Development of prediction models for quantification of total methane emission from enteric fermentation of young Holstein cattle at various ages

摘要: Abstract Methane (CH4) emissions from ruminant animals contribute significantly to the global greenhouse gas budget. The accurate quantification of this source requires detailed animal and feed information, however there is little information available on systematic measurement CH4 young cattle at various ages. present study was designed address gap knowledge. Data used were derived a with 20 Autumn-calved Holstein (10 steers 10 heifers) measured age 6, 12, 18 22 months, respectively. offered typical diet UK commercial farms containing single grass silage mixed concentrates. In each period, housed as group in cubicle accommodation for first days, individually metabolism units next 3 then indirect open-circuit respiration calorimeter chambers final 5 days intake, feces urine outputs gaseous exchange during 4 days. Within gender had no effect (P > 0.05) nutrient digestibility any emission variable terms total emission, proportion live weight or energy output intake. data two groups therefore pooled develop prediction equations daily (g day−1). A range have been developed using BW (body weight), intake also calculate accumulated genders. Although results, increased growth (mean 36.2 64.3 kg year−1 both genders years 1 2, respectively). number factors (kg year−1) heifers second year rearing. These very strongly related (r2 = 0.75–0.95) recorded beginning, middle end 2 age. can add novel scientific literature be improve national inventories appropriate mitigation strategies high genetic merit herds.