Relationship of Transport Distance, Sex on Live Weight Loss of Pigs during Transit to Slaughter House

The transport distance have a significant impact on the levels of stress burden on animals before slaughter and have an impact on veterinary decision-making about meat edibility and also on the quality of slaughtered animal meat. The objective of the study was to determine live weight, dress weight and body weight loss during transportation of different sex group of pigs into the Slaughtering house. The body weight loss during pre-slaughter treatment of animals was recorded and carcass value traits were assessed in details. Relationship between pig live weight and dress weight was reported as dress weight = 1.06 + 0. 73 live weight. There were significant effect of sex and transport distance on live weight at slaughter, carcass weights and dressing percentage (p<0.01). Pigs given the short transport (4 Km) lost 23.01 % and pigs given the long transport (90 Km) 29.37% of their initial live weight. Overall, dressing percentage was negatively correlated with the percentage loss of live weight in transport (P<0.01). As conclusion, long transportation of the pigs is a great stress factor and has adverse effects on the live weight of the pigs.


Introduction
pork are still forced to deliver pigs with higher meat content of carcass (Cisneros et al., 1996).
Rearing the pigs at geographically separated Lean meat per cent of pig carcass depends on areas from slaughter plants is an important issue animals' slaughter live weight.Beattie et al ., from sanitary points.Large numbers of pigs, (1999) emphasized increasing slaughter weight therefore, have to be transported to centralized resulted reducing costs per unit weight, slaughter houses at the end of the production increasing carcass yields, and improving meat to period.Since, pre-slaughter procedures such as handling to remove from farm, loading and bone ratio.unloading during transportation could be The stress factors during the transportation traumatic and stressful for pigs; the maximum of pigs could be divided into two main groups as care should be taken during that process.physical and mental (Vecerek et al., 2006 reported as existence of feed and drinking water, From the point of view of nutrition and anxiety and fear.All these factors increase the secretion of some hormones and enzymes under the pressure of consumers, producers of resulting remarkable raise at concentration of regression between live and dress weight using these metabolites in blood and this process affects the SPSS 10.0 software.Regression equations for the meat quality adversely.
live weight and dress weight data in the The adverse effects of the trips on pigs are transportation period and sex were fitted to the strongly correlated with length and duration of following regression model: linear function of trip and this is directly related with the distance DW = B + ß LW.If the linear was non 0 1 between production house and slaughter plant.significant, then quadratic function was fit.This study aims to investigate the possible effects Statistical analysis: All data were expresses as a of different transportation period, sex on live percentage of live weight.Effect of live weight, weight and dress weight of pigs.Thus to develop dressed carcass weight on transport distance and regression formula between live weight and dress sex effect was determined using 77 replicates.weight of pigs that could be used to predict dress Completely randomized design model of the weight as affected by transportation period and sex.experiment was used and Duncan test was

Materials and Methods
applied to determine the differences among treatments.Further data was then analyzed by The study was carried out in Keells Food regression between live and dress weight using Products abattoir in Ekala, Ja-ela Sri Lanka the SPSS 10.0 software.Regression equations for during January to February 2011.539 Land Race live weight and dress weight data in the different × Large White cross bred samples were randomly transport distance and sex categories were fitted selected according to transport distance away to the following regression model: linear function from the Keells Food Products abattoir (<4 Km, of dress weight = B + ß live weight.If the linear 0 1 10 Km, 12 Km, 22 Km, 30 Km, 55 Km, 90 Km) was non significant, then quadratic function was fit.and different sex category (bacon castrated, gilt, bacon boar) to determine the impact of the Results and Discussion transport distance and sex effect on carcass As live weight at slaughter increased there characteristic of pig.The pigs were slaughtered at were significant increases in carcass weight 28 week of age (corresponding to a carcass (p<0.001) and dressing percentage (p<0.05).weight of approximately 90 kg).The deliveries Carcass weight is highly correlated with live were carried out under similar conditions and weight (r= .93,p = 0.00).And also, carcass similar loading density (20 animals per vehicle).
weights is increased linearly (P < .001)with All pigs from each group were processed at the slaughter live weight (Figure 1).Furthermore, same time.They were weighed immediately Correa et al., (2006) found as live weight before and after transport.Corresponding weight increased there were significant increases could losses during transport were calculated and be observed in hot carcass weight and dressing expressed as a percentage of initial live weight.percentage (P < 0.05).There were significant Then the all pigs were slaughtered after 24 h rest effect of sex on live weight at slaughter, carcass in bedded lairage space, with full access to food weights and dressing percentage (p<0.01).This and water.Each pigs were weighed at slaughter, increase in carcass yield is consistent with Gu et subjected to stunning, allowed for bleeding,   Greater slaughter weight has the advantage weight loss upon leaving the farm until they reach of reducing the overhead costs for producers, slaughter.Transport losses cause direct financial slaughterers and processors by increasing carcass losses to pig producers and pork processors.As yields, improving meat to bone ratio and reducing shown in Table-1, the longer the transport chilling and processing losses (Ellis and Bertol, distance the percentage of pigs weight lost was 2001).Slaughter weights for hog in the Sri Lanka higher (P<0.01).Main lost was found for 90 Km have been increasing steadily over recent years distance (compare with other distances) of bacon and currently average approximately 95 kg for boar was recorded as 31.37 %, which was slaughter barrows and gilts.The potential considerably higher than the other transport advantages of producing heavier pigs are widely distances (<0.01).
recognized by the slaughtering industry, and this sector would like to increase slaughter weights above current levels.Furthermore, at heavier weights, pork quality was rated higher in terms of juiciness, flavour and tenderness (Piao et al., 2004) and would be attributable to differences in intramuscular fat composition (Hugo et al., 1999).
Transport to the slaughterhouse is a considerable stress burden for pigs.The stress burden level of pigs is especially influenced by the method of treatment of animals at the point of loading, during transport, at the unloading of animals from the transport, transport distance and transportation time.The stress burden of the pigs also increases with the increasing transport distance or transportation time to the slaughter house.Perremans and Geers (1996) emphasise Warris et al., (1990) compared the effect of the impact of transportation time on the stress pre-slaughter transport time on carcass and meat burden of pigs.quality and showed that longer transport time of The mean dressing percentages from transport pigs increased live weight loss while resulted in period are presented in

0Figure- 1
Figure-1 Relationship of Live Weight and Carcass Weight of pigs ; Mota-According to literature pigs where transported for Rojas et al., 2006; Becerril-Herrera et al., 2007).long distance to the slaughter houses resulting The physical factors were titled as temperature, remarkable production loss (Warriss et al., 1983; wind, air flow, gas content and oscillation of Bradshaw et al., 1996; Kim, 2004; Lambooy and vehicle used in transit, whilst mental factors were Engel, 1991).

Table - 1: Body weight loss (%) of different sex category of pig at different transport period there
were significant increases in dressing yield to be lower than bacon boar for both factors Table as live weight at slaughter increased (P < 0.05).1.Moreover, they showed greater carcass weight The weight loss of pigs in different transport loss during 24 h cooling (35.65% vs. 26.75% ; P distances of bacon castrated, gilt, bacon boar ?0.01).This emphasizes the profound effect of during transportation to abattoir were given in long-distance transport on final carcass properties.Table 1 (p<0.05).Pigs generally experience a live

Table -
Cisneros, F., Ellis, F. K. M., McKeith, J. M., It is therefore, suggested that the distance and Fernando.R.,(1996)Influence of between production house and slaughter plant slaughter weight on growth and carcass should not exceed 55 km.According to this the characteristics, commercial cutting and decrease of slaughter weight by each 10 kg leads curing yields, and meat quality of barrows to increase in lean meat per cent of pig carcass by and gilts from two genotypes.J. Anim.Sci.1.5 per cent points.As a conclusion, transportation 74:925-933. of the pigs is a stress factor and has adverse 5. Correa J.A., Faucitano L., Laforest J.P., effects on the live weight of the animals Rivest J., Marcoux M., and Gariepy C., remarkably.The effects of the transportation have (2006) Effects of slaughter weight on a linear relationship with the body weight of the carcass composition and meat quality in pigs and extensions of transportation distance pigs of two different growth rates Meat have severe adverse effects on live weight.Science,72, 1, 91-99.Differences between means are important in the same row shown by different letters (p<0.05) *