Effects of low and high levels of maternal nutrition consumed for the entirety of gestation on the development of muscle, adipose tissue, bone, and the organs of Wagyu cattle fetuses

Abstract

This study aimed to investigate the effects of high and low levels of energy intake during the entire gestation period on the skeletal muscle development, organ development, and adipose tissue accumulation in fetuses of Wagyu (Japanese Black) cows, a breed with highly marbled beef. Cows were allocated to a high-nutrition (n = 6) group (fed 120% of the nutritional requirement) or low-nutrition (n = 6) group (fed 60% of the nutritional requirement). The cows were artificially inseminated with semen from the same sire, and the fetuses were removed by cesarean section at 260 AE 8.3 days of fetal age and slaughtered. The whole-body, total muscle, adipose, and bone masses of the fetal half-carcasses were significantly higher in the high-nutrition group than the low-nutrition group (p = 0.0018, 0.009, 0.0004, and 0.0362, respectively). Fifteen of 20 individual muscles, five of six fat depots, nine of 17 organs, and seven of 12 bones that were investigated had significantly higher masses in the high-nutrition group than the low-nutrition group. The crude components and amino acid composition of the longissimus muscle significantly differed between the low-and high-nutrition groups. These data indicate that maternal nutrition during gestation has a marked effect on the muscle, bone, and adipose tissue development of Wagyu cattle fetuses.

Maternal Undernutrition during Pregnancy Alters Amino Acid Metabolism and Gene Expression Associated with Energy Metabolism and Angiogenesis in Fetal Calf Muscle

“…Recently, we demonstrated that the skeletal muscle weight of fetuses of dams fed with 60% of crude protein (CP), crude fat (CF), and energy requirements was 1.27-to 1.72-fold lower than that of the fetuses of dams fed with 120% of the nutritional requirements [10]. The phenotypic alteration observed in this study promotes understanding the mechanism underlying the effect of MUN on muscle development and tissue metabolism in the fetuses.…”

“…In contrast to the effect on the myogenic process, the effect of MUN on metabolism of fetal skeletal muscle tissue remains poorly understood. The fetal skeletal muscle mass was reduced by MUN [10], possibly due to the retardation of whole process of skeletal muscle development. This could be a result of insufficient supply of energy and nutrient components that were required for the myogenic differentiation, muscle fiber maturation, and protein accumulation.…”

“…These studies have suggested that alteration of fetal skeletal muscle metabolism caused by MUN is crucial for the muscle development, however, the effect of MUN on fetal skeletal muscle metabolism has been poorly elucidated. This could be partly due to lack of experimental system leading to phenotypic alteration of fetal development by MUN, which can be overcome by setting the nutrient levels for dams to 60 and 120% as the low and high levels, respectively [10].…”

“…This study aimed to elucidate the effect of MUN on fetal skeletal muscle metabolism that links to the retardation of the fetal muscle development in Japanese Black cows. To this end, we used a design in which the pregnant dams were fed on low-nutrition (LN) and high-nutrition (HN) diets (based on protein, fat, and energy contents) during the whole gestation (until month 8.5 post-conception) [10]. To find the phenotypic effect of MUN on fetal development under the limited knowledge regarding the MUN effect in cattle, this design is beneficial due to its marked phenotypic alteration of fetal muscles in the LN group [10].…”

“…To this end, we used a design in which the pregnant dams were fed on low-nutrition (LN) and high-nutrition (HN) diets (based on protein, fat, and energy contents) during the whole gestation (until month 8.5 post-conception) [10]. To find the phenotypic effect of MUN on fetal development under the limited knowledge regarding the MUN effect in cattle, this design is beneficial due to its marked phenotypic alteration of fetal muscles in the LN group [10]. The LN and HN groups were set to 60 and 120% of the recommended nutritional level, respectively, based on the standard diet model for prepregnant BW in the Japanese Feeding Standard for Beef Cattle (JFSBC, 2008 ed.)…”