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1.
This study investigated the effects of various stunning methods on the quality of French 'foie gras' in ducks and geese. The ducks (n = 30 per group) were stunned with one of the following techniques: electrical stunning in a water bath (50 Hz AC, 130 mA, 4 s), head-only electrical stunning (50 Hz AC, 600 mA, 4 s), mechanical stunning (captive bolt) and controlled atmosphere stunning (CAS: phase 1, CO2 (40%)-O2 (30%)-N2 (30%), for 2 min followed by phase 2, CO2 >85% in air, for 2 min). The same methods (except head-only stunning which was not applied) were used in geese (n = 40 per group). The weight of the liver at slaughter was not affected by the stunning techniques, neither was its colour (L*, a*, b* coordinates), despite the differences in bleeding rate between the stunning treatments. The loss of fat during the cooking of canned fatty liver did not depend upon stunning treatment. Some appearance defects of raw fatty livers were significantly affected by the treatment: mechanical and head-only stunning induced higher incidence of petechial haemorrhages in duck liver, whereas in geese, incidence of superficial haemorrhages was significantly higher after CAS and water-bath stunning. The calculation of an overall score based on the incidence and severity of the different appearance defects observed in the present experiment showed that CAS was associated with the least favourable position in ducks as well as in geese, compared to the other treatments. The commercial grading of ducks and geese fatty livers, carried out by an expert from the industry, clearly showed the detrimental effect of CAS on the commercial value of raw livers. CAS, under the conditions applied in the present work cannot be recommended, because of its drastic effect on liver quality. The underlying mechanisms deserve further investigations.  相似文献   

2.
The aim of this study was to assess the effect of exposure to the gas mixtures of 70% nitrogen (N2) and 30% carbon dioxide (CO2; 70N30C), 80% N2 and 20% CO2 (80N20C) and 85% N2 and 15% CO2 (85N15C) on aversion, stunning effectiveness and carcass, as well as meat quality in pigs, and to compare them with the commercial stunning of 90% CO2 (90C). A total of 68 female pigs were divided into four groups and stunned with one of the gas mixtures. During the exposure to the gas, behavioural variables (retreat attempts, escape attempts, gasping, loss of balance, muscular excitation and vocalizations) were recorded, and at the end of the stunning, corneal reflex and rhythmic breathing were assessed. After slaughter, meat quality parameters such as pH at 45 min post mortem (pH45) and at 24 h post mortem (pHu), electrical conductivity, drip loss and colour, in the Longissimus thoracis (LT) and Semimembranosus (SM) muscles were measured, and the presence of ecchymosis on the hams was noted. The PROC MIXED and the PROC GENMOD of SAS® were used to analyse the parametric and binomial variables, respectively. The ‘gas mixture’ was always considered a fixed effect and the ‘live weight’ as a covariate. To assess the correlation between meat quality and behaviour measures, PROC CORR was used. Pigs exposed to 90C showed a higher percentage of escape attempts and gasping, a lower percentage of vocalization and shorter muscular excitation phase than pigs exposed to the other N2 and CO2 mixtures (P < 0.05). After stunning, no pig exposed to 90C showed corneal reflex or rhythmic breathing, whereas 85% and 92% of the animals exposed to N2 and CO2 mixtures showed corneal reflex and rhythmic breathing, respectively. Animals stunned with 80N20C and 85N15C had a lower pH45 (P < 0.01) than animals exposed to 90C. Electrical conductivity in the SM muscle was lower (P < 0.001) in 90C and 70N30C pigs than in 80N20C and 85N15C pigs, whereas in LT, it was lower (P < 0.05) in 90C pigs than in 85N15C. As the CO2 concentration of the gas mixture was decreased, the prevalence of exudative pork increased. Twenty-five percent of animals exposed to N2 and CO2 mixtures (n = 68) had ecchymosis in their carcasses, whereas no animal stunned with 90C had ecchymosis. In conclusion, although N2 and CO2 stunning exhibit fewer signs of aversion than 90C, their induction time to unconsciousness is longer, and this may negatively affect meat and carcass quality.  相似文献   

3.
Guinea pigs (Cavia porcelus) are an important source of nonhuman animal protein in the Andean region of South America. Specific guidelines regarding the welfare of guinea pigs before and during slaughter have yet to be developed. This study critically assessed the humaneness of 4 different stunning/slaughter methods for guinea pigs: cervical neck dislocation (n = 60), electrical head-only stunning (n = 83), carbon dioxide (CO2) stunning (n = 21), and penetrating captive bolt (n = 10). Following cervical neck dislocation, 97% of guinea pigs had at least 1 behavioral or cranial/spinal response. Six percent of guinea pigs were classified as mis-stunned after electrical stunning, and 1% were classified as mis-stunned after captive bolt. Increased respiratory effort was observed during CO2 stunning. Apart from this finding, there were no other obvious behavioral responses that could be associated with suffering. Of the methods assessed, captive bolt was deemed the most humane, effective, and practical method of stunning guinea pigs. Cervical neck dislocation should not be recommended as a slaughter method for guinea pigs.  相似文献   

4.
Contrary to chicken and livestock mammals, duck genome has not been explored much. Nowadays a relatively small number of reports on molecular variability and mapping of loci in Peking ducks has been published. Therefore, the objective of this study was to detect single loci affecting body weight, carcass and meat traits in Peking ducks (Anas platyrhynchos). The study was based on an F2 cross between two parental lines A-55 and GL-30. Phenotypes of 387 birds from generation F2 including carcass and meat quality traits were collected. Linkage map, of the linkage group CAU1, consisting of 29 microsatellite markers was constructed. One highly significant (p?p?相似文献   

5.
The main objective of this study was to investigate the influence of different types of slaughtering on the variations of pH and temperature. Ninety entire male beef cattle, belonging to the Charolais breed, were distributed in three groups based on method of slaughtering. A total of 30 subjects (group K) were slaughtered without stunning, according to the Koscher rite; thirty bovines (group T) were stunned with a captive bolt gun, following the common slaughtering reported by Council Regulation (EC) 1099/2009; other thirty animals (group H) were slaughtered without stunning, based on Halal procedures. The temperature and pH values of carcasses were determined at 3, 6 and 24 h post-mortem, respectively. At 24 h post-mortem of the 30 carcasses evaluated for each group, muscle temperature decreased in all three types of slaughtering. In particular, the average temperature was 4.0, 4.9 and 3.0 °C for traditional, Halal and Koscher slaughtering, respectively. Moreover, at the same time step (24 h post-mortem), muscle pH decreased showing values equal to 5.72, 5.83, 5.81 for traditional, Halal and Koscher slaughtering, respectively. The findings of the present study may be useful to highlight the influence of slaughtering method on pH and, more generally, on meat quality. Additionally, our results show that, in slaughtering carried out without prior stunning, the carcass could be more susceptible to alterations because of the high pH values.  相似文献   

6.
Huang Y  Haley CS  Wu F  Hu S  Hao J  Wu C  Li N 《Animal genetics》2007,38(2):114-119
Quantitative trait loci (QTL) for carcass and meat quality traits were detected in a sample of 224 progeny from four males in line VI and 12 females in line V of Beijing ducks. These lines were selected for high body weight at 42 days of age (line VI) or high egg production at 360 days of age (line V). Traits were weights of the carcass, head, neck, shanks, wings, legs, thighs, breast, heart, liver, crop, gizzard, abdominal fat (AFW) and skin fat, as well as fat thickness in the tail, and pH value, shear force, drip loss (DL) (%) and cooking loss (CL) (%) of the breast. Using a half-sib analysis with a multiple QTL model, linkage between the carcass and meat quality traits and 95 microsatellite markers was investigated. Eight genome-wide significant QTL for weight of crop, skin fat, liver, neck, shanks, wings, DL were detected on linkage groups CAU4 and CAU6. One genome-wide suggestive QTL and one chromosome-wide significant QTL for weight of breast were found on CAU1 and CAU4 respectively. Fifteen chromosome-wide suggestive QTL influencing weight of AFW, breast, crop, heart, carcass, thighs, liver, shanks, gizzard, fat thickness in tail, DL (%) and CL (%) were mapped on CAU2, CAU4, CAU5, CAU6, CAU7, CAU10 and CAU13. In addition, two linked QTL for weight of liver and DL (%) were located on CAU2 and CAU7 respectively. The detection of QTL in ducks is a step towards identification of genes influencing these traits and their use for genetic improvement in this species.  相似文献   

7.

Background

Tail biting is a common welfare problem in pig production and in addition to being a sign of underlying welfare problems, tail biting reduces welfare in itself. The aim of this study was to evaluate the effects of tail biting on different pre and post mortem indicators of stress in slaughter pigs and on carcass and meat characteristics. A total of 12 tail bitten (TB) and 13 control (C) pigs from a farm with a long-term tail biting problem were selected for salivary cortisol analyses before and after transport to the slaughterhouse. After stunning, samples were taken for the analysis of serum cortisol, blood lactate, intestinal heat shock protein 70 (HSP70), and meat quality characteristics. In addition, body temperature immediately after and muscle temperature 35 min after stunning were measured, as well as lean meat percentage and carcass weight.

Results

TB pigs showed a lower cortisol response to the transport-induced stress than C pigs and also had a lower serum cortisol concentration after stunning. HSP70 content in the small intestine was higher in the TB pigs than in C pigs. TB pigs had a considerably lower carcass weight therefore produced a lower total amount of lean meat per carcass than C pigs.

Conclusions

This study suggests that prolonged or repeated stress in the form of tail biting causes a blunted stress response, possibly a sign of hypocortisolism. In addition, it underlines the importance of reducing tail biting, both from an animal welfare and an economic point-of-view.
  相似文献   

8.
To determine whether an interaction between central respiratory and locomotor networks may be involved in the observed coordination of wingbeat and respiratory rhythms during free flight in birds, we examined the relationship between wingbeat and respiratory activity in decerebrate Canada geese and Pekin ducks before and after paralysis. Locomotor activity was induced through electrical stimulation of brain stem locomotor regions. Respiratory frequency (fv) was monitored via pneumotachography and intercostal electromyogram recordings before paralysis and via intercostal and cranial nerve IX electroneurogram recordings after paralysis. Wingbeat frequency (fW) was monitored using pectoralis major electromyogram recordings before, and electroneurogram recordings after, paralysis. Respiratory and cardiovascular responses of decerebrate birds during active (nonparalyzed) and "fictive" (paralyzed) wing activity were qualitatively similar to those of a variety of vertebrate species to exercise. As seen during free flight, wingbeat and respiratory rhythms were always coordinated during electrically induced wing activity. Before paralysis during active wing flapping, coupling ratios (fW/fv) of 1:1, 2:1, 3:1, and 4:1 (wingbeats per breath) were observed. After paralysis, fW and fv remained coupled; however, 1:1 coordination predominated. All animals tested (n = 9) showed 1:1 coordination. Two animals also showed brief periods of 2:1 coupling. It is clear that locomotor and respiratory networks interact on a central level to produce a synchronized output. The observation that the coordination between fW and fv differs in paralyzed and nonparalyzed birds suggests that peripheral feedback is involved in the modulation of a centrally derived coordination.  相似文献   

9.
We tested the hypothesis that atrial natriuretic peptide (ANP) would decrease both the effects of myocardial stunning and oxygen consumption in rabbit hearts. In two groups of anesthetized open-chest rabbits, myocardial stunning was produced by two 15 min occlusions of the left anterior descending (LAD) artery separated by 15 min of reperfusion. Either ANP (0.2 mg) or vehicle (lactated Ringers) was then injected into the affected area of the left ventricle. In a third group, ANP was injected into the LAD region of non-stunned rabbits. Hemodynamic (heart rate, aortic and left ventricular pressures) and functional (wall thickening (WT), delay of onset of WT, and rate of WT) parameters were measured. Coronary blood flow (microspheres) and O2 extraction (microspectrophotometry) were used to determine myocardial O2 consumption. Stunning was demonstrated by an increase in the time delay to contraction and depressed WT. In the control group, baseline delay to contraction was 25+/-7 ms, and this increased to 84+/-16 following stunning and vehicle administration. In the ANP group, baseline delay was 20+/-6 at baseline and after stunning and ANP administration it was 30+/-7. Wall thickening decreased by approximately 30% with stunning and vehicle but only 8% in the ANP treated hearts. Stunning did not affect regional O2 consumption (6.0+/-1.1 stunned vs. 7.4+/-1.2 mlO2/min/100g non-stunned). ANP administration did not affect O2 consumption (7.3+/-1.7 stunned vs. 6.4+/-1.0 non-stunned). We therefore concluded that ANP administration reversed the effects of stunning without alteration in local O2 consumption in stunned myocardium.  相似文献   

10.
Studies that address fish welfare before slaughter have concluded that many of the traditional systems used to stun fish including CO2 narcosis are unacceptable as they cause avoidable stress before death. One system recommended as a better alternative is electrical stunning, however, the welfare aspects of this method are not yet fully understood. To assess welfare in aquaculture both behavioural and physiological measurements have been used, but few studies have examined the relationship between these variables. In an on-site study aversive behaviours and several physiological stress indicators, including plasma levels of cortisol and ions as well as blood physiological variables, were compared in Arctic char (Salvelinus alpinus) stunned with CO2 or electricity. Exposure to water saturated with CO2 triggered aversive struggling and escape responses for several minutes before immobilization, whereas in fish exposed to an electric current immobilization was close to instant. On average, it took 5 min for the fish to recover from electrical stunning, whereas fish stunned with CO2 did not recover. Despite this, the electrically stunned fish had more than double the plasma levels of cortisol compared with fish stunned with CO2. This result is surprising considering that the behavioural reactions were much more pronounced following CO2 exposure. These contradictory results are discussed with regard to animal welfare and stress physiological responses. The present results emphasise the importance of using an integrative and interdisciplinary approach and to include both behavioural and physiological stress indicators in order to make accurate welfare assessments of fish in aquaculture.  相似文献   

11.
This study was conducted to evaluate the effects of feeding aerobically processed and vacuum-dried food waste-broiler litter and bakery by-product mixture to finishing pigs on performance, carcass characteristics, meat quality and taste panel test. A corn-soy diet (Control) was replaced with food waste mixture (FWM) at dietary levels of 25% (25% FWM) and 50% (50% FWM) on a dry matter (DM) basis. Diets were fed to a total of 45 pigs (mean body weight 69.4kg) during the eight wk of finishing period. After slaughtering, longissmus muscle at 24h postmortem was used for meat quality analysis. Restaurant food waste was high in protein (22.0%) and fat (23.9%). Supplementing a corn-soy diet with FWM increased (P<0.05) feed DM intake, did not alter (P>0.05) average daily gain, decreased (P<0.05) feed efficiency especially for 50% FWM treatment, and substantially reduced (P<0.05) feed cost, compared with feeding a corn-soy diet only. Feeding FWM up to 50% did not affect (P>0.05) carcass characteristics (carcass weight, dressing percentage, backfat thickness and carcass grade), meat fatty acid composition, meat quality (marbling score, pH, water holding capacity, drip loss, L*, a*, b* values, Warner-Bratzler shear force, cooking loss), and taste panel test (flavor, taste, tenderness, juiciness, and overall acceptance) compared with feeding a corn-soy diet. However, meat color was paler (P<0.05) for 50% FWM fed animals than a corn-soy diet fed animals. Meat color was the only limiting factor when FWM was fed to finishing pigs. In conclusion, aerobically processed and vacuum-dried food waste-broiler litter and bakery by-product mixture was similar to a corn-soy diet in feed value for finishing pigs.  相似文献   

12.
AIMS: The aim of this study was to use a marked strain of Pseudomonas fluorescens to model the spread of central nervous system (CNS) tissue in cattle following captive bolt stunning. METHODS AND RESULTS: The marked organism was introduced by injection through the captive bolt aperture immediately after stunning and was subsequently detected in a wide range of derived tissues, including blood, organs, and the musculature of the entire forequarters of test animals. This was dependent on the use of high concentrations of the organism that were recovered sufficiently and rapidly to minimize the bactericidal properties of the circulatory system. These results suggest that a marked organism could potentially be used to model the effects of captive bolt stunning on the dissemination of CNS tissue from the brain. CONCLUSIONS: These results indicate that current commercial methods of captive bolt stunning may induce widespread and significant mobilization of CNS tissue within beef carcasses. This may lead to the widespread dissemination of such materials within meat destined for human consumption. SIGNIFICANCE AND IMPACT OF THE STUDY: In the absence of rapid, simple and sufficiently sensitive methods for the direct detection of prion in commercially slaughtered animals, marked organisms can provide useful models in studies of the dissemination kinetics of prion disease in captive bolt stunned animals.  相似文献   

13.
To investigate cardiac stunning, we recorded intracellular [Ca(2+)], contractions, and electrical activity in isolated guinea pig ventricular myocytes exposed to simulated ischemia and reperfusion. After equilibration, ischemia was simulated by exposing myocytes to hypoxia, acidosis, hyperkalemia, hypercapnia, lactate accumulation, and substrate deprivation for 30 min at 37 degrees C. Reperfusion was simulated by exposure to Tyrode solution. Field-stimulated myocytes exhibited stunning upon reperfusion. By 10 min of reperfusion, contraction amplitude decreased to 43.0 +/- 5.5% of preischemic values (n = 15, P < 0.05), although action potential configuration and sarcoplasmic reticulum Ca(2+) stores, assessed with caffeine, were normal. Diastolic [Ca(2+)] and Ca(2+) transients (fura 2) were also normal in stunned myocytes. In voltage-clamped cells, peak L-type Ca(2+) current was reduced to 47.4 +/- 4.5% of preischemic values at 10 min of reperfusion (n = 21, P < 0.05). Contractions elicited by Ca(2+)-induced Ca(2+) release and the voltage-sensitive release mechanism were both depressed in reperfusion. Our observations suggest that stunning is associated with reduced L-type Ca(2+) current but that alterations in Ca(2+) homeostasis and release are not directly responsible for stunning.  相似文献   

14.
Spur-winged geese at Barberspan, an agricultural area in South Africa, had an average carcass composition of 64% water, 22% protein, 6% lipid, 6% minerals and 2% carbohydrate with an energy content of 21.6 kJ g-1 DW. There were significant changes during the year in protein and lipid levels; they were lowest during the annual flightless wing moult. Protein and lipid levels also declined during breeding but this event had less effect on body reserves than moulting. The relationships between various body measurements and mineral content of the carcass (as an estimate of skeletal weight) were examined.  相似文献   

15.
Abattoirs commonly use penetrating captive bolt pistols to stun cattle. Humane slaughter requires that an animal immediately becomes unconscious and does not regain consciousness. In this review we consider the concepts of concussion, unconsciousness, and return to consciousness. We conclude that an animal effectively stunned with a penetrating captive bolt pistol, as indicated by the presence of certain signs and the absence of others, has little possibility of brain function returning. Appropriate monitoring at all stages between stunning and sticking would ensure immediate detection and restunning on those few occasions when brain function was returning. When a captive bolt irreversibly stuns animals, sticking has no role in terms of animal welfare; its only function is to relieve the carcass of blood. With effective initial stunning and subsequent monitoring, specifying a stun-to-stick interval appears unnecessary. Abattoir surveys have indicated that it is possible to approximate, or even actually obtain, 100% successful stunning from a single shot. Furthermore, low prevalence of recovery follows. Thus, penetrating captive bolt stunning can form part of a process for the humane slaughter of cattle. This article outlines an approach to implementing standard operating procedures for checking the effectiveness of captive bolt stunning.  相似文献   

16.
Abattoirs commonly use penetrating captive bolt pistols to stun cattle. Humane slaughter requires that an animal immediately becomes unconscious and does not regain consciousness. In this review we consider the concepts of concussion, unconsciousness, and return to consciousness. We conclude that an animal effectively stunned with a penetrating captive bolt pistol, as indicated by the presence of certain signs and the absence of others, has little possibility of brain function returning. Appropriate monitoring at all stages between stunning and sticking would ensure immediate detection and restunning on those few occasions when brain function was returning. When a captive bolt irreversibly stuns animals, sticking has no role in terms of animal welfare; its only function is to relieve the carcass of blood. With effective initial stunning and subsequent monitoring, specifying a stun-to-stick interval appears unnecessary. Abattoir surveys have indicated that it is possible to approximate, or even actually obtain, 100% successful stunning from a single shot. Furthermore, low prevalence of recovery follows. Thus, penetrating captive bolt stunning can form part of a process for the humane slaughter of cattle. This article outlines an approach to implementing standard operating procedures for checking the effectiveness of captive bolt stunning.  相似文献   

17.
Wen  Min  Wu  Bing  Zhao  Hua  Liu  Guangmang  Chen  Xiaoling  Tian  Gang  Cai  Jingyi  Jia  Gang 《Biological trace element research》2019,190(1):187-196
Biological Trace Element Research - This study investigated the effects of dietary zinc on carcass traits, meat quality, antioxidant capacity, and tissue zinc accumulation of Pekin ducks. A total...  相似文献   

18.
The experiment comprised of 50 chickens, 40 ducks and 30 geese fed a diet containing 40% barley. Birds were kept in metabolic cages from 1 to 42 days of age. A balance trial was carried out during the last week of the bird's life and the apparent digestibility of nutrients was determined. At 21 and 42 days of age 12 animals per species were killed. The absolute length of intestines followed the live weight (LW) of the animals. In relation to metabolic LW (kg(0.67)), the total length was significantly higher in chickens and geese than in ducks at 21 days of age, but identical in the three species at 42 days of age. The absolute and relative weights of intestines were smaller in ducks than in chickens and geese both at 21 and 42 days of age. Dietary fibre was digested better by chickens than by ducks and geese (P<0.01). Ileal digestibility of total amino acids amounted to 76% in chickens, 69% in ducks (P>0.05) and only 56% in geese (P<0.01) with relatively low digestibility of methionine (70, 44 and 52%) and lysine (72, 57 and 41%), respectively. The overall tract-faecal digestibility of total amino acids was evaluated on the level of 86% for all three species and indicates a substantial hind gut synthesis of amino acids.  相似文献   

19.
1. These studies were carried out to compare certain hepatic microsomal drug-metabolizing enzymes of quail, ducks, geese, chickens, turkeys and rats. 2. Comparison of relative liver weights of the species indicated that the rats had the largest weight followed by turkeys, ducks, geese, chickens and quail. 3. Rats ranked highest in hepatic cytochrome P-450 content followed in decreasing order by turkeys, geese, chickens, ducks and quail. 4. Microsomal benzphetamine N-demethylase activity was significantly higher in geese and turkeys than that for the rest of the species. 5. Geese, chickens and turkeys showed similar aniline hydroxylase activity, while it was markedly lower in quail and ducks with rats being intermediate.  相似文献   

20.
Quantitative trait loci (QTL) affecting carcass and meat quality located on SSC2 were identified using variance component methods. A large number of traits involved in meat and carcass quality was detected in a commercial crossbred population: 1855 pigs sired by 17 boars from a synthetic line, which where homozygous (A/A) for IGF2. Using combined linkage and linkage disequilibrium mapping (LDLA), several QTL significantly affecting loin muscle mass, ham weight and ham muscles (outer ham and knuckle ham) and meat quality traits, such as Minolta-L* and -b*, ultimate pH and Japanese colour score were detected. These results agreed well with previous QTL-studies involving SSC2. Since our study is carried out on crossbreds, different QTL may be segregating in the parental lines. To address this question, we compared models with a single QTL-variance component with models allowing for separate sire and dam QTL-variance components. The same QTL were identified using a single QTL variance component model compared to a model allowing for separate variances with minor differences with respect to QTL location. However, the variance component method made it possible to detect QTL segregating in the paternal line (e.g. HAMB), the maternal lines (e.g. Ham) or in both (e.g. pHu). Combining association and linkage information among haplotypes improved slightly the significance of the QTL compared to an analysis using linkage information only.  相似文献   

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