Effects of replacing grass silage with maize silages differing in inclusion level and maturity on the performance, meat quality and concentrate-sparing effect of beef cattle

Abstract

The effects of maturity of maize at harvest, level of inclusion and potential interactions on the performance, carcass composition, meat quality and potential concentrate-sparing effect when offered to finishing beef cattle were studied. Two maize silages were ensiled that had dry matter (DM) concentrations of 217 and 304 g/kg and starch concentrations of 55 and 258 g/kg DM, respectively. Grass silage was offered as the sole forage supplemented with either 4 or 8 kg concentrate/steer daily or in addition with one of the two maize silages at a ratio 0.5 : 0.5, on a DM basis, maize silage : grass silage supplemented with 4 kg concentrate daily. The two maize silages were also offered as the sole forage supplemented with 4 kg concentrate/steer daily. The forages were offered ad libitum. The six diets were offered to 72 steers (initial live weight 522 s.d. 23.5 kg) for 146 days. There were significant interactions (P , 0.05) between maize maturity and inclusion level for food intake, fibre digestibility and daily gain. For the grass silage supplemented with 4 or 8 kg concentrate, and the maize silages with DM concentrations of 217 and 304 g/kg offered as 0.5 or 1.0 of the forage component of the diet, total DM intakes were 8.3, 9.8, 8.9, 8.2, 9.2 and 9.8 kg DM/day (s.e. 0.27); live-weight gains were 0.74, 1.17, 0.86, 0.71, 0.88 and 1.03 kg/day (s.e. 0.057); and carcass gains were 0.48, 0.73, 0.56, 0.46, 0.56 and 0.63 kg/day (s.e. 0.037), respectively. Increasing the level of concentrate (offered with grass silage), maize maturity and level of maize inclusion reduced (P , 0.05) fat b* (yellowness). The potential daily concentrate-sparing effect, as determined by carcass gain, for the maize silages with DM concentrations of 217 and 304 g/kg offered as 0.5 and 1.0 of the forage component of the diet were 1.3, 20.3, 1.3 and 2.4 kg fresh weight, respectively. It is concluded that the response, in animal performance, including maize silage is dependent on the stage of maturity and level of inclusion in the diet. Maize silage with a DM of 304 g/kg offered ad libitum increased carcass gain by 31%, because of a combination of increased metabolizable energy (ME) intake and improved efficiency of utilization of ME, and produced carcasses with whiter fat.Keywords: beef cattle, maize silage maturity, maize inclusion level, meat quality, concentrate feed level ImplicationsThe response to maize silage inclusion in grass silage-based diets of beef cattle depends on maturity at harvest and level of inclusion in the diet. Maize silage with a dry matter concentration of 304 g/kg offered as the sole forage resulted in the highest level of performance because of a combination of increased forage intake and improved efficiency of utilization of metabolizable energy. Maturity of maize silage had no impact on animal performance when offered as 0.5 of the forage. Maize silage has a daily concentrate-sparing effect per steer of up to 2.4 kg. Therefore, increasing the inclusion of maize, harvested at the optimum stage of maturity, in the diet...

Identification of key rearing factors to manage cattle carcass fatness and conformation scores during the fattening period

“…In accordance with our results, many studies showed that the carcasses are fattier when the DMI of steers and young bulls are increased (Cerdeño et al 2006;Keane et al 2006;Keady et al 2013). As observed in the FAT-CC model, studies of the literature observed also an increase of carcass fatness score when the fattening period is extended, in the cull cows and the steers (Keane et al 2006;Vestergaard et al 2007).…”

Preliminary Study to Determinate the Effect of the Rearing Managements Applied during Heifers’ Whole Life on Carcass and Flank Steak Quality

“…In contrast to the results of Price et al [ 61 ] in young bulls and steers, in our study, the combination of a higher hay percentage in the fattening diet and heavier slaughter weight did not lead to a lower dressing%. As demonstrated in many studies, the fattening diet composition could have no impact on the dressing% in cattle [ 55 , 57 , 62 , 63 ]. It could explain the few differences observed between the four rearing managements applied during the heifers’ whole life considered in our study.…”

“…This observation confirms the results obtained by Keane and Allen and Ellies-Oury et al [ 15 , 64 ] in steers. According to many studies, the fattening diet composition would not seem to have any impact on the conformation score in heifers and steers [ 55 , 61 , 63 ]. On the other hand, WLP-A with the longest pasture duration produced carcasses with the lowest conformation score (R+).…”

Growth performance, carcass trait, meat quality and oxidative stability of beef cattle offered alternative silages in a finishing ration

“…Similarly, Juniper et al (2005) reported no difference in muscle color when grass silage was replaced by increasing amounts of maize silage in the diet of beef steers. Dawson (2012) and Keady et al (2013) detected no difference in muscle color or aspect of palatability when grass silage was replaced with maize silage. Given that moisture and intramuscular fat contents were significantly different between the treatments and generally intramuscular fat was positively correlated to the tenderness and water holding capacity of beef muscle, it was expected that shear force and water holding capacity of beef muscle would be dissimilar.…”