In vitro rumen fermentation and effect of protein fractions of canola meals on methane production

Canola provides oil for human consumption and a by-product from the extraction of its oil canola meal (CM), is used as a good quality protein and lipid supplement for ruminants. The aim of this study was to determine the chemical composition and fermentation profile associated with the potential for methane production of three types of CM: solvent-extracted CM of Brassica napus (CMBN), B. juncea (CMBJ) and cold press-extracted CM from B. napus (CPCM) used to feed ruminants. The protein content of canola meal ranged from 36 to 41 %. The acid and neutral detergent insoluble in nitrogen ranged from 1 to 2 % and 4 to 5 %, respectively. The lipid content of canola meal samples ranged from 2 % (CMBN, CMBJ) to 14 % (CPCM). In vitro, dry matter disappearance of CMBJ was higher than that of other types of CM at 4 h, 24 h and 48 h. Gas production from CMBJ was greater than that of CPCM and CMBN at 24 h and 48 h of incubation. CPCM produced lower methane than CMBJ at 48 h of incubation. CPCM produced a higher (p 0.05) molar proportion of propionate from 12 h to 48 h of incubation. In conclusion, this study found that CPCM could be a good source of protein (mainly PB2) and lipids in the feed of ruminants; it will decrease methane production and enhance propionate production. There was correlation between less methane production, and the content of lipids and PB2 in the three types of CM studied.

In vitro rumen fermentation and effect of protein fractions of canola meals on methane production

Canola provides oil for human consumption and a by-product from the extraction of its oil canola meal (CM), is used as a good quality protein and lipid supplement for ruminants. The aim of this study was to determine the chemical composition and fermentation profile associated with the potential for methane production of three types of CM: solvent-extracted CM of Brassica napus (CMBN), B. juncea (CMBJ) and cold press-extracted CM from B. napus (CPCM) used to feed ruminants. The protein content of canola meal ranged from 36 to 41 %. The acid and neutral detergent insoluble in nitrogen ranged from 1 to 2 % and 4 to 5 %, respectively. The lipid content of canola meal samples ranged from 2 % (CMBN, CMBJ) to 14 % (CPCM). In vitro, dry matter disappearance of CMBJ was higher than that of other types of CM at 4 h, 24 h and 48 h. Gas production from CMBJ was greater than that of CPCM and CMBN at 24 h and 48 h of incubation. CPCM produced lower methane than CMBJ at 48 h of incubation. CPCM produced a higher (p 0.05) molar proportion of propionate from 12 h to 48 h of incubation. In conclusion, this study found that CPCM could be a good source of protein (mainly PB2) and lipids in the feed of ruminants; it will decrease methane production and enhance propionate production. There was correlation between less methane production, and the content of lipids and PB2 in the three types of CM studied.(AU)

Relationship between glycerol administration to livestock 24 h before sacrifice and indicators of physiological and oxidative stress

The objective of this study was to evaluate the effect of oral administration of glycerol, as a source of energy, to steers 24 h before slaughter on biochemical indicators of physiological and oxidative stress. Fifty Zebu x Swiss-or Simental-cross steers were selected at random at the finalizing stage impending slaughter. Blood samples were collected from the jugular vein before administering the treatments and 24 h afterward. After sacrifice, samples of the Longissimus dorsi muscle were collected. Biochemical indicators evaluated in bovine serum were hematocrit (VGA), lactate dehydrogenase (LDH), lactate (LAC), cortisol (COR), glucose (GLU), β-hydroxybutyrate (BHT), creatine kinase enzyme (CK), free non-esterified fatty acids (NEFA), antioxidant activity (FRAP), thiobarbituric acid reactive substances (TBARS), and glutathione peroxidase reaction (GSH-Px). The variables evaluated in meat were TBARS, FRAP, pH, texture and shelf life. Analysis of the stress biomarkers evaluated in bovine serum did not reveal differences (P>0.05) between treatments T0 and T1 for the variables COR, VGA, GLU, NEFA, BHT or CK. There were, however, differences between sampling times for the variables FRAP (P = 0.021) and GSH (P = 0.006). The indicators FRAP and TBARS in the sampled meat were not different (P>0.05) between treatments. Meat pH changed over time (P=0.0002), but not its texture (P>0.05). It is concluded that the administration of glycerol as an energy supplement 24 h before sacrifice did not modify the balance of physiological constants of the evaluated steers, nor did it produce significant changes in shelf life of meat.(AU)

Relationship between glycerol administration to livestock 24 h before sacrifice and indicators of physiological and oxidative stress

The objective of this study was to evaluate the effect of oral administration of glycerol, as a source of energy, to steers 24 h before slaughter on biochemical indicators of physiological and oxidative stress. Fifty Zebu x Swiss-or Simental-cross steers were selected at random at the finalizing stage impending slaughter. Blood samples were collected from the jugular vein before administering the treatments and 24 h afterward. After sacrifice, samples of the Longissimus dorsi muscle were collected. Biochemical indicators evaluated in bovine serum were hematocrit (VGA), lactate dehydrogenase (LDH), lactate (LAC), cortisol (COR), glucose (GLU), β-hydroxybutyrate (BHT), creatine kinase enzyme (CK), free non-esterified fatty acids (NEFA), antioxidant activity (FRAP), thiobarbituric acid reactive substances (TBARS), and glutathione peroxidase reaction (GSH-Px). The variables evaluated in meat were TBARS, FRAP, pH, texture and shelf life. Analysis of the stress biomarkers evaluated in bovine serum did not reveal differences (P>0.05) between treatments T0 and T1 for the variables COR, VGA, GLU, NEFA, BHT or CK. There were, however, differences between sampling times for the variables FRAP (P = 0.021) and GSH (P = 0.006). The indicators FRAP and TBARS in the sampled meat were not different (P>0.05) between treatments. Meat pH changed over time (P=0.0002), but not its texture (P>0.05). It is concluded that the administration of glycerol as an energy supplement 24 h before sacrifice did not modify the balance of physiological constants of the evaluated steers, nor did it produce significant changes in shelf life of meat.