RESUMO

The objective of this study was to evaluate the effects of 2 Mexican oregano essential oils (MOO), from Poliomintha longiflora Gray (PLG) and Lippia berlandieri Schauer (LBS), in drinking water (DWt) on the performance, slaughter variables, and meat quality of broilers over a 40 D period of growth. A total of 180 non-sexed Ross-308 broilers (1-day-old) were randomly assigned to 3 treatments with 6 replications each (10 birds per replicate): CON = DWt control (without MOO); PLG = DWt + 400 mg/L of PLG; and LBS = DWt + 400 mg/L of LBS. The CON, PLG, and LBS broilers body weights were similar (P > 0.05) at all times. Feed intake (FI) was different by treatment (P < 0.05) at 7 and 28 D, and water intake (WI) was different (P < 0.05) at day 28. The CON treatment was highest (P < 0.05) at 28 D for FI and WI, whereas LBS was lowest (P < 0.05). Weight gain (WG) for CON, PLG, and LBS broilers was similar (P > 0.05), although WG for CON was slightly higher. In CON broilers, slaughter weight was highest (P < 0.05), but thigh yield was lowest (P < 0.05). The CON and PLG treatments were lower (P < 0.05) in thigh and leg cooking losses. The PLG treatment presented the highest values (P < 0.05) for breast-meat redness, saturation index, shear force, odor, taste, and overall sensory acceptability. The LBS was higher (P < 0.05) for breast-meat shear force, cohesiveness and resilience, but lower (P < 0.05) for sensory attributes. Mexican oregano essential oils at 400 mg/L can serve as natural alternative additives in DWt to improve broiler production and meat quality.

Assuntos

RESUMO

The objective of this study was to evaluate the effect of oral administration of glycerol, as a source of energy, to steers 24 h before slaughter on biochemical indicators of physiological and oxidative stress. Fifty Zebu x Swiss-or Simental-cross steers were selected at random at the finalizing stage impending slaughter. Blood samples were collected from the jugular vein before administering the treatments and 24 h afterward. After sacrifice, samples of the Longissimus dorsi muscle were collected. Biochemical indicators evaluated in bovine serum were hematocrit (VGA), lactate dehydrogenase (LDH), lactate (LAC), cortisol (COR), glucose (GLU), β-hydroxybutyrate (BHT), creatine kinase enzyme (CK), free non-esterified fatty acids (NEFA), antioxidant activity (FRAP), thiobarbituric acid reactive substances (TBARS), and glutathione peroxidase reaction (GSH-Px). The variables evaluated in meat were TBARS, FRAP, pH, texture and shelf life. Analysis of the stress biomarkers evaluated in bovine serum did not reveal differences (P>0.05) between treatments T0 and T1 for the variables COR, VGA, GLU, NEFA, BHT or CK. There were, however, differences between sampling times for the variables FRAP (P = 0.021) and GSH (P = 0.006). The indicators FRAP and TBARS in the sampled meat were not different (P>0.05) between treatments. Meat pH changed over time (P=0.0002), but not its texture (P>0.05). It is concluded that the administration of glycerol as an energy supplement 24 h before sacrifice did not modify the balance of physiological constants of the evaluated steers, nor did it produce significant changes in shelf life of meat.(AU)

Assuntos

RESUMO

The objective of this study was to evaluate the effect of oral administration of glycerol, as a source of energy, to steers 24 h before slaughter on biochemical indicators of physiological and oxidative stress. Fifty Zebu x Swiss-or Simental-cross steers were selected at random at the finalizing stage impending slaughter. Blood samples were collected from the jugular vein before administering the treatments and 24 h afterward. After sacrifice, samples of the Longissimus dorsi muscle were collected. Biochemical indicators evaluated in bovine serum were hematocrit (VGA), lactate dehydrogenase (LDH), lactate (LAC), cortisol (COR), glucose (GLU), β-hydroxybutyrate (BHT), creatine kinase enzyme (CK), free non-esterified fatty acids (NEFA), antioxidant activity (FRAP), thiobarbituric acid reactive substances (TBARS), and glutathione peroxidase reaction (GSH-Px). The variables evaluated in meat were TBARS, FRAP, pH, texture and shelf life. Analysis of the stress biomarkers evaluated in bovine serum did not reveal differences (P>0.05) between treatments T0 and T1 for the variables COR, VGA, GLU, NEFA, BHT or CK. There were, however, differences between sampling times for the variables FRAP (P = 0.021) and GSH (P = 0.006). The indicators FRAP and TBARS in the sampled meat were not different (P>0.05) between treatments. Meat pH changed over time (P=0.0002), but not its texture (P>0.05). It is concluded that the administration of glycerol as an energy supplement 24 h before sacrifice did not modify the balance of physiological constants of the evaluated steers, nor did it produce significant changes in shelf life of meat.

Assuntos

RESUMO

Se evaluó el efecto de la suplementación de lisina en dietas para cerdos en iniciación sobre ganancia de peso y características de la canal y cárnicas. Se utilizaron 18 cerdos castrados (Yorkshire, Hampshire, Duroc y Landrace) con peso vivo inicial promedio de 10,13 kg y 40 días de edad. Se asignaron en tres tratamientos (T) con 6 repeticiones cada uno. El testigo (T1) fue dieta basal sin lisina adicionada; T2 = T1 + 0,285 kg de L-lisina/100 kg de alimento, y T3 = T1 + 0,569 kg de lisina/100 kg de alimento. Los cerdos se alimentaron por 33 d. La dieta basal fue de sorgo, (Sorghum vulgare) y pasta de soya, (Glicine max) (20,81% de PC y 3.460 Mcal EM/kg de MS). Al final del período de alimentación se registró el peso de los animales, la altura a la cruz (cm), circunferencia torácica (cm), espesor de grasa dorsal medida con ultrasonido. Para las características de la canal y cárnicas se sacrificaron al azar cuatro animales por tratamiento. Para muestras de costilla, jamón y paleta de cada canal se analizó para MS, PC, grasa y cenizas. No se encontró diferencias (P³0,05) entre tratamientos para ganancia de peso, altura a la cruz, circunferencia torácica, y grasa dorsal (mm). Para peso al sacrificio, rendimiento de la canal caliente y fría, área del ojo de la costilla, contenido de MS, PC, grasa y cenizas de costilla, jamón y paleta fueron similares (P³0,05) entre tratamientos. Se concluye que la lisina como promotor de crecimiento de tejido magro no se reflejó en ganancia de peso, características de la canal o composición de la carne de los cerdos en iniciación.

The effect of lysine supplementation in diets for growing pigs on weight gain, carcass and meat characteristics was evaluated. Eighteen castrated pigs (Yorkshire, Hampshire, Duroc y Landrace) of 10.13 kg initial weight and 40 d of T2 = T1 + 0.285 kg of lysine / 100 kg of feed; and T3 = T1 + 0.569100 kg of feed. Basal diet contained 20.81% CP and 3,460 Mcal/kg of ME. Pigs were fed for 33 d. At the end of the feeding trial final weight, cross height (cm) and thoracic circumference (cm), and subcutaneous fat measured with ultrasound were recorded. For carcass and meat characteristics, four pigs per treatment selected at random were slaughtered. Samples of rib, ham and shoulder from each carcass were analyzed for DM, CP, fat and ash. There were no differences (P>0.05) between treatments for weight gain, cross height, thoracic circumference, weight at sacrifice, hot and cold carcass yields, rib eye area and subcutaneous fat. The content of DM, CP, fat and ash was similar (P>0.05) among treatments. It is concluded that lysine as growth promotant of lean tissue was no reflected in weight gain, carcass characteristics or meat composition of the growing pigs.