Ractopamine supplementation improves leanness and carcass yield, minimally affecting pork quality in immunocastrated pigs

This study was carried out to determine the combining effects of feeding up to 15 mg kg−1 ractopamine (RAC) to physically castrated (PC) pigs or those injected with an anti-GnRF vaccine (IC), on growth performance during suckling, weaning, growing and finishing phases. Out of a total of 1,160 male piglets, 50 % were surgically castrated at age 7, while 50 % underwent immunization against GnRF on the 103rd and 136th day of life. A completely randomized design, with two treatments (PC and IC), was used from the 1st until the 60th day of life. Afterwards, 792 animals, PC and IC, selected according to overall average weight (23.3 ± 0.69 kg) were allotted based on a completely randomized block design with a 2 × 4 factorial arrangement of treatments (castration categories × RAC levels) with 9 replications (11 animals) per main combination effect. IC growing pigs improved feed conversion due to lower average daily feed intake and higher average daily gain (ADG). During the finishing phase, both RAC and immunocastration increased body weight, but the effects were independent. RAC, on its own improved ADG and feed conversion. However, pigs fed 10 mg kg−1 RAC had higher blood lactate compared to those fed lower levels, suggesting that these animals were more susceptible to stress. Muscle depth was influenced only by RAC, whereas fat thickness was lower for IC. Lean meat increased and fat decreased in the shoulder and belly of IC; RAC had a positive effect on belly lean meat only. Either immunocastration or RAC inclusion (at least 5 mg kg−1) promoted muscle gain and fat reduction in pig carcass, adding value to pork

Ractopamine supplementation improves leanness and carcass yield, minimally affecting pork quality in immunocastrated pigs

ABSTRACT: This study was carried out to determine the combining effects of feeding up to 15 mg kg−1 ractopamine (RAC) to physically castrated (PC) pigs or those injected with an anti-GnRF vaccine (IC), on growth performance during suckling, weaning, growing and finishing phases. Out of a total of 1,160 male piglets, 50 % were surgically castrated at age 7, while 50 % underwent immunization against GnRF on the 103rd and 136th day of life. A completely randomized design, with two treatments (PC and IC), was used from the 1st until the 60th day of life. Afterwards, 792 animals, PC and IC, selected according to overall average weight (23.3 ± 0.69 kg) were allotted based on a completely randomized block design with a 2 × 4 factorial arrangement of treatments (castration categories × RAC levels) with 9 replications (11 animals) per main combination effect. IC growing pigs improved feed conversion due to lower average daily feed intake and higher average daily gain (ADG). During the finishing phase, both RAC and immunocastration increased body weight, but the effects were independent. RAC, on its own improved ADG and feed conversion. However, pigs fed 10 mg kg−1 RAC had higher blood lactate compared to those fed lower levels, suggesting that these animals were more susceptible to stress. Muscle depth was influenced only by RAC, whereas fat thickness was lower for IC. Lean meat increased and fat decreased in the shoulder and belly of IC; RAC had a positive effect on belly lean meat only. Either immunocastration or RAC inclusion (at least 5 mg kg−1) promoted muscle gain and fat reduction in pig carcass, adding value to pork

Effects of Ocimum basilicum Linn Essential Oil and Sodium Hexametaphosphate on the Shelf Life of Fresh Chicken Sausage

Although consumers and the food industry have an interest in reducing the use of synthetic additives, the consumption of processed meat in Brazil has been increasing because of the easy preparation and low cost. Owing to the antimicrobial and antioxidative properties of Ocimum basilicum essential oil (EO), it has potential applications in food products. Polyphosphates are already used in meat processing with the goal of improving the quality of the products. The aim of this work was to assess the effects of sodium hexametaphosphate (SHMP) and O. basilicum EO, when added separately or together, on physical, chemical, and microbiological parameters during the shelf life of chicken sausage. We also performed sensory analysis of the product prepared in this manner. Six different treatments were produced in which the substances were tested together or separately, and the content of EO was 0.3 or 0.03%. The samples were analyzed after 1, 7, and 15 days of storage at 4 degrees C. An increase in pH on days 7 and 15 in samples that contained SHMP was observed. In the samples that contained either 0.3 or 0.03% EO, coliforms were inhibited throughout the study period (P < 0.05), which was not observed in samples with EO plus SHMP, thus demonstrating that the stabilizer blocked the antibacterial action of EO. There was a reduction in the cook loss and increased compressive force in the samples with 0.5% SHMP, contributing to greater juiciness of the product. The EO had substantial impact on acceptability of samples, but it did not influence the activities already described of polyphosphate.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP