Intake, nutrient digestibility, rumen parameters, growth rate, carcase characteristics and cannabinoid residues of sheep fed pelleted rations containing hemp (Cannabis sativa L.) stubble.

The feeding value and impact of hemp stubble in the diet of ruminants is unknown. Fifteen Merino castrated male sheep were maintained in individual pens and fed one of three pelletized experimental inclusion diets, as a 0% (Control), 28% (Hemp 1), and 56% (Hemp 2) pellet that delivered a diet meeting the nutrient requirements of the animals. Inclusion of hemp stubble had no effect (P > 0.05) on either DM intake, live weight gain or the feed to gain ratio but positively impacted (P < 0.05) on nutrient digestibility. Hemp stubble inclusion increased the concentration (but not molar proportions) of acetic and butyric acids and increased both the concentrations and molar proportions of iso-butyric, iso-valeric, hexanoic and heptanoic acids, possibly due to increased protein digestibility and/or changes in the composition of rumen cellulolytic bacteria. Tetrahydrocannabinolic acid (THCA) was the only cannabinoid found in plasma in the sheep fed the hemp-containing diets, and this was found at very low concentrations (<16 µg/L). The psychoactive cannabinoid delta-9-tetrahydrocannabinol (Δ 9-THC) was not detected in any plasma samples. THCA was detected in the liver of two sheep fed the Hemp 1 pellets and two sheep fed the Hemp 2 pellets. Cannabidiol (CBD) was detected in the liver of one sheep fed the Hemp 2 pellets (but no liver THCA was detected in this sheep). Δ 9-THC was detected in both the kidney fat and subcutaneous fat of all sheep fed hemp stubble, with the concentrations being higher (P < 0.05) in the sheep fed the Hemp 1 pellets. THCA was also detected in the subcutaneous fat of one of the sheep fed the Hemp 1 pellets. Four of the five sheep fed the Hemp 1 pellet and one of the five sheep fed Hemp 2 pellet had detectable levels of Δ 9-THC in the meat (loin). No other cannabinoids were detected in the meat. Current food standards regulations in Australia prohibit presence of any cannabinoid residues in commercial meat products; thus, determination of a withholding period is required to enable the safe feeding of hemp-stubble to sheep. Further research is also required to gain a greater understanding of the rumen metabolism of cannabinoids.

Dietary Lecithin Supplementation Can Improve the Quality of the M. Longissimus thoracis.

Forty crossbred (Large White × Landrace × Duroc) female pigs (16.4 kg ± 0.94 kg) were used to investigate the effect of dietary lecithin supplementation on growth performance and pork quality. Pigs were randomly allocated to a commercial diet containing either 0, 3, 15 or 75 g lecithin/kg of feed during the grower and finisher growth phase. Pork from pigs consuming the diets containing 15 g and 75 g lecithin/kg had lower hardness ( P < 0.001) and chewiness ( P < 0.01) values compared to the controls. Dietary lecithin supplementation at 75 g/kg significantly increased ( P < 0.05) the linoleic acid and reduced ( P < 0.05) the myristic acid levels of pork compared to the control and the 3 g/kg and 15 g/kg lecithin supplemented treatments. Pigs fed the 75 g/kg lecithin supplemented diet had lower plasma cholesterol ( P < 0.05) at slaughter compared to pigs fed the control diet and the 3 g/kg and 15 g/kg lecithin supplemented treatments. These data indicate that dietary lecithin supplementation has the potential to improve the quality attributes of pork from female pigs.