Banca de DEFESA: FÁBIO SANTOS DO NASCIMENTO

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : FÁBIO SANTOS DO NASCIMENTO
DATE: 28/02/2023
TIME: 14:00
LOCAL: Departamento de Zootecnia e remota
TITLE:

UREA-CACTUS CLADODES ASSOCIATION MEXICAN ELEPHANT EAR (Opuntia stricta Hall) IN THE FEEDING OF SHEEP

KEY WORDS:

cactus cladodes

meat quality

non-protein nitrogen

weight gain

small ruminants

PAGES: 93
BIG AREA: Ciências Agrárias
AREA: Zootecnia
SUBÁREA: Nutrição e Alimentação Animal
SPECIALTY: Avaliação de Alimentos para Animais
SUMMARY:

 

 

 

ABSTRACT

The objective of this study was to evaluate diets based on Orelha de Elefante Mexicana spineless cactus (Opuntia stricta Haw) (OEM) with increasing levels of urea in replacement of soybean meal on intake and digestibility of dry matter and its constituents, nitrogen balance, blood metabolites, performance, characteristics and composition of the carcass, physicochemical composition, quality and sensorial attributes of feedlot Santa Inês sheep meat. Forty non-castrated Santa Inês lambs, with initial body weight of 22.2 ± 2.1 kg, were distributed in a completely randomized design, with four treatments and ten replications. The treatments consisted of four diets based on palm oil associated with increasing levels of urea (0; 7.3; 14.6 and 21.9 g/kg DM) replacing soybean meal. Increasing levels of urea in diets based on OEM cactus were not influence (P > 0.05) intake of DM, OM, acpNDF, TDN (g/day) and DM (%BW^-0.75), but increased linearly (P = 0.0347) the intake of DM (%BW), the intake (g/day) of CP (P = 0.0182), EE (P = 0.0003) and NFC (P = 0.0280), without influencing (P > 0.05) the apparent digestibility coefficients of DM, OM, CP, EE, acpNDF and NFC. The amounts of ingested N, fecal N, absorbed N (g/day) or retained N and absorbed N (% ingested) were not influenced, but urinary N (g/day), and retained N (% ingested) were quadratically influenced (P = 0.0091 and P = 0.0003) with maximum values (9.5 and 44.5 g/day) in levels (7.3 and 21.9 g/kg DM) of urea respectively. Plasma glucose, and concentrations of total cholesterol, total proteins, creatinine, urea, uric acid, liver enzymes AST, ALT, lipase and the concentrations of minerals P, Mg, Na and the Ca:P ratio were not influenced (P >0.05). However, triglycerides and albumin concentrations were quadratically influenced (P = 0.0033 and P = 0.0148) with maximum values (22.4 and 2.9 g/dL) observed at levels (14.6 and 0. 0 g/kg DM) of urea respectively. The concentrations of lactate, GGT (P < 0.0001), FA (P = 0.0127) and Ca (P < 0.0204) and K (P < 0.0020) concentrations increased linearly (P < 0.0001). The performance, body weight at slaughter, total weight gain and average daily gain decreased linearly (P = 0.0288, P = 0.0034, P = 0.0033) respectively, while feed conversion increased linearly (P = 0.0003). Empty body weight (P = 0.0089), hot carcass weight (P = 0.0230) and cold carcass weight (P = 0.0145) decreased linearly. However, the contents of the gastrointestinal tract, hot carcass yield, cold carcass yield, biological yield, chilling losses, subcutaneous fat thickness, loin eye area, carcass compactness index, leg compactness index, Carcass conformation and finishing fat were not influenced (P > 0.05). However, perirenal fat was quadratically influenced (P < 0.0025), with maximum fat indices (2.20) on levels (0 and 21.9 g/kg DM) of urea, heart weight and amount of inguinal fat were not influenced (P > 0.05), but linearly affected the weight of the liver (P = 0.0298), lungs + trachea (P = 0.0020) and kidneys (P = 0.0014), while the spleen weight (P = 0.0315), mesenteric fat (P = 0.0212), omental fat (P < 0.0001), perirenal fat (P < 0.0001), were influenced quadratically with maximum weights (0.083; 0.352; 0.656 and 0.341 kg), at levels (7.3; 21.9; 21.9 and 0.0 g/kg DM) of urea in the diet, respectively. The commercial meat cuts, the weights of the neck, shoulder, ribs, saw and loin, in addition to the neck, ribs, saw and leg yields were not influenced (P > 0.05). Leg weight ((P = 0.0373) and loin yield (P = 0.0266) decreased linearly, while shoulder yield was quadratically influenced (P = 0.0237) with higher yield (20.20 %) at the level (14.6 g/kg DM) of urea. Regarding the tissue composition of the leg, the weight of the reconstituted leg, weight of the total muscles, weight of the Semimembranosus muscles, Biceps femoris, Quadriceps femoris, other muscles, femur weight, weight of subcutaneous fat, intermuscular fat and total fat, as well as, weight of other tissues, yields of muscle, fat, other tissues, muscle/fat ratio and femur length were not influenced (P > 0.05) by urea levels. The weight of the Semitendinosus muscle (P = 0.0357), Adductor muscle (P = 0.0230), weight of the 5 leg muscles (P = 0.0177) and leg muscularity index (P = 0.0188) decreased linearly. In addition, bone weight, bone yield, muscle/bone ratio were quadratically influenced (P = 0.0474, P = 0.0064, P = 0.0143) with maximum values (552 g, 20.69%, 3.5) in the levels (14.6; 7.3; 21.9) of urea respectively. The parameters evaluated in the meat, pH, water holding capacity, color parameters (L*, a*, b*), moisture content, CP and ash were not influenced (P > 0.05). However, cooking loss (P = 0.002) and shear force (P = 0.044) decreased linearly, while the ether stratum content increased linearly (P = 0.047). There was no difference (P > 0.05) for meat sensory attributes such as general appearance, color, aroma, tenderness, juiciness and flavor. Orelha de Elefante Mexicana spineless cactus based diets, can partially or completely replace soybean meal in the diet of feedlot lambs without without changing dry matter intake, total digestible nutrient intake, apparent dry matter and nutrient digestibility, obtaining a positive N balance, not compromising the characteristics and carcass yield, in addition to improving the qualitative characteristics of the meat without interfering with sensory attributes. However, it reduces performance and increases feed conversion.

 

 

COMMITTEE MEMBERS:
Presidente - FRANCISCO FERNANDO RAMOS DE CARVALHO
Interna - ANTONIA SHERLANEA CHAVES VERAS
Externo à Instituição - LEÍLSON ROCHA BEZERRA - UFCG
Externo à Instituição - DANIEL BARROS CARDOSO - UFRPE
Externo à Instituição - DORGIVAL MORAIS DE LIMA JUNIOR - UFERSA