respondents would offer larger quantities such as a small bucket (35%‐37%) and predominantly of hay (50%‐51%).

Main limitations

Low response rate. This study did not take into account common post‐operative complications that may alter the clinical approach.

Conclusions

This post‐operative colic nutrition survey is the first to describe current clinical practice. Further research is required to investigate nutritional strategies in post‐operative colic cases.