Pattern of tissue deposition, gain and body composition of Nellore, F1 Simmental × Nellore and F1 Angus × Nellore steers fed at maintenance or ad libitum with two levels of concentrate in the diet

Abstract

-Sixty 18-month-old steers (20 Nellore, 20 F 1 Simmental × Nellore and 20 F 1 Angus × Nellore with average body weight of 265.6±6.4 kg; 325.3±4.7 kg and 324.6±6.0 kg, respectively) were used. The effects of feeding regime and genetic group on physical carcass composition, empty body composition, composition of the gain, as well as the pattern of tissue deposition were evaluated in this trial. The interaction between genetic group and feeding regime was not significant for any variable evaluated. Animals fed at the maintenance level produced carcass with larger proportions of bones and muscle than the animals fed ad libitum and Nellore animals had larger muscle portion and smaller adipose tissue portion on the carcass than the crossbred animals. Nellore animals and those fed at maintenance had smaller amount of total fat in the carcass than the crossbred animals and those fed ad libitum, respectively. Fat was deposited more pronouncedly in the intermuscular depot, followed by the visceral depot. The rate of deposition of the carcass tissues was smaller in the Nellore animals and in the animals fed the diet with concentrate allowance equivalent to 1% body weight (except for subcutaneous fat tissue), when compared with the crossbred animals and those fed the diet with 2% BW on concentrate, respectively. The rate of fat deposition on the visceral depot was larger in the F 1 Angus × Nellore animals and on those fed the 2% of BW of concentrate diet when compared with F 1 Simmental × Nellore animals and those fed the diet with the lowest concentrate allowance (1% BW).

Effects of Megasphaera elsdenii administration on performance and carcass traits of finishing Bos indicus feedlot cattle

“…In fact, in a traditional feedlot production setting, subcutaneous depots are stored and formed prior to intramuscular fat depots (i.e., marbling; Vernon, 1981 ; Sainz and Hasting, 2000 ; Oliveira et al, 2011 ) and, therefore, it can be speculated that intramuscular fat depot differentiation would still occur in non-castrated Bos taurus indicus animals as they would achieve mature BW ( Valadares Filho et al, 2016 ). Likewise, Costa et al (2020) reported similar marbling scores in non-castrated Bos taurus indicus animals slaughtered at similar BW and offered high-concentrate diets with similar ether extract contents as used herein.…”

Supplementing Trace Minerals to Beef Cows during Gestation to Enhance Productive and Health Responses of the Offspring

“…Hence, Harvey et al [ 85 ] speculated that heifers born to INR supplemented cows had a greater population of satellite cells undergoing differentiation at the time of sampling. Further, no treatment differences were detected in the LM for genes associated with adipogenic activities ( Table 5 ), however, the intramuscular region is typically the last depot for adipose tissue to be deposited in the growing animal [ 90 ] and the puberty process is more likely influenced by subcutaneous fat accretion [ 91 , 92 , 93 ]. Myogenic factors are downregulated as cattle mature and muscle fibers are fully developed [ 5 , 94 ]; therefore Harvey et al [ 85 ] noted that treatment differences noted in the LM for mRNA expression of myogenin and PAX7 may be indicative of accelerated physiological maturation in heifers born to AAC-supplemented cows [ 95 ].…”

Body composition and composition of gain of growing beef bulls fed rations with varying energy concentrations

“…Beef breeds show higher muscle and lower body fat content than dairy breeds ( Albertí et al, 2008 ; Pfuhl et al, 2007 ), while cows and heifers are reported to show higher fat content than steers and bulls ( Venkata Reddy et al, 2015 ). The body composition of an animal can be altered by changing the genetics through selective breeding or crossbreeding ( Bonilha et al, 2014 ; Oliveira et al, 2011 ), as well as by changing external influences as nutrition ( Keogh, Waters, Kelly, & Kenny, 2015 ; McCurdy, Horn, Wagner, Lancaster, & Krehbiel, 2010 ). However, the proportions of body tissues in cattle also change with increasing age and live weight of the animal until maturity is reached.…”