Bermuda Grass Hay or Sorghum Silage with or without Yeast Addition on Performance and Carcass Characteristics of Crossbred Young Bulls Finished in Feedlot

Abstract

This experiment was carried out to evaluate performance and carcass characteristics of 40 crossbred young bulls (Zebu×European) finished in a feedlot under two roughage sources (Bermuda grass hay or sorghum silage) with or without the addition of yeast (Saccharomyces cerevisae). The bulls were 20 months old, their initial average weight was 356 kg and they were allocated into four groups of ten animals. The experimental diets were Bermuda grass, Bermuda grass+yeast, sorghum silage and sorghum silage +yeast. Animal performance and carcass characteristics were not influenced by roughage source or yeast addition. The average daily weight gain was 1.50 kg, dry matter intake (DMI) was 11.1 kg/d, DMI as percentage of liveweight was 2.60% and feed dry matter conversion was 7.70. The mean dressing percentage was 52.0% and hot carcass weight was 268 kg. Carcass conformation was classified between good-minus to good. Carcass length (137 cm), leg length (72.9 cm) and cushion thickness (26.6 cm) were not influenced by treatments. The average fat thickness was 3.80 mm and the Longissimus muscle area was 66.9 cm 2 . The classification of color, texture and marbling were slightly dark red to red, fine and slight-minus to light-typical, respectively. The mean percentage of bone, muscle and fat in the carcass was 15.5%, 62.3% and 22.5%, respectively. Yeast addition increased γ-linolenic fatty acid (0.15 vs. 0.11%) deposition. Bermuda grass hay increased deposition of α-linolenic (0.49 vs. 0.41%), arachidonic (2.30 vs. 1.57%), eicosapentaenoic (0.41 vs. 0.29%), docosapentaenoic (0.80 vs. 0.62%), docosahexaenoic (0.11 vs. 0.06%) and n-3 fatty acids, and reduced n-6: n-3 ratio in meat, when compared to sorghum silage treatments. The treatments had no effect on saturated fatty acids (49.5%), polyunsaturated fatty acids (11.8%), n-6 fatty acids (9.87%), n-3 (1.61%) and PUFA:SFA ratio (0.24). Monounsaturated fatty acid levels were higher on sorghum silage (40.7 vs. 37.7%). The addition of yeast caused higher n-6: n-3 ratio (7.28 vs. 5.70) than treatments without yeast.

Meat quality from four genetic groups of bulls slaughtered at 14 months old

“…According to Müller's scale (1980), the color for all genetic groups may be considered satisfactory, as they The mean rates of moisture, ashes and crude protein were 72.8, 1.03 and 22.7%, respectively. These results were similar to those found by Ducatti et al (2009) who evaluated chemical and fatty acids composition of different genetic groups (Purunã 1 st generation; Purunã 2 nd generation; Caracu; Canchin vs. Angus and Charolês vs. Caracu) and the mean values observed were 73.3, 0.97% and 22.5%, respectively. According to these results, moisture, ashes and crude protein rates did not show any variations owing to the genetic groups.…”

“…According to these results, moisture, ashes and crude protein rates did not show any variations owing to the genetic groups. However, total lipids and total cholesterol rates reported by Ducatti et al (2009) were higher (2.16% and 42.0 mg 100 g -1 of muscle) than those in current analysis (1.37% and 36.6 mg 100 g -1 of muscle). Kazama et al (2008);Rotta et al (2009a and b) also reported higher total cholesterol rates when compared to those in current experiment.…”

“…According Perotto et al (2000), weight increase and better quality carcass are the benefits that crossbreeds between Bos taurus taurus and Bos taurus indicus provide to beef cattle. Since cattle breed is one of the most important factors for fat deposition and composition (MAGGIONI et al, 2009(MAGGIONI et al, , 2010PRADO et al, 2008dPRADO et al, , 2009bROTTA et al, 2009a and b) it should be understood due toits genetic transmission. However, the variation's detailed mechanisms and whether or how they may be manipulated are still not clearly known.…”

Feeding propolis or essential oils (cashew and castor) to bulls: performance, digestibility, and blood cell counts

“…Thus, due to increases in the consumption of beef and the demand for quality products by consumers in Brazil, finishing cattle in feedlots may be a tool to maximize production and improve meat quality (Prado et al ., 2008;Rotta et al ., 2009). In Brazil, bulls are finished in feedlots when they reach 380 Kg body weight (BW) at about 24 months of age (Maggioni et al ., 2009;. There has been an increase in using feedlot systems for finishing young bulls at 18 months (Dian et al ., 2010;Ito et al ., 2010) and bulls after weaning at 10 and 12 months of age (Ito et al ., 2012).…”

Sodium monensin or propolis extract in the diet of Nellore bulls finished in feedlot: chemical composition and fatty acid profile of Longissimus muscle

“…The meat has important nutritional function on human diet by proteins with high quality (WEBB; O'NEIL, 2008), essential fatty acids (MOREIRA et al, 2003;KAZAMA et al, 2008;MACEDO et al, 2008;MAGGIONI et al, 2009;ROTTA et al, 2009a;, minerals and complex B vitamins. However, the consumption of red meat has been associated with health problems (cardio diseases, obesity, hypertension and cancers, WOOD et al, 2004) by presence of saturated fatty acids and cholesterol (KAZAMA et al, 2008;PRADO et al, 2009a;2009c).…”