Health-promoting properties of meat from once-calved and maiden heifers

Beef has a high nutritional value owing to the presence of minerals, vitamins, polyunsaturated fatty acids (PUFA) and selected protein fractions. The objective of this study was to investigate the influence of calving and nursing on the fatty acid profile and the content of minerals and vitamins in the meat of crossbred (Limousine x Polish Holstein-Friesian) once-calved heifers in comparison with the meat of maiden heifers. At 15 months of age, once-calved heifers were inseminated with the semen of Limousine bulls. After calving and lactation, they were slaughtered. Meat samples were collected from m. longissimus dorsi (MLD). The fatty acid composition was determined with the use of a gas chromatograph. The content of 5 minerals (potassium, sodium, magnesium, zinc, iron) was determined by atomic absorption spectrometry. The content of vitamins A and E was determined by high-performance liquid chromatography. Gestation and nursing had a negligent effect on the content of functional components in the meat of oncecalved heifers, in comparison with the meat of heifers. The meat of heifers contained more vaccenic acid (TVA) (C 18:1 T10+11), arachidonic acid (AA) (C 20:4) and docosahexaenoic acid (DHA) (C 22:6), whereas the meat of once-calved heifers was more abundant in oleic acid, zinc, iron and vitamin E (P ≤ 0.01). Commercially crossbred heifers can be included in once-bred heifer production systems, which create a possibility of producing additional offspring plus higher body weight of heifers with no adverse effect on the functional properties.