Marbling in feedlot cattle

The degree of marbling and the thickness of subcutaneous fat at the 10th rib cut of the M. longissimus was studied in three groups of 450 kg Santa Gertrudis crossbred and Hereford steers fattened for 120 days on three grain-based diets in a commercial feedlot. Mean cold carcase weight was 311 kg for each breed of steer and differed by only 4 kg for each dietary treatment. The percentage intramuscular fat was similar for the two breeds of cattle but subcutaneous fat thickness was 25 per cent greater in the Herefords than in the Santa Gertrudis crossbreds. Visual marbling score was well correlated (r = 0.81) with the percentage intramuscular fat. Intramuscular adipocyte size was much less than subcutaneous adipocyte size and the Santa Gertrudis crossbreds tended to have larger subcutaneous adipocytes than the Herefords. These findings are discussed in relation to the differences between breeds of cattle in the rate of deposition and the distribution of carcase fat and the production of highly-marbled beef.

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Características de carcaça e componentes não-carcaça de tourinhos ½ Purunã x ½ Canchim alimentados com rações contendo três teores de concentrado

Semina Ciências Agrárias ◽

10.5433/1679-0359.2018v39n6p2727 ◽

2018 ◽

Vol 39 (6) ◽

pp. 2727

Author(s):

Leandro Bren ◽

Paulo Rossi Junior ◽

José Luis Moletta ◽

Eduardo Michelon do Nascimento ◽

Sergio Rodrigo Fernandes ◽

...

Keyword(s):

Energy Content ◽

Subcutaneous Fat ◽

Feedlot Cattle ◽

Tissue Composition ◽

Internal Organs ◽

Mean Values ◽

Linear Effect ◽

Subcutaneous Fat Thickness ◽

Fat Thickness ◽

Average Body

Improving the quality and energy content of rations increases performance in feedlot cattle, resulting in higher weight at slaughter, better carcass quality and a higher yield of non-carcass components. The purpose of this study was to evaluate the effect of increasing concentrate content in the ration on the carcass traits and weight of non-carcass components of young bulls finished in a feedlot. Eighteen young crossbred ½ Purunã x ½ Canchim bulls were used, with an average body weight (BW) of 278 kg and 12 months of age at the start of the experiment. The experimental design was completely randomized with three treatments and six replicates, where the treatments were the contents of 0.71, 0.97 and 1.24% BW day-1 of concentrate in the ration, on a dry matter (DM) basis. Corn silage was used as roughage and was provided ad libitum during the experiment. The young bulls were kept in the feedlot for 168 days and slaughtered at 17 months of age. There was a linear effect of concentrate content on the slaughter weight (SW) and hot carcass weight (HCW), which increased from 433 to 485 kg and from 248 to 280 kg between 0.71 and 1.24% BW in DM day-1 of concentrate. This represented an increase of 9.87 kg in SW and 6.16 kg in HCW for each 0.10% BW in DM day-1 of concentrate added to the ration. The hot carcass yield, rib eye area, subcutaneous fat thickness and the proportions of bone, muscle and fat in the carcass were not affected by the concentrate content and showed mean values of 57.3%, 79.6 cm2, 3.20 mm, 14.88%, 65.21% and 20.67%, respectively. There was a linear effect of concentrate content on the carcass temperature after cooling, which increased from 8.1 to 9.0 oC between 0.71 and 1.24% BW in DM day-1 of concentrate. An increase of 0.16 oC in the post-cooling carcass temperature for each 0.10% BW in DM day-1 of concentrate added to the ration was observed. The weight of internal organs and the perirenal and internal fat deposition were not affected by the concentrate content. The inclusion of 1.24% BW in DM day-1 of concentrate in the ration is recommended to obtain high SW and high HCW. Below this level, the carcass tissue composition and weight of non-carcass components are not modified.

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Carcass characteristics of immunocastrated steers finished on diets with different energy patterns

South African Journal of Animal Science ◽

10.4314/sajas.v51i1.13 ◽

2021 ◽

Vol 51 (1) ◽

Author(s):

A.F. De Moura ◽

D.C.A. Filho ◽

I.L. Brondani ◽

L.B. Pereira ◽

G. Joner ◽

...

Keyword(s):

Energy Levels ◽

Subcutaneous Fat ◽

Carcass Characteristics ◽

Dietary Energy ◽

Marbling Score ◽

Randomized Design ◽

Subcutaneous Fat Thickness ◽

Fat Thickness ◽

Completely Randomized Design ◽

Dietary Treatments

The aim of this study was to evaluate the effects of various dietary energy levels on the carcass and meat characteristics of feedlot-finished steers. A total of 27 purebred and crossbred Charolais and Nellore steers were used, with a mean initial age of 22 months and weight of 253 kg. The animals were allotted to a completely randomized design with three treatments and nine replicates each. Dietary treatments were arranged so that the average forage to concentrate ratio (FCR) was equivalent to that of a constant FCR treatment. The treatments consisted of CT (constant FCR at 60 to 40), CT5 (starting with 70: 30 FCR and finishing with 50: 50 FCR, that is, a mean overall FCR of 60: 40), and CT10 (starting with 80: 20 FCR and finishing with 40: 60, that is, a mean overall FCR of 60: 40). The dietary treatments did not affect slaughter weight, carcass weight, carcass conformation, physiological maturity, subcutaneous fat thickness, ribeye area, marbling score, and carcass measurements or the yield of commercial cuts. Chilling loss was higher in CT10 steers (2.41%) than in CT (2.26%) and CT5 (2.15%).

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Sources of variation influencing the use of real-time ultrasound to predict intramuscular fat in live beef cattle

Canadian Journal of Animal Science ◽

10.4141/a01-058 ◽

2002 ◽

Vol 82 (2) ◽

pp. 133-139 ◽

Cited By ~ 8

Author(s):

A. Chambaz ◽

P. -A. Dufey ◽

M. Kreuzer ◽

J. Gresham

Keyword(s):

Beef Cattle ◽

Subcutaneous Fat ◽

Intramuscular Fat ◽

Independent Variables ◽

Breed Group ◽

Sources Of Variation ◽

Subcutaneous Fat Thickness ◽

Fat Thickness ◽

Best Fit ◽

Scanning Session

A total of 123 steers of six European breeds (Angus, Simmental, Charolais, Limousin, Blonde d'Aquitaine, Piedmontese) were used (i) to evaluate the precision of the ultrasound-predicted intramuscular fat (USIMF) and its sources of variation using the current Pie QUIP technology and (ii) to develop improved models for predicting USIMF. Steers were slaughtered when they reached the target value of 3.5% USIMF. Hide samples were obtained 3 d before slaughter by shot-biopsy. After slaughter, a sample of the longissimus muscle was used to determine actual chemical intramuscular fat (EEIMF), collagen content and solubility. Among the variables available during a chute-side scanning session, hide thickness and ultrasound subcutaneous fat thickness at the 12th and 13th ribs were shown to be significantly correlated with EEIMF. These two variables were selected as possible independent variables to evaluate the construction of new models. The model with the best fit included USIMF, hide thickness and liveweight and had a standard error of prediction of 0.96%, which is similar to other published technologies. Breed group and collagen-related traits did not influence USIMF estimation. Finally, the revised Pie QUIP technology should be considered as one technology of choice to predict EEIMFcontent in live animals. Key words: Beef, cattle, ultrasound, intramuscular fat, hide thickness, collagen

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Meat quality of cattle subjected to period of aging process: a cross-heifer study

Semina Ciências Agrárias ◽

10.5433/1679-0359.2021v42n3p1175 ◽

2021 ◽

Vol 42 (3) ◽

pp. 1175-1188

Author(s):

Lucy Mery Antonia Surita ◽

Marina de Nadai Bonin Gomes ◽

Brayan Dias Dauria ◽

Rodrigo da Costa Gomes ◽

Marilia Williane Filgueira Pereira ◽

...

Keyword(s):

Meat Quality ◽

Shear Force ◽

Subcutaneous Fat ◽

Fat Distribution ◽

Ether Extract ◽

Marbling Score ◽

Subcutaneous Fat Thickness ◽

Fat Thickness ◽

Effects Of Aging

The aim of this study was to evaluate the effects of aging on meat quality of crossbred heifers. Qualitative and quantitative evaluations of carcasses and meat of 148 crossbred heifers with an average age of 13 months and 407.5 ± 29.22 kg body weight at slaughter were performed. After cooling for 24 h, the carcasses were evaluated for hot carcass weight, pH, conformation, physiological maturity, finishing, fat distribution, and length. Characteristics, such as pH, color, marbling, exudation, as well as cooking losses, percentage of ether extract, and shear force were evaluated in meat at time zero and after seven days of aging. The carcasses displayed satisfactory results for parameters such as pH at 24 h of cooling (pH24), finishing, distribution of fat, and subcutaneous fat thickness (5.58, 3.27, 2.40, and 6.62 mm, respectively). The meat had a low marbling score (5.08) and percentage of ether extract (1.71), indicating that the meat was relatively lean. Exudation and cooking losses showed similar results at zero and seven days of aging. The meat subjected to seven days of aging showed higher lightness and hue (40.98 and 0.77, respectively) and tenderness of 5.25 kg. These results indicated that aging affected meat color and shear force parameters; the meat of cross-heifers was softer but less red after maturation.

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