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Biomedical subjects

E Lambooij

Publications and source records attributed to E Lambooij.

At least 19 recordsLinked to original sources
PubMed2002

Effects of feed deprivation and electrical, gas, and captive needle stunning on early postmortem muscle metabolism and subsequent meat quality.

The general method for stunning poultry before slaughter is by immersion of a chicken's head into an electrified waterbath. This method results in carcass and meat quality deficiencies. The major problems are hemorrhages and a delay in onset of rigor mortis, which increases the risk of cold shortening with early deboning. In two experiments, this study examines the early postmortem metabolism in the breast muscle and its effect on ultimate meat quality. The first experiment describes the effects of 5 h feed deprivation on the availability of glycogen from the liver and the breast muscle, of waterbath and head-only electrical stunning on pH and metabolite levels up to 6 h in unprocessed muscle, and the consequences on meat quality. The second experiment compares the same measurements after waterbath and head-only electrical stunning, CO2/O2/N2 and Ar/CO2 gases, and captive needle stunning. Metabolic degradation halted after 6 h without processing or after 4 h under conventional conditions after waterbath and CO2/O2/N2 stunning. With other stunning methods, this occurrence is at a faster rate, largely depending on muscle activity. Muscle glycogen does not need to be exhausted for energy generation to cease. If glycogen is a limiting factor, as found with head-only stunning, pH drops too rapidly and affects water-holding capacity and color. Hemorrhage scores were higher with electrical stunning than with other stunning methods. Gas stunning affected color and, to a lesser extent, water-holding capacity. Captive needle stunning scored between gas and electrical stunning on most measurements.

Abattoirs↗
PubMed2002

Development of brain damage as measured by brain impedance recordings, and changes in heart rate, and blood pressure induced by different stunning and killing methods.

Poultry are electrically stunned before slaughter to induce unconsciousness and to immobilize the chickens for easier killing. From a welfare point of view, electrical stunning should induce immediate and lasting unconsciousness in the chicken. As an alternative to electroencephalography, which measures brain electrical activity, this study used brain impedance recordings, which measure brain metabolic activity, to determine the onset and development of brain damage. Fifty-six chickens were surgically equipped with brain electrodes and a canula in the wing artery and were subjected to one of seven stunning and killing methods: whole body electrical stunning; head-only electrical stunning at 50, 100 or 150 V; or an i.v. injection with MgCl2. After 30 s, the chickens were exsanguinated. Brain impedance and blood pressure were measured. Extracellular volume was determined from the brain impedance data and heart rate from the blood pressure data. An immediate and progressive reduction in extracellular volume in all chickens was found only with whole body stunning at 150 V. This treatment also caused cardiac fibrillation or arrest in all chickens. With all other electrical stunning treatments, extracellular volume was immediately reduced in some but not all birds, and cardiac fibrillation or arrest was not often found. Ischemic conditions, caused by cessation of the circulation, stimulated this epileptic effect. A stunner setting of 150 V is therefore recommended to ensure immediate and lasting unconsciousness, which is a requirement for humane slaughter.

Animals↗
PubMed2002

Effects of feed deprivation and transport on preslaughter blood metabolites, early postmortem muscle metabolites, and meat quality.

In practice, poultry have their feed with drawn several hours before being collected and put on transport to the slaughter plant. With the exhaustion of their internal energy stores, the chickens may lack energy to cope with the conditions to which they are subjected. Meat quality is affected by the energy stored in the muscle at time of slaughter and its rate of decrease postmortem. Of 320 broiler chickens, half were subjected to 5 h feed deprivation whereas the others had access to feed until transport. In both groups, half the chickens were transported for 1.5 h, and the rest were transported within 5 min to the on-site slaughter facility. Twenty chickens were equipped with an ultrafiltration-collection device for monitoring glucose and lactate profiles. After slaughter, liver pH was measured. Stimulation of muscle metabolism was minimized by avoiding plucking. Breast muscle samples were taken at 0, 1, 2, 4, and 6 h and analyzed for pH and metabolite concentrations, and meat quality was measured at 96 h. Although liver glycogen was depleted in feed-deprived chickens, feed deprivation and transport for short periods were not found to affect blood glucose or lactate levels nor glycogen levels in the muscle at slaughter. Muscle carbohydrate metabolism was found to come to a complete halt after 6 h, which was not caused by exhaustion of the glycogen store but by the muscle's ability to generate adenosine triphosphate (ATP) after 4 h. At this time, rigor mortis had set in and deboning could be done without risk of cold shortening.

Abattoirs↗
PubMed2000

[Review of the production of ostrich meat].

Ostrich meat was originally considered to be a by-product of the leather industry. Ostrich farming focused on the production of good quality hides and was mainly based on experience. Since a few years there has been a move from hide production to meat production; however, little is known about ostrich meat production which has consequences for legislation. There is insufficient knowledge about the factors influencing muscle growth. The strong growth of ostrich meat production in the EU member states should be discussed because the climatic conditions are not optimal and the price of the meat may remain high compared to meat of broilers, pigs, and cattle. Information programmes have to be set up for all members in the production chain. The present method for stunning of ostriches has to be changed in most slaughterhouses. In this study the effects of electrical and mechanical stunning on unconsciousness, duration of unconsciousness, behaviour, and meat quality parameters were examined. At least 500 mA is needed to stun ostriches effectively, and they can be killed using a short-stick interval or a long stunning duration. A modified captive needle pistol, using air pressure, is an alternative to electrical head-only stunning.

Abattoirs↗
PubMed2000

Effects of environmental enrichment on behavioral responses to novelty, learning, and memory, and the circadian rhythm in cortisol in growing pigs.

Previously we showed that pigs reared in an enriched environment had higher baseline salivary cortisol concentrations during the light period than pigs reared under barren conditions. In the present experiment, it was investigated whether these higher baseline salivary cortisol concentrations were a real difference in cortisol concentration or merely represented a phase difference in circadian rhythm. The effects of different cortisol concentrations on the behavioral responses to novelty and learning and long-term memory in a maze test were also studied in enriched and barren housed pigs. At 9 weeks of age enriched and barren housed pigs did not differ in baseline salivary cortisol concentrations nor in circadian rhythm, but at 22 weeks of age barren housed pigs had a blunted circadian rhythm in salivary cortisol as compared to enriched housed pigs. The differences in baseline salivary cortisol concentrations between enriched- and barren-housed pigs are age-dependent, and become visible after 15 weeks of age. Enriched- and barren-housed piglets did not differ in time spent on exploration in the novel environment test. Barren-housed pigs had an impaired long-term memory in the maze test compared to enriched-housed pigs; however, no differences in learning abilities between enriched- and barren-housed pigs were found. Because blunted circadian cortisol rhythms are often recorded during states of chronic stress in pigs and rats or during depression in humans, it is suggested that the blunted circadian rhythm in cortisol in barren-housed pigs similarily may reflect decreased welfare.

Aging↗
PubMed2000

Behavioral responses of broilers to different gaseous atmospheres.

This study was conducted to determine the differences in behavioral response of broilers when they come into contact for the first time with gas mixtures that can be used for stunning. The six test groups were divided into four experimental groups that were exposed to gas mixtures used for stunning and two control groups that were exposed to atmospheric air. The different gas mixtures and their concentrations were a) air, no flow (control-); b) circulating air, flowing (control+); c) >90% Ar in air; d) 60% CO2 in air; e) 40% CO2 and 30% O2 in air; and f) 70% Ar and 30% CO2 in air. The behavior of the broilers before entering the gas tunnel, the number of birds that moved into the gas mixture, and the behavior in the gas mixture were recorded on video and analyzed afterward. No differences among the groups were observed in the number of broilers that walked into the gas tunnel or in the number of birds that tried to return to the cage. Exposure of broilers to the 70% Ar and 30% CO2 mixture resulted in the fastest loss of posture. The number of broilers exhibiting headshaking and gasping was least in the >90% Ar in air mixture. Convulsions were rarely seen in the 40% CO2 and 30% O2 mixture; the other gas mixtures resulted in severe convulsions. The experiment did not indicate that broilers could detect or avoid increased CO2 or decreased O2 levels when they come into contact with such atmospheres for the first time.

Administration, Inhalation↗
PubMed2000

Electrical stunning and exsanguination decrease the extracellular volume in the broiler brain as studied with brain impendance recordings.

Electrical stunning in the process of slaughtering poultry is used to induce unconsciousness and immobilize the animal for easier processing. Unconsciousness is a function of brain damage. Brain damage has been studied with brain impedance recordings under ischemic conditions. This experiment studies brain impedance as a response to a general epileptiform insult caused by electrical stunning and ischemia caused by exsanguination. Brain impedance was recorded in 10 broiler chickens for each of three killing methods: whole body electrical stunning, which induces cardiac arrest; head only electrical stunning followed by exsanguination; and exsanguination without stunning. Brain impedance was converted into relative extracellular volume (ECV) values. Results showed that, immediately after electrical stunning, the ECV decreased 5.5% from base ECV. With exsanguination only, the ECV decreased from base ECV only after 4 min after neck cutting. The ECV decrease after 10 min did not differ between treatments. With a time of 228 s to reach one-half of the ECV decrease found at 10 min, electrical stunning resulted in a much faster change in ECV than exsanguination only (373 s). Within the head only stunning group, six animals showed a response similar to that found with whole body stunning; the other four animals responded similarly to the animals that were exsanguinated only. It was concluded that brain impedance recordings used with electrical stunning reflect brain damage. This damage was both epileptic and ischemic in nature. Whole body stunning induced immediate brain damage, suggesting that an adequate stun was delivered. The dual response found with head only stunning might indicate that this stunning method does not always produce an adequate stun.

Abattoirs↗
PubMed1999

The effects of captive bolt and electrical stunning, and restraining methods on broiler meat quality.

The effects of captive bolt stunning using air pressure, compared to electrical water bath stunning, on broiler carcass and meat quality were evaluated. The birds were shackled or placed in a cone. Two trials were conducted using a total of 160 female broilers. The four stunning-restraining treatments were whole-body electrical stunning (10 s, 110 mA, 300 Hz) in a water bath or air pressure stunning (0.5 s, 2 atm) while broilers were shackled by their feet or placed in a cone. Air pressure stunning caused a higher (P < 0.01) degree of convulsions and a lower (P < 0.01) degree of blood loss than electrical stunning, and reduced the prevalence of broken clavicles (P < 0.05) and coracoids (P < 0.01). Blood loss of shackled broilers was slightly higher (P < 0.05) than those restrained in a cone. Air pressure stunning resulted in significantly (P < 0.01) lower pH values and hemorrhaging in filets and thigh muscles than electrical stunning. The incidence of thigh muscle hemorrhaging was significantly (P < 0.01) reduced when broilers were restrained in a cone compared to being shackled. The stunning and restraining treatments did not result in differences in cooking losses. The filets from shackled birds were judged more tender than the filets from cone-restrained birds. With respect to the effect of stunning method, the filets of air pressure stunned birds was judged more tender than the meat from electrically stunned birds. Captive bolt stunning using air pressure has benefits over electrical stunning; however, a suitable stunning and restraining device remains to be developed.

Abattoirs↗
PubMed1999

The effect of shot biopsy on behavior, salivary cortisol, and heart rate in slaughter pigs.

This paper describes behavioral and physiological responses of pigs to shot biopsy, an experimental method used to study muscle tissue processes or to predict meat quality. One biopsy sample from the longissimus muscle was obtained from 23-wk-old gilts (n = 10) using a cannula connected to a captive bolt. Ten other gilts were used as a control and received a sham shot. One week later, a second biopsy was taken from the same gilts. Behavioral and salivary cortisol responses to both biopsies were similar (P > .10). Pigs flinched in response to the biopsies. Salivary cortisol concentrations were increased (P < .05) 15 min after the biopsy as compared with pretreatment levels, but absolute levels were not different (P > .10) from the control group. In both biopsy and control groups, heart rate increased (P < .001) in response to the presence of the technician. In response to the first biopsy, heart rate increased (P < .01) as compared with the rate during the 5-s period before the biopsy, but heart rate did not increase in response to the second biopsy. The biopsy pigs showed a decrease (P < .05) in initiating contact with the technician in the second test. We conclude that shot biopsy had a significant acute effect on behavior and heart rate. Therefore, the usefulness of this technique in studies in which the behavioral and heart rate responses are measured is limited.

Animals↗
PubMed1998

Effects of simulated lairage conditions on the physiology and behaviour of pigs.

The responses of pigs to being driven and mixed together in lairage were investigated. Five groups of six and five groups of seven 70 kg pigs were transported for 40 minutes on a lorry and then subjected to one of the following treatments: two groups were driven down a passage; four groups (A to D) were mixed together for one hour (A and B together, and C and D together); and, four groups were driven down the passage and then mixed ('combined treatment'). The pigs' behaviour was recorded, skin damage was scored and saliva samples were taken for analysis of cortisol. The initial journey increased the pigs' salivary concentration of cortisol. Their behaviour while being driven was not correlated with the concentrations of cortisol after they were driven and cortisol concentrations did not increase relative to post-transport levels. The frequency and duration of fighting when they were mixed were positively correlated with their level of aggression in the home pen and with the increase in concentrations of cortisol when they were mixed. One hour after they had been mixed, the concentrations of cortisol had decreased relative to post-transport levels. After the combined treatment, the correlations observed for the mixing treatment were absent, and the concentrations of cortisol increased relative to post-transport levels. Skin damage was greatest after the groups of pigs were mixed. The responses observed indicate that the combined effects of driving and mixing, which are very common in lairage, were greater than the effects of driving or mixing alone.

Aggression↗
PubMed1998

Effects of strawbedding on physiological responses to stressors and behavior in growing pigs.

To study the effects of environmental enrichment on physiological responses to stressors and behavior in growing pigs, pigs were housed in either a poor environment (standard farrowing pens followed by standard rearing and fattening pens) or in an enriched environment (larger farrowing pens followed by larger rearing and fattening pens, provision of straw). Body temperature, heart rate and salivary cortisol were measured during baseline conditions and in response to relocation, isolation and restraint. Pigs housed in the poor environment performed more manipulative social behavior directed to penmates than pigs housed in the enriched environment. Physiological responses to the stressors were the same for enriched- and poor-housed pigs. Surprisingly, enriched-housed pigs had significantly higher baseline salivary cortisol concentrations, especially at 14 and 17 weeks of age. Moreover, enriched housed pigs had a lower baseline body temperature at 17 weeks of age. Thus, provision of straw has an effect on behavior, baseline HPA-axis activity and baseline body temperature in growing pigs.

Adrenal Glands↗
PubMed1998

Responses of slaughter pigs to transport and lairage sounds.

The behavioral and physiological responses of pigs to transport and subsequent exposure to slaughterhouse sounds were examined. Forty-one groups of four slaughter pigs were separately loaded onto a lorry and transported for 25 min. Another 43 groups were loaded onto the lorry which then remained stationary for 25 min. Following unloading pigs were moved to a race with a length of 15 m and a width of 1.5 m. Either one of the following sounds was played at 85 dB(A) for 10 min: Pigs in front of the restrainer, Machines in lairage, White Noise, or Control (no sound). Pigs exposed to the Machines and White Noise treatment spent significantly more time close to their group-mates compared with Control pigs, with pigs subjected to the Pig sound being intermediate. Transported pigs spent less time exploring the race and were less active than pigs from the stationary lorry. Heart rate was higher during transport than during the stationary period. In contrast, during unloading, the sound exposure period and the post-sound period, heart rate was lower in the transported groups. Heart rate did not significantly differ between sound treatments. Salivary cortisol concentrations were significantly higher after transport than after the stationary period and remained higher for transported pigs after the sound exposure period. Cortisol levels did not differ significantly between sound treatments. It is tentatively suggested that social support from conspecifics may protect pigs from potentially adverse effects of exposure to lairage sounds.

Abattoirs↗
PubMed1998

Impedance recordings to determine change in extracellular volume in the brain following cardiac arrest in broiler chickens.

The present study describes a method to determine the onset and development of brain damage in broiler chickens. Exsanguination disrupts the brain metabolism and causes the brain to become ischemic. Energy-requiring systems in the cell membrane fail, which results in an ionic shift over the membrane, accompanied by a water influx into the cell. This cellular edema decreases the extracellular volume of brain tissue. In mammals, this brain damage has been measured by recording brain impedance. We adapted this approach for use with poultry. Five to six-week-old commercial broilers were equipped with impedance recording electrodes in the striatum area of the brain. Cardiac arrest was induced by means of an intravenous injection of MgCl2 and brain impedance was recorded for 30 min. The resulting curves showed a high similarity to those obtained in rats. No effects of 12 h antemortem feed deprivation on the size and rate of change in brain impedance could be found. Both in anesthetized and conscious birds, a change in brain impedance was found. We conclude that brain impedance can be used to determine the development of ischemic brain damage in broiler chickens.

Animals↗
PubMed1998

Effects of regular moving and handling on the behavioral and physiological responses of pigs to preslaughter treatment and consequences for subsequent meat quality.

The effects of regular moving and handling during the finishing period on behavioral and physiological responses of pigs during preslaughter treatment and consequences for meat quality were studied. From the age of 10 wk onward, 144 pigs were housed in groups of four (two gilts and two castrates) and subjected to one of the following treatments. The Environment treatment allowed pigs to move freely for 8 min outside their home pen. Then the pigs were transported in a box for 2 min, and after which they were returned to their home pen. In the Handling treatment, an experimenter remained for 3 min in the pen, and whenever a pig made contact, it was gently stroked. The experimenter then walked for an additional 1 min, without attempting to pat or stroke any pigs but subsequently held each pig in a tight grip for about 5 s. This entire procedure was then repeated. A Control treatment was also included, in which the pigs were subjected to no treatment. The Environment and Handling treatments were applied twice a week at the age of 15, 17, 19, 21, and 23 wk. At 25 wk of age, pigs were transported to the abattoir. They were held unmixed in the truck and in lairage and were manually stunned. The stockmen needed significantly less time to move Environment pigs out of their pen and into the transport box. There were no differences between treatments in salivary cortisol concentrations before or after transport. Environment and Handling pigs had paler meat than Control pigs. Glycogen content at 1 h after death and water-holding capacity were lower in Environment pigs than in Control pigs, but this did not lead to a higher incidence of PSE meat. We conclude that the pigs that had experience with leaving their home pen and some of the transport conditions were much easier to handle at loading. Pigs that are easier to move are less likely to be subjected to rough handling, which implies improved welfare, and the workload for personnel at the time of marketing is reduced. Differences in meat quality due to treatment were slight.

Abattoirs↗
PubMed1995

Effects of injecting electronic transponders into the auricle of pigs.

Electronic transponders (3 x 18 mm) were injected into the base of the auricle of 69 10-day-old pigs, 111 four-week-old pigs and 24 six-month-old pigs, to examine the procedure of injection in the auricle, the tissue reaction and the ease of removal from the carcase. The injection was difficult in the 10-day-old pigs, but was easier at four weeks. One of the 204 transponders were lost and five of them appeared to be broken. Only one gilt showed some exudate around the transponder. The transponders could easily be removed when the pigs were slaughtered by cutting off the ear. The position of the transponder was significantly (P < 0.05) more ventral in the animals injected at 10 days old than in those injected at four weeks. The mean thickness of the connective tissue capsule around the transponders increased at first (P < 0.1) and then decreased when they were injected into 10-day-old pigs but decreased (P < 0.1) from shortly after injection in the pigs injected at four weeks old. After five months, the capsule in the animals injected at 10 days old was on average significantly (P < 0.01) thinner than in those injected at four weeks.

Animal Identification Systems↗
PubMed1995

Electronic identification with injectable transponders in pig production: results of a field trail on commercial farms and slaughterhouses concerning injectability and retrievability.

A nationwide electronic system for the identification of all pigs is a means to achieve a tighter control of livestock and meat in the Netherlands. In order to examine the use of electronic identification transponders, two field trails were performed. Transponders supplied by three separate companies were tested on pigs on commercial farms. In phase 1, each device was examined on separate farms and in phase 2, the three devices were tested on each farm. A total of 3,436 and 5,947 transponders from the different suppliers were injected in the base of the ear at weaning in phase 1 and 2 on seven and five farms, respectively. The following aspects were examined: technical labour for injection and reading, readability of the transponders, impact on tissues at the injection site, and retrieval of the transponder after slaughter. After instruction the farmer was well able to inject a transponder in a restrained piglet. The results show that in phases 1 and 2 1.6% to 7.3% of the transponders were unreadable at retrieval in the slaughter line, which is significantly (p < 0.05) higher than the required maximum loss of 1%. The 1.6% failure rate in phase 1 involved transponders from a single supplier. Loss of identification was associated with rejection after injection, expulsion during inflammation and technical failure. Three weeks after injection on average 0.6% of the piglets had an observable inflammation and at the time of retrieval pus was found around, on average, 1.2% of the transponders. An average of between 37% and 88% of the transponders were retrieved in the slaughter line from the base of the ear in phases 1 and 2. The other transponders were retrieved medial or caudal to this position. This positional variation meant that it was not consistently possible to remove the transponder from the carcass within the required 4 second time period. It was concluded that the systems should be improved before recommending their introduction on a large scale, because the variation in readability and location is too high.

Abattoirs↗
PubMed1994

[Stunning of slaughtering animals on the farm].

Recent changes in the Inspection Regulations have made it possible for practising veterinarians to stun and bleed animals on the farm. The Health and Welfare Law stipulates, amongst other things, that it is not permissible to put the welfare of the animal to disadvantage. Mechanical methods are the most suitable for use on farms, and of these methods the humane (cattle) killer is clearly to be preferred. The humane killer should be placed frontally, where the imaginary lines between the eyes and ears cross, or occipitally above the brain. A firearms license is needed. As many practising veterinarians are not experienced in the stunning and bleeding of animals, it is advised that these actions be left to emergency butchers.

Animals↗