Risk factors associated with pig pre-slaughtering losses.

The incidence of non-ambulatory non-injured (NANI), non-ambulatory injured (NAI) and dead pigs on-arrival at three Brazilian slaughterhouses were evaluated in 37,962 pigs to identify risk factors linked to them, besides carcass bruises and limb fractures. Total pre-slaughtering losses were 1.18%, in which NAI (0.39%) and NANI (0.37%) incidences contributed the most. A positive relation between on farm steeper ramp slope >20° and the incidence of NAI, NANI and dead pigs at unloading was found. Farm size, pigs/pen, enthalpy at loading, transportation time, truck loading order, muscle thickness and carcass weight, were identified as risk factors for pre-slaughtering losses. Loading procedures influenced the occurrence of limb fractures and bruises (which are a welfare issue and should be reduced). Therefore, personal training on pre-slaughter handling is essential to reduce the risk factors to improve animal welfare and avoid losses during the pre-slaughter process.

How do season, on-farm fasting interval and lairage period affect swine welfare, carcass and meat quality traits?

This study was carried out in order to determine the effects of different combinations of on-farm fasting intervals (8, 12, 16, 20 h) and 1.5 h of transport plus lairage periods (1, 3, 6 h) at different seasons (summer/winter) on blood stress parameters (cortisol and lactate), stomach content and weight, skin lesion and meat quality in a total of 960 pigs from eight farms. Blood lactate levels were greater in the summer (P < 0.001) and stomach content was affected (P < 0.05) by season, on-farm fasting interval (P < 0.001), lairage time (P < 0.0001). Stomach content weight reduces as the total feed withdrawal time increases up to on-farm fasting of 17 and 1 h of lairage. Stomach content can be influenced by feed and water in different ways according to treatments. Only 8 h of on-farm fasting is not enough to empty stomachs from feed content. However, an on-farm fasting period of 16 h or longer can also increase the occurrence of more water in the stomachs. Carcass lesions caused by fighting were greater (P ≤ 0.005) in the winter, mainly after 3 and 6 h of lairage (P ≤ 0.005). Loin and ham pHu was lower (P ≤ 0.05) for pigs slaughtered after 6 h of lairage during the summer. The application of 12 h of on-farm fasting with 6 h of lairage seemed to be best combination to reduce stomach content weight (feed and water). In the winter, shorter lairage period can be used to reduce percentage of skin lesions and better pork quality traits in pigs.

Efficacy of energy supplementation on growth performance and immune response of suckling pigs.

Three studies were performed to determine the effects of oral energy sources on the performance, immune status, and intestinal morphology of piglets. In Exp. 1, 50 litters were selected based on genotype and parity order to determine the optimum amount of supplemental energy for neonatal pigs. They were distributed according to a 5 × 5 Latin square design, in which columns were represented by 5 sows and rows were represented by 5 newborn weight categories. Treatments consisted of 2 oral doses of 0, 2, 4, 8, or 16 mL of rice bran oil (RBO). There was a positive response of RBO on BW with a numerical difference (P = 0.12) and a significant linear effect (P = 0.04) at weaning. In Exp. 2, litters (n = 340) were randomly allotted to a 2 × 2 factorial arrangement of treatments: RBO supplemented either through oral doses (without supplementation or with 2 mL of RBO) or through prestarter feed (without supplementation or with 2% of RBO replacing 2% of soybean oil). Piglets orally receiving RBO showed a numerical increase in BW at weaning (P = 0.101) compared with the control group. Moreover, piglets supplemented by prestarter feed tended to increase feed intake (P = 0.084). In Exp. 3, litters (n = 245) were selected based on genotype and parity order and they were distributed according to a 7 × 7 Latin square design planed in the same way as in Exp. 1. Each neonatal pig within a litter was randomly assigned to 1 of 7 treatments: 1) control (no supplementation), 2) 2 mL of RBO enriched with omega-3 fatty acids, 3) 2.33 mL of pure glycerin, 4) 1.3 mL of soybean oil, 5) 1.4 mL of linseed oil, 6) 1.68 mL of coconut oil, and 7) 2 mL of RBO. Animal performance was analyzed using 2 data sets: all data (average initial BW of 1.479 kg) and low birth weight (LBW) piglet data (≤1.220 kg initial BW with average of 0.985 kg). Body weight or BW gain (BWG) were not different among treatments (P > 0.10) when all data were analyzed. However, LBW piglets fed coconut oil tended to increase BW (P = 0.099) during the first week. In conclusion, the oral use of RBO may increase BW at weaning and the supplementation by prestarter feed may enhance the feed intake of piglets. In addition, coconut oil may increase BW of LBW piglets in the first week of life without affecting mortality, immune response, or gut morphology. The routine practice of oral supplementation of energy for newborn pigs could be an important tool in swine production.

Ractopamine analysis in pig kidney, liver and lungs: A validation of the method scope extension using QuEChERS as a sample preparation step.

Ractopamine has been allowed by some countries as a repartitioning additive in pig diet, since it promotes protein synthesis and fat lipolysis. Most regulatory agencies only propose the ractopamine assessment in meat, kidney, liver and fat. Aiming at contributing to the scarcity data regarding this analyte in pig lungs, we extended the scope of a LC-MS method to evaluate pig offals. Homogenized tissue samples were extracted by a QuEChERS procedure; following by clean up steps and further tandem mass spectrometry determination. Method performance was evaluated through specificity, recovery, linearity, reproducibility, repeatability, decision limit (CCα), and detection capability (CCß), in accordance to the Commission Decision 2002/657/EC. Regression coefficients (R2) between 0.994 and 0.999 were achieved for kidney, liver and lungs. Recoveries ranged from 92.0 to 127%. CCα and CCß values ranged from 3.65 to 4.86 µg kg-1, and from 6.27 to 7.21 µg kg-1, respectively. These values were under the maximum residue limits suggested by Codex Alimentarius, which are 90 and 40 µg kg-1 for kidney and liver, respectively. When applied to real samples up to 22.5, 92 and 1003 µg kg-1 of ractopamine residues were detected in pig liver, kidney and lungs, respectively. The results allowed concluding that the proposed analytical method is capable to detect ractopamine residues in all evaluated matrices. Therefore, it can be successfully applied and used as a routine method in laboratories of residue analysis.