Rumen and Abomasal Cannulation of Sheep with Specially Designed Cannulas and a Cannula Insertion Instrument

Abstract

Rumen and abomasal cannulas for sheep and an instrument that facilitates rapid insertion of the cannulas were developed. The cannulas were made from epoxy-filled polyurethane and were supported by outer support rings held in place by nuts screwed onto the threaded tops of the cannula barrels. The insertion device was used to pull the cannula through a separately made incision in the abdominal wall and to stretch the skin and other tissues over a cone and onto the barrel of the cannula, thus ensuring a tight fit and the formation of a ring of scar tissue that virtually eliminated digesta leakage. Expansion plugs, used to seal the cannulas, were designed to eliminate a twisting force that could be transferred to the cannula when the plugs were secured or released. The plugs were also designed to protrude minimally from the side of the animal. More than 75 sheep were cannulated, and the preparations proved to be relatively maintenance free and resistant to mechanical disturbance by the animal. The cannulas had a long functional life and permitted convenient sampling of digesta and introduction of liquid and solid materials, including digestion bags.

Design, implementation and interpretation of in vitro batch culture experiments to assess enteric methane mitigation in ruminants—a review

“…Rumen cannulation is considered the reference method allowing the collection of representative samples of rumen digesta from donor animals (Komarek, 1981;Kristensen et al, 2010). Access to surgically-modified animals is not universal, and therefore less invasive techniques, such as oral stomach probing, have been used as an alternative.…”

Fistulation and Cannulation of the Rumen in Buffaloes: Comparision of Two Methods

“…There are various complications associated with rumen fistulation and canulationis, like loosening of the cannula, increases in size of the fistula by necrosis of the tissue or ruminal fluid leak [6]. The leakage of large amounts of ruminal contents can take the animal to dehydration and malnutrition [4].…”

Técnica de fistulação e canulação do rúmen em bovinos e ovinos

“…Existe uma grande variedade de cânulas ruminais, podendo ser preparadas com material rígido, como metal, plástico ou acrílico; ou confeccionadas com material flexível, como borracha, silicone ou vinil. De forma geral, as cânulas fabricadas com material maleável são mais fáceis de serem implantadas e manipuladas (KOMAREK, 1981).…”

“…Pelo fato de os cordeiros terem sido operados em decúbito, a atropina foi administrada com o objetivo de reduzir a salivação e a motilidade do rúmen (KOMAREK, 1981). Deve-se ter cautela ao operar os ovinos em decúbito lateral, pois o rúmen exerce pressão sobre a cavidade abdominal, podendo alterar os planos anatômicos.…”