Heritability estimates and genome-wide association study of methane emission traits in Nellore cattle.

The objectives of the present study were to estimate the heritability for daily methane emission (CH4) and residual daily methane emission (CH4res) in Nellore cattle, as well as to perform genome-wide association studies (GWAS) to identify genomic regions and candidate genes influencing the genetic variation of CH4 and CH4res. Methane emission phenotypes of 743 Nellore animals belonging to 3 breeding programs were evaluated. CH4 was measured using the sulfur hexafluoride (SF6) tracer technique (which involves an SF6 permeation tube introduced into the rumen, and an appropriate apparatus on each animal), and CH4res was obtained as the difference between observed CH4 and CH4 adjusted for dry matter intake.

Tannin-based product in feedlot diet as a strategy to reduce enteric methane emissions of Nellore cattle finished under tropical conditions.

A total of 120 Nellore bulls, [initial body weight (BW) = 307 ± 11.6 kg and 12 mo of age] were allocated into 12 collective pens (10 bulls per pen) in a commercial feedlot to evaluate the effects of a specific blend of tannin and saponins on enteric methane (CH) emissions. The study was a completely randomized design, in which pens were considered the experimental units ( = 6 pens per treatment) and were randomly allocated into one of two treatments: 1) Control (CON), a basal diet with monensin supplementation (25 mg/kg dry matter [DM]; Rumensin, Elanco Animal Health, Greenfield, IN, USA), or 2) Control + a specific blend of tannin and saponins (TAN; 7 g/kg DM; composed of quebracho and chestnut tannin extracts along with carriers from cereals rich in saponins; SilvaFeed BX, Silvateam, San Michele Mondovi, CN, Italy).

Effects of Feeding and Drinking Behavior on Performance and Carcass Traits in Beef Cattle.

Feed and water efficiency are important traits to improve beef cattle production’s economic and environmental sustainability. This study evaluated residual feed intake (RFI) and residual water intake (RWI) and their relationship with performance, ingestive behavior, and carcass traits in Caracu beef cattle. The data were analyzed using a generalized linear model with least squares means.

Effect of Yerba Mate Extract as Feed Additive on Ruminal Fermentation and Methane Emissions in Beef Cattle.

The inclusion of plant extracts that contain secondary compounds with the potential to modulate rumen fermentation and improve animal performance has gained attention in recent years. The aim of this study was to evaluate the effect of the inclusion of yerba mate extract (Ilex paraguariensis ST. Hilaire) (YME) on the ruminal parameters.

Phenotypic association among performance, feed efficiency and methane emission traits in Nellore cattle.

Enteric methane (CH4) emissions are a natural process in ruminants and can result in up to 12% of energy losses. Hence, decreasing enteric CH4 production constitutes an important step towards improving the feed efficiency of Brazilian cattle herds. The aim of this study was to evaluate the relationship between performance, residual feed intake (RFI), and enteric CH4 emission in growing Nellore cattle (Bos indicus).

Genetic association among feeding behavior, feed efficiency, and growth traits in growing indicine cattle.

This study aimed to estimate genetic parameters, including genomic data, for feeding behavior, feed efficiency, and growth traits in Nellore cattle. The following feeding behavior traits were studied (861 animals with records): time spent at the feed bunk (TF), duration of one feeding event (FD), frequency of visits to the bunk (FF), feeding rate (FR), and dry matter intake (DMI) per visit (DMIv). The feed efficiency traits (1,543 animals with records) included residual feed intake (RFI), residual weight gain (RWG), and feed conversion (FC).

Pasture intensification in beef cattle production can affect methane emission intensity.

Increasing greenhouse gas (GHG) emissions from anthropogenic activities have contributed to global warming and consequently to climate change. Among all sources of emissions, the agricultural sector accounts for just under a quarter, mainly because of the intensification of food production systems necessary to supply the growing demand of the population. As ruminal fermentation is the largest source of methane emission in the livestock industry, emission by cattle has become the focus of studies.

Methane Emissions, Performance and Carcass Characteristics of Different Lines of Beef Steers Reared on Pasture and Finished in Feedlot.

The present study aimed to investigate whether different lines of a composite breed (5/8 Charolais × 3/8 Zebu), formed at different times, and genetically improved, would result in differences in animal performance, enteric methane emissions, and carcass traits. Forty-six Canchim steers (15 months, 280 ± 33 kg liveweight) from three different lines were used: old, new, and their cross. These three breed lines were considered the treatments (arranged in four randomized blocks based on initial liveweight) and were evaluated under grazing and feedlot conditions in relation to the performance and emission of enteric methane.

Evaluation of test duration for feed efficiency in growing beef cattle.

The aim of this study was to determine the shortest test duration necessary for the evaluation of feed efficiency traits, i.e., dry matter intake (DMI), average daily gain (ADG), mid-test metabolic body weight, residual feed intake (RFI), feed conversion ratio (DMI/ADG), and feed conversion efficiency (ADG/DMI).