A respirometry system designed for small ruminants

Abstract

This technical note describes a small ruminant respiration chamber system designed to accurately quantify the production of carbon dioxide (CO₂) and methane (CH₄). The system consists of 3 open-circuit respiration chambers, flow meters, gas analyzers, and an accessible environmental control system. To validate its performance, gas recovery tests were conducted by injecting CO₂ and CH₄ at 4 constant flow rates: 0.4, 0.8, 1.2, and 1.6 standard liters per minute (SLPM) for CO₂, and 0.16, 0.20, 0.24, and 0.28 SLPM for CH₄. Each injection level was tested across the 3 chambers. The average percentage recoveries for CO₂ and CH₄ were 97.8% ± 1.46% for chamber 1, 101.1% ± 1.49% for chamber 2, and 104.1% ± 1.98% for chamber 3 and 98.7% ± 0.97% for chamber 1, 99.4% ± 2.06% for chamber 2, and 101.6% ± 2.90% for chamber 3, respectively, demonstrating the system's accuracy in quantifying livestock GHG emissions from small ruminants, such as young cattle, goats, and sheep. Therefore, this system represents a viable methodology for nutritional and environmental studies with small ruminants. Future studies conducted in this facility can contribute to a better understanding of the dynamic and flow of GHG emissions in small ruminants and target measures to increase the sustainability of small ruminant production systems.