Energy metabolism and respirometry of lambs fed sun or shade dried hays of banana crop residues.

We aimed to evaluate the effects of different drying methods for banana residues on the energy metabolism and respirometry of growing lambs. Twenty Santa Inês x Dorper lambs were fed five experimental diets: Tifton 85 grass hay (Control), shade-dried banana leaf hay (LH Shade), shade-dried pseudostem banana hay (PH Shade), sun-dried banana leaf hay (LH Sun), and sun-dried banana pseudostem hay (PH Sun). Nutrient intake and digestibility were assessed in metabolic cages, whereas O2 consumption and CO2, methane, and heat production were measured in a respirometry chamber with animals fed at maintenance and ad libitum levels. Nutrient and energy intake was not influenced by diet. Pseudostem hay had higher apparent digestibility of dry matter (71.5%), organic matter (72.4%), and neutral detergent fiber (58.0%). However, this led to greater energy loss in the form of methane (12.1%). The banana residue hays and drying methods did not alter oxygen consumption, CO2 production, or heat production of animals fed ad libitum or during maintenance. On the other hand, the use of leaf hay resulted in a reduction of 24.7% in enteric methane production of animals fed ad libitum. The inclusion of pseudostem hay is recommended in sheep feedlot diet. This residue provided greater use of DM, however promoted a greater loss of energy in the form of methane, resulting in similar energy consumption. The drying methods did not reduce the availability of nutrients and the sun drying method is recommended, since it is a faster drying method.

Does macauba cake alter nutrient digestibility and microorganism population in the rumen of sheep?

Twenty Santa Inês male sheep were used in a randomized block design to evaluate the effects of different levels of macauba cake (MC) on nutrient digestibility and the population of microorganism in the rumen. The animals were divided into four groups according to MC levels (0, 10, 20, and 30% of DM) and initial body weight ranging from 32.75 to 52.17 kg. Diets were isonitrogenous and formulated to attend metabolizable energy requirements, and feed intake was regulated with 10% allowance for leftovers. Each experimental period lasted 20 days, with the final 5 days reserved for sample collection. Macauba cake inclusion did not affect the dry matter, organic matter, or crude protein intake but increased the ether extract, neutral detergent fiber, and acid detergent fiber intake, mainly because of changes in the concentrations of these components in diets with a higher level of MC. With MC inclusion, a linear decreasing effect was observed for the dry matter and organic matter digestibility, and a quadratic effect with a maximum point of 21.5% was observed for the acid detergent fiber digestibility. A relative reduction of 73% in anaerobic fungal populations was observed with the lowest level of MC inclusion, and a relative increase of 162% in methanogenic populations was observed with the highest level of MC inclusion. The increasing level of macauba cake up to 30% of the diet of lambs reduced the dry matter digestibility and reduced anaerobic fungi but increased methanogenic population.

Acceptability by sensory and visual analyses of meat from Nellore heifers fed with natural additives and finished in feedlots.

BACKGROUND: This study evaluated the acceptability (by sensorial and visual analyses) of meat from 40 Nellore heifers (finished in feedlots for 73 days) fed with different diets supplemented with essential oils (EOs) and an active principle blend. The five diets tested were: CON - a diet without essential oil and active principle blend (eugenol, thymol, and vanillin); ROS - a diet supplemented with rosemary EO; BLE - supplemented with a blend; BCL - a diet with clove EO+ blend; and BRC - a diet with rosemary, clove EOs + blend. The acceptability of diet and aging time was evaluated by consumers. RESULTS: Diet affected consumer acceptability and visual analysis (meat color). The diets with EO and the blend showed better sensory acceptance by the consumers; meat aged for 7 days received higher scores than meat aged for 1 day. Meat from heifers that received both EOs + blend (BCL, BRC) obtained the highest scores in the visual evaluation. CONCLUSION: The use of natural compounds in ruminant diets improves the sensory characteristics of meat without damaging visual acceptability and may be an alternative to the conventional additive market. © 2020 Society of Chemical Industry.

Physicochemical characteristics of dry aged beef from younger Nellore bulls slaughtered at different body weights.

Reducing slaughter age can improve meat quality and reduce costs, while an ageing process can result in more standardized products. Thus, the objective of this paper was to measure the physicochemical characteristics of dry aged meat from younger Nellore bulls slaughtered at different body weights. Twenty-four Longissimus thoracis from young bulls (14 months of age) finished in a feedlot at body weights of 350, 400 and 450 kg were used. From each group (N = 8), samples were divided into three portions for 0, 14 and 28 days of dry ageing. After the samples reached their dry aged period weight, pH and colour were measured. Next, water losses, shear force, the chemical composition and the fatty acids profile of the meat were measured. Reducing slaughter weight (350 kg) of young bulls did not affect meat tenderness but increased saturated fatty acids contents at day 1 of dry ageing. During the dry ageing process, drip loss increased, but thawing losses were reduced. Colour parameter was reduced by dry ageing and meat becomes darker, but meat tenderness was increased. Dry ageing increased the ash content. Dry ageing increased saturated fatty acid and reduced the monounsaturated and saturated fatty acid ratio (MUFA/SFA), but did not change the polyunsaturated fatty acids. Nellore young bulls (14 months) can be slaughtered with 400 or 450 kg without compromising physicochemical characteristics, while dry ageing improved meat tenderness but increased saturated fatty acids and changed meat colour.

Carcass Composition and Cuts of Bulls and Steers Fed with Three Concentrate Levels in the Diets.

In this paper, weight, carcass dressing, weights of the primary cuts, weights of the physical components of the primary cuts, and weights of the main commercial cuts of 66 Purunã animals, of which 33 were bulls and 33 were steers were evaluated. These animals, with an average age of 19 months at the beginning of the experiment, were finished in a feedlot system during 116 days, and were fed with diets containing three levels of concentrate (0.8%, 1.1%, and 1.4% of body weight). The concentrate was formulated with 25% soybean meal, 73% ground corn grain, 1% of a mineral mix, and 1% of limestone. The interaction between sexual groups and the concentrate level was not significant for any of the variables. Likewise, no effect of the concentrate level was detected on the same variable traits. The bulls demonstrated higher hot carcass weights (265.1 vs 221.7 kg) and a higher proportion of forequarter (38.4% vs 36.1%) however the steers presented with higher proportions of side (19.7% vs 18.5%) and hindquarter (44.2% vs 43.1%). The bulls produced higher yields of muscle in the three primary cuts, there by resulting in higher yields of edible portions of the carcass. The bulls also produced higher weights of tenderloin, knuckle, topside, flat, eye round, rump, and rump cover. The finishing of young bulls in feedlot is to be recommended, since the animals produce carcasses with higher amounts of edible meat and higher yields of commercial cuts, thus allowing for a better price for the carcass. Low concentrate level could be used due to the lower cost of production for farmers.

Animal Performance and Carcass Characteristics of Bulls (1/2 Purunã vs 1/2 Canchim) Slaughtered at 16 and 22 Months Old, and Three Different Weights.

Current study aimed to evaluate the performance of bulls (1/2 Purunã vs 1/2 Canchim) slaughtered at two ages and three different weights. One hundred and thirteen bulls were divided into two slaughter ages (16 and 22 months) and three different slaughter weights (light, 422 kg; medium, 470 kg; and heavy, 550 kg). The body weight was higher for bulls slaughtered at 16 months. Daily gain, carcass weight and dressing were higher for bulls slaughtered at 16 months. Feed intake was higher for bulls slaughtered at 22 months although feed efficiency was better for bulls slaughtered at 16 months. Carcass characteristics were better for bulls slaughtered at 16 months. The percentages of muscle, fat and bone and meat characteristics were similar between two slaughter ages. Feed intake and animal performance was lower for lighter animals. Feed conversion and carcass dressing were similar in the three slaughter weights. Muscle percentage was higher for heavier animals but fat and bone percentages were lower. Slaughter weight had no effect on meat characteristics.

Meat quality of young bulls finished in a feedlot and supplemented with clove or cinnamon essential oils.

Forty young crossbred bulls (10 ± 2.2 months of age; 219 ± 11.7 kg) were finished in a feedlot with one of five different treatments: CON, control (no essential oil); CLO450, clove essential oil (450 mg/kg); CLO880, clove essential oil (880 mg/kg); CIN450; cinnamon essential oil (450 mg/kg); and CIN880, cinnamon essential oil (880 mg/kg). Instrumental meat quality attributes and consumer acceptability aspects (visual and sensory) were assessed during meat ageing and display. The inclusion of clove essential oil showed (P = 0.033) a quadratic effect on lipid oxidation in meat evaluated under display conditions. Level of cinnamon essential oil affected (P < 0.05) pH, shear force, and meat colour. On the other hand, the diet had no effect (P > 0.05) on sensory or visual acceptability. Ageing (7 days) enhanced (P < 0.05) sensory acceptability attributes. Globally, the addition of essential oil in bull diets can be an alternative to reduces lipid oxidation without modifying sensory acceptability attributes.

Improvements in the quality of meat from beef cattle fed natural additives.

Forty young bulls were fed with five different treatments (n = 8, 62 days): control, without the addition of natural additives (CON); NA15, a mixture of natural additives (1.5 g/animal/day); NA30, a mixture of natural additives (3.0 g/animal/day); NA45, a mixture of natural additives (4.5 g/animal/day); and NA60, a mixture of natural additives (6.0 g/animal/day). The hot carcass weight and dressing percentage, fat thickness, Longissimus muscle area, marbling, pH, and carcass tissue composition were measured. In addition, the instrumental meat quality (colour, water holding capacity, texture and lipid oxidation) and consumer acceptability attributes, across display were evaluated. Diet had no effect (P > .05) on the carcass characteristics evaluated (except pH). The diets significantly influenced the pH, shear force, tenderness, lipid oxidation and overall acceptability evaluated by consumers (P < .05). Globally, natural additives have some potential use in animal feed to improve meat quality.

Sensorial, color, lipid oxidation, and visual acceptability of dry-aged beef from young bulls with different fat thickness.

The reduction in slaughter age with minimum fat and dry aging process improves meat tenderness, however, its shelf-life in display has not been studied. It was evaluated the sensorial, and the color, lipid oxidation, and visual acceptance in display of dry-aged beef (0, 14, and 28 days) from young bulls slaughtered with different subcutaneous fat thickness (2.00, 3.00, and 4.00 mm). Meat with 2.00 and 3.00 mm fat had higher acceptability than 4.00 mm (p < .05). Dry aging improved overall acceptability of consumers. Meat with 2.00 and 3.00 mm fat presented higher lightness and lipid oxidation values than 4.00 mm (p < .05) but similar visual acceptance was observed. Dry-aged beef (14 and 28 days) had lower lightness, but higher redness (p < .05) than not dry aged (0 days). Display reduced color over time, for all dry-aged treatments (p < .05). Dry aging process increased lipid oxidation but these values were below 2.00 mg/kg of malonaldehyde only in the first day of display. Dry aged for 14 days had similar visual acceptability to not dry-aged beef until the third day of display (p < .05). Shelf-life of 0, 14, and 28 days of dry aged was 5.41, 2.55, and 0.23 days. Despite of the increase in lipid oxidation and lightness, the sensorial and display acceptability of meat from young bulls was not prejudiced by the reduction in fat thickness. Beef dry-aged for 14 days was visually well accepted and could be displayed for 2.55 days without compromising acceptability.

Number of consumers and days of display necessary for the assessment of meat colour acceptability.

Visual assessment is regarded as the gold standard to evaluate meat colour shelf-life, but it is costly and time consuming. To address this issue, this paper aims to evaluate the number of consumers and days of display that are necessaries in order to assess the colour shelf-life of meat, presented with different methods, all using images. Photographs of thirty-six lamb steaks were taken just after cutting (day 0) and on each of the following days until the 14th day of display under standardized conditions. Images were presented in three different manners: 1) with days of display and animals in random order (Random); 2) days of display in sequential and animals in random order (Sequential); and, 3) days of display and animals in sequential order (Animal); they were presented to 211 consumers who evaluated visual acceptability on a 9-point scale. At day zero, visual acceptability scores were the highest in Animal, followed by Sequential, and then by the Random (P < .05) method. Scores decreased over time for all methods tested (P < .05). The Random method presented the highest standard deviation; however, an increase in standard deviation among consumers along days of display was observed for all methods tested (P < .05). Shelf-life determined by regression varied according to the method of presentation (7.83, 7.00 and 7.54 days for Random, Sequential and Animal, respectively). A minimum number of 4 day points before and 4 day points after neutral scores had been reached (scores = 5.0) were necessary in order to obtain a robust model. The minimum number of required consumers (α = 0.05; d = 0.1 and ß = 0.2 or 0.1) varied according to methodology: it was 81 to 109 consumers for Random, 69 to 92 for Sequential, and 55 to 74 for Animal. Our study indicates that an optimal number of days and evaluators can be calculated depending on the manner of sample presentation. These findings should be taken into account in further studies that aim to balance data reliability with the cost involved in meat colour analyses.

Validation of photographs usage to evaluate meat visual acceptability of young bulls finished in feedlot fed with or without essential oils.

Forty ½ Brown Swiss×½ Nellore crossbred bulls were distributed into three experimental groups: CON - diet without addition of essential oils; CLO - diet with average 5,000mg/animal/day of clove essential oils and CIN - diet with average 5,000mg/animal/day of cinnamon essential oils to evaluate three methodologies of visual acceptability: with steaks directly in Trays and Sequential and Random photos. Seventeen consumers evaluated visual appearance of meat using a 9-point structured hedonic scale. CON group presented higher shelf-life than essential oils groups. Trays and Sequential scores were similar in the majority of days; thus digital images could be used to evaluate colour evolution. However, Random photos resulted in lower scores and slower acceptability decrease than Trays and Sequential photos (p<0.05) among the second and fifth day of display. Random photos presented a lower and more constant standard deviation than Trays and Sequential photos (p<0.01) indicating that this methodology promoted a higher standard situation for meat colour evaluation.