We describe a novel surgical method for catheterizing ‘intestinal loops’ within the ileum of sheep. Once animals have recovered from surgery and have cleared antibiotics and analgesics, multiple treatments can be deposited directly in loops via the catheters.
Experimental procedure:
Critical points:
Procedures of crucial importance to the success of this surgical procedure include: (1) verifying that the intestine is not twisted on itself before establishing the anastomosis; (2) ensuring the integrity and patency of the anastomosis; (3) adequately securing the catheter to the loop wall with the ligature delineating the cranial end of the loop, but ensuring that the attachment does not affect the patency of the catheter; (4) minimizing intestinal handling and ensuring that exteriorized intestine is kept moist; (5) ensuring the appropriate catheter tension; (6) ensuring that the integrity of the catheter is not affected during muscle and skin suturing; (7) preventing gorging by sheep post-surgery (i.e. during the period of post-operative ileus) which can cause ruminal impaction and impairment of rumen function; and (8) ensuring that animals receive sufficient intravenous fluid therapy for the first 3-5 days post-surgery, that blood glucose concentrations are carefully monitored, and glucose concentrations in the intravenous fluids are adjusted if necessary to prevent hypoglycemia.
Figure 1. A schematic representation of catheterized ileal loops. Note the three 15 cm-long catheterized ‘loops’, the two 15 cm-long non-catheterized ‘interspaces’ established between the loops, and the two 5 cm-long terminal segments, all established within an 85 cm-long ‘intestinal segment’ of a sheep ileum.
In this procedure, we were able to successfully establish catheters in intestinal loops established within the ileum of sheep. By adhering to stringent post-operative care, animals rapidly recovered from the procedure and resumed normal activity 5-7 days after surgery. We determined that the establishment of catheters within loops does not affect intestinal mucosal or immune function (data not shown) and animals can live for at least 8 wk after surgery. This procedure allows us to introduce multiple treatments into distinct immunological compartments over an extended interval, once animals have recovered from surgery, and to empirically measure the physiological and immunological effects of these treatments.
An important consideration for future experiments is the location of the intestinal segment within the small intestine. In this procedure we surgically created the intestinal segment within the ‘immunologically functional ileum’ as often defined by ileal (continuous) Peyer’s patches (5,6). This area can extend cranially up to 2 m beyond ileocecal fold. Although this region is considered anatomically as the jejunum, in the context of immunological function, it is ileum, highlighting the importance of considering function when describing intestinal regions.
The authors have nothing to disclose.
The research could not have been completed without the dedication and efforts of many persons at the Agriculture and Agri-Food Canada Research Centre, Lethbridge, Alberta, Canada. In that regard, we thank: Tara Shelton for pre- and post-operative care of animals, surgical preparation, and anesthesiology, analysis of samples, and assistance with video imaging; Randy Wilde and Estela Costa for pre- and post-operative care; Jenny Gusse for sample analysis; Byron Lee for the trocar image; and Brian Egland for sheep husbandry. We also thank Brent Selinger (Department of Biological Sciences, University of Lethbridge) for providing video equipment and advice, as well as other assistance (i.e. executive production), and the Curriculum Re-Development Centre, University of Lethbridge for videography expertise. This study was supported in part by grants from the Advanced Foods and Materials Network (G.D.I.), the Canada-Alberta Beef Industry Development Fund (G.D.I.), and Agriculture and Agri-Food Canada (G.D.I. and J.P.K.).
Category / Item Number | Company | Catalogue |
Surgeon supplies | ||
Surgical gloves | WDDCa | 103091 |
Surgical mask | WDDC | MAX53013 |
Surgical gown | CDMVb | 3365 |
OB Apron | WDDC | 900062 |
Surgical cap | WDDC | 903271 |
EZ Scrub brush | WDDC | BDC377479 |
Anesthesia and drugs | ||
Anesthetic machine | Boyle | — |
Sodasorb | WDDC | 108638 |
Laryngoscope | WDDC | — |
Laryngoscope blade (Miller blade #4) | WDDC | 902667 |
Endotracheal tube (7.0 – 8.5 mm) | WDDC | — |
Lidocaine endotracheal spray | WDDC | 103364 |
Acepromazine | WDDC | AUS01020 |
Glycopyrrolate | WDDC | SAB2880 |
Butorphanol tartrate | WDDC | AYE304541 |
Diazepam | WDDC | sab790 |
Thiopental sodium | WDDC | 103508 |
Epinephrine hydrochloride | WDDC | 103856 |
Doxapram | Strathcona Pharmacy | — |
Isoflurane | WDDC | 100339 |
Hemostam | WDDC | 103857 |
Flunixin | WDDC | sch140100 |
Enrofloxacin | WDDC | hll0049 |
Metronidazole | WDDC | 101653 |
Ampicillin | WDDC | NOV67185-6 |
Cefazolin | WDDC | nov69397 |
Surgical equipment and supplies | ||
Electroscapel | Macan | MV8 |
Heating mat | Kane | PHMD-48 |
Stomach tube (Nalgene tubing 5/16″ ID) | Fisher Scientific | — |
Needle driver | WDDC | 108338 |
Addison brown forcep | WDDC | 911075 |
Rat tooth forcep | CDMV | 5275 |
Kelly forcep | WDDC | 901133 |
Mosquito hemostat | WDDC | 108471 |
Carmalt forcep | WDDC | 901225 |
Scalpel handle | WDDC | 900285 |
Scalpel blade #22 | WDDC | 900511 |
Metzenbaum scissor | WDDC | 901166 |
Sharp-sharp scissor | WDDC | 108264 |
Towel clamp | WDDC | 901213 |
Allis tissue forcep | WDDC | 901201 |
Doyen’s forcep | WDDC | 904226 |
Stainless steel bowl | WDDC | 903601 |
Stainless steel trocar (curved) | Local supplier | — |
Catheter introducer | WDDC | 11440 |
Surgical towel | CDMV | 7972 |
Disposable drape | WDDC | 900035 |
Steri drape | CDMV | 2323 |
Drape (40 x 40 cm) | CDMV | 8358 |
Surgical drape (7″ x 11 ¼” opening) | CDMV | 2694 |
Vicryl (2-0) | WDDC | JJMJ333H |
Silk 2-0 | WDDC | 105248 |
Catgut #3 | WDDC | CSL547-2070 |
Supramid #1 | WDDC | CSL547-3040 |
Needles (cutting and non-cutting) | WDDC | — |
Catheter | ||
Silastic tubing (0.040″ ID, 0.085″ OD) | Fisher Scientific | 11-189-15D |
Orbeseal ointment | WDDC | 106344 |
Clear silicone (732 multi-purpose sealant) | Local supplier | — |
Blunt end needle | WDDC | 905035 |
Marker (permanent industrial) | Local supplier | — |
Catheter pouch (constructed of Elastoplast 7.5 cm) | WDDC | 104094 |
Bandages | ||
Hospital tape (2″) | WDDC | 103842 |
Hospital tape (1″) | WDDC | VLMRENF20 |
Gauze sponge 4×4 | WDDC | 107551 |
Gauze cling | WDDC | 107633 |
Elastoplast 7.5cm | WDDC | 104094 |
Elastoplast rippable bandage | WDDC | 104093 |
Needles and syringes | ||
Syringe (60 ml) | WDDC | 104004 |
Syringe (10 ml) | WDDC | bdc301604 |
25G Needle | WDDC | BDC305122 |
20G Needle | WDDC | BDC305175 |
18G Needle | WDDC | 903353 |
Intravenous | ||
Intracath IV catheter (16G 8″) | WDDC | bdc3831621 |
IV administration set (10 drop) | WDDC | 101797 |
0.9% NaCl solution | WDDC | BAXJB1322P |
Plasmalyte 148 solution | WDDC | BAXJB2534 |
Dextrose | WDDC | MCT60190 |
Peristaltic pump | Cole Parmer | 7524-10 |
Livestock identification tag cement | Local supplier | — |
Sanatizers / disinfectants | ||
Germex solution | WDDC | mtc60270 |
Isopropyl alcohol | WDDC | 104590 |
Stanhexidine cleanser | WDDC | 109248 |
Prepodyne solution | WDDC | 105710 |
Prepodyne scrub | WDDC | 105711 |
aWestern Drug Distribution Center LTD, Edmonton, AB.
bThe Veterinary Medication Distribution Center Inc., St. Hyacinthe, QE.