Factors affecting the mortality of pigs being transported to slaughter

A multilevel logistic regression model was used to identify and quantify the effects of factors affecting the mortality of pigs being transported to slaughter under commercial conditions. A survey of 739 journeys to 37 slaughterhouses in five eu countries was carried out, and information potentially related to the welfare and mortality of the pigs and the number of injuries were recorded. The average temperature during the journey, its duration, the average loading time per pig, the recorded injuries, fasting before transport, and the interaction between fasting and journey duration were used in the final model. The average mortality was 0.11 per cent and the average proportion of injured pigs was 0.36 per cent, and these figures were significantly correlated (P<0.001). In 29 per cent of the journeys the pigs were not fasted before being loaded, which doubled the risk of mortality irrespective of whether the pigs were injured or not. The risk of mortality increased with average temperature. In journeys with fasted pigs that did not have any recorded injury, average temperature was more important than the duration of the journey. The risk of mortality increased as the average time taken to load them decreased, and the risk was highest when the pigs were not fasted and when injuries were recorded. Other factors such as the country, loading density, availability of drinking water and type of ventilation did not affect the risk of mortality.     

Comparison of serologic testing and slaughter evaluation for assessing the effects of subclinical infection on growth in pigs

OBJECTIVE: To compare serologic testing with slaughter evaluation in assessing effects of subclinical infection on average daily weight gain (ADG) in pigs. DESIGN: Cohort study. ANIMALS: 18 cohorts (30 to 35 pigs/cohort) of pigs on/farms. PROCEDURE: Blood samples were collected, and pigs were weighed at 8, 16, and 24 weeks of age. Sera were tested for antibodies to porcine reproductive and respiratory syndrome virus (PRRSV), swine influenza virus (SIV), transmissible gastroenteritis virus (TGEV), pseudorabies virus, Mycoplasma hyopneumoniae, and Actinobacillus pleuropneumoniae. At slaughter, skin, nasal turbinates, lungs, and liver were examined. Associations between ADG and results of serologic testing and slaughter evaluation were examined by use of multiple linear regression. RESULTS: Pathogens that had a significant effect on any given farm during any given year and the magnitude of that effect varied. However, at 16 and 24 weeks of age, a higher antibody titer was consistently associated with a lower ADG. Mean differences in ADG between seropositive and seronegative pigs were 18 g/d (0.04 lb/d) for SIV, 40 g/d (0.09 lb/d) for PRRSV, 38 g/d (0.08 lb/d) for M hyopneumoniae, and 116 g/d (0.26 lb/d) for TGEV. Of the evaluations performed at slaughter, only detection of lung lesions was consistently associated with a decrease in ADG. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that subclinical infection with any of a variety of pathogens commonly found in swine herds was associated with a decrease in ADG. Serologic testing was more effective than slaughter evaluation in assessing the impact of subclinical infection on ADG in these pigs.     

Effects of journey and lairage time on steers transported to slaughter in Chile

Steers representative of the most common type, weight and conformation slaughtered in Chile were transported for either three or 16 hours and held in lairage for three, six, 12 or 24 hours. Measurements of liveweight, carcase weight, and the postmortem pH and colour of muscle were made to assess the economic and welfare effects of the different transport and lairage times. Compared with the short journey, the longer journey was associated with a mean (se) reduction in liveweight of 8.5 (2.8) kg, and there was a further decrease of 0.42 (0.18) kg for every hour that the animals were kept in lairage after 16 hours of transport, an increase in final muscle pH, a decrease in muscle luminosity and an increase in the proportion of carcases downgraded because they were classified as 'dark cutting The carcase weights also tended to be lower after the longer journey and after longer periods in lairage.     

Behavioural and physiological responses of pigs to being transported for up to 24 hours followed by six hours recovery in lairage

Ninety-six pure-bred Large White pigs weighing 80 to 100 kg were either not transported or transported for eight, 16 or 24 hours, and then either slaughtered immediately on arrival at the abattoir or kept in lairage for six hours before being slaughtered. The pigs travelling for eight, 16 or 24 hours lost 2.2, 2.0 and 4.3 per cent of liveweight, respectively, and the pigs travelling for 24 hours lost 2.6 per cent of hot carcase weight Both liveweight and hot carcase weight recovered during the lairage period although there was a net liveweight loss in comparison with the control animals. Only transport for 24 hours led to losses in carcase weight The concentration of non-esterified fatty acids increased with the time spent travelling. The concentrations of cortisol, creatine phosphokinase and lactate were all low in comparison with the levels found in commercially slaughtered animals. Plasma albumin and protein concentrations indicated that the animals were becoming dehydrated during the longer journeys. The animals lay down for most of the journey and appeared to be asleep. During the period in lairage, the animals transported for eight hours had two distinct periods of feeding and drinking but spent most of the time lying down, but those transported for 16 and 24 hours showed far more eating and drinking activity. All the groups appeared tired, but the urge to eat of the groups transported for 16 hours, and especially 24 hours appeared to be more important. There were behavioural and the physiological differences between the transported groups and the controls. Six hours in lairage with access to food and water allowed most of the physiological parameters to return to pretransport levels.     

Behavior,blood stress indicators,skin lesions,and meat quality in pigs transported to slaughter at different loading densities

A total of 1,936 pigs were transported through 8 trips (8.4 ± 0.5 hr) from 2 grow-to-finish farms to a commercial slaughter plant, all located in Southern Brazil. On each trip, a sub-sample of each load (36 barrows/load, weighing 118.9 ± 9.8 kg) was randomly allocated into one of the following loading densities during transport: 200 kg/m² (D200), 235 kg/m² (D235), and 270 kg/m² (D270). Behavioral recordings of postures and activities were made during transportation and lairage using video-cameras. At slaughter, blood samples were collected to assess the concentrations of creatine kinase (CK) and lactate. Carcass weights and skin lesion scores were assessed on-line, and meat quality was evaluated in the longissimus thoracis (LT) muscle by assessing pH, color, and drip loss. During transportation, the proportion of animals lying down was higher (P < 0.05) in D200 and D235 groups compared with D270. The proportion of sitting animals during transportation was higher (P < 0.01) in D270 compared with D200. In lairage, D200 and D235 pigs stood more compared with D270 (P = 0.01), while the proportion of lying pigs was higher (P = 0.02) for D270 pigs compared with D200 and D235. The frequency of drinking bouts in lairage was higher (P < 0.05) for D200 group compared with D235 and D270. The levels of CK were lower (P < 0.05) in D200 pigs transported compared with D270. Lesion scores tended to be higher (P = 0.06) in D270 carcasses compared with D200 and D235. A tendency for lower (P = 0.10) pH1 values in the LT muscle of D270 pigs compared with D200 pigs was also found. Based on the results of this study, the application of lower loading densities (≤235 kg/m²) in the truck allows pigs to have sufficient space to rest, travel more comfortably and arrive less fatigued at the slaughter plant.     

Patterns and durations of journeys by horses transported from the USA to Canada for slaughter

Concern has been expressed over the welfare of horses transported from the USA for slaughter in Canada. United States Department of Agriculture owner/shipper certificates for the year 2009 were analyzed to provide quantitative information on the patterns and durations of these journeys. In 2009, horses from 16 states in the northern USA were transported to 6 equine slaughter plants in Canada. Thirty-two percent of loads were from auction centers, 33% from feedlots, and 35% from horse collection centers. The median duration of the journey was 19 h. Thirty-six percent of horses were transported for < 6 h, 11% for 6 to 18 h, 13% for 18 to 24 h, 25% for 24 to 36 h, 9% for 36 to 48 h, and apparently 6% > 48 h. Some journeys exceeded those specified in regulations and, based on other research, would put these horses at risk of negative welfare outcomes, such as dehydration, injury, and fatigue.     

Evaluation of the effects of enzootic pneumonia in pigs on weight gain and days to slaughter under New Zealand conditions

The effects of enzootic pneumonia on average daily weight gain and number of days taken to reach slaughter weight was studied in 333 bacon-weight pigs. Each 1% of lung volume affected by enzootic pneumonia was shown to reduce average daily gain by 2.2 grams and increase the numbers of days to slaughter by 0.61 days. The cost of these reductions in performance was calculated to be about NZD 1 for each 1% of lung affected.     

Effects of trailer design on animal welfare parameters and carcass and meat quality of three Pietrain crosses being transported over a short distance

The objective of this study was to evaluate the effects of trailer design on the stress responses and meat quality traits of 3 different pig crosses: 50% Pietrain breeding with HAL^Nn (50Nn), 50% Pietrain breeding with HAL^NN (50NN) and 25% Pietrain breeding with HAL^NN genotype (25NN). Market barrows (n=360), as a subset of 12 trailer loads of pigs, were transported from farm to slaughter on 6 dates in 2009 for 45 min in either a pot-belly (PB) or flat-deck (FD) trailer, with 120 pigs/genetic group being represented. Temperature (T) and relative humidity (RH) were recorded by data loggers mounted in both trailers. Behaviours and handler interventions were video-taped at loading, unloading and in lairage. At exsanguination, blood samples were collected for the assessment of lactate, cortisol, creatine kinase (CK), haptoglobin and Pig-MAP concentrations. Meat quality was measured in the longissimus dorsi (LD), semimembranosus (SM) and adductor (AD) muscles of all pigs. Temperatures were warmer in compartments 6 and 11 at loading (P<0.001), compartment 11 during travelling (P=0.05), and in compartment 5 at unloading (P=0.01) of the PB trailer. Pigs unloaded from the FD trailer overlapped more (P<0.001), whereas (P<0.001) the frequency of jamming was noted for pigs unloaded from the PB trailer. Pigs with 50% Pietrain genetics overlapped and jammed more (P<0.001) than pigs with 25% Pietrain genetics, regardless of HAL status. Greater (P=0.03) CK levels were found in 50Nn pigs transported in the PB trailer, while 50Nn and 50NN pigs had greater (P=0.028) lactate levels than 25NN pigs. Carcasses from 50Nn and 50NN pigs were leaner (P=0.04), and the skin damage score was lower (P=0.04) in 25NN carcasses. Overlap-type bruises were greater (P=0.02) in pigs transported in the FD trailer. Pigs transported in the PB trailer had greater (P=0.05) pHu in the SM and AD muscles (P=0.013). Except for pHu in the SM muscle, all meat quality parameters were affected by the Hal gene (P=0.04). The use of a PB trailer for short distance transportation of pigs to slaughter negatively affected stress responses and meat quality. The greater proportion of Pietrain genetics in the selection resulted in leaner carcasses, but also in pigs being more difficult to handle. Crossbreeding appeared to have a greater impact on animal welfare and meat quality than vehicle type, but trailer type may emphasize these negative genotype-related defects.     

Effects of trailer design on animal welfare parameters and carcass and meat quality of three Pietrain crosses being transported over a long distance

This study aimed at evaluating the effects of trailer design on stress responses and meat quality traits of 3 different pig crosses: 50% Pietrain breeding with halothane (HAL)(Nn) (50Nn); 50% Pietrain breeding with HAL(NN) (50NN); and 25% Pietrain breeding with HAL(NN) genotype (25NN). Over a 6-wk period, pigs (120 pigs/crossbreed) were transported for 7 h in either a pot-belly (PB) or flat-deck (FD) trailer (10 pigs/crossbreed(-1.)trailer(-1.)wk(-1)). Temperature (T) and relative humidity (RH) were monitored in each trailer. Behaviors during loading and unloading, time to load and unload, and latency to rest in lairage were recorded, whereas a sub-population of pigs (4 pigs/crossbreed(-1.)trailer(-1.)wk(-1)) was equipped with gastro-intestinal tract (GIT) temperature monitors. Blood samples were collected at exsanguination for measurement of cortisol, creatine kinase (CK), lactate, haptoglobin, and Pig-MAP concentrations. Meat quality data were collected at 24 h postmortem from the LM and semimembranosus (SM) and adductor (AD) muscles of all 360 pigs. Greater T were recorded in the PB trailer during transportation (P = 0.006) and unloading (P < 0.001). Delta GIT temperature was greater (P = 0.01) in pigs unloaded from the PB. At loading, pigs tended to move backwards more (P = 0.06) when loaded on the FD than the PB trailer. At unloading, an interaction was found between trailer type and crossbreed type, with a greater (P < 0.01) frequency of overlaps in 50NN and 25NN pigs and slips/falls in 50Nn and 50NN pigs from the FD than the PB trailer. Cortisol concentrations at slaughter were greater (P = 0.02) in pigs transported in the PB than FD trailer. Greater lactate concentrations were found in 50Nn and 50NN pigs (P = 0.003) and greater CK concentrations (P < 0.001) in 50Nn pigs. As expected, 50Nn pigs produced leaner (P < 0.001) carcasses, with greater (P = 0.01) dressing percentages, as well as lower (P < 0.001) ultimate pH values and greater (P < 0.001) drip loss percentages in the LM and greater (P = 0.002) drip losses and a paler color (greater L* values, P = 0.02) in the SM than 50NN pigs. When used for long distance transportation under controlled conditions, the PB trailer produced no detrimental effects on animal welfare or pork quality. Pigs with 50% Pietrain crossbreeding appear to be more responsive to transport stress, having the potential to produce acceptable carcass and pork quality, provided pigs are free of the HAL gene.     

CO2-stunning of slaughter pigs: effects on EEG, catecholamines and clinical reflexes

Investigations were carried out on the response of slaughter pigs to CO2 stunning with two different gas concentrations (80 vol%, 90 vol%, 73 s) under practical conditions in a one gondola-dip-lift system. EEG measurements were performed and blood constituents such as catecholamines (adrenaline, nor-adrenaline) and lactate as well as clinical reactions (nasal septum and corneal reflex, heart beats) investigated. Special EEG-electrodes were adapted for the measurement on pigs and a mobile data logger was prepared for the use in the lairage of the slaughter house and in the stunning unit. The CO2 concentrations were measured continuously close to the head of the pigs when transported up and down in the stunning gondola. The results show that the technique is suited to monitor the effects of different CO2 gas concentrations on the EEG of the pigs under practical conditions. There is strong evidence that CO2 concentrations of 80 vol% applied over 70 s as required by law are not sufficient to stun pigs properly. A large part of the animals still showed typical reflexes when leaving the stunning pit. When an atmosphere of 90 vol% CO2 is applied, most animals are already dead before bleeding commences. This may create problems in respect to meat hygiene. The blood analysis revealed very high concentrations of catecholamines after stunning. The values for adrenaline and nor-adrenaline in the sticking blood rose by a factor of about 1000 as compared to the concentrations in blood samples taken in the lairage before stunning. It seems necessary to revise the current legislation on gas stunning and to look in greater detail in the effects of CO2 stunning on the welfare of slaughter pigs.     

Effect of removal and remixing of lightweight pigs on performance to slaughter weights

Two experiments were conducted to determine the effect of lightweight pig removal and remixing on performance to slaughter. Experiment 1 was a growing-finishing trial utilizing a total of 900 pigs (26.2+/-0.1 kg initial weight) that were sorted and remixed at a mean replicate BW of 72 kg. Experiment 2 was a wean-to-finish trial (17 d mean wean age; 4.8 kg +/- 0.1 BW) utilizing 225 barrows with sorting and remixing occurring 3 wk after weaning. Treatments were 15 pigs/ pen from initial weight to slaughter (15S), 20 pigs/pen from initial weight to time of sort and remix and then reduced to 15 pigs/pen (20/15), and 15 pigs/pen from time of sort and remix to slaughter comprised of the five lightest pigs from each of three 20/15 pens per replicate (15M). Space allocation was 0.56 m2/pig from 26 to 70 kg and 0.74 m2/pig thereafter in Exp. 1. In Exp. 2, pen size was fixed at 2.44 x 4.27 m. In Exp. 1, there was no effect (P > 0.20) of treatment on performance prior to 70 kg. Least squares means for ADG from time of sort and remix to first pig removal from a pen for slaughter at 113 kg were 0.93, 0.87, and 0.91 kg/d for the 20/15, 15M, and 15S treatments, respectively (P < 0.05). When comparing the population represented by the 20/15 + 15M treatments vs the 15S population, there was no difference (P > 0.20) in ADG, ADFI, feed conversion, or carcass lean content. In Exp. 2, pigs in the 20/15 treatment grew slower (P < 0.05) than 15S pigs for the first 21 d (0.20 vs 0.22 kg/d, respectively) with a lower ADFI (P = 0.06) and no difference in feed conversion. When comparing the population represented by the 20/15 + 15M treatments vs the 15S population after sorting and remixing, there was no effect (P > 0.15) of experimental treatments on ADG, ADFI, feed conversion efficiency, carcass lean content, or daily lean gain. These results suggest that removal of lightweight pigs and remixing of the removed pigs into pens of similar-weight pigs is ineffective in improving the overall performance of a population of pigs during the postweaning period.     

人道屠宰对猪肉品质的影响

<正>人道屠宰广义上讲就是在动物的运输、装卸、停留待宰以及宰杀过程中,采取合乎动物行为的方式,以尽量减少动物的紧张和恐惧,也就是要善待动物,     

Residues of azaperone and azaperol in slaughter pigs

An investigation was carried out to determine the residues of azaperone in slaughter pigs and pig meat products. The butyrophenone tranquillizer azaperone is frequently administered to pigs by intramuscular injection in order to reduce mortality and loss of meat quality resulting from transportation from the farm to the slaughter house. In the pig, following administration of azaperone as recommended by the manufacturer (0.4 mg/kg i.m.) residue concentrations of about 0.05 μg/g azaperone, and 0.20 μg/g azaperol (the main biotransformation product in the pig) were found in the kidneys; the kidneys proving to be the sampling organs of choice. Pasteurization and other technological procedures did not influence residues measurably. Toxicological evaluation suggests that the residues found do not per se constitute a danger to public health. None the less, the presence of any drug residue in meat or meat products is undesirable, and alternative, non-pharmacological approaches to the problems arising from transportation prior to slaughter should be considered.     

Questionnaire assessment of the welfare of pigs

A questionnaire study was performed involving 76 farms with a total of 380,207 pigs to assess the welfare of pigs kept in Hungary based on the animal welfare legislation of the European Union. Most significant deficiencies were found in the fulfillment of the provisions relating to space requirements, the stall microclimate and the behavioural needs of the animals.     

Influence of crate height during slaughter transport on the welfare of male turkeys

1. Poultry are usually transported in crates which provide the birds with very limited space. Slaughter transport of male turkeys is often carried out using crates that are 40?cm or less in height where it is not possible for them to stand up. There is little information on how this physical restriction over many hours affects the birds.

2. The aim of the study was to compare the welfare of male turkeys transported in crates 40?cm and 55?cm in height. Observations on the birds’ behaviour during lairage, carcass damage and meat quality were carried out after four commercial slaughter transport journeys.

3. Birds in 40?cm crates panted more and lay down more than birds in 55?cm crates during lairage. A large percentage of the carcasses had some damage. Significantly more birds from the 55?cm crates had scratches on their backs than birds from the 40?cm crates. There was no significant difference in meat quality between birds transported in the two crate heights.

4. Both positive and negative effects of increased crate height were established and there is no evidence from this study that merely increasing crate height improves turkey welfare. Other solutions should therefore be sought in order to improve the welfare of birds during transport.     

Insensibility during slaughter of pigs in comparison to other domestic stock

The onset of insensibility during slaughter was studied in five, 31-day-old pigs. The state of sensibility was determined from the study of electroencephalograms (EEC) which were of a bipolar transhemispheric derivation. In 3 pigs slaughtered by bilateral severance of both common carotid arteries and jugular veins, it was judged that insensibility occurred within 25s and there was no resurgence of cerebrocortical activity following subsequent respiratory gasps. The EEGs became isoelectric within 115s. These results are compared with previous findings by the authors that adult sheep and lambs slaughtered by similar techniques became insensible within 7s whereas, in calves, the onset of insensibility was delayed for up to 85s and there were resurgences of cerebrocortical activity, following a respiratory gasp, for more than 300s.

These differences in the apparent onset of insensibility in the 3 species of animal are discussed in relation to the anatomical features and possible dynamics of the blood supply to the brain during slaughter.

It is concluded that for humane reasons, “head-to-back” electrical stunning of pigs is preferable to a “head-only” method.     

Insensibility during slaughter of pigs in comparison to other domestic stock

The onset of insensibility during slaughter was studied in five, 31-day-old pigs. The state of sensibility was determined from the study of electroencephalograms (EEC) which were of a bipolar transhemispheric derivation. In 3 pigs slaughtered by bilateral severance of both common carotid arteries and jugular veins, it was judged that insensibility occurred within 25 s and there was no resurgence of cerebrocortical activity following subsequent respiratory gasps. The EEGs became isoelectric within 115 s. These results are compared with previous findings by the authors that adult sheep and lambs slaughtered by similar techniques became insensible within 7 s whereas, in calves, the onset of insensibility was delayed for up to 85 s and there were resurgences of cerebrocortical activity, following a respiratory gasp, for more than 300 s. These differences in the apparent onset of insensibility in the 3 species of animal are discussed in relation to the anatomical features and possible dynamics of the blood supply to the brain during slaughter. It is concluded that for humane reasons, head-to-back electrical stunning of pigs is preferable to a head-only method.     

Effect of feed withdrawal prior to slaughter on prevalence of gastric ulcers in pigs

OBJECTIVE: To determine whether withdrawing feed from pigs prior to slaughter had any effects on prevalence or severity of gastric ulcers. DESIGN: Split-plot design. ANIMALS: 873 pigs. PROCEDURES: At the finishing barn, pigs were assigned to 30 pens. Feed withdrawal times (0, 12, or 24 hours) were assigned to pens at random, and pigs in each pen were marketed in 3 groups over a period of 4 weeks. The first marketing group consisted of the 10 heaviest pigs in each pen, the second consisted of the next 10 heaviest, and the third consisted of all remaining pigs. Feed was withheld from all pigs in each pen prior to removal of each marketing group. Thus, feed was withheld once, twice, or 3 times for pigs in the first, second, and third marketing groups, respectively. RESULTS: Feed withdrawal time was not significantly associated with ulcer score at the time of slaughter. Ulcer scores and prevalence of chronic damage were higher in the third marketing group, regardless of feed withdrawal time. Prevalence of severe damage, prevalence of chronic damage, and prevalence of esophageal constriction increased as carcass weight decreased. No pigs died of gastric ulceration. CONCLUSION AND CLINICAL RELEVANCE: Results suggest that withdrawal of feed from pigs prior to slaughter does not increase damage to the stomach and that repeated feed withdrawal does not result in fatal gastric ulceration.     

Effect of organic acids in drinking water during the last 2 weeks prior to slaughter on Salmonella shedding by slaughter pigs and contamination of carcasses

In this study, we investigated the effect of adding organic acids to the drinking water of finishing pigs 2 weeks prior to slaughter on the shedding and prevalence rate of Salmonella at slaughter. Approximately 600 animals from four Belgian pig herds infected with Salmonella were included. At two herds, the study was conducted twice. Before the start of the study, overshoes were taken at the different herds. Two weeks prior to the expected slaughter date, the pigs were randomly divided into two groups (treatment and control group) each containing on average 50 animals within each herd. The treatment group received from this day onwards acidified drinking water (pH = 3.6-4.0), the control group received non-treated water (pH = 7.8-8.5). All other housing, feeding and management factors were identical in both groups. At the slaughterhouse, 10 pigs of each group (20 pigs for each group of study group 6) were randomly selected and sampled (blood, contents of ileum and rectum, mesenteric lymph nodes and carcass swabs). All samples were immediately transported to the laboratory and submitted to Salmonella isolation. Salmonella was isolated out of 11.9% (66/554) of the samples taken at the slaughterhouse, with the highest frequency found in the content of the ileum (18.7%), followed by 17.8% in the lymph nodes, 7.2% in the content of the rectum and 3.6% in the carcass swabs. The results did not reveal a significant difference between the treatment and control groups for the different slaughterhouse samples. The study documented that the investigated control strategy namely, the strategic application of organic acids during the last 2 weeks prior to slaughter was insufficient to decrease Salmonella shedding and contamination shortly before and during slaughter.