Slaughter Method Research Articles

Iron Content in Wild Animal Meats: A Systematic Review Comparing Mammals and Birds

This study explores the iron content in wild animal meats, a critical component of the diets of several Indigenous Peoples and Local Communities (IPLC) worldwide. Our research aimed to: (i) characterize the iron content in the muscles and viscera of wild mammals and birds, and (ii) assess whether wild bird muscle contains less iron than wild mammal muscle. Employing a systematic literature review guided by PRISMA standards and utilizing databases such as Web of Science, Medline/PubMed, and Scopus, we analyzed data from eight pertinent studies. No data regarding bird viscera were identified. Our findings indicate a significant disparity in iron content between the viscera and muscle of mammals, with the former exhibiting over six times the iron content (mean of 15.25 mg per 100g) compared to the latter (mean of 2.24 mg per 100g). Contrary to our hypothesis, the iron content in the muscles of birds (mean of 3.75 mg per 100g) and mammals did not significantly differ (p=0.120), with birds, descriptively, demonstrating a nearly 70% higher iron content. This unexpected result may be attributed to the influence of slaughter methods, such as gunshot, which prevents external bleeding, or animal behavior. Our research underscores the necessity of considering slaughter techniques in nutritional assessments of meat. These findings not only contribute to our understanding of nutritional values of wild meat but also prompt further investigation into their role in human diets, especially among IPLC.

Effects of different slaughtering methods on the biochemical characteristics and quality changes of tilapia (Oreochromis niloticus) during cold storage

Inappropriate slaughter methods can lead to differences in fish quality. In the past few years, few studies have focused on the effects of different slaughter methods on the postmortem effects of tilapia, especially the cold storage of tilapia after slaughter. The aim of this study was to investigate the effects of different slaughter methods on the biochemical characteristics and quality changes of tilapia during cold storage. In terms of blood and plasma parameters, the CS sample had lower levels of lactate dehydrogenase (LDH), cortisol (COR), and glucose (GLU) than the other samples. The results of K-value and FAAs showed that CS and ASCN groups were beneficial to prolong the freshness life of tilapia during cold storage. The texture properties of CS group were better. In summary, group CS is more conducive to prolonging the fresh life of refrigerated tilapia and is a recommended method of slaughter.

Untargeted Metabolomics Based on UHPLC-HRMS for Authentication of Chicken Meat Supplied by Different Slaughter Methods of Halal, Non-Halal, and Shubha

Untargeted Metabolomics Based on UHPLC-HRMS for Authentication of Chicken Meat Supplied by Different Slaughter Methods of Halal, Non-Halal, and Shubha

Effects of different slaughtering methods on the energy metabolism, apoptosis process and quality of grouper (Epinephelus fuscoguttatus) during cold storage at 4 °C.

The aquatic processing industry is increasingly aware of the need to ensure that slaughtering is carried out under high welfare standards, so there is a need to explore the impact of slaughter methods on fish fillets. This study aimed to investigate the effects of different slaughtering methods (M1, lethality by hammering; M2, gas mixture causing death; M3, lethality by clove oil anesthesia + ice slurry; M4, lethality by ice slurry; M5, lethality by gradient cooling) on the energy metabolism, apoptosis and flesh mass in grouper (Epinephelus fuscoguttatus). Therefore, 120 fish (24 per treatment) were slaughtered by the five methods. The results showed that the succinate dehydrogenase (SDH) enzyme activity of M5 sample was higher. The serum glucose level of M2 samples and DAPI staining fluorescence of M2 samples were the highest, indicating that the stress response of M2 was strong. In addition, the texture, pH, total volatile basic nitrogen (TVB-N), thiobarbituric acid (TBA) and K value results showed M5 samples had better flesh quality. Gradient cooling lethality had the least effect on oxidative damage and apoptosis in grouper during cold storage as the gradient cooling lethality had the least effect on antioxidant enzyme activities. © 2024 Society of Chemical Industry.

Effect of Poor Post-Slaughter Handling on Physicochemical and Microbial Quality of Fresh Broiler in Bangladesh

The slaughtering method and post-handling play an important role in meat processing. Countries followed different slaughtering methods, post-handling, and preservation techniques for post-slaughtered meat. Stress-oriented slaughtering, unhygienic handling, processing, and improper preservation are triggering factors of rapid oxidation and microbial proliferation in meat during storage. Bangladesh is a Muslim-oriented country but many vendors do not follow the halal slaughtering, and handling of meat in an unhygienic way due to a lack of food safety knowledge. Thus, the study aims to assess the effect of poor post-slaughtering handling practices on the physiochemical properties which include moisture, ash, protein content, fat content, drip loss, cooking loss, water holding capacity, pH, fat oxidation, color, heme iron, mineral content, and microbial qualities of fresh samples by total plate count during 0 days, 15 days and 30 days frozen storage at -18ºC. The live broiler was purchased randomly and slaughtered instantly from different slaughter shops in Jashore City, Bangladesh. The laboratory analysis was performed following the standard method of meat sample analysis. The outcome of this study revealed that heme iron content, minerals like Ca, Fe, Zn, and lightness values decreased significantly (p < 0.05) during 30 days of storage at -18 ºC. Post-handling had no significant effect (p > 0.05) on protein and ash content at 0 and 15 days of storage but slowly decreased with increasing storage time. The continuous increase in pH, cooking loss, and TBARS value indicate rises in lipid oxidation noticed in all samples, especially during 16-30 days of frozen storage (p < 0.05). The total viable count significantly raised (p < 0.05) and reached the highest value of 7.27 log10 CFU/g and 7.44 log10 CFU/g respectively after 15 days and 30 days of frozen storage compared to fresh condition. Bacteriologically meat samples were of very poor quality during storage compared to fresh ones.

Extrusion can ameliorate negative effects of molecular structures of brewer's spent grain on energy contents and amino acid digestibility in growing pigs.

The objectives of this study were to investigate the effects of extrusion on the chemical compositions, surface structure, and molecular structure of brewer's spent grain (BSG), as well as to determine the digestible energy (DE), metabolizable energy (ME), apparent total tract digestibility (ATTD) of nutrients and energy, and amino acid (AA) digestibility of extruded BSG when fed to growing pigs. Firstly, we determined the changes in chemical compositions and molecular structure of both non-extruded and extruded BSG. In Exp. 1, eighteen growing pigs were fed three different diets including one corn-soybean meal basal diet and two experimental diets containing 20% BSG with or without extrusion. Feces and urine were collected to determine the ATTD of nutrients and energy, DE, and ME of extruded or non-extruded BSG. In Exp. 2, eighteen growing pigs were fed three different diets including 30% BSG with or without extrusion, and an N-free diet. Ileal digesta was collected through the slaughter method to determine the apparent ileal digestibility (AID) and standardized ileal digestibility (SID) of AA of extruded or non-extruded BSG. The results showed that extrusion reduced the neutral detergent fiber, hemicellulose and cellulose contents in BSG, and increased the Arg, Asp, Glu, Ser, Tyr, total indispensable AA and total AA contents of BSG, altered the surface structure of BSG, increased the peak absorbance in amide I and amide II height, amide II and amide (I+II) area, α-helix height, decreased β-sheet height, and weakened band intensities in cellulosic compounds (CELC) area, structural carbohydrates (SCHO) area, carbohydrates area (CHO) peak 2 and 3 height, the area ratio of CELC: CHO and CELC: SCHO. Moreover, DE and ME values and ATTD of energy, dry matter, crude protein, acid detergent fiber, neutral detergent fiber, cellulose and hemicellulose increased (P < 0.05) when pigs were fed extruded BSG diets. The AID and SID of Arg, His, Lys, Val and Gly increased, whereas the AID and SID of Ile and Leu decreased when pigs were fed extrusion diets (P < 0.05). Our study found that the ATTD of nutrients and AA digestibility in pigs were positively correlated with the molecular structure of proteins, and negatively correlated with the molecular structure of carbohydrates (P < 0.05). These findings suggested that extrusion had the potential to improve the nutrient digestibility of BSG by altering its chemical compositions, surface structure, and molecular structure.

Impact of slaughter method on stress in organic common carp (&lt;i&gt;Cyprinus carpio&lt;/i&gt;)

Impact of slaughter method on stress in organic common carp (&lt;i&gt;Cyprinus carpio&lt;/i&gt;)

Effects of electrical and percussive stunning on neural, ventilatory and cardiac responses of rainbow trout

From an ethical standpoint, it is imperative that rainbow trout (Oncorhynchus mykiss) are humanely slaughtered, which entails that they are rendered unconscious immediately by a stunning method and remain so until death. The efficacy of electrical stunning following dewatering (i.e., in-air electrical stunning at intensities of 50 to 920 mA and durations of 5 to 30 s) and percussive stunning, both advocated as humane stunning and/or killing methods, are evaluated here for this species via the presence or absence of visually evoked responses (VERs). In addition, ventilatory and cardiac responses were evaluated to elucidate the physiological basis for the lethality of both methods. While the present study was unable to determine the capability of in-air electrical stunning to induce immediate unconsciousness, our findings revealed that irreversible stuns were induced by both in-air electrical stunning (i.e., ∼25 to 70% of individuals did not recover VERs across the various combinations of stunning intensities and/or durations) and percussive stunning (i.e., ∼100% of individuals did not recover VERs). The efficacy of in-air electrical stunning for permanently abolishing VERs was marginally, but significantly, impacted by stun intensity (i.e., explained 8% of the variation). Furthermore, due to substantial inter-specific variability and a limited sample size, significant impacts of stun intensity and/or duration on the recovery of VERs in reversibly stunned individuals were not detected in the present study (i.e., VERs recovered between <0.5 to 28.8 min). Further investigation is therefore necessary before in-air electrical stunning can be endorsed as a standalone humane slaughter method for rainbow trout. This includes determining its capacity to induce immediate unconsciousness, as well as to identify additional factors that could be modified or enhanced to improve its efficacy. Furthermore, since death following in-air electrical stunning likely entails a prolonged process involving ventilatory failure, hypoxemia, and subsequent vital organ malfunction, rather than immediate cardiac arrest or central nervous system failure, the sequential use of methods such as percussive stunning is recommended to safeguard the welfare of rainbow trout during slaughter.

RELIGIOUS SLAUGHTER AND ANIMAL WELFARE: A COMPARATIVE LEGAL STUDY OF KAZAKH AND EUROPEAN LEGISLATIONS

n Kazakhstan, until recently, issues regarding the responsible and humane treatment of animals were unregulated. The first law, “On Responsible Treatment of Animals,” was adopted in 2021, defining the place of animals in the system of public relations and guaranteeing their protection. However, the law includes an exception regarding the slaughter of animals during religious ceremonies, which has caused discussions and disputes between public organisations for the protection of animals and religious communities. Impressive results of balancing animal welfare with religious freedom can be found in the EU. This article conducts a comparative legal study of Kazakh and some EU Member State legislations with regard to religious slaughter. Methods: This study employed various methodologies, utilising both theoretical and empirical approaches. These methodologies encompassed the comparative legal method, which allowed the authors to analyse and research foreign experience in animal rights protection to pinpoint the most important features applicable to Kazakh legislation. Statistical data was also collected to identify patterns and trends. Based on this, a forecast was made indicating a growing population, thereby suggesting an increase in animal consumption and utilisation. Therefore, this article on the protection of animal rights is a timely and relevant study. Moreover, the authors conducted an analysis of specific cases from foreign countries, aiding in the identification of the features and challenges of law enforcement practice. The dialectical method was central to examining the research problem. It enabled the identification of contradictions and interrelationships between classical and religious methods of mortification. Results and Conclusions: Based on the study’s results, several practical proposals are put forward to eliminate or regularise the existing legislative derogation in respect of religious slaughter. The present contribution concludes that the Kazakh legal framework on animal rights protection has shortcomings that require improvements by enshrining specific methods of animal slaughtering, which can be drawn on European experience.

The Effects of Slaughter Methods and Drying Temperatures on the Protein Hydrolysis of Black Soldier Fly Larvae Meal.

In recent years, the potential of insects as a sustainable protein alternative to feed the growing world population has been explored. Differences in the ways insects are processed can affect their proximate composition and digestibility. This work studied the effects of the combination of different types of slaughter methods and drying temperatures on the proximate composition, organic matter digestibility (OMd), hydrolysis degree (DH/NH2 and DH/100 g DM), total hydrolysis (TH), and hygienic and sanitary characteristics of BSFL (black soldier fly larvae) meal. Four types of slaughter methods were used including freezing (F), blanching + freezing (B), Melacide® + freezing (M), and liquid nitrogen slaughter (N). Each of these was used with three drying temperatures (50, 70, and 90 °C). A negative correlation between the acid detergent fiber (ADF) and protein digestibility parameters was obtained. The most suitable drying temperature was 70 °C, as it produced higher values of protein digestibility (DH and TH), resulting in hygienic and sanitary conditions suitable for food use. Slaughtering with liquid nitrogen and blanching was more conducive to achieving high protein digestibility results than traditional freezing or the use of Melacide®.

Evaluation of non-penetrative captive bolt stunning as a method of slaughter for white sturgeon (Acipenser transmontanus)

IntroductionPercussive stunning is a widely used and ethically supported method of stunning fish per welfare standards as part of a one- or two-step slaughter process. In this study, the use of a non-penetrative captive bolt (NPCB) gun was evaluated as an effective one-step method of improving welfare for juvenile and adult farmed white sturgeon (Acipenser transmontanus) at slaughter.MethodsA Jarvis HPS-1 NPCB was operated at pressures of 120, 135, and 145 PSI (827.37, 930.79, and 999.74 kPa, respectively) for juvenile sturgeon (n = 3 sturgeon per operating pressure) and 175, 200, and 225 PSI (1206.58, 1378.95, and 1551.32 kPa, respectively) for adult sturgeon (n = 3 sturgeon per operating pressure). Following a single strike, fish were assessed for jaw relaxation and a somatic response before being exsanguinated and transferred to an ice slurry. An hour after slaughter, fish heads were collected, and a section of cartilage containing the brain was removed and fixed in formalin for histological analysis of brain death. To evaluate fish recovery, juveniles (n = 100) and adult female sturgeon (n = 65) were monitored for two hoursafter a single exposure to 145 and 225 PSI, respectively.ResultsHistology results showed there was an effect between operating pressure and intracranial hemorrhage in juvenile sturgeon (p = 0.024). There was a greater meningeal-to-cerebral hemorrhage at 135 PSI compared to the 120 PSI group (p = 0.020) and a trend towards increased tissue damage from 120 PSI to 145 PSI (p = 0.056). Adults showed no significant difference in meningeal hemorrhage at any operating pressure. When investigating recovery rates, NPCB successfully stunned 100% of juvenile sturgeon at 145 PSI, and 225 PSI stunned 90% of adult sturgeon without recovery.DiscussionThese results demonstrate that the use of an NPCB gun is an improvement in animal welfare compared to repeated strikes, but a single application did not produce histological brain death; further research should be conducted to determine optimal pressures that result in immediate brain death.

Review: Goat and Sheep Meat Production in Indonesia

This review describes the production systems and products pertaining to goats and sheep (GS) in Indonesia. These small ruminant species are found across 38 provinces in Indonesia. Almost 99% of the GS are farmed by smallholders, with the animals either being housed in an enclosure (small shed near the farmer’s house) or in a mix of both grazing and confinement. The livestock are typically fed natural and/or artificial feed. Two sheep types, thin-tailed and fat-tailed are the most popular with smallholder producers, while Bali, Etawah, Boerawa, Jawa Randu Kosta, and Gembrong are the dominant goat breeds. As one of the biggest Muslim countries in the world, Indonesian production and consumption of GS is influenced by culture and religious systems. The Halal slaughter method applied is described, as are the religious/cultural festivals in Indonesia, which have a significant relationship on the GS demand and consumption, such as Eid al-Adha and Aqiqah. The preparation, processing, and consumption of GS meat in Indonesia are strongly influenced by the use of spices, being part of the Moluccas archipelago, also known as the “Spice islands” with over 30,000 species of spices grown. Some traditional meats and meat processing technologies in Indonesia are presented to provide insight into how GS meat is processed. The main challenges in the processing of GS meat in Indonesia and some current research on the development of GS production are presented in this paper. Implications: Goat and sheep belong to the most widely consumed meats in the world after pork, poultry, and beef. There are some reasons why GS meat has become one of the more popular protein choices for many families, of which its low-fat levels are one. GS meat is also considered one of the only meats with minimal religious taboos in the world. For these reasons, GS meat is also favored by Indonesian people in the most populous Muslim-majority country. However, information regarding goat and sheep in Indonesia is still lacking. This review aims to provide information on the distribution of GS in Indonesia over 38 provinces, the breed types that grow there, their production, and Indonesian consumption behavior, highlighting the religious festivals that cause the highest demand for these meats. This review provides information to the stakeholders of goat and sheep production chains.

Electro-Immobilisation and Fish Welfare: An Investigation into Stress, Consciousness, and Physiological Aspects During Slaughter

ABSTRACT The aquaculture industry frequently employs various slaughter methods that subject fish to inhumane conditions, resulting in significant suffering. This study examined the effects of electrical method on the welfare of farmed fish (Mesopotamichthys sharpeyi) compared to air asphyxiation. Fish captured with electricity exhibited calm behavior until death, in contrast to fish treated with air asphyxiation, which exhibited violent responses within 4 minutes of capture. The electrical method achieved a complete state of unconsciousness 7 minutes faster than air asphyxiation. Our results show that air asphyxiation raised cortisol levels more than the electrical method, with no significant difference in glucose and lactate concentrations. Electrically treated fish had higher superoxide dismutase and liver-reduced glutathione levels, while suffocated fish showed elevated GSH and liver catalase levels. Radiographs revealed no fractures or skeletal changes. Electrical stunning had no effect on gill tissue, but caused brain tissue hemorrhage, whereas air asphyxiation caused less damage. Air asphyxiation caused gill tissue issues but less brain damage. Consciousness loss is crucial for humane practices. Specific electrical currents (110V for 30s) could improve aquaculture and fish welfare.

The amino acid pattern and dynamics of body protein, body fat deposition in male and female broilers under different temperatures

The present study was conducted 1) to investigate the effects of gender and temperature on growth performance in broiler chickens and 2) to establish body protein and fat deposition curves and amino acid patterns for broilers of both genders at different ambient temperatures. A total of 432 1-day-old (d) Arbor Acres chickens with a male/female ratio of 1:1 were randomly divided into the following 4 treatment groups: the male thermoneutral group, the female thermoneutral group, the male heat stress group, and the female heat stress group. The chickens in the thermoneutral groups were kept at a comfortable temperature from 1 to 42 d, while chickens in the heat stress groups were kept at a comfortable temperature from 1 to 28 d and at a high ambient temperature from d 29 to 42. The body composition retention data were obtained by comparative slaughter method, and the models were constructed by the Gompertz model. The results revealed significant variation in body protein content (BPC) and body fat deposition efficiency (BFE) between both genders and the 2 temperatures. Moreover, a noteworthy interaction between gender and temperature was observed in terms of the BPC and protein deposition efficiency (BPE). The following equations for body protein and body fat deposition in the thermoneutral groups were obtained: Body protein weight of male broilers: [Formula: see text] ; Body protein weight of female broilers: [Formula: see text] ; Body fat weight of male broilers: [Formula: see text] ; Body fat weight of female broilers: [Formula: see text] . Where t means age (d). The following equations for body protein and body fat deposition in the heat stress groups were obtained: Body protein weight of male broilers: [Formula: see text] ; Body protein weight of female broilers: [Formula: see text] ; Body fat weight of male broilers: [Formula: see text] ; Body fat weight of female broilers: [Formula: see text] . Where t means age (d). In addition, no significant difference in amino acid content was found between different genders and temperatures. The amino acid pattern could be divided into 2 stages: 0 to 14 d and 15 to 42 d. Our equations and patterns enable a deeper understanding of the nutritional requirements in broiler chickens under various temperature conditions. This enables researchers to develop more accurate feeding programs to fulfill the growth and health requirements of broiler chickens.

Grinding as a slaughter method for farmed black soldier fly (Hermetia illucens) larvae: Empirical recommendations to achieve instantaneous killing.

At least 200 billion black soldier fly (Hermetia illucens) larvae (BSFL) are reared each year as food and feed, and the insect farming industry is projected to grow rapidly. Despite interest by consumers, producers, and legislators, no empirical evidence exists to guide producers in practicing humane - or instantaneous - slaughter for these novel mini-livestock. BSFL may be slaughtered via freezing, boiling, grinding, or other methods; however standard operating procedures (SOPs) and equipment design may affect the likelihood of instantaneous death using these methods. We tested how larval body size and particle size plate hole diameter affect the likelihood of instantaneous death for black soldier fly larvae that are slaughtered using a standard meat grinder. Larval body size did not affect the likelihood of instantaneous death for larvae that are 106-175 mg in mass. However, particle size plate hole diameter had a significant effect on the likelihood of instantaneous death, with only 54% of larvae experiencing an instant death when using the largest particle size plate (12-mm hole diameter) compared to 84% using the smallest particle size plate (2.55 mm). However, a higher percentage of instantaneous death (up to 99%) could be achieved by reducing the proportion of larvae that become stuck in the machine. We conclude by outlining specific recommendations to support producers in achieving a 99% instantaneous death rate through specific SOPs to be used with similarly designed machines. We also develop a protocol for producers that wish to test their own grinding SOPs.

Farmed yellow mealworm (Tenebrio molitor; Coleoptera: Tenebrionidae) welfare: species-specific recommendations for a global industry

Abstract Yellow mealworms (Tenebrio molitor; Coleoptera: Tenebrionidae) are currently the most farmed holometabolous insect species in the insects as food and feed industry, with over 300 billion individual mealworms reared annually. Yellow mealworm larvae are being developed for potential uses as human protein, pet, livestock and fish feed, reclamation of mycotoxin-contaminated grains, and more. Insect welfare is of great interest to consumers, producers, and academics; yet no studies have considered the species-specific welfare concerns of farmed yellow mealworms under current industry conditions. Following a model for considering farmed insect welfare, we review yellow mealworm biology and its relationships to welfare in commercial rearing facilities, including: interspecific interactions (predators, parasites, and pathogens), abiotic conditions (temperature, hydration, atmospheric gasses, lighting), nutrition (including pollutants, plastics, and hormones), intraspecific concerns (genetics, morphological defects, cannibalism, density, mating and oviposition needs, and handling-associated stress), and slaughter and depopulation methods (including anesthesia and stunning). From this review, we identify practical recommendations for improving current welfare concerns in the industry and mitigating future concerns that may appear as the industry continues to grow. Finally, we discuss future research directions that are necessary to better understand the welfare of this species.

Indirect methods for predicting the body composition of sheep of different sex classes

The aim was to evaluate the correlation and develop regression equations for the body composition of sheep of different sex classes, obtained by the comparative slaughter method, using the composition of the neck region and loin eye area (LEA). Forty-five sheep of three sex classes (15 intact males, 15 castrated males and 15 females) received three feeding levels (ad libitum or restrictions of 70 or 80% of ad libitum intake). Animals were distributed in a 3×3 factorial arrangement, with 5 repetitions. The LEA showed: positive correlation with empty body weight, fasting body weight, meat, protein, ether extract and water (p &lt; 0.01), for all sex classes; with bones for intact males and females (p &lt; 0.01); with ash content for intact males and a moderate correlation for castrated males (p &lt; 0.01). The neck was correlated with empty body weight, fasting body weight, meat, protein, ether extract, water and energy in all sex classes (p &lt; 0.01); and moderate correlation with bone (r=0.58) and ash (r=0.67) for intact males. Intact males showed higher R² values in their prediction equations in relation to the other sex classes.

Pasture shooting and mobile slaughterhouses from a consumer's point of view: alternative slaughter methods and the meat paradox

PurposeThe purpose of this study is to investigate consumers' attitudes towards alternative slaughter methods (ASMs). ASMs present more animal-friendly and stress-free slaughter practices. However, these practices are not yet widespread due to strict regulations, high labor efforts and costs. Therefore, the market for meat products from ASMs is still small, and less is known about consumers' awareness, assessment and willingness to pay (WTP) for these products.Design/methodology/approachThis study aims to close the research gap using a standardized and representative online survey among 1,604 German participants. To identify target groups for these kinds of meat products, a factor and cluster analysis was conducted.FindingsThe results show that ASMs are not widely known among consumers. Overall, participants evaluated ASMs positively, but about 1/3 of the participants stated to also have concerns related more to hygiene than to animal welfare issues. The cluster analysis reveals two out of four clusters found that are interested in ASMs. These clusters are characterized by high trust in small butcheries and organic meat consumption.Originality/valueThe slaughtering sector has hardly been examined from an economic point of view in the animal welfare debate so far. This study identifies potential target groups for products originating from ASMs based on possible consumption drivers and barriers. Therewith, products from particular animal welfare friendly slaughter methods can be promoted purposefully to suitable target groups.

Effects of different starch structures on energy metabolism in pigs

BackgroundStarch is a major component of carbohydrates and a major energy source for monogastric animals. Starch is composed of amylose and amylopectin and has different physiological functions due to its different structure. It has been shown that the energy supply efficiency of amylose is lower than that of amylopectin. However, there are few studies on the effect of starch structure on the available energy of pigs. The purpose of this study was to measure the effect of different structures of starch in the diet on the net energy (NE) of pigs using a comparative slaughter method and to establish a prediction equation to estimate the NE of starch with different structures. Fifty-six barrows (initial BW 10.18 ± 0.11 kg) were used, and they were housed and fed individually. Pigs were divided into 7 treatments, with 8 replicates for each treatment and 1 pig for each replicate. One of the treatments was randomly selected as the initial slaughter group (ISG). Pigs in the remaining treatments were assigned to 6 diets, fed with basic diet and semi-pure diets with amylose/amylopectin ratio (AR) of 3.09, 1.47, 0.25, 0.15 and 0.12, respectively. The experiment lasted for 28 d.ResultsResults showed that compared with the high amylose (AM) groups (AR 3.09 and 1.47), the high amylopectin (AP) group (AR 0.15) significantly increased the final BW, average daily weight gain and average daily feed intake of pigs (P < 0.05), but the F:G of the AM group was lower (P < 0.01). In addition, AR 0.15 and 0.12 groups have higher (P < 0.01) nutrient digestibility of dry matter, crude protein, gross energy and crude ash. Meanwhile, compared with other groups, AR 0.15 group has a higher (P < 0.05) NE intake and energy retention (RE). The regressive equation for predicting with starch structures was established as RE = 1,235.243 − 48.298AM/AP (R2 = 0.657, P = 0.05).ConclusionsIn conclusion, NE intake and RE of pigs augmented with the increase of dietary amylopectin content, indicating that diets high in amylopectin were more conducive to promoting the growth of pigs in the late conservation period.

Field Based Assessment of Clinical Signs of Irreversible Loss of Consciousness and Death Confirmed by Brain Destruction in Juvenile American Alligators (Alligator mississippiensis) After Penetrating Captive Bolt Stunning or Electrostunning with Probe Pithing

ABSTRACT To determine the humane use of slaughter methods we examined the clinical signs of life in 61 American alligators harvested on-farm using one of three methods: (i) captive bolt and spinal cord severance; (ii) electrostunning, spinal cord severance and pithing; and (iii) spinal cord severance and pithing. Loss of consciousness and the six clinical signs of life that can be used on-farm were assessed for evidence of irreversible unconsciousness and death at Time 0, 0.5, 1, 2, 5, 10, 20, and 30 min post slaughter. The brains of alligators from each slaughter method were removed to assess brain tissue disruption. A combination of loss of blink reflex, pupillary light response, jaw tone and respiration are a reliable on-farm tool for determining death. Heartbeat and withdrawal reflex persisted. Captive bolt and electrostunning methods were effective in immediately producing loss of response consistent with irreversible unconsciousness, subsequent death and destruction of neural tissue integrity in the mid and hind brain. They are therefore humane forms of slaughter in American alligators.