Electric Goad Research Articles

Handling, Electric Goad, and Head Restraint: Effects on Calves' Behavior

Ninety-six weaned calves (48 bulls and 48 heifers) were allocated in a 2 ×2 ×2 arrangement to 3 treatments each with 2 levels: calves handled every 10 days or 20 days; an electric goad used or not used; and head gate restrained or not restrained. Behavior responses were measured by 5 incremental progressive force requirement (PFR) categories and transit time (TT). The PFRs were transformed to maximum force scores (MFS) for analysis (Snell, 1964). TT was the time taken for calves to move 11 m along a chute. During the study, 52%, 36%, 5%, 3%, and 5% of the cattle were observed in Categories 1, 2, 3, 4, and 5, respectively. Cattle handled every 10 days showed a 36.0% higher MFS (p < .03) and a 24.5% higher TT (p < .02) than cattle handled every 20 days. The MFS and TT for head gate-restrained calves were 33.0% (p < .03) and 15.5% higher (p < .02), respectively, compared to calves not restrained in the head gate. Cattle developed a reluctance to frequent handling early in the study and an aversion to head gate restraint midway. The aversion was pronounced when calves were handled frequently and head gate restrained simultaneously. Handling, goad, and head gate restraint had no effect (p > .05) on weight gain. The aversion to the head gate was more pronounced in bulls than in heifers. Cattle habituated well to frequent handling, but when combined with a head hold they became more difficult to handle. Management practices such as restraining cattle in the head gate should be done infrequently, thereby improving the welfare of calves.

Comparison of different dietary magnesium supplements on pork quality

Forty-eight crossbred (Large White×Landrace) boars were used to compare the effect of dietary magnesium aspartate (MgAsp), magnesium sulphate (MgSO 4) and magnesium chloride (MgCl 2) on muscle glycogenolysis and pork quality. The pigs were fed finisher feed supplemented with either MgAsp, MgSO 4 and MgCl 2 for 5 days prior to slaughter. At the abattoir, all pigs received 15 electric shocks from an electric goad 5 min prior to slaughter. Pigs fed the diet supplemented with MgSO 4 had the highest plasma Mg concentrations at slaughter in comparison with pigs fed the MgAsp and MgCl 2 supplemented diets. There were no differences in plasma adrenaline and noradrenaline concentrations at slaughter between the different diets. Pigs fed the Mg diets had higher muscle glycogen concentrations in the Longissimus thoracis (LT) muscle at 5 min and at 40 min (except MgCl 2) post-slaughter compared to pigs fed the control diet. Also pigs fed the Mg diets had lower muscle lactic acid concentrations in the LT at 5 min post-slaughter and lower drip loss at 24 hr post-slaughter compared to pigs fed the control diet. These results indicate that cheaper magnesium sources, MgSO 4 and MgCl 2, are as efficacious as MgAsp in reducing drip loss and improving pork quality.

Effect of mixing boars during lairage and pre-slaughter handling on pork quality

Forty-eight crossbred (Large White × Landrace) boars were used in a 2 × 2 factorial design to determine the effects of mixing unfamiliar pigs during lairage and the use of electric goads just prior to slaughter on muscle glycogenolysis and subsequent pork quality. The treatments included 2 mixing treatments (familiar pigs kept together during lairage and unfamiliar pigs mixed during lairage) and 2 handling treatments [minimal handling and negative (electric goad) handling pre-slaughter]. Pigs mixed during lairage had lower muscle glycogen and lactic acid at 5 min, 40 min, and 24 h post-slaughter than familiar pigs kept together during lairage. Mixing of unfamiliar boars also resulted in higher ultimate muscle pH, a higher incidence of dark, firm, dry (DFD) pork, and a lower incidence of pale, soft, exudative (PSE) pork compared with familiar pigs kept together during lairage. The use of an electric goad prior to slaughter did not affect muscle glycogen in mixed pigs, but in unmixed pigs there were large numerical diffferences in glycogen concentrations. The negatively handled unmixed pigs had a trend for lower glycogen concentrations which did not reach significance. This was probably due to the small sample size. However, pigs negatively handled pre-slaughter had higher lactic acid concentration at 5 min post-slaughter compared with minimally handled pigs. This experiment has demonstrated that mixing of unfamiliar boars can have a major impact on pork quality, resulting in a high incidence of DFD pork and a reduced incidence of PSE.

The Effect Of Handling Pre-Slaughter And Carcass Processing Rate Post-Slaughter On Pork Quality

Forty-eight male crossbred (Large White—Landrace) pigs were used in a 2×2 factorial design to determine the effect of pre-slaughter handling (minimal and negative handling prior to slaughter) and the rate of carcass processing post-slaughter [normal rate (45 min) and delayed rate (70 min) from time of exsanguination to carcass entering the chiller] on muscle glycolysis and pork quality. Pigs negatively (using an electric goad) handled at the abattoir just prior to slaughter had lower muscle glycogen concentrations in the Longissimus thoracis (LT) and the Biceps femoris (BF) at all times post-slaughter and lower lactic acid at 5, 45 and 70 min post-slaughter compared to pigs minimally (no use of electric goads) handled prior to slaughter. Negative handling of pigs just prior to slaughter also resulted in pork which had higher surface exudate and a higher incidence of PSE compared with pigs minimally handled prior to slaughter. A prolonged rate of carcass processing resulted in reduced muscle glycogen in the LT and BF at all times post-slaughter. Delays in carcass processing rate also affected pork quality, as the meat was paler in comparison with pig carcasses that were processed without any delays. The results from this experiment have indicated that the use of electric goads to move pigs at the abattoir, and delays in carcass processing post-slaughter, can have a detrimental influence on ultimate pork quality.

Observations on behaviour and skin damage of slaughter pigs and treatment during lairage

In five Dutch and four Belgian slaughterhouses the following elements were studied: (1) slaughterhouse husbandry practice, (2) agonistic behaviour in groups of pigs, (3) indices of skin damage following slaughter recorded on a relative scale of 1–4 where 4 indicates severe damage. Variation in slaughterhouse husbandry practice was considerable (stocking density range, 1.0–3.1 pigs m −2; range of time spent in lairage prior to slaughter, 0–3 h). Brooms and/or electric goads were used to move pigs in all slaughterhouses and in one Dutch abattoir handling with sticks seemed to contribute considerably to skin damage. The level of agonistic behaviour was lowest during the first 10 min in lairage. In the Dutch slaughterhouses, large individual differences in aggression between pigs were observed. Pigs in Belgian slaughterhouses were tranquillized prior to transport, resulting in generally low levels of agonistic behaviour. The percentage of resting animals increased steadily up to an average of 36% in the Dutch abattoirs and 45% in the Belgian abattoirs after 1.5 h. In both the Dutch and the Belgian slaughterhouses, skin damage was higher in the front (2.3 ± 0.1 and 2.1 ± 0.3, respectively) and in the middle region (2.2 ± 0.2 and 2.1 ± 0.2, respectively) than in the hind region (1.7 ± 0.1 and 1.4 ± 0.2, respectively) of the pig. For the Dutch slaughterhouses, skin damage was significantly associated with time kept in lairage ( P < 0.05) and with stocking density ( P < 0.05). It is suggested that to decrease aggression and skin damage and thus to increase welfare in the Dutch slaughterhouses visited, stocking density should be lower and pigs should be slaughtered as soon as possible after arrival.

Factors influencing the welfare and carcass and meat quality of pigs 1. The effects of stocking density in transport and the use of electric goads

ABSTRACTThis experiment was designed to study the effects of stocking density in transit and the use of electric goads on pig welfare and subsequent meat quality. Sixty-four pens, totalling 1400 commercial crossbred hybrid pigs, were transported from a farm to a large commercial abattoir at either high (0·3 m2 per pig) or low (&gt;0·4 m2 per pig) stocking densities. The lorry drivers loaded and unloaded the pens of pigs at either end of their journey with, or without, an electric goad. Similarly, lairage men moved groups of pigs from their lairage pens to the stunning and slaughter area with, or without, goads. Consequently, eight possible treatment combinations arose from this 2 × 2 × 2 factorial experiment. About 20 h after slaughter, the fibre optic probe (FOP) value of the longissimus dorsi muscle was recorded and carcasses were scored for the extent of skin blemish. Pigs in high stocking density groups (HSD) had lower FOP values than those on low stocking density groups (LSD) (P &lt; 0·05) and more severe skin blemish (P &lt; 0·001). The effect of goading in transport or in the lairage, had no significant effect on the FOP values. However, the skin blemish data showed a significant interaction between the use of goads during transport and the stocking density treatment (P &lt; 0·05). This interaction implied that the use of goads when loading pigs at a HSD was associated with a reduction in skin blemish. Conversely, the lowest skin blemish frequency was observed in the LSD treatment group handled without the aid of goads. Pigs in the HSD groups were visibly more skin damaged and exhibited evidence of rectal prolapse which was absent in pigs transported at LSD. Lower stocking densities are to be recommended as carcass, meat quality and pig welfare are probably improved. The use of goads is associated with a higher degree of carcass damage unless pigs are to be densely packed during transport.

Changes in blood acid-base characteristics, haemoglobin and lactate concentrations due to increasing moderate stress in pigs.

Blood samples were collected by indwelling ear vein catheter from pigs (100 kg body weight) at rest and at different stages of increasing moderate stress. The stress increased from being forced to stand to fixation by maxillary sling alone and combined with stimulation with an electric goad. Stress caused significant decreases in blood pH, base excess and, at lower levels of significance, standard bicarbonate, while pCO2 and lactate increased significantly. Respiration rate was not affected. It is concluded that stress caused a combined respiratory and metabolic acidosis, although both components of the acidosis might originate from changes in muscle metabolism. (Abstract retrieved from CAB Abstracts by CABI’s permission)

Science and the Welfare of Animals

A SCIENTIFIC Investigations Committee has been formed by ULAWS (University of London Animal Welfare Society), which is in the course of being incorporated into the newly formed Universities Federation for Animal Welfare. The committee will concern itself with the acquisition of knowledge calculated to benefit animals in their own interests as distinct from the interests of the human species. Its functions will be to define problems for inquiry, to advise as to the allocation of funds for the purpose, and to collect and communicate any new knowledge which may be of value for increasing the well-being or diminishing the sufferings of animals. A small grant has been made in aid of an ecological investigation relevant to the control of wild populations, which is frequently carried out by methods considered by many to be inhumane. Among the other topics in which the committee is interested are the widespread failure to utilize existing knowledge o dietetic principles ; the problem of bait poisons the destruction of sea-birds by oil waste ; and the use of an electric goad as a substitute for the stick in droving cattle. The members of the committee are: Capt. C. W. Hume (chairman), Dr. S. Graham Brade-Birks (hon. secretary), Dr. Paul Haas, Mr. H. R. Hewer and Dr. W. B. Wooldridge. Men of science who are in sympathy with the objects of the co mittee are invited to communicate with Dr. S. Graham Brade-Birks, South-Eastern Agricultural College, Wye, Kent.