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Groups of pigs were subjected to three different systems of loading and unloading to and from commercial animal transporters. The systems under trial were: the use of a hydraulic tail-lift, a tail board ramp at an angle of 18° and a modular system. The module was a container 2 m x 2.4 m x 1 m high into which the pigs were loaded. The module could then be lifted on and off the lorry with a fork lift truck. Non-invasive monitoring techniques were used to study the responses of the pigs. A subjective handling score, time taken to load and unload, skin temperature, heart rate and salivary cortisol were recorded. Loading and unloading were subjectively assessed as being easiest and quickest using the modular system, which also appeared to be less physically demanding for the animals, as evidenced by lower heart rate and a reduced maximum heart rate. However, with the modular system, elevated cortisol was found during the loading, unloading and resting periods. This could be interpreted as indicating that the pigs were unable to settle in the module and suffered some small degree of stress, which might become more of a problem during prolonged transport. Of the other two systems, there appeared to be little difference between the hydraulic tail-lift and the ramp. [ABSTRACT FROM AUTHOR]

1. Standardised data on husbandry were recorded for a flock of birds in one house on each of 150 broiler farms in the UK during the 4 d prior to slaughter. 2. For each flock, the incidence of birds found dead on arrival (DoAs) and the Meat Hygiene Service carcase rejection records were recorded at the slaughterhouse. 3. The mean percentage of birds in each flock found DoA was 0.12% (range 0-0.64%) and the mean percentage of Total Carcase Rejects (TCRs) for each flock was 1.23% (range 0.07-5.51%). 4. A general linear model was developed to examine factors associated with flock percentage DoAs. Assuming a linear relationship, all other factors remaining the same, a one percentage point (PP) increase in small/emaciated birds will result in a 0.155 PP increase in DoAs and a 1 PP increase in wheat in diet 4 will result in a 0.003 PP decrease. An increase by one in the total number of vaccines administered will cause a 0.029 PP decrease in DoAs, a 1 g increase in live weight at slaughter will be associated with a 0.000043 PP increase and a 1 PP increase in mortality on farm would be associated with a 0.000044 PP increase. A 1 PP increase in Ross birds decreases DoAs by 0.0004 PPS: there is also a seasonal effect. 5. The model developed for flock percentage TCRs found that a 1 PP increase in wheat in diet 3 will result in a 0.052 PP decrease in TCRs and a 1 PP increase in Ross birds will cause a 0.009 PP decrease. A 1 PP increase in birds culled on farm will be associated with a 0.03 PP increase in TCRs and the diagnosis of disease during the flock cycle increases TCRs by 0.397 PPs. A one day increase in age at slaughter will result in a 0.046 PP increase in TCRs.

1. The effects of rearing chickens using standard, maize-fed, free-range or organic production systems on meat quality and sensory characteristics were evaluated. The standard system used either Ross or Cobb birds with a slaughter age of approximately 40 d, the other systems in the trial used Hubbard birds with considerably older slaughter ages, up to 72 d in the case of organic systems. 2. Paired breast fillets from 120 birds, 30 from each rearing system, were used. The meat quality variables, ultimate pH, colour coordinates L*, a*, b* and water-holding capacity were measured and taste panel assessments were made using 8-point category scales of texture, juiciness, abnormal flavour, flavour liking and overall flavour. 3. There were significant differences between rearing systems, with fillet muscles from birds grown under the standard system having a higher ultimate pH. Differences were also seen in colour with fillets from birds reared under a standard system having a smaller hue angle than those grown using the maize-fed system which had the highest. 4. Fillets from birds reared in the standard system were rated by the taste panel as more tender and juicy. There were no significant differences in chicken flavour. Based on hedonic assessments of flavour liking and overall liking, by a small panel of assessors, meat from birds produced in the standard system was most preferred and that from organic systems the least preferred. Meat from free-range and maize-fed systems was intermediate in preference. This result reveals a trend, but does not infer consumer acceptance.

1. Standardised data on flock husbandry were recorded on 149 broiler farms during the 4 d prior to slaughter. 2. Birds were examined at the slaughterhouse for contact dermatitis lesions. Foot pad dermatitis score (FPDS) and hock burn score (HBS) were measured on five point scales. Carcase rejection data were also collected. 3. The mean percentage of birds in each flock with: moderate or severe foot lesions was 11.1% (range 0-71.5%); moderate or severe hock burn was 1.3% (range 0-33.3%); and, breast burn was 0.02%. 4. A general linear model was developed to examine factors associated with mean flock FPDS. Assuming a linear relationship, within the range of data collected and with all other factors remaining the same, every 1% increase in the proportion of Genotype A birds in the flock was associated with an increase in mean FPDS of 0.003, every one-point increase in litter score was associated with a 0.326 increase in mean FPDS and every one-point increase in flock mean HBS was associated with a 0.411 increase in mean FPDS. Flock mean FPDS was associated with feed supplier and was higher in winter. 5. The general linear model developed for flock mean HBS, found that every one-point increase in mean FPDS increased mean HBS by 0.090, every one-point increase in litter score increased HBS by 0.119 and, every 1% increase in small/emaciated birds decreased mean HBS by 0.333. Reduced HBS was also associated with increased final litter depth, younger slaughter age and an increased percentage of dietary wheat. For every 1% increase in Genotype A birds, a decrease in flock mean HBS of 0.003 would be expected. 6. An effect of hatchery was also identified.

1. The prevalence and severity of foot pad dermatitis (FPD) was examined in 359 flocks of broiler chickens comprising about 3.93 million birds produced on 91 farms and reared under 5 types of system: standard intensive, free-range, organic, systems complying with the RSPCA Freedom Food scheme, and corn-fed. 2. The mean prevalence of FPD in standard systems was 14.8%. Flocks that had access to the outside (free-range and organic systems) showed higher prevalence of FPD than those kept entirely indoors (standard, corn-fed and Freedom Food systems). The lowest prevalence of FPD (9.6%) and severity of the lesions occurred in Freedom Food systems, and the highest prevalence (98.1%) and severity in organic systems. 3. The implication from the results is that there are large variations in the prevalence and severity of FPD in birds reared under different systems and this needs to be taken into account when assessing the overall welfare associated with each type of system.

The relation between measurements of colour made in the m. adductor (AD) at 45min or 20 h post mortem and the quality, assessed subjectively in terms of colour and waterholding capacity, of the m. longissimus (LD) in the loin was examined. The study used data from 100 pig carcasses exhibiting a wide range of meat quality from extreme PSE (pale, soft and exudative) to extreme DFD (dark, firm and dry). The subjective assessments were confirmed by objective measures of paleness (reflectance) and waterholding capacity (drip loss in storage) in the LD. Lightness (L(∗)) measured at 20h post mortem in the AD was the best potential predictor of loin muscle quality, explaining 59% of the variation in subjective and objective quality measures. Comparable measurements at 45min post mortem explained between 21% and 44% of the variation. The equation that described the relation between AD Lightness (L(∗)) and subjectively assessed LD quality was derived. This could be used to transpose the AD L(∗) values from a population of slaughtered pigs into nominal subjective scores for the LD, allowing the frequency of the five subjective quality groups (extremely DFD, slightly DFD, normal, slightly PSE, and extremely PSE) in the population of carcasses to be defined.

Management practices, stocking rate and flock size may affect laying hen welfare but there have been few replicated studies in commercial non-cage systems that investigate this. This study used a broad range of physical and physiological indicators to assess the welfare of hens in 36 commercial flocks. Six laying period treatments were examined with each treatment replicated 6 times. It was not possible to randomly allocate treatments to houses, so treatment and house were largely confounded. Three stocking rates were compared: 7 birds/m(2) (n = 2450), 9 birds/m(2) (n = 3150) and 12 birds/m(2) in either small (n = 2450) or large (n = 4200) flocks. In addition, at 12 birds/m(2), in both small and large flocks, birds were subjected to either standard (SM) or modified (MM) management. MM flocks had nipple drinkers and no nest-box lights. Bone strength, fracture incidence, heterophil:lymphocyte (H:L) ratio, live weight, organ weights, serum creatine, serum osmolality, muscle pH and faecal corticosterone were measured on samples of birds at the end of the rearing period and at the end of lay. During the laying period, mortality, production and integument condition were recorded at regular intervals. Birds housed at 9 birds/m(2) had higher mortality than birds housed at 12 birds/m(2) by the end of lay, but not higher than birds housed at 7 birds/m(2). Birds housed at 7 and 9 birds/m(2) had lower percent liver weight, and worse plumage condition than most of the 12 bird/m(2) treatments. Modified management tended to improve plumage condition. There were no clear effects of flock size on the welfare indicators recorded. At the end of the rearing period fracture incidence was almost negligible and H:L ratio was within a normal range. By the end of lay fracture incidence was 60% and H:L ratio was high, with no treatment effect for either measure. This, together with information on faecal corticosterone, feather loss and mortality, suggests that the welfare of birds in all treatments was relatively poor by the end of lay.

1. Eleven broiler chicken farms, representing 4 production system types, were visited during the last 5 d of the flock cycle: bird and flock details were recorded. Litter friability was assessed at 9 sites within the house, atmospheric ammonia was measured at three sites and bird cleanliness was assessed on a numerical rating scale. 2. For these flocks, hock burn, foot burn and breast burn were measured at the processing plant by standardised assessors. 3. Significant correlations were identified between the percentage of birds with foot burn and average litter score, average house ammonia concentrations and feather score. 4. No correlation was found between the percentage of birds with hock burn or breast burn and average litter scores, average ammonia concentrations or feather score. 5. No correlation was found between stocking density and foot burn, hock burn or breast burn.6. If confirmed, these findings may have implications for the draft EU Broiler Directive, for which it is proposed that permitted stocking density on farm may be determined by the incidence and severity of contact dermatitis measured on plant.

1. Based on records of all (n = 59 171 843) broiler chickens slaughtered over three years at one processing plant, the overall mortality of birds in transit was 0.126%. 2. There was a pronounced seasonal effect with increased mortality in the summer months, particularly June, July and August. Mortality increased when the maximum daily temperature (measured in the shade) rose above about 17 degrees C at the start of the summer. 3. Between 17.0 and 19.9 degrees C, mortality was 30% higher than at lower temperatures. Between 20.0 and 22.9 degrees C it increased 2.6-fold, and at temperatures of above 23 degrees C 6.6-fold. There was no evidence of birds dying from hypothermia at very low ambient temperatures (down to -1 degrees C). 4. The implication from the results is that above a maximum daily temperature of 17 degrees C steps may need to be taken to ameliorate the damaging effects of transport on bird welfare.

An eight-point photographic scale from 1 (very clean) to 8 (very dirty) was used to assess the cleanliness of the plumage of 69,783 live broiler chickens delivered in 54 loads to three processing plants which were each visited in spring, summer and winter. There were considerable variations between the plants and between the visits, but most birds were given scores of 6 or 7. The average plant scores were 6.07, 6.56 and 6.84, which were associated with frequencies of birds with scores of 7 or more of approximately 38, 56 and 73 per cent. There was some indication that longer feed-withdrawal times of up to 10 hours were associated with dirtier birds.

A total of 6578 sheep carried in 74 vehicles to one slaughter plant were monitored, and stocking densities, in terms of m2 floor area available per 100 kg liveweight, were estimated from the dimensions of the vehicle pens and estimates of liveweight based on chest girth measurements. The observed stocking densities ranged from 0.29 to 2.00 m2/100 kg liveweight, and the average density was 0.65 m2/100 kg. One per cent of the sheep were carried at estimated stocking densities of less than 0.3 m2/100 kg, 37 per cent at densities between 0.3 and 0.6 m2/100 kg and 57 per cent at densities between 0.6 and 0.9 m2/100 kg. Over 30 per cent of the animals in the survey were transported at densities higher than the working recommendations made by the Farm Animal Welfare Council.

Subjection of broiler chickens to random, narrow band vibration (2, 5, 10 Hz) for 1 h, simulating that experienced during normal road transport, did not significantly influence liver or muscle glycogen concentrations or muscle ultimate pH (pHu). Vibration for 3 h increased body temperature (P<0.05) and decreased (P<0.01) pHu in both 'white' pectoralis superficalis (PS) and 'red' biceps femoris (BF) muscles overall, but did not affect liver or muscle glycogen concentrations. However, higher vibration frequencies resulted in reduced (P<0.05) glycogen concentrations in liver and BF muscle. The conclusion was that vibration was unlikely to be the major cause of muscle glycogen depletion seen in transported broilers, but the reduction in pHu in the PS muscle after vibration may have been related to the similar effect seen in previous studies after normal transport.

Two trials, each involving 56 calves less than one month old, demonstrated that the responses of calves to food and water deprivation during 24 hours of transport were similar to those observed in older cattle and lambs. There was increasing utilisation of body reserves and a measurable increase in dehydration, coupled with an increased loss of liveweight. Feeding 1 litre of glucose/electrolyte solution at eight-hour intervals did reduce the effects of food and water deprivation, but it is suggested that the minor benefits of mid-transport feeding during a 24-hour journey would not justify the disruption that would be caused by unloading and feeding. It would be better to complete the journey in as short a time as possible, providing the calves were carried under suitable conditions. Liveweight and the levels of plasma beta-hydroxybutyrate, non-esterified fatty acids, total protein and albumin had all returned to approximately pre-transport values after 24 hours of recovery. However, the calves had not started to gain in liveweight until some time after 24 but before 72 hours of recovery. The calves did not show the same marked responses in heart rate, plasma cortisol and plasma glucose that are observed in older cattle and in other species. They also appeared to be unable to regulate their body temperature closely, when they were transported during the winter. It is suggested that their lack of response to transport was not because they were unaffected but because they were physiologically unadapted to coping with transport.

A survey of 800 broilers arriving at two commercial slaughterhouses with a combined annual throughput of 40 million birds was carried out. Each plant was visited on four occasions throughout summer and winter and blood samples were collected from 100 broilers at exsanguination throughout the day of each visit. In all, the survey covered 16 lorry loads of broilers delivered to one plant and 20 loads delivered to the other. The blood collected was analysed for packed cell volume (PCV), plasma creatine kinase, total protein, sodium, glucose, osmolality and corticosterone. Based on the measures of PCV, plasma total protein, sodium and osmolality there was no evidence of dehydration amongst the lorry loads of birds delivered to the plants. There were differences between the two plants in the levels of all of the blood variables that were measured, except for those of plasma corticosterone.

Five groups of 20 slaughter sheep of approximately 37.9 kg liveweight were transported by road for either three, nine, 15, 18 or 24 hours and three groups were not transported, one of them being deprived of food and water for 24 hours. Before and after transport the liveweight and various blood variables were measured and heart rate and behavioural observations were recorded from subsets of the animals. With increased journey time there was a decrease in liveweight and an increase in the plasma levels of free fatty acids, beta-hydroxybutyrate and urea; however, the changes over 24 hours were similar to those in the group deprived of food and water. In the transported sheep, the heart rate and levels of plasma cortisol and glucose were increased by the stresses of loading and the initial stages of the journey, but after nine hours the sheep appeared, to some extent, to have adapted. They were able to lie down and did not appear to be physically stressed. Measurements of plasma osmolality, total plasma protein and albumin did not indicate that the sheep had become severely dehydrated after 24 hours of transport but upon their return, feeding and drinking activity was greater than that observed before the journey.

Twenty-four castrated male cattle aged between 12 and 18 months were transported by road for five, 10 or 15 hours, over distances of 286, 536 and 738 km. Half the animals were of Hereford x Friesian breeding and half of 'continental' type. The animals transported for five hours lost 4.6 per cent of their bodyweight, those transported for 10 hours lost 6.5 per cent and those transported for 15 hours lost 7.0 per cent; recovery to pre-transport values took five days. There was little evidence from changes in blood composition that a 15-hour journey was more stressful than a 10-hour journey. The cortisol concentrations were increased by the stresses of loading and the first part of the journey but then recovered as the journey continued. Creatine phosphokinase (CPK) activities increased progressively with the longer journeys and CPK, urea, albumin and osmolality levels recovered more slowly after the longer journeys. Increases in free fatty acids, beta-hydroxybutyrate and urea concentrations and the continued increase in urea levels after the end of the journeys suggested that the animals' normal pattern of feeding was disrupted. Increases in albumin, total plasma protein and osmolality indicated slight dehydration during transit which was quickly rectified by access to water. The two breed types responded similarly to transport, except that the increases in CPK were greater in the continental breeds, possibly as a result of their greater muscularity or greater sensitivity to stress. Based on the physiological measurements made and the subjective observations of behaviour a 15-hour transport period under good conditions is not unacceptable from the viewpoint of animal welfare.

In order to provide information on the state of hydration of broilers during marketing, 7-week-old Ross broilers of mixed sex were kept at 17 or 23 degrees C and deprived of food, or food and water, for 24 h. Measurements were made of live weight, carcass weight, muscle moisture, packed cell volume, plasma glucose, corticosterone, total protein, osmolality and sodium. There was a decrease in live weight, carcass weight, plasma glucose and plasma total protein, and an increase in packed cell volume and corticosterone, in birds deprived of food, or food and water. Muscle moisture increased in birds deprived of food and decreased in birds deprived of food and water. Osmolality decreased in birds deprived of food, the decrease being greater in birds at 23 degrees C. Plasma sodium levels were higher in birds kept at 23 degrees C and increased only in birds deprived of food and water at 23 degrees C.

The computerised records of all the lambs slaughtered at one plant from August 1991 to July 1992 were used to determine the mortality rate throughout the year and to examine the variables that could have been associated with changes in the mortality rate. The plant processed 3.3 per cent of all the lambs that were slaughtered in the United Kingdom during the period. Lambs arriving for slaughter from a livestock auction were over four times more likely to die in lairage, or to have died during transport, than lambs which were sent directly from the farm. However, the overall mortality rate was only 0.0182 per cent and lower than that for other species for which figures were available. Changes in the mortality rate of the lambs from livestock auctions appeared to be associated with the price of slaughter lambs, and periods of increased mortality coincided with increased rates of carcase condemnations due to 'arthritis', 'abscess' and 'pleurisy'.

Of 2.9 million pigs transported to seven slaughter plants in 1991 and 1992, 1781 (0.061 per cent) died in transit and 314 (0.011 per cent) died subsequently in the lairage. Overall mortality for both years was 0.072 per cent and mortality in 1992 was 0.066 per cent. There was little seasonal variation in the number of pigs dying in lairage, but more pigs died in transit in months when the weather was hotter. The relationship with temperature was curvilinear; above about 15 to 17 degrees C the detrimental effect of high temperatures was far more serious. In 1992, the year for which complete data were available, average mortality in the seven plants ranged from 0.045 to 0.093 per cent, but this variation was not related to the size of the plant. The number of pigs which died in lairage, rather than in transit, ranged from 4 to 21 per cent of all deaths in the different plants, and the average was 15 per cent. The variation might be related to differences in average lairage times or to the policies of individual plants with regard to moribund pigs. The survey provided no evidence that the mortality among transported pigs has increased over the last 20 years.

Two commercial lorry consignments of 500 sheep were followed from the United Kingdom to their destinations in southern France, one journey of 800 miles taking 18 hours and the other of 950 miles taking 24 hours. Measurements were made of liveweight and skinfold thickness, and blood samples were taken from 100 sheep in each consignment, two days before departure and again immediately after the journeys. The results from each consignment were similar. High levels of plasma beta-hydroxybutyrate, free fatty acids and urea, both before and after the journeys, indicated that the animals were in a catabolic state. Before the journey this was probably as a result of their marketing through livestock auctions. After the journey the animals showed evidence of dehydration, indicated by increased levels of plasma total protein and albumin, and increases in plasma osmolality and skinfold thickness. The behaviour of the sheep after the journeys indicated that they were all alert and physically fit; they showed great interest in any food that was available and were only secondarily interested in drinking, and then resting.

Several behavioural measures were used to determine fearfulness and fatigue in broiler chickens subjected to fasting and/or transportation. There was considerable variability between four replicates, although measures within replicates were acceptably consistent. There was no uniform effect of fasting or transport on behaviour. The most cogent results were obtained by monitoring post-journey behaviour. In the few hours after transport, fasted and transported birds stood more than control birds which could be explained by increased food-searching behaviour and/or arousal. It is argued that the high variability between replicates indicates that considerable efforts must be made to control environmental variables in studies of behaviour after transporting chickens.

The effects of nine and 14 hours of road transport and the subsequent recovery in lairage of 392 hill lambs were studied in August and November. The gathering and the handling of the lambs were stressful, both physically and psychologically, and the journey imposed further psychological and metabolic stress. The levels of noise in the trailer were high (90db[A]). There were no measurable differences between the responses of the lambs transported for nine or 14 hours and there appeared to be three stages in their recovery after transport. After the first 24 hours of lairage changes in the blood components usually associated with short term stress and dehydration had recovered; after 96 hours there had been a well defined recovery of liveweight and the levels of most of the metabolites measured appeared to have stabilised and after 144 hours the lambs had recovered almost completely, most of the creatine phosphokinase had been cleared from the plasma and their plasma protein levels had stabilised.

Broilers were either not transported or were transported for 2, 4 or 6 hours after having been subjected to food withdrawal times of less than one hour or of ten hours. The birds were then slaughtered using normal commercial practices. The longer period of food deprivation reduced liver weight and glycogen content, and circulating glucose concentrations. It also elevated the ultimate pH value (pHu) in the biceps muscle and by implication, therefore, reduced its glycogen content. With longer journey times, liver weight and glycogen content decreased. Transport had an inconsistent effect on glycogen concentration in the pectoral muscle but progressively reduced its pHu. In contrast, pHu in the biceps progressively increased, by implication because transport depleted muscle glycogen levels. Birds transported further had higher concentrations of total protein in their plasma which, though this was not significant, also had a higher osmolality. This suggests that transported birds became dehydrated. Additionally, the depletion of body glycogen stores might be associated with the perception of fatigue.

Two experiments were carried out in which a total of 602 pigs were slaughtered after being held in lairage for periods ranging from less than one hour to 21 hours. In the first experiment the pigs were handled under ideal conditions and slaughtered at the University of Bristol slaughterhouse; in the second the pigs were killed at a commercial plant. Blood samples collected at exsanguination were analysed for indices of stress. There were no consistent effects of time in lairage on the levels of lactate and creatine phosphokinase. Plasma cortisol and beta-endorphin levels were reduced by lairage for three hours or more in the first experiment and cortisol was reduced by lairage for two hours or more in the second; beta-endorphin was not measured in the second experiment. A period of rest in lairage allowed the pigs to recover from transport and the associated handling and the recovery appeared to be complete within two to three hours.

Pigs could be moved along a race 120 cm wide more quickly than along a race 45 cm wide. The presence of a bend with an angle of 45 degrees slowed their progress by about 10 per cent, a bend of 90 degrees or 120 degrees slowed them by 19 per cent and a 180 degrees bend slowed them by 44 per cent. There was little evidence of any interaction between the effects of width and angle of bend; the effect of a sharp bend could not be compensated for by increased width. The pigs became accustomed to the races and moved more quickly in later runs.

Newly hatched chicks were kept for up to 48 hours without food and water and compared with a control group of chicks given access to food and water within six hours of hatching. The deprived chicks progressively lost body water and developed increases in plasma total protein concentration consistent with a decrease in plasma volume. They demonstrated a stronger motivation to drink and drank more when offered water, suggesting that they had become dehydrated. There was evidence, however, that normally access to food was necessary to initiate drinking. The deprived chicks continued to rely on fat metabolism to supply their energy needs whereas the fed birds showed rapid reductions in circulating levels of beta-hydroxybutyrate and increases in plasma glucose and liver glycogen concentrations, indicating a change to carbohydrate-orientated energy metabolism. The deprived chicks lost weight at an average of 0.14 g/hour and weighed 16.5 g less than the fed chicks after 48 hours.

In experiments to investigate the time taken by pigs to negotiate ramps with different slopes it was found that they ascended with greater facility than they descended. Between 0 degrees and 20 degrees, the slope appeared to have little effect on the time taken to ascend or descend. Above 20 degrees the time taken to ascend increased linearly. The relationship between the time taken to descend and the slope above 20 degrees was biphasic with times increasing substantially above 35 degrees. There were also differences between the times taken on different days but no evidence of habituation. Pigs took longer to climb steeper ramps with wider spaces between cleats but there was no significant effect on the time taken to descend.

Meat from pigs given the beta-adrenergic agonist Salbutamol was assessed by a trained taste panel. Overall, there were no significant effects of Salbutamol on panel scores for pork flavour, foreign flavour or overall acceptability. Although the differences were also not significant, meat from treated pigs was rated slightly tougher (P = 0·10) but more juicy (P = 0·14) than that from untreated animals. This concurred with higher instrumental values for toughness although the correlation between taste panel and instrumental texture measurements was low (r = 0·36, P < 0·001)., (Copyright © 1991. Published by Elsevier Ltd.)

Conductivity measurements made with the Tecpro Pork Quality Meter at either 45 min or about 20 h post mortem on 224 pig cacassees which exhibited a wide range of raw meat quality were moderately correlated with initial pH (pH(45); r = 0.54 and 0.62) but less well correlated with reflectance (r = 0.32 and 0.37), drip loss (r = 0.34 and 0.47 and other objective measures of meat quality in the M. Longissimus dorsi. Measurements did not allow differentiation between normal and dark, firm, dry (DFD) meat but were of some value in identifying carcasses producing potentially pole, soft, exudative (PSE) meat. In the UK they would be more useful for monitoring meat quality in large groups or populations of pigs, than for categorising individual carcasses for grading on technological purposes., (Copyright © 1991. Published by Elsevier Ltd.)

The minimum distance transported, the journey time and the total marketing time were estimated for 5819 journeys in which 19.3 million broilers were transported to four processing plants. The average distance travelled was 33.5 km, the average journey plus unloading time was 2.7 hours and the average total marketing time, from the start of loading to the completion of unloading, was 3.6 hours. The maximum recorded journey plus unloading time was 12.1 hours and the maximum recorded total marketing time was 12.8 hours. There was considerable variation between plants, those with smaller annual throughputs tending to have longer average times. In 46 per cent of journeys the birds were unloaded within three hours of the start of loading, in 78 per cent within five hours and in 94 per cent within seven hours of the start of loading.

The times spent in transport and lairage by 124,036 lambs slaughtered in two plants in the south of England were recorded. About half of them travelled for up to 120 km, taking up to four hours, and three-quarters travelled not more than 300 km, the journeys taking up to about six hours. Bimodal frequency distributions of lairage time were apparent; overall one third of the lambs spent up to four hours in lairage but more than 40 per cent were kept for longer than 14 hours, while they were held overnight. Early season lambs tended to travel shorter distances to slaughter and spent less time in lairage than late season lambs. The average total times spent in transit and lairage were 22.3 hours and 13.3 hours at the two plants.

Eight slaughterplants with throughputs ranging from 20 to 300 animals per day were examined to estimate the incidence of dark cutting beef in the United Kingdom. Four thousand, eight hundred and sixteen animals were surveyed and information concerning animal category, source, season and preslaughter handling conditions recorded. Muscle samples were removed to estimate glycogen concentration and after incubation, ultimate pH. The overall incidence of dark cutting (pHu ≥ 6·0) was 4·1%. Increased incidence was associated with short (≤ 20 miles) and long (≥ 150 miles) transport distances. Slaughter on the day of arrival rather than overnight lairage also increased the incidence. Plants were classified into small (killing ≤ 50 animals per day) or large (killing ≥ 100 per day). Eighty per cent of the animals slaughtered passed through the large plants, and a higher incidence was also associated with these plants. Bulls had the highest incidence and heifers the lowest. A seasonal effect was recorded with the highest incidence found between July and October. The results, however, indicate that factors in addition to those examined are also important., (Copyright © 1990. Published by Elsevier Ltd.)

The characteristics of backfat were measured in carcasses from 233 pigs representing eleven breeds. Animals were fed ad libitum and killed at an average live weight of 62 kg. In breeds in which the backfat was thicker it was also firmer and contained less water. In leaner breeds there was reduced cohesiveness of fat and muscle components of the loin joint so that the fat separated more easily from the underlying lean. This contributed to joints which were subjectively assessed as less firm and well set. Fatter breeds tended to have Longissimus muscles which contained more intramuscular fat. However, the relationship between muscle fat and carcass fat was poor suggesting that, if it was thought desirable to select for increased intramuscular fat in the interests of meat palatability, then this could be achieved without making carcasses undesirably fat. Differences in fat characteristics between breeds were apparently largely attributable to differences in fatness rather than inherent breed factors., (Copyright © 1990. Published by Elsevier Ltd.)

Duroc and halothane negative British Landrace boars and gilts were performance tested from 30 to 80kg on ad-libitum or restricted feeding regimes, with like-sexed non-littermate groups of pigs penned together. Meat and eating quality was determined using objective laboratory measurements and by taste panel and consumer panel assessment on 160 pigs with 20 full-sib families for each breed, and two boars and two gilts per family. Duroc M. longissimus(†) was darker in colour, had a more intense, redder colour and contained more fat and less moisture than Landrace muscle. Duroc subcutaneous fat was less firm, had a higher water content and concentrations of linoleic acid and lower concentrations of stearic acid than Landrace fat. The taste and consumer panels scored Duroc meat as being more juicy, but less tender, having poorer flavour and being less acceptable than Landrace meat. The higher juiciness scores of Duroc meat were probably attributable to the higher intramuscular fat content compared to Landrace meat. Duroc boars had lower values for flavour liking and acceptability compared to other breed-sex combinations which may be due to the particular fatty acid composition of the subcutaneous fat in Duroc boars., (Copyright © 1990. Published by Elsevier Ltd.)

Variation in chemically determined total haem pigment concentration and instrumentally determined colour was examined in 223 samples of M. longissimus dorsi (LD) representative of the majority of slaughter pigs currently produced in the UK. Whether pigs were sired by White (Large White or Landrace) or Meat-line boars did not affect any measured characteristic but source breeding company influenced total haem pigment concentration (P < 0·01). Haem pigment concentration was higher in muscles from gilts, compared with castrates, boars being intermediate. Gilts also had darker muscles, based on EEL Reflectance values (P < 0·05), and lower hue values (P < 0·05). When compared with animals fed ad-libitum, restricted-fed pigs had higher concentrations of muscle haem pigment (P < 0·001) and this resulted in meat that was slightly darker (P < 0·05), despite having lower ultimate pH (pHu) (P < 0·05), and had a lower hue value (P < 0·001). Measurements of reflectance, total soluble protein and pHu indicated that differences in the incidence of potentially pale, soft, exudative or dark, firm, dry muscle were unlikely to be important contributors to variation in the colour of the meat in this study., (Copyright © 1990. Published by Elsevier Ltd.)

In order to elucidate the mechanism of drip formation, measurements have been made of the amount of drip, and its protein concentration, from 80 pigs chilled conventionally. The correlation between amount of drip and protein concentration was poor but significant (r = -0·41, P < 0·001). The individual protein components of 20 drip samples were analysed by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). Relative protein composition varied with amount of drip. As the amount of drip increased above about 12% the absolute amounts of some proteins decreased; these proteins were creatine kinase and/or phosphoglycerate kinase (under the system used, these two proteins comigrate and therefore cannot be distinguished), myokinase, and an unidentified protein of molecular weight 137000. Drip contained similar proteins to a sarcoplasmic extract and in similar amounts. These results show that drip is mainly sarcoplasmic in origin and we suggest that the systematic changes in individual proteins as the amount of drip increases may be explained by denaturation of some or all of these proteins and possibly by dilution with fluid from within the myofibril., (Copyright © 1990. Published by Elsevier Ltd.)

About 40 to 60 per cent of the total blood volume is lost at exsanguination. The loss can be influenced slightly by differences in traditional slaughter techniques and is considerably reduced after cardiac arrest in sheep and cattle. Blood not lost at sticking is probably largely retained in the viscera rather than the carcase. The residual blood content of lean meat is 2 to 9 ml/kg muscle. There is no evidence that this amount is affected by different slaughter methods or that large amounts of residual blood influence the microbiology of meat.

The relationships between sarcoplasmic, myofibrillar and total soluble protein (sarcoplasmic + myofibrillar) concentrations, and subjective (colour-structure score) and objective (drip loss and reflectance) measures of lean meat quality were determined using 100 samples of M. Longissimus dorsi that showed a wide range of quality. There was good agreement between the subjective and objective assessments of quality. Overall, the concentration of soluble sarcoplasmic proteins showed the highest correlations with quality assessments. The relationships with total soluble protein were poorer and were least good with myofibrillar protein concentration. Sarcoplasmic protein concentration was also the best potential predictor of meat quality when pale, soft, exudative (PSE) muscles were excluded from the sample. However, if dark, firm, dry (DFD) muscles were excluded instead, the concentration of total soluble protein was as good as, or better than, sarcoplasmic protein as a potential predictor of quality, particularly muscle reflectance., (Copyright © 1989. Published by Elsevier Ltd.)

Small samples of liver and m. adductor (AD) were collected within 45 minutes of death from the carcasses of a total of 604 pigs killed at three bacon factories. Glycogen concentrations were measured and part of the muscle sample allowed to complete post-mortem glycolysis in order to estimate ultimate pH (pHu) values. Liver glycogen levels were also used to predict overall food withdrawal times. Muscle glycogen concentrations ranged from 2.2 to 15.3 mg/g, liver glycogen from 0.01 to 50.7 mg/g and pHu in the AD from 5.51 t 6.76. The overall average predicted fasting time was 16.5 +/- 0.54 (SEM) hours and 22% of pigs had pHu values in the AD greater than 6.2 indicative of potentially dark, firm, dry meat. Muscle glycogen concentration was positively correlated with liver glycogen (r = 0.27, P less than 0.01) and negatively correlated with predicted fasting time (r = -0.30, P less than 0.001). The pHu in the AD was negatively correlated with liver glycogen (r = -0.34, P less than 0.001) and positively correlated with predicted fasting time (r = 0.37, P less than 0.001). Therefore, pigs which had reduced concentrations of glycogen in their livers, indicative of longer food withdrawal times before slaughter, tended to have less glycogen in their muscles and a higher pHu in the meat.

From estimates of the residual blood content of muscles from rats killed while stressed or under barbiturate anaesthesia it appears that, at slaughter, the stress associated with stunning and exsanguination will normally produce peripheral vasoconstriction through the action of released catecholamines. This will result in minimal retention of blood in the skeletal muscles while factors which reduce vascular tone will lead to higher levels of residual blood in meat., (Copyright © 1978. Published by Elsevier Ltd.)

Pigs of stress-resistant and stress-susceptible breeds were reared either under intensive conditions in bare concrete pens or extensively under environmentally enriched conditions in an outside paddock. They were slaughtered at either 60 or 90 kg live weight. Rearing environment had no effect on the ability of the pigs to respond to the stress of preslaughter handling based on measurements of adrenal ascorbic acid and plasma cortisol. Neither did it influence initial or ultimate pH or the water holding capacity of the meat. Pigs reared outside had thinner backfat and slightly darker meat. The latter was not attributable to differences in haem pigment concentration. Overall, differences due to rearing environment were slight and not commercially important., (Copyright © 1983. Published by Elsevier Ltd.)