Effect of refined soy oil or whole soybeans on intake, methane output, and performance of young bulls1

Abstract

An experiment was conducted to establish the effects of feeding refined soy oil (RSO) or whole soybeans (WSB) containing soy oil on DMI, animal performance, and enteric methane (CH4) emissions in young bulls. Thirty-six Charolais and Limousin cross-bred, young beef bulls (338 +/- 27 kg of BW, 218 +/- 17 d of age at the beginning of the experiment) were blocked by BW, age, and breed before being assigned in a randomized complete block design to 1 of 3 experimental treatments (n = 12). The experimental period lasted for 103 d, with enteric CH4 output recorded for 2 periods of 5 consecutive days on d 37 to 41 and d 79 to 83. The 3 dietary treatments consisted of a barley/soybean meal-based concentrate with 0 g/d of RSO; oil from WSB as 6% of DMI (WSB treatment); and oil from RSO as 6% of DMI (RSO treatment). Each diet had a 10:90 forage:concentrate ratio, using barley straw as the forage source. Diet affected DMI (P < or = 0.001) and GE intake (P < 0.05 during the CH4 measurement periods), with the WSB treatment producing the lowest values. The addition of WSB decreased ADG (P < 0.05) compared with the RSO treatment. The WSB treatment also decreased (P < 0.05) average daily carcass gain (ADCG). Both the RSO and WSB concentrates decreased (P < 0.05 to P < 0.001) daily enteric CH4 output when expressed in terms of liters per day, liters per kilogram of DMI, percentage of GE intake, liters per kilogram of ADG, and liters per kilogram of ADCG. Diet had no effect (P = 0.557) on ruminal protozoal numbers. The reductions in enteric CH4 were achieved at relatively high oil inclusion levels. Such oil levels have previously been reported to decrease DMI of high-forage diets, although no effect on DMI was noted with the low-forage diets fed in this experiment. This impact on DMI of high-forage diets may limit the range of diets for which this CH4 reduction strategy may be applicable. The inclusion level of WSB in the current experiment (27%) was beyond the palatability threshold of the bulls used and resulted in a marked decline in intake and performance. Therefore, WSB may have a role to play in ruminant diets, but only at a reduced inclusion rate.

Methane mitigation in ruminants: from microbe to the farm scale

“…Supplements rich in polyunsaturated FA such as linoleic acid (C18:2 from soybean and sunflower) and linolenic acid (C18:3 from linseed) also have a negative effect on CH 4 production (4.1% and 4.8% decrease per percentage unit of added lipids, 19 and 20 data, respectively). A decrease by 52% has been shown with a supplement of 5.8% linseed oil , whereas a decrease by 37% has been observed with 6% soybeans lipids (Jordan et al, 2006a). Data are less numerous for monounsaturated FA such as oleic acid (C18:1 from rapeseed; five data) and saturated fats (C16 and C18 from tallow; eight data), but these supplements result in decreases by 2.5% and 3.5% per percentage unit of added lipids, respectively.…”

“…This was confirmed by dose-response trials by Martin et al (2007b and) with three levels of extruded linseeds (rich in polyunsaturated FA) given to dairy cows, and by Jordan et al (2006b) with three levels of coconut oil (rich in medium-chain saturated FA) given to heifers. The form of lipid supply has been studied but inconsistent results have been obtained: CH 4 decrease was higher for whole sunflower seeds than for sunflower oil in a trial by Beauchemin et al (2007a) but higher for soybean oil than for whole soybeans (Jordan et al, 2006a) and for linseed oil than for rolled or extruded linseed . In practice, the use of seeds is preferred to that of refined oil because they are easier to use and less expensive.…”

Intake and performance of confined crossbred heifers fed different lipid sources

“…According to Martinez Marin (2007), approximately 20% of UFA ingested by ruminants reach the small intestine without undergoing complete biohydrogenation. However, increased or decreased UFA flow into the small intestine depends on the lipid source used and the diet composition (Jordan et al, 2006).…”

Effect of corn silage particle size and level of soybean oil on ruminal mat composition, distribution and consistency in Zel sheep

“…Ikwuegbu and Sutton (1982) found that infusion of 0, 13, 26 and 40 ml oil per day into the rumen of sheep reduced fiber digestibilities in the rumen by 44, 28, 18 and 14%, respectively. Fiber components covered with fat prevent access to rumen microorganisms (Smith, 2000), decrease microbial attachment to fiber particles (biofilm is not formed), reduce fiber breakdown and fermentation (Jordan et al, 2006), and prevent reduction of particle size and particle passage from the rumen, making feed intake to diminish (Onetti and Grummer, 2004;Jenkins et al, 1998). These fat effects cause functional specific gravity, which is the most important factor affecting removal of particles from the rumen; they also cause less increase (Firkins et al, 1998), which prevents the passage of digested particles from the rumen (Jordan et al, 2006).…”

“…Fiber components covered with fat prevent access to rumen microorganisms (Smith, 2000), decrease microbial attachment to fiber particles (biofilm is not formed), reduce fiber breakdown and fermentation (Jordan et al, 2006), and prevent reduction of particle size and particle passage from the rumen, making feed intake to diminish (Onetti and Grummer, 2004;Jenkins et al, 1998). These fat effects cause functional specific gravity, which is the most important factor affecting removal of particles from the rumen; they also cause less increase (Firkins et al, 1998), which prevents the passage of digested particles from the rumen (Jordan et al, 2006). Therefore, this research was designed to investigate the effects of two corn silage particles size and two levels of soybean oil consumption on intake and DM, OM, NDF, crude protein (CP), non-fibrous carbohydrate (NFC) and EE digestion, ruminal mat composition, distribution and consistency and chewing activity in sheep.…”