The susceptibility of meat and meat products (MP) to oxidation and microbial deterioration poses a risk to the nutritional quality, safety, and shelf life of the product. This analysis provides a brief overview of how bioactive compounds (BC) impact meat and MP preservation, and how they can be utilized for preservation purposes. The use of BC, particularly plant-based antioxidants, can reduce the rate of auto-oxidation and microbial growth, thereby extending the shelf life of MP. These BC include polyphenols, flavonoids, tannins, terpenes, alkaloids, saponins, and coumarins, which have antioxidant and antimicrobial properties. Bioactive compounds can act as preservatives and improve the sensory and physicochemical properties of MP when added under appropriate conditions and concentrations. However, the inappropriate extraction, concentration, or addition of BC can also lead to undesired effects. Nonetheless, BC have not been associated with chronic-degenerative diseases and are considered safe for human consumption. MP auto-oxidation leads to the generation of reactive oxygen species, biogenic amines, malonaldehyde (MDA), and metmyoglobin oxidation products, which are detrimental to human health. The addition of BC at a concentration ranging from 0.025 to 2.5% (w/w in powdered or v/w in oil or liquid extracts) can act as a preservative, improving color, texture, and shelf life. The combination of BC with other techniques, such as encapsulation and the use of intelligent films, can further extend the shelf life of MP. In the future, it will be necessary to examine the phytochemical profile of plants that have been used in traditional medicine and cooking for generations to determine their feasibility in MP preservation.

El metano (CH4) es un gas subproducto de la fermentación de los carbohidratos en el rumen. La agricultura contribuye con el 47% de las emisiones antropogénicas de CH4, siendo los rumiantes responsables del 39% de las emisiones de metano entérico. Este gas de efecto invernadero (GEI) tiene un potencial de calentamiento global 25 veces más que el CO2 y representa una pérdida de hasta el 12% de la energía total consumida por los rumiantes. Este trabajo describe los mecanismos de acción de los taninos condensados contenidos en follajes y frutos y su efecto en los microbios del rumen, así como su potencial en la mitigación de las emisiones de CH4. Los hallazgos sugieren que los taninos condensados reducen la población de protozoos hasta 79%, reduciendo además los metanogenos del rumen hasta en 33%. Los taninos condensados se unen a proteínas y polisacáridos formando complejos, reduciendo así la digestibilidad de la metería seca y orgánica y la producción de H2 metabólico, el que es usado por metanogenos para la reducción del CO2 a CH4. Estudios in vitro sugieren que los taninos condensados pueden reducir el CH4 en el rumen hasta 63%, mientras que in vivo se han registrado reducciones hasta 58% en la producción de CH4. Además, la incorporación de taninos condensados en la ración de rumiantes tiene el potencial de aumentar la ganancia de peso en 26%, relacionando esto al aumento en el flujo de proteína de baja degradación ruminal al intestino delgado o la reducción de la energía perdida en forma de CH4 en el rumen. Se concluye que la incorporación de taninos condensados en la ración de los rumiantes en concentración de 3-6% de materia seca puede reducir las emisiones de CH4 así como mejorar la ganancia de peso y producción de leche de los animales productivos.

The present study was designed to evaluate the relationship between the body measurements (BMs) and carcass characteristics of hair sheep lambs. Twenty hours before slaughter, the shrunk body weight (SBW) and BMs were recorded. The BMs involved were height at withers (HW), rib depth (RD), body diagonal length (BDL), body length (BL), pelvic girdle length (PGL), rump depth (RuD), rump height (RH), pin-bone width (PBW), hook-bone width (HBW), abdomen width (AW), girth (GC), and abdomen circumference (AC). After slaughter, the carcasses were weighed and chilled for 24 h at 1 °C, and then were split by the dorsal midline. The left-half was dissected into total soft tissues (muscle + fat; TST) and bone (BON), which were weighed separately. The weights of viscera and organs (VIS), internal fat (IF), and offals (OFF—skin, head, feet, tail, and blood) were also recorded. The equations obtained for predicting SBW, HCW, and CCW had an r² ranging from 0.89 to 0.99, and those for predicting the TST and BON had an r² ranging from 0.74 to 0.91, demonstrating satisfactory accuracy. Our results indicated that use of BMs could accurately and precisely be used as a useful tool for predicting carcass characteristics of hair sheep lambs.

The aim of the experiment was to assess the effect of increasing amounts of Leucaena leucocephala forage on dry matter intake (DMI), organic matter intake (OMI), enteric methane production, rumen fermentation pattern and protozoa population in cattle fed Pennisetum purpureum and housed in respiration chambers. Five crossbred heifers (Bos taurus×Bos indicus) (BW: 295±6 kg) were fed chopped P. purpureum grass and increasing levels of L. leucocephala (0%, 20%, 40%, 60%, and 80% of dry matter [DM]) in a 5×5 Latin square design. The voluntary intake and methane production were measured for 23 h per day in respiration chambers; molar proportions of volatile fatty acids (VFAs) were determined at 6 h postprandial period. Molar concentration of VFAs in rumen liquor were similar (p>0.05) between treatments. However, methane production decreased linearly (p0.05) in rumen protozoa population were found. Inclusion of 80% of L. leucocephala in the diet of heifers fed low-quality tropical forages has the capacity to reduce up to 61.3% enteric methane emission without affecting DMI, OMI, and protozoa population in rumen liquor.