Methane excretion in the growing pig

Abstract

1. Total methane excretion (CH, in breath+flatus) was measured in two experiments with thirty-six castrated male pigs (Danish Landrace) during the growth period from 20 to 120 kg live weight (LW). In Expt A, twenty-eight pigs were fed on a commercial diet alternately at high (HFL; metabolizable energy (ME) 1234 (SE 41) kJ/kg LW0'75) or low (LFL; ME 784 (SE 31) kJ/kg LW0'75) feed levels in different weight classes. In Expt B, eight pigs were constantly fed on a semi-purified diet at HFL without (-oil) or with 90 g soya-bean oiI/kg diet (foil) corresponding to daily intakes of ME of 1339 (SE 11) and 1413 (SE 8) kJ/kg LW0"5 respectively.2. CH, excretion was measured during 24 h respiration trials in open-air-circulation chambers. 3. About 1 litre CH, was excreted per day at 2&25 kg LW increasing to a maximum of 12 litres at 120 kg LW, which corresponded to no more than 1.2% of dietary gross energy.4. In Expt A, CH, excretion increased linearly with LW, while in Expt B the increase was linear until about 70 kg LW, when it reached a plateau. On average LFL reduced CH, excretion by 23% compared with HFL. When related to dry matter (DM) intake, however, the pigs on LFL excreted 3.1 litres CH,/kg dietary DM and those on HFL 2.5 litres CH,/kg dietary DM, the difference being significant (P < 0.05). In Expt B the inclusion of soya-bean oil in the basal diet (+oil) reduced CH, excretion by 26% compared with the diet without oil (-oil). The pigs receiving the basal diet excreted 5.2 litres CH,/kg DM and the pigs receiving soya-bean oil 4.3 litres CH,/kg DM, the difference being highly significant (P < 0.001). All differences between Expt A and B in CH, excretion based on DM intake were highly significant (P < 0.001). 5.The results are discussed in relation to gas production in ruminants, rats and humans. It is suggested that flatus production may not only be reduced by changing the composition of the dietary carbohydrates, but also by inclusion of a polyunsaturated oil in the diet of simple-stomached animals and humans.Fermentation of carbohydrates in the hind-gut results in the formation of gases including hydrogen, carbon dioxide and methane. The main part is excreted in flatus, while a smaller part is absorbed into the bloodstream and excreted in expired air. CH, production has been studied extensively in ruminants and in vitro, but to a lesser extent in the hind-gut in simple-stomached animals and in man.In the rumen, CH, is formed by reduction of CO, and, to some extent, from formate (Hungate, 1968). CH, excretion represents a loss of dietary energy as it contains 39.55 kJ/1 (Brouwer, 1965). In growing calves the total loss of CH, amounts to 50-100 litres daily depending on the size of the animal, feed composition, feed level and digestibility of the feed, and it constitutes a loss of energy corresponding to 4-1 1 % of dietary gross energy (GE) (Thorbek, 1980). CH, production in the hind-gut of growing pigs amounts to only a few litres daily and represents an energy loss of about 0.2-1.0% of GE (Verstegen, 1971 ;Hoffma...

Enteric Methane Emission from Pigs

“…The effect of body weight was minor, however, significant in agreement with the studies by Christensen & Thorbek (1987) and Noblet & Shi (1994). However, Kirchgessner and coworkers concluded in a summary of several of their experiments that methanogenesis in pigs is fairly independent of live weight if feeding condition is kept constant.…”

“…A reduced feed intake allow more time for fermentation and as a result more enteric CH 4 is produced as found by Christensen & Thorbek (1987) in a study with reduced feed intake to growing pigs. This could also be the case when adult sows in the dry period and during pregnancy are fed relative restricted (2-2.5 kg DM per day) in order not to gain excessive weight because this may cause health problems around farrowing and lactation.…”

“…The technique applied is the so called indirect principle which means that the atmospheric air is ventilated through the chambers and the amount of air is measured together with the concentration of oxygen, carbon dioxide, methane and hydrogen in both in-going and out-going air (Jørgensen, 2001;. When the consumed amount of oxygen and produced amount of carbon dioxide and methane is known, the heat production can be calculated (Christensen & Thorbek, 1987;Jakobsen et al 2005). In most cases both nitrogen (N) and energy balances have been performed.…”

Influence of dietary components on development of the microbiota in single-stomached species

“…It has been suggested that dietary fat, if it escapes pre-caecal digestion, might reduce the number of micro-organisms in rats. This was supported by data showing a reduced methane production in pigs receiving fat in their diets (Christensen & Thorbek, 1987). However, in a human study, Cummings et al (1978) found no effect of diets with high or low animal fat (62 or 152 g/d) on the relative numbers of faecal bacterial groups, including Enterobacteriaceae, Enterococcus, Bacteroides, lactobacilli and clostridia.…”

Digestive and Metabolic Utilization of Feed Energy in Swine: Application to Energy Evaluation Systems

“…More generally, methane production increases with pig body weight and DF level in the diet. The energy loss as methane would represent 5 to 10% of fermented energy (Christensen and Thorbek, 1984;Kirchgessner et al, 1987). The hydrogen production in pigs is rather low but very few measurements have been carried out (Jensen and Jorgensen, 1994).…”