Slaughter Method Research Articles

Effect of harvesting stress and slaughter conditions on selected flesh quality criteria of gilthead seabream ( Sparus aurata)

The aim of this study was to assess the independent effects of harvesting stress and slaughter method on seabream flesh quality. Two groups of 32 gilthead seabream (mean body weight: 536 ± 96 g) were subjected to different pre-slaughter harvesting stress: profound anesthesia (PA, low stress condition) and net crowding (NC, high stress condition). Subsequently, fish from both harvesting stress conditions were slaughtered using either ice–salt water slurry (IW), to simulate commercial practices, or a lethal dose of anesthesia (LA), to isolate the effect of the pre-slaughter treatments. Rigor mortis was measured during the first 72 h after death, and muscle from the dorsal area was collected at regular intervals (0, 2, 6 and 48 h after death) during this period, for subsequent biochemical analysis of pH, TBARS, sulfated glycosaminoglycans and hydroxyproline content. Texture in raw and cooked fillets was measured instrumentally, using an Instron texture analyzer. The onset of rigor mortis was earliest for the NC–IW treatment, reaching highest values 2 h after death, while fish from the PA–IW treatment attained highest rigor scores 21 h after death. Resolution of rigor mortis started 3 and 32 h after death in fish subjected to NC and PA, respectively. Both harvesting stress and slaughter method had a significant effect ( P < 0.05) on muscle pH, with highest values found in fish subjected to PA conditions, and in those slaughtered by lethal anesthesia. Muscle TBARS were significantly affected by harvesting stress. Collagen and sulfated glycosaminoglycan content of the samples decreased markedly through storage time, but were not significantly affected by harvesting stress conditions or slaughter method. In fish slaughtered in ice–salt water slurry, fillet hardness ranged between 5.0 ± 2.1 and 5.7 ± 1.8 N in raw fillets, and between 4.9 ± 0.9 and 5.6 ± 0.9 N in cooked fillets, but no significant differences among treatments were found. The use of zero withdrawal anesthetic improved muscle pH and delayed rigor mortis, although harvesting and slaughter stress had no major effect on muscle structure of gilthead seabream.

Industrial dry electro-stunning followed by chilling and decapitation as a slaughter method in Claresse ® ( Heteroclarias sp.) and African catfish ( Clarias gariepinus)

This study evaluated the industrial application of dry electro-stunning for Claresse ® and African catfish via monitoring of brain and heart activities, behavioral responses to noxious stimuli and meat quality. Dry electro-stunning (150 V, AC + DC, 100 Hz) of Claresse ® for 0.7 ± 0.2 s (mean ± SD) resulted in unconsciousness for 48 ± 15 s, fulfilling the welfare requirements for obtaining pre-slaughter unconsciousness in less than 1 s. Current input for 5.2 ± 0.5 s with a measured current of 0.57 ± 0.16 A followed by chilling, resulted in prolonged unconsciousness for 124 ± 20 s in Claresse ®. Loss of behavioral responses to noxious stimuli and then death within 5 min in 9 out of 10 African catfish resulted from stunning for 9.1 ± 0.4 s (0.91 ± 0.18 A) followed by decapitation. The meat quality did not reveal any difference in color between electro-stunned (0.76 A, 150 V, AC + DC for 15 s) and chilled-only Claresse ®. Although flesh acidification was significantly higher in the stunned group on the day of the experiment, after 24 h the groups showed similar pH changes for the next six days. We conclude that dry electro-stunning (150 V, AC + DC) followed by chilling and decapitation is a reliable method for industrial pre-slaughter unconsciousness of Claresse ® and African catfish and stunning (150 V, AC + DC) leaves no significant effect on flesh quality of Claresse ® compared to chilling method.

Utilization of nitrogen and energy from diets containing protein and fat derived from either goat milk or cow milk

Consumption of whole milk and related dairy products has decreased considerably as a result of negative aspects associated with the consumption of saturated fats. The main difference between the composition of goat milk and cow milk concerns the composition of the fat, that of goat milk containing a larger proportion of medium-chain triglycerides. The metabolic utilization of these compounds is fundamentally oriented towards their use as sources of energy, and they may even contribute to the synthesis of proteins. This study was carried out, using 40 rats at weaning, in order to determine whether, on the basis of their fat and protein composition, there is any difference between the nutritional utilization of the N and the energy from goat and cow milk. Eight animals were killed on arrival at the laboratory, and the rest were divided into four groups of eight animals and killed at the end of the experiment. Each group was given a different diet: diet 1 contained fat and protein from goat milk; diet 2 had fat from cow milk and protein from goat milk; diet 3 had fat from goat milk and protein from cow milk; diet 4 had fat and protein from cow milk. The animals were allowed to feed ad libitum for 30 d and a balance assay was performed during the final 7 d to determine N and energy utilization. At the same time and by the comparative slaughter method, the protein and fat deposition for each group was established. It was concluded that goat milk protein is more digestible than that of cow milk. Moreover, the metabolic utilization of digestible N was found to be dependent on the sources of both the protein and the fat in the diet; a higher degree of utilization was recorded for the digestible N obtained using diets with protein or fat from goat milk. Consumption of diets with goat milk fat led to a lower level of thermogenesis associated with protein oxidation and a higher one for that associated with fat oxidation, which in turn implied a protein-sparing effect of the goat milk fat. These results should be taken into account when deciding upon the type of goat milk to be used (whole, skim or semi-skim), in accordance with the dairy product to be produced from this milk.

Contested Rituals: Circumcision, Kosher Butchering, and Jewish Political Life in Germany, 1843–1933 (review)

Reviewed by: Contested Rituals: Circumcision, Kosher Butchering, and Jewish Political Life in Germany, 1843–1933 Richard S. Levy Contested Rituals: Circumcision, Kosher Butchering, and Jewish Political Life in Germany, 1843–1933, by Robin Judd. Ithaca and London: Cornell University Press, 2007. 283 pp. $45.00. When writing about an aspect of the German-Jewish experience that does not have to do with victimization, one of the most difficult things to do is to escape what one author has called the “paper ghetto,” that is, the perfunctory treatment of Jewish issues in separate sections or chapters of books devoted to mainstream German history. Robin Judd overcomes this difficulty by embedding her study of circumcision and kosher slaughtering from the 1840s to 1933 in the larger German story. Like all good history, hers spares us none of the subject’s rich complications. Arguments that began within the Jewish community concerning the defining nature of religiously prescribed rites soon became a matter of lively interest to non-Jews, the controversies surrounding ritual slaughter winning by far the greater attention. State and municipal authorities, the medical establishment, the animal rights movement, and antisemites intervened repeatedly in the debates centering on the two rituals that most clearly separated Jews from non-Jews. Judd corrects the commonly held view that opposition to circumcision and especially kosher slaughtering was always and everywhere simply an antisemitic pretext. She distinguishes degrees of antisemitism in anti-kosher slaughtering campaigns and does not assume its centrality or its significance where bans and partial bans were enacted before 1917. In the Weimar era, the Nazis commandeered the movement against circumcision and kosher butchering and intensified the antisemitic rhetoric that had always portrayed both practices as irrefutable evidence of Jewish cruelty and the futility of trying to integrate Jews into German life. During the imperial era, antisemitism often made its way into public discourse, but it seems only rarely to have swayed governmental action. There were many in the animal rights movement who thought the Jewish method of animal slaughter to be inhumane but who nevertheless distanced themselves from antisemitic arguments and even called for exempting Jews from the general reforms they advocated. The practices also became embroiled in a tangle of jurisdictional disputes at a time when state [End Page 155] and local governments sought to extend their reach by regulating economic activity, safeguarding food supplies, and policing public hygiene. How the state should balance the rights of religious minorities against the larger public good was a source of ongoing conflict. All this is laid out in meticulously researched detail and admirably clear prose. Jews by and large rallied to the defense of Judaism, even as most of them became less and less observant. ( Judd estimates that perhaps fifteen to twenty percent kept kosher by the 1920s. Liberal [Reform] Jews constituted the majority of the community as early as 1870.) In 1886, national campaigns against kosher slaughtering politicized Germany’s Jews, who saw a threat to their civic as well as their religious freedom and responded in a new way. The traditional timid petitioning of the powerful or resigned silence gave way to vigorous action. Nearly a decade before the founding of the Centralverein, the main vehicle of Jewish self-defense from 1893 until the 1930s, Jews carried their fight into the public sphere. Having made this revisionist point, Judd then spells out what it meant. Jewish organizations and individuals—often in conflict with one another—forged an activist network that was able to exploit modern techniques in fund-raising, public relations, and the exerting of economic and political influence. Their defense used every available argument, from the insistence that the method was in fact humane to stirring appeals for religious toleration. They often made common cause with the Catholic Center Party to protect the free practice of religion. Jews learned how to behave politically and were successful in fending off national bans on kosher slaughtering and having several local prohibitions repealed. In 1917, the Bundesrat approved a set of policies that safeguarded the rite, a great but short-lived victory that was undone by the Nazis in April 1933. Judd has written an important book, using a seemingly small subject to...

Species‐specific welfare aspects of the main systems of stunning and killing of farmed Carp

Species‐specific welfare aspects of the main systems of stunning and killing of farmed Carp

Systematic Review of Swine Euthanasia Methods and Welfare Measures Reported

S OF THE PROCEEDINGS 151 (p > .05); however, the amount of time at the feeder increased in all animals by day until Day C5 of the trial (p < .0001). In conclusion, in these small groups of young swine in a stable social hierarchy, the amount of time spent performing various activities did not appear to alter with a low dose of Salmonella. The welfare of these animals may not be compromised during nonsevere Salmonella infection. Systematic Review of Swine Euthanasia Methods and Welfare Measures Reported Christa Irwin, Gabriel Young, Suzanne T. Millman, Scanlon Daniels, Sherrie Niekamp, and Alex Ramirez Department of Veterinary Diagnostic and Production Animal Medicine, Iowa State University, Ames Department of Biomedical Sciences, Iowa State University, Ames Department of Population Medicine, Ontario Veterinary College, University of Guelph, Guelph, Ontario, Canada Circle H Animal Health, LLC, Dalhart, Texas National Pork Board, Clive, Iowa This topic reviews the process used to gather, screen for relevance, and assess the quality of current literature regarding published methods of swine euthanasia as well as the summary of the results of the data analysis, including a description of the welfare measures included in papers describing euthanasia. More than 4,500 citations have been collected using terms for “euthanasia,” “slaughter methods,” and “swine”; preliminary screening removed articles that were either not relevant to the topic of swine or euthanasia/slaughter methods or not in English. The second level of screening segregates primary research articles from editorials/opinions, surveys, or other narrative reviews. Only primary research is used for the final quality assessment review and analysis, but review papers are used to check the thoroughness of the reference list. The final set of literature evaluates and compares measurements of pain and aversion, the achievement of death, and other physiologic parameters described in the euthanasia paper. The Correspondence should be sent to Christa Irwin, College of Veterinary Medicine, Veterinary Diagnostic and Production Animal Medicine, Iowa State University, Veterinary Medicine Research Institute Building 4, Ames, IA 50011. Email: cirwin@iastate.edu D o w n l o a d e d B y : [ C a n a d i a n R e s e a r c h K n o w l e d g e N e t w o r k ] A t : 1 5 : 2 9 1 9 A u g u s t 2 0 0 9 152 ABSTRACTS OF THE PROCEEDINGS intent of this research is to provide this scientific body of literature to swine veterinarians and the swine industry as well as identify areas of opportunity where more research is needed. Further, the intent is to highlight areas where reporting is deficient or incomplete and improve the quality of reporting of papers describing euthanasia. Characterization of Lesions in U.S. Cull Sows Lori Layman, Mark Knauer, Ken J. Stalder, Locke A. Karriker, James McKean, Timo Serenius, Tom Baas, and Colin Johnson Veterinary Diagnostic and Production Animal Medicine Department, Iowa State University, Ames Animal Science Department, Iowa State University, Ames Physical and reproductive conditions of 3,158 cull sows from 2 U.S. Midwestern harvest facilities were assessed. Body condition, feet, shoulders, teeth, lungs, and reproductive tracts were visually evaluated for gross lesions at harvest. Based on the observations of this study, body condition score (BCS) was associated with several abnormal conditions of sows. Foot-related lesions (overgrown toes, foot pad lesions) represented the most frequently documented lesions. Temporal associations of the interactions between lesions and BCS are unknown. Even though causal relations were not established by this study, the strong associations observed suggest that sows who do not respond to increased feeding with improved BCS could reasonably be expected to have additional lesions that may impact performance and welfare. On-farm management practices may be related to 1 or more lesions (including foot lesions) that had a high prevalence in this study. Farm management practices and nonhuman animal welfare could not be evaluated with this study so no extrapolation can be given to the type of animal housing or the antemortem behavior of these sows. Correspondence should be sent to Lori Layman, Veterinary Diagnostic and Production Animal Medicine Department, Iowa State University, 1720 Veterinary Medicine, 1600 South 16th Street, Ames, IA 50011. Email: llayman@iastate.edu D o w n l o a d e d B y : [ C a n a d i a n R e s e a r c h K n o w l e d g e N e t w o r k ] A t : 1 5 : 2 9 1 9 A u g u s t 2 0 0 9

OPINIÃO PÚBLICA E EDUCAÇÃO SOBRE ABATE HUMANITÁRIO DE PEIXES NO MUNICÍPIO DE ARAUCÁRIA, PARANÁ

Society is in need of information regarding fish welfare, including sentience and suffering through fish farming and slaughter methods. The objectives of this work were: (1) to increase knowledge regarding public opinion on fish humane slaughter; and (2) to evaluate the effectiveness of education of fish cleaners on the fair regarding fish humane slaughter. Interviews were applied in two scenarios: on a Municipal Live Fish Fair and on a bus station. In the fair 88.0% of 314 respondents affirmed that fish feel pain; and on the bus station, 86.9% of 43 interviewed people affirmed the same; 55.7% reported to buy and transport live fish in dry plastic bags, characterizing slow death by asphyxiation, as opposed to 39.5% respectively. From interviewed people, 85.0% and 89.0% believe that some of the slaughter methods cause fish suffering; 52.9% and 44.1% affirmed this suffering affect meat quality, respectively. Of all people, 91.1% did not have any information regarding humane slaughter. Of the cleaners, 83.3% adopted the humane slaughter procedure taught and 75.0% affirmed that the technique facilitated the cleaning work. It is important to educate society in terms of fish sentience and its implications, especially in terms of their welfare and humane slaughter. KEY WORDS: Animal welfare, Brazil, sentience.

Effects of slaughter methods on physical, biochemical and microbiological quality of rainbow troutOncorhynchus mykissand mirror carpCyprinus carpiofilleted in pre-, in- or post-rigor periods

Rainbow trout Oncorhynchus mykiss and mirror carp Cyprinus carpio were slaughtered by either percussion or asphyxiation. For determination of the physical (texture value) and biochemical quality attributes [pH, lactic acid, total volatile basic nitrogen (TVB-N), and malondialdehyde (MDA) values] of trout and carp, the fish were filleted immediately (within 2 h), 12 h after harvest (pre-rigor), 24 and 36 h after harvest (in-rigor), and finally 48 and 60 h after harvest (post-rigor). For microbiological quality attribute (mesophilic and psychrophilic bacteria count) analyses, the fish were filleted immediately (within 2 h) after harvest (pre-rigor), 24 h after harvest (in-rigor) and 48 and 72 h after harvest (post-rigor). By percussion slaughtering followed by pre-rigor filleting, it was possible to process rainbow trout and mirror carp without inflicting excessive handling stress. Percussion slaughter delayed onset of rigor and the percussion-slaughtered fish exhibited a long pre-rigor period (≈24 h), giving plenty time for pre-rigor processing. Percussion slaughtering and pre-rigor filleting of fish was considered to be superior to the traditional asphyxiation slaughtering with respect to texture, TVB-N and MDA attributes.

Assessment of body composition in pediatric patients with cystic fibrosis

Cystic fibrosis (CF) leads to pathological changes in organs that express the cystic fibrosis transmembrane conductance regulator (CFTR), including secretory cells of the digestive tract and the pancreas. Maintaining nutritional sufficiency is challenging for CF patients and therefore accurate monitoring is important for their clinical management. The objectives of this study were to evaluate the effectiveness of skinfold measurements as an accurate method for determining body composition (fat mass (FM) and lean body mass (LBM)) of this population, using dual-energy X-ray absorptiometry (DEXA) as a gold standard comparison and to determine the most accurate equation for this calculation in children with CF. Fifty-five pediatric patients with CF participated in the study. FM and LBM calculated via four methods: Slaughter, Durnin, Durenberg (2-site and 4-site). The relationship between the methods and DEXA results were estimated by intraclass-correlation coefficient (ICC) and Bland and Altman analyses. The Slaughter method was the most accurate (ICC of 0.92 for FM and 0.99 for LBM) and displayed the least bias over the range of FM and LBM in CF patients. In addition, the results of Bland Altman analyses comparing each skinfold method to DEXA, revealed that the results were evenly distributed along the range of values for the Slaughter calculation, whereas the other three methods under and over estimated % fat results at the upper and lower ends of the range respectively. We therefore conclude that the Slaughter method may be used for body composition assessment of pediatric CF patients. This provides clinical teams with a simple, accurate and non-invasive method that can be used to monitor nutritional status in pediatric patients with CF.

Effect of electrical stunning at slaughter on the quality of farmed turbot (Psetta maxima)

Food quality aspects of farmed turbot (Psetta maxima) were compared following two methods of slaughter: the current commercial method, by immersion in an ice slurry, which is then dewatered after approximately 20 min, or by first humanely, electrically stunning the fish using a prototype commercial stunner, before immersion in an ice slurry, which is dewatered after 20 min. Quality was assessed for up to 10 days of storage on ice following slaughter. No differences were found between the slaughter methods in terms of an overall carcass quality: overall appearance, haemorrhage, damage, burst gall bladder, staining of the body cavity by leakage from the gut or damage to the spine. No detectable difference was found between the treatments using the industry standard freshness scoring system, the Quality Index Method. Both groups of fish were classified as ‘Fresh’ after 10 days of storage on ice. Using objective measurements of colour, no differences between fish from either treatment were found in fillet colour. Changes in flesh pH were similar in electrically stunned and traditionally killed fish with a mean pH (±SE) at 2 h post-mortem of 6.80±0.027 declining to 6.44±0.032 at 24 h post-mortem. Humane electrical stunning of turbot at slaughter neither detectably improved nor decreased product quality as measured between 1 and 10 days of storage on ice.

Composição corporal e exigências nutricionais em cálcio e fósforo de cordeiros Santa Inês em pastejo no semi-árido

This work aimed to evaluate the body composition and the calcium and phosphorus nutritional requirements of Santa Inês lambs under rangeland conditions in the semi-arid region of Brazil. Thirty-two castrated lambs between 3 to 4months old were used, with an initial mean body weight of 15.8 kg &plusmn; 1.4 kg. Of these, eight were slaughtered in the beginning of the experiment to provide the initial body composition (“Reference Animals” of the comparative slaughter method). The other animals were divided randomly in groups of three, as the lambs reached 15 kg. The three levels of food supplementation were randomly assigned to the lambs in each group (block). When the first animal in each group reached 30 kg, the whole group was slaughtered. The animals were kept in native rangeland enriched with buffelgrass (Cenchrus ciliaris L. cv. Biloela). Their diets were supplemented daily with three levels of concentrate mixture (0.0, 1.0 and 1.5% of their body weight). The estimated values of body composition, in g kg-1 of empty body weight, ranged from 14.91 g to 17.11 g for Ca, and from 5.33 g to 6.08 g for P. The net requirements gain of 15-to-30-kg lambs, in g kg-1 gained in live body weight, ranged from 9.4 mg to 10.8 mg for Ca, and from 3.76 mg to 3.89 mg for P.

Composição corporal e exigências líquidas de proteína e energia de bovinos de quatro grupos genéticos terminados em confinamento

Objetivou-se neste estudo avaliar a composição corporal e as exigências para crescimento de bovinos de quatro grupos genéticos em confinamento. Utilizou-se a metodologia de abate comparativo, com delineamento inteiramente ao acaso, com quatro tratamentos: Nelore (NE), ½ Aberdeen Angus + ½ Nelore (AN), ½ Canchim + ½ Nelore (CN) e ½ Simental + ½ Nelore (SN). Quarenta e sete animais castrados, com média de 22 meses de idade e peso em jejum de 310 kg, foram confinados por 101 dias. A dieta experimental continha 13,34% de proteína bruta (PB) e 71,81% de nutrientes digestíveis totais (NDT). A composição do corte da 9ª-10ª-11ª costelas foi utilizada para estimar a composição do corpo vazio. Bovinos AN (428 kg) e SN (410 kg) não diferiram quanto ao peso final de corpo vazio, que foi semelhante também entre os animais CN, NE e SN (389, 390 e 410 kg, respectivamente). Animais AN tiveram maior proporção de gordura no corte das costelas, porém menor proporção de músculo. A menor porcentagem de ossos no corte das costelas foi observada nos animais da raça Nelore. Os grupos AN e SN tiveram maior proporção de extrato etéreo (EE) e menor porcentagem de água no corpo vazio no momento do abate. Animais AN, NE e SN não diferiram quanto à taxa de deposição de energia (6,06, 5,20 e 5,80 Mcal/dia, respectivamente). O grupo AN não diferiu dos grupos CN e SN quanto à proporção de EE na composição do ganho de peso do corpo vazio. Bovinos SN apresentaram maior exigência de proteína (0,164 kg/kg de ganho de peso vazio - GPV) e os animais AN e CN, o menor valor (0,140 e 0,142 kg/kg de GPV, respectivamente). Animais AN tiveram a maior exigência líquida de energia para ganho (4,685 Mcal/kg de GPVz).

Exigência de energia de mantença e composição corporal e do ganho de vacas de corte adultas de três grupos genéticos confinadas

Neste trabalho, foram estimadas as exigências de mantença de energia líquida (ELm) e metabolizável (EMm) e as mudanças na composição corporal e no ganho de vacas adultas não-gestantes e não-lactantes confinadas. Foram utilizadas 36 vacas, 12 Nelore (NEL), 12 F1 Pardo-Suíço-Nelore (PSN) e 12 F1 Red Angus-Nelore (RAN). As alterações na composição corporal dos animais durante o período experimental foram estimadas utilizando-se a técnica do abate comparativo: quatro animais de cada grupo genético foram alocados, aleatoriamente, nos tratamentos abate inicial (AI), alimentação restrita (AR) e alimentação ad libitum (AL). Os animais AR receberam, no período experimental, níveis de proteína e energia 15% acima da mantença e os AL, ração ad libitum, para ganho de 1,1 kg/dia. Os animais AI foram abatidos no início do experimento e os AR e AL 120 dias depois. Em todos os animais abatidos, foram estimadas as proporções corporais dos tecidos muscular, adiposo e ósseo, além dos conteúdos corporais de proteína, gordura e energia. Na estimação da ELm e da EMm, foram empregados modelos linear e não-linear. Os grupos genéticos não diferiram quanto às exigências de ELm e EMm, expressas em peso vivo em jejum (kcal/kg0,75/dia PVJ). Quando utilizados os modelos linear e não-linear, os valores de ELm encontrados foram de 80,7 e 83,6 kcal/kg0,75/dia PVJ e os de EMm, 109,9 e 128,0 kcal/kg0,75/dia PVJ, respectivamente. Os conteúdos de proteína por unidade de peso corpo vazio (PCVZ) e do ganho (GPCVZ) não diferiram entre os grupos genéticos, porém, os animais NEL apresentaram maior concentração de gordura e energia por kg PCVZ e GPVCZ para mesmo peso vivo.

Effect of electrical stunning at slaughter on the carcass, flesh and eating quality of farmed sea bass (Dicentrarchus labrax)

Food quality aspects of farmed sea bass (Dicentrarchus labrax) were compared following two methods of slaughter: the normal commercial method of killing, by immersion in an ice slurry, or by first electrically stunning the fish, before immersion in an ice slurry. Quality was assessed for up to 10 days of storage on ice after slaughter. No differences were found between the slaughter methods in terms of an overall sensory evaluation of cooked fillets, or in terms of overall carcass quality: overall appearance, internal and external haemorrhage, fin damage, burst gall bladder, staining of the body cavity by leakage from the gut or damage to the spine. Using objective measurements of colour, no differences between fish from either treatment were found in terms of external colour or colour of the fillets. A chemical analysis of flesh nucleotide breakdown products as well as the freshness indicator Ki value did not differentiate the two treatments nor did the industry standard freshness scoring technique (QIM, quality index method), over 10 days of storage on ice. Flesh pH was marginally lower in electrically stunned fish at 4 h post mortem (6.42 cf 6.56) but by 24 h, pH in fish from both treatments had decreased to a similar level (6.22). Humane electrical stunning of sea bass at slaughter neither measurably improved nor decreased product quality for between 1 and 10 days of storage on ice. Electrical stunning accelerated the pattern of onset and resolution of rigor mortis. If electrical stunning were to be widely adopted, re-education of buyers would be necessary as rigor mortis is currently used by buyers as a proxy measure of fish freshness.

Comparative efficacy of an indigenous ‘inactivated vaccine’ using highly pathogenic field strain of Mycobacterium avium subspecies paratuberculosis ‘Bison type’ with a commercial vaccine for the control of Capri-paratuberculosis in India

Johne's disease (JD) is endemic in goatherds located at Central Institute for Research on Goats, Makhdoom, since 1979 and lately it has been reported from farmer's herds in equal frequencies. Despite using test and slaughter method for the control of JD for more than 25 years in these herds, incidence of JD has not been reduced. Efficacy of ‘indigenous vaccine’ containing native ‘Bison type’ genotype of Mycobacterium avium subspecies paratuberculosis (MAP) was compared with commercial vaccine using challenge studies with homologous strain of MAP. Goat kids (85) were randomly divided in to three groups. Kids were vaccinated with 1 ml of vaccine subcutaneously and Sham-immunized with 1 ml of sterile PBS. All kids except 3 in each group were challenged twice at 75- and 275-day post-vaccination (DPV). Four goats each from three groups were sacrificed at 200-day post-challenge to evaluate carcass and histopathologically for vaccine and challenge response in kids of different groups. Samples (blood, serum and fecal) were screened for LTT, ELISA and shedding of bacilli and data on live animal traits, mortality and experimental sacrifice were compared. Average body weights gained by goats in three groups at different stages of trials (0, 1–75, 76–275, 276–425 DPV) showed marked improvements in performance of vaccinated groups over ‘Sham-immunized’ group. Effect of vaccines against challenge became visible in terms of body weights gained at 276–425 DPV (‘Bison’ group gained significantly higher body weights than ‘Sham-immunized’). Mortality was significantly less in two vaccinated as compared to ‘Sham-immunized’. Vaccinated groups also had significant stimulation and sero-conversion for cell mediated and humoral immune response, respectively as compared to ‘Sham-immunized’. Results of post-challenged fecal culture showed significant reduction in shedding of MAP in both vaccinated groups than in ‘Sham-immunized’. There was significant improvement in external and internal body traits and histological lesions in case of vaccinated than ‘Sham-immunized’ group.

Net energy evaluation of feeds and determination of net energy requirements for pigs

Feeds for pigs can be attributed different energy values according to, first, the step considered in energy utilization (DE: digestible energy, ME: metabolizable energy and NE: net energy) and, second, the method used for estimation at each step. Reference methods for evaluating DE content are based on in vivo digestibility measurements; indirect estimates of DE values are obtained from in vitro methods or prediction equations based on chemical characteristics. Methods have also been proposed for estimating urinary energy (and gas energy to a smaller extent) in order to calculate ME content from DE value. The NE values originate from energy balance studies (slaughter methods or, more commonly, indirect calorimetry measurements in respiration chambers) and their compilation allows the calculation of NE prediction equations based on digestible nutrient contents or DE or ME contents. Such equations are applicable to both ingredients and compound feeds. They may differ between origins according to the fractionation method of organic matter or assumptions such as the NE requirement for maintenance (or fasting heat production). These measurements represent the bases for establishment of energy values in feeding tables. Results indicate that energy digestibility of feeds is negatively affected by dietary fibre content but this negative effect is attenuated with body weight increase, which suggests that feeds should be attributed DE values according to pig BW; in practice, at least two different DE values, one for growing-finishing pigs and one for mature pigs (reproductive sows), are recommended. The energy digestibility of pig feeds can also be affected by feed processing (pelletting, extrusion, etc.). Efficiency of ME utilization for NE averages 74-75% for conventional pig diets but it is directly dependent on diet chemical composition with efficiencies higher for ME from fat (90%) or starch (82%) than from protein or dietary fibre (60%). The hierarchy between feeds and results of least-cost formulation are then dependent on the energy system with overestimation of protein rich feeds and underestimation of starch and/or fat rich feeds in the DE or ME systems. The NE system provides an energy value which is the closest estimate of the "true" energy value of a feed; it predicts more accurately the performance of the pigs and allows implementing new feeding approaches such as the use of low protein and/or high fat diets. Energy requirements expressed as DE or ME can be transformed to NE requirements if we assume that the average efficiencies of DE or ME for NE are 71 and 74%, respectively. More sophisticated methods including modeling techniques can also be used for evaluating energy requirements.

Characteristics of burnt meat in cultured yellowtail Seriola quinqueradiata

In order to understand the characteristics of burnt meat in cultured yellowtail Seriola quinqueradiata, fish were kept at two different temperatures (13 and 30°C) and slaughtered by either spinal cord destruction (SCD) or suffocation in air (SA). Early postmortem changes during storage at 32°C were analyzed by rheological, biochemical, and histological methods. The burnt meat (with lightness parameter, L*≥55) was observed at 1-h storage in the SA 30°C group, at 2 h in SCD 30°C, and at 4 h in SA 13°C; meat was normal for the SCD 13°C group until 6h of storage. Breaking strength scores were higher for the normal meat (200 g/cm2) than burnt meat (70 g/cm2) at 4 h of storage. Expressible water content was higher for the burnt meat than for the normal meat. Adenosine triphosphate concentrations for the SCD groups were higher than for the SA counterparts. Moreover, pH decrease was much faster in the 30°C groups, showing pH 5.6 at 2 h of storage. A negative correlation between the pH and lactic acid contents in muscle (P<0.001) was found. Histological analysis evidenced a larger pericellular area (40%) in the burnt samples than in the normal samples (16%). It was confirmed that a higher fish-keeping water temperature and a stressful slaughter method (faster glycolytic process) were determinative factors that influence the occurrence of burnt muscle in yellowtail, and that the effect of the former is larger than the latter.

Protein Levels for Heat-Exposed Broilers: Performance, Nutrients Digestibility, and Energy and Protein Metabolism

Heat stress causes significant economic losses on broilers production due to poorer performance and carcass quality. Considering that protein has the highest heat increment among nutrients, it has been suggested that protein levels should be reduced in diets for heat-exposed broilers. Nevertheless, there are no conclusive results on the benefits of such practice, and further studies should be performed to elucidate some reported discrepancies. Thus, a trial was carried out to evaluate the effects of dietary protein levels (17, 20 and 23%) and environmental temperature (22 and 32oC) on the performance, nutrients digestibility, and energy and protein metabolism of broiler chickens from 21 to 42 days of age. Nutrients digestibility was determined by total excreta collection, and energy and protein metabolism was evaluated by comparative slaughter method. It was concluded that (1) heat exposure impairs broilers performance and increases nitrogen excretion, but do not change nutrients digestibility; (2) high-protein diets are technically feasible and promotes lower heat production for broilers reared under thermoneutral or hot environments, however, highprotein diets increases nitrogen excretion.

Influence of Slaughtering Method on Some Aspects of Quality of Gilthead Seabream and Smoked Rainbow Trout

The effects of several slaughter methods on the quality of fresh and smoked trout and fresh gilthead seabream were evaluated during storage at 2 degrees C. Electrically stunned trout had slower ATP depletion of raw muscle and lower lipid oxidation in smoked product during storage. Gilthead seabream immersed in an ice slurry (IS group) after the harvest showed a more regular ATP depletion than in fish exposed to CO2. Nevertheless, in the case of the IS group, self-initiated behaviour, response to handling and breathing all ceased only after 15-20 min, whereas carbon dioxide-stunned fish appeared dead after 5 min. However, gilthead seabream group having slower ATP depletion also showed lower lipid oxidation of muscle during storage. In both species this could be due to the rapid conversion of xanthine dehydrogenase to xanthine oxidase induced by the rapid consumption of ATP. Xanthine oxidase, in the presence of redox iron and reintroduced oxygen, can produce hydrogen peroxide and, consequently, hydroxyl radicals.

Welfare and quality of farmed trout fed high plant protein diets. 3 alternative indicators to evaluate stress in fish

Previous studies reported that diets can increase tolerance to various stressful conditions in different fish species. Consequently, the present work evaluated the effects of replacing fish meal (FM group) with an 80% of plant protein source (PV 80 group) in the diet of farmed rainbow trout (Oncorhynchus mykiss) on stress response caused by two different slaughter methods (electrical stunning and asphyxia). Plasma cortisol levels are widely employed as quantitative measure of stress (Wendelaar Bonga, 1997). However, to avoid the blood sample, it would be useful to test less invasive alternative biological matrixes such as skin mucus, faeces and caudal fin to use them especially in live fish and also invasive matrixes as muscle for post-slaughter analysis. From each experimental group twelve fish were netted, six were slaughtered by electrical stunning and six by asphyxia. From each fish, plasma, skin mucus, intestinal content, caudal fin tip and muscle were rapidly collected and frozen for cortisol evaluation by RIA (radioimmunoassay). Data on plasma cortisol were submitted to analysis of variance using the GLM procedure (STATISTICA, 2006) according to a bi-factorial arrangement (2x2) with slaughter methods and diets as main variability factors. Pearson’s linear regression was used to correlate cortisol values in different matrixes. Statistical significance was taken as P<0.05. Results showed that plasma cortisol was significantly higher in groups slaughtered by asphyxia (P=0.002) and no differences were found in plasma cortisol between the different diets (P=0.34). Plasma cortisol was compared with the level in the other matrixes showing a positive correlation with skin mucus and intestinal content (r=0.57 and r=0.58, respectively). The low correlation of plasma cortisol with muscle and fin (r=0.2 and r=0.1, respectively) is in contrast with previous study on trout transport stress (unpublished data). This is probably due to the reduced vitality of fish during asphyxia or to insufficient time (20’) for the steroid to reach the highest levels that easily diffuse into muscle and fin. In summary, the electrical stunning is preferable as regard fish welfare and a diet in which fish meal is replaced by plant proteins could not influence the stress response to slaughter. Moreover less invasive matrixes such as mucus and faeces could be good indicators of the stress level in fish.