Farm to abattoir conditions, animal factors and their subsequent effects on cattle behavioural responses and beef quality - A review

Effect of transportation distance and lairage time on selected behaviors and carcass parameters in zebu cattle-a study using the animal focal sampling method

The objective of this study was to evaluate the effect of the transport distance and lairage time on behavioral indicators of zebu beef cattle in the resting pen of a slaughterhouse using the focal animal technique. Eight lots of male zebu cattle, Nelore, aged approximately 4 years old, weighing on average 500 ± 28.5 kg-1, from different municipalities, transported by land, were evaluated. The lots were grouped into two categories: short distance (> 500 km) and long distance (> 500 km). Five focal animals per evaluated lot were used in each cycle of behavior observation, randomly chosen, and visually identified. The animal focal sampling method was used, with instantaneous recording, every 5 min per animal/h. A video camera was used and placed at a fixed point in the corral. After slaughtering, bruises and carcass pH were evaluated. The respiratory rate (RR) was measured in two moments, 30 min after unloading (RR_I) and 1 h before slaughtering (RR_F); behavioral data were divided into four lairage periods (1st, 2nd, 3rd, and 4th) equally and evaluated as repeated measures over time. The lairage time lowered the behaviors of headbutting (NCHBs), pushing (PsH), mounting (MT), and chasing away (CA), (p = 0.0001), and these behaviors were more evident in animals transported for short distances in the initial resting times, decreasing as they remained in the resting pen. There was effect of distance on the initial and final pH of the carcass, being greater in the short distance (p = 0.047). There was no effect of distance or lairage time on initial or final RR (p > 0.05). In addition, animals transported over long distances showed less carcass injuries, which were observed during post mortem inspection. It is concluded that animals transported over short distances present a greater number of agonistic behaviors, such as NCHBs, MT, PsH, and CA, predisposing to higher rates of bruising during lairage and more accentuated changes in the final pH of the meat.

Towards the use of on-farm slaughterhouse

Slaughter on the farm can address the concerns of farmers by meeting the needs of short distribution channels while better preserving animal welfare and meat quality. It can support conventional slaughter, by compensating for the significant decrease in the number of slaughterhouses in recent decades. The review describes first the different stages of slaughter and their possible impacts on animals' stress, welfare and consequences on their meat quality. The second part takes stock of recent thinking on the subject of slaughter and the regulation and technological advances that have led to the development of mobile slaughter units. A non-exhaustive list of mobile slaughter units currently in use in different countries is presented. Although these units can only absorb a small percentage of the total amounts of animals slaughtered, they are a welcome alternative to current slaughter practices for certain types of production and distribution, provided that the animal welfare and all aspects of meat quality are garanteed.

Animal welfare and effects of per-female stress on male and cattle reproduction—A review

Thermal stress causes severe effects on the wellbeing and reproduction of cattle, including changes in oogenesis and spermatogenesis, generating great concerns, which last for decades. In cattle, the occurrence of thermal stress is associated with a reduction in the production of spermatozoids and ovarian follicles, in addition to the increase of major and minor defects in gametes or in their intermediate stages. In bovine females able to reproduce, a reduction in the rate of estrus manifestation and an increase in embryonic mortality has been observed. Therefore, keeping animals on good welfare conditions, with water supply and in shaded areas can favor the improvement of different reproductive parameters. For all this, the present study aimed to gather, synthesize and argue recent studies related to animal welfare, focusing on the effects of thermal stress on the reproduction of cattle, aiming to support possible strategies to mitigate the harmful effects of thermal stress in this species.

Pre-slaughter, slaughter and post-slaughter practices of slaughterhouse workers in Southeast, Nigeria: Animal welfare, meat quality, food safety and public health implications

BACKGROUND

Pre-slaughter stress or the welfare condition of food-producing animals (FPAs) and the slaughter practices of slaughterhouse workers (SHWs) are critically important for the safety and quality of meats processed in slaughterhouses (SHs). Consequently, this study determined the pre-slaughter, slaughter, and post-slaughter (PSP) practices of SHWsin four SHs in Southeast, Nigeria; and discussed the impacts on meat quality and safety.

METHODS

The PSP practices were determined by observation method. Additionally, a structured and validated closed-ended questionnaire was used to determine the knowledge of the SHWs on: the effects of poor welfare (preslaughter stress) on the quality and safety of meats produced, carcass/meat processing practices and modes of transmission of meat-borne zoonotic pathogens during carcass/meat processing. Finally, a systematic post-mortem inspection (PMI) was conducted on cattle, pigs and goats slaughtered, and economic losses accruable from condemned carcasses/meats were estimated.

RESULTS

Food-producing animals were transported to the SHs or held in the lairage under inhumane conditions. A pig being conveyed to one of the SHs was seen gasping for air, as it was firmly tied on motorbike at the thoracic and abdominal regions. Fatigued cattle were forcefully dragged on the ground from the lairage to the killing floor. Cattle for slaughter were restrained, held in lateral recumbency and left groaning, due to extreme discomfort, for about one hour before slaughter. Stunning was not performed. Singed pig carcasses were dragged on the ground to the washing point. Although more than 50% of the respondents knew the modes of transmission of meat-borne zoonotic pathogens during meat processing, 71.3% of the SHWs processed carcasses on bare floor, 52.2% used same bowl of water to wash multiple carcasses while 72% did not wear personal protective equipment during meat/carcass processing. Processed meats were transported to meat shops in an unsanitary conditions, using open vans and tricycles. During the PMI, diseased carcasses/meats/organs were detected in 5.7% (83/1452), 2.1% (21/1006) and 0.8% (7/924) of the cattle, pig and goat carcasses inspected, respectively. Gross lesions pathognomonic of bovine tuberculosis, contagious bovine pleuro-pneumonia, fascioliasis and porcine cysticercosis were detected. Consequently, 391,089.2 kg of diseased meat/organs valued at 978 million Naira (235, 030 USD) were condemned. There were significant associations (p < 0.05) between educational level and the use of personal protective equipment (PPE) during slaughterhouse operations and knowledge that FPAs can harbour zoonotic pathogens (p = < 0.001) transmissible during carcass processing. Similarly, significant association was observed between working experience and use of PPE; and between geographical location of the respondents and knowledge that zoonotic pathogens in animals are transmissible during carcass processing or via the food chain.

CONCLUSION

The findings show that slaughter practices of SHWs have detrimental impacts on the quality and safety of meats processed for human consumption in Southeast, Nigeria. These findings underscore the need to: improve the welfare condition of slaughter-animals, mechanise abattoir operations, train and retrain the SHWs on hygienic carcass/meat processing practices. There is a need to adopt strict enforcement of food safety laws to promote meat quality, food safety and consequently promote the health of the public.

Investigating the impact of pre-slaughter management factors on indicators of fed beef cattle welfare – a scoping review

Introduction

The impact of pre-slaughter management practices on fed beef cattle welfare is a multifaceted and well researched subject matter. Factors such as transportation, handling, lairage time and several animal characteristics can directly impact the cattle’s behavior, mobility, blood lactate and cortisol levels, likelihood of injury and ultimately overall cattle welfare. Animal welfare continues to grow as a critical component of slaughter in the fed beef industry, yet a formal review of related research does not exist.

Methods

A scoping review was performed in order to (1) catalog pre-slaughter management factors that impact fed beef cattle welfare at the time of slaughter, (2) identify indicators used to evaluate the impact of pre-slaughter management on fed beef cattle welfare at slaughter, and (3) gain further understanding of the relationship between pre-slaughter management factors and fed beef cattle welfare outcome indicators at slaughter. Three data bases were ultimately searched: PubMed, CAB Abstracts, and Web of Science. The concepts used in the database searches were the population of interest (i.e., fed beef cattle), the location in the supply chain, preslaughter management factors, and welfare outcomes.

Results

A total of 69 studies were included in final analysis for this review, including studies from six geographic regions around the globe. Studies involving alternative slaughter methods (e.g., religious stunning or mobile slaughter) were not included in the formal analysis of this review, but still merited an in-depth discussion within this paper. After reviewing the studies, a total of 37 pre-slaughter factors and 69 indicators of welfare were measured throughout. Pre-slaughter management factors were then categorized by: animal characteristics; environmental characteristics; handling; lairage; transportation; and water/feed. Outcomeindicators of welfare were categorized into: behaviors; health, injury and disease; physiological; and stunning and insensibility.

Discussion

Pre-slaughter factors relating to transportation and handling, and welfare outcomes measured by behaviors and physiology were of the most researched throughout the studies.The results of this review offer a catalogue of commonly researched factors and indicators of welfare measured during the pre-slaughter phase, as well ast he relationships between them. This review also offers further substantial evidence that a multitude of events in the pre-slaughter phase affect fed beef cattle welfare and a collection of highly applicable welfare indicators to expedite further research on the effects of pre-slaughter factors and the application of improved practices.

Multi-omic data integration for the study of production, carcass, and meat quality traits in Nellore cattle

Data integration using hierarchical analysis based on the central dogma or common pathway enrichment analysis may not reveal non-obvious relationships among omic data. Here, we applied factor analysis (FA) and Bayesian network (BN) modeling to integrate different omic data and complex traits by latent variables (production, carcass, and meat quality traits). A total of 14 latent variables were identified: five for phenotype, three for miRNA, four for protein, and two for mRNA data. Pearson correlation coefficients showed negative correlations between latent variables miRNA 1 (mirna1) and miRNA 2 (mirna2) (−0.47), ribeye area (REA) and protein 4 (prot4) (−0.33), REA and protein 2 (prot2) (−0.3), carcass and prot4 (−0.31), carcass and prot2 (−0.28), and backfat thickness (BFT) and miRNA 3 (mirna3) (−0.25). Positive correlations were observed among the four protein factors (0.45–0.83): between meat quality and fat content (0.71), fat content and carcass (0.74), fat content and REA (0.76), and REA and carcass (0.99). BN presented arcs from the carcass, meat quality, prot2, and prot4 latent variables to REA; from meat quality, REA, mirna2, and gene expression mRNA1 to fat content; from protein 1 (prot1) and mirna2 to protein 5 (prot5); and from prot5 and carcass to prot2. The relations of protein latent variables suggest new hypotheses about the impact of these proteins on REA. The network also showed relationships among miRNAs and nebulin proteins. REA seems to be the central node in the network, influencing carcass, prot2, prot4, mRNA1, and meat quality, suggesting that REA is a good indicator of meat quality. The connection among miRNA latent variables, BFT, and fat content relates to the influence of miRNAs on lipid metabolism. The relationship between mirna1 and prot5 composed of isoforms of nebulin needs further investigation. The FA identified latent variables, decreasing the dimensionality and complexity of the data. The BN was capable of generating interrelationships among latent variables from different types of data, allowing the integration of omics and complex traits and identifying conditional independencies. Our framework based on FA and BN is capable of generating new hypotheses for molecular research, by integrating different types of data and exploring non-obvious relationships.

Beef Consumers Behaviour and Preferences—The Case of Portugal

Meat consumption is estimated to increase worldwide, mostly because of the increase in population. Further, this increase in meat consumption will ultimately affect the environment and aggravate climate change. Herein, consumers’ behaviour was studied to understand if consumers would consider a change in their dietary habits by choosing beef from the Portuguese autochthonous bovine breed or even reducing their meat intake for environmental reasons. In 2021, a survey was conducted online and in some food sales outlets in Portugal. Therefore, data collected from the 491 participants were analysed with the aim of assessing the Portuguese consumer behaviour and preferences on beef. Firstly, we conducted a descriptive analysis. Then, factor analysis was performed by principal component analysis. Finally, by cluster analysis, we attempted to identify a group of consumers with different behaviours into specific categories. Although it was not possible to segregate consumers into different categories, most of the respondents agree that meat consumption harms the environment; however, just 30.6% are willing to reduce meat consumption due to environmental reasons. As for the concerns for animal welfare, respondents between the age of 23 and 49 years seem to have a greater concern towards animal welfare. To value autochthonous bovine Jarmelista meat, it is fundamental to implement a concerted communication between suppliers and producers to value Jarmelista beef. Furthermore, it is also important that regional governmental institutions support local producers not only for financial support but also to create strategies to protect the breed from extinction.

Slaughter Conditions and Slaughtering of Pregnant Cows in Southeast Nigeria: Implications to Meat Quality, Food Safety and Security

The increase in the slaughter of pregnant cows (SPCs) for meat (except as may be approved by veterinarians on health grounds to salvage the animal) is unethical. SPCs for meat is also counterproductive, detrimental to food security, and may enhance zoonotic disease transmission. In this context, therefore, this current study examined slaughter conditions and the slaughtering of pregnant cows, and the implications for meat quality, food safety, and food security in Southeast Nigeria. The direct observational method was employed to examine the slaughterhouse activities, from when the cattle arrived at the lairage to the post-slaughter stage. A pre-tested and validated closed-ended-questionnaire was used to elicit information on causes of the SPCs and the method of disposal of eviscerated foetuses. Pregnancy status of cows slaughtered was determined by palpation followed by visual examination of the eviscerated and longitudinal incised uteri. The study lasted for six months during which 851 cows out of 1931 slaughtered cattle were surveyed. Assessment/decision-making protocol of slaughterhouse conditions, welfare conditions of slaughter-cattle, reasons for sale or slaughter of pregnant cows, distribution of pregnant cows slaughtered, method of disposal of eviscerated foetuses, and estimated economic losses of SPCs were delineated. Of the 851 cows examined, 17.4% (148/851) were pregnant while 43.2% (64/148) of the total foetuses recovered were in their third trimester. Major reasons adduced for SPCs by proportion of involved respondents were: ignorance of the animals' pregnancy status (69.7%, 83/119), high demand for beef (61.3%, 73/119), preference for large-sized cattle (47.9%, 57/119), economic hardship (52.1%, 62/119) and diseases conditions (42.9%. 51/119). The conduct of SPCs for meat would not be profitable. This is because within six months, an estimated loss of about 44,000 kg of beef, equivalent to ₦ 70.1 million or $186,400 would be associated with SPCs and the consequential foetal wastages. If losses were to be replicated nationwide across slaughterhouses, 4.3 tons of beef estimated at ₦ 8.6 billion or $23 million would be wasted. Improving slaughter conditions and the welfare of slaughter-cattle in Nigerian slaughterhouses through advocacy, training of slaughterhouse workers, and strict implementation of laws promoting humane slaughter practices is imperative. Preventing SPCs for meat and inhumane slaughter practices at the slaughterhouse would enhance the welfare needs of slaughter cattle, grow the national herd size, and improve meat safety as well as food security.

Sire Effects on Carcass of Beef-Cross-Dairy Cattle: A Case Study in New Zealand

Simple Summary

Cattle born in the dairy industry are a very important source of beef. This study evaluated the carcasses of cattle born to dairy cows and sired by a range of Angus and Hereford sires. Sire affected most carcass traits of their progeny, particularly size and fat traits. The heaviest sire had 46 kg greater carcass weight compared with the lightest sire, equivalent to NZ$266 greater value per progeny. Carcass fat traits (rib fat depth and marble scores) were the most variable among sires, indicating possibility of selection. Thus, using beef-breed sires chosen for greater carcass weight has the potential to increase the meat production of cattle born on dairy farms, while maintaining adequate fat levels and carcass quality to receive optimum payment.

Abstract

There is interest in increasing the carcass value of surplus calves born in the dairy industry that are reared for beef production in New Zealand. This experiment evaluated the carcass of Angus and Hereford sires via progeny testing of beef-cross-dairy offspring grown on hill country pasture. Weight and carcass traits were analyzed from 1015 animals and 1000 carcasses of 73 sires. The mean of the progeny group means was 567 kg for live weight at slaughter, 277 kg for carcass weight, 48.9% for dressing-out, 240.3 cm for carcass length, 73.6 cm² for eye muscle area, 7.4 mm for rib fat depth, 0.91 for marble score, 3.05 for fat color score, 3.01 for meat color score, and 5.62 for ultimate pH. Sire affected (p < 0.05) carcass size and fat traits, but not fat color, meat color, or ultimate pH (p > 0.05). There was a 46 kg increase in carcass weight between the best and worst sires tested. Carcass fat traits were the most variable among sires. The use of genetically superior beef-breed sires over dairy-breed cows has the potential to increase carcass weights from surplus calves born in the dairy industry, while maintaining adequate fat levels and carcass quality.

Effect of pre-slaughter fasting duration on physiology, carcass and meat quality in beef cattle finished on pastures or feedlot

Pre-slaughter fasting duration affect blood parameters related to stress and metabolism, decrease live and carcass weights and impact beef quality of cattle. In three experiments, 1100 steers and heifers, finished on feedlot or on pasture, were evaluated to assess the influence of the site and duration of fasting before slaughter on physiological, carcass and meat quality traits. Cattle were allocated to one of two fasting duration - long (23-29 h) or short (2-6 h) - and to one of two sites of fasting- farm or abattoir. All animals had access to water ad libitum until slaughter, except during transportation. Cattle were assigned to two (long fasting on abattoir/normal lairage time, short fasting on farm/minimal lairage time) or three (long fasting on abattoir/normal lairage time, short fasting on farm/minimal lairage time, long fasting on farm/minimal lairage time) treatments. Seventeen slaughters were considered in a randomized complete block design. There was no effect of the site of fasting on any variable. Cattle with short fasting duration had higher carcass weights and water consumption than those under long fasting duration. Haematocrit, globulin, total protein, and lactate dehydrogenase at the time of slaughter increased with fasting duration. There was no effect of the duration of fasting on blood ions, meat quality traits, urine pH, liver weight and volume, and skin dry matter. A reduction in the fasting duration returned to farmers and abattoirs 1.2% additional kilograms of carcass, suggesting an improvement in animal welfare according to a better hydration level of cattle at the time of slaughter.

Enhanced Antibacterial Activity of Silver Nanoparticles Combined with Hydrogen Peroxide Against Multidrug-Resistant Pathogens Isolated from Dairy Farms and Beef Slaughterhouses in Egypt

Purpose

The last few decades have witnessed a rapid and global increase in multidrug-resistant bacteria (MDR) emergence.

Methods

The aim of the current study is to isolate the most common MDR bacteria from dairy farms and beef slaughterhouses followed by evaluation of their antimicrobial resistance pattern and assessment of the antibacterial activity of AgNPs-H₂O₂ as an alternative to conventional antibiotics. In this regard, 200 samples were collected from two dairy farms and one beef slaughterhouse located in Dakhliya Governorate, Egypt.

Results

Interestingly, out of 120 collected samples from dairy farms, the prevalence of the isolated strains was 26.7, 23.3, 21.7, 16.7, and 11.7% for S. typhimurium, E. coli O157:H7, L. monocytogenes, K. pneumoniae and P. aeruginosa, respectively. Meanwhile, the overall prevalence was 30, 25, 22.5, 17.5, and 5% for E. coli O157:H7, L. monocytogenes, S. typhimurium, P. aeruginosa, and K. pneumoniae, respectively, for the 80 samples collected from a beef slaughterhouse. The antimicrobial susceptibility pattern elucidated that all isolated strains exhibited resistance to at least four of the tested antimicrobials, with multiple-antibiotic resistance index values (MAR) ranging between 0.44 and 0.88. Furthermore, the commercial AgNPs-H₂O₂ product was characterized by transmission electron microscopy (TEM) and zeta potential that showed spherical particles with a surface charge of -0.192 mV. The antimicrobial activity of synergized nano-silver (AgNP) with H₂O₂ product toward MDR strains was assessed via measuring minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and time-kill curve.

Conclusion

The present data report high prevalence rates of MDR pathogens in dairy farms and abattoirs. More importantly, AgNPs-H₂O₂ exerted broad-spectrum bactericidal activity toward MDR bacterial strains, suggesting their promising usage as safe, ecofriendly, cost-effective antibacterial agents. To our knowledge, this study is a pioneer in investigating the potential alternative antimicrobial role of silver nanoparticles for control of multiple drug-resistant pathogens in Egypt.

Genetic Architecture of Carcass and Meat Quality Traits in Montana Tropical® Composite Beef Cattle

The Montana Tropical^® Composite is a recently developed beef cattle population that is rapidly expanding in Brazil and other tropical countries. This is mainly due to its improved meat quality and adaptation to tropical climate conditions compared to Zebu and Taurine cattle breeds, respectively. This study aimed to investigate the genetic architecture of ultrasound-based carcass and meat quality traits in Montana Tropical^® Composite beef cattle. Therefore, we estimated variance components and genetic parameters and performed genome-wide association studies using the weighted single-step Genomic Best Linear Unbiased Prediction (GBLUP) approach. A pedigree dataset containing 28,480 animals was used, in which 1,436 were genotyped using a moderate-density Single Nucleotide Polymorphism panel (30K; 30,105 SNPs). A total of 9,358, 5,768, 7,996, and 1,972 phenotypic records for the traits Longissimus muscle area (LMA), backfat thickness (BFT), rump fat thickness (RFT), and for marbling score (MARB), respectively, were used for the analyses. Moderate to high heritability estimates were obtained and ranged from 0.16 ± 0.03 (RFT) to 0.33 ± 0.05 (MARB). A high genetic correlation was observed between BFT and RFT (0.97 ± 0.02), suggesting that a similar set of genes affects both traits. The most relevant genomic regions associated with LMA, BFT, RFT, and MARB were found on BTA10 (5.4–5.8 Mb), BTA27 (25.2–25.5 Mb), BTA18 (60.6–61.0 Mb), and BTA21 (14.8–15.4 Mb). Two overlapping genomic regions were identified for RFT and MARB (BTA13:47.9–48.1 Mb) and for BFT and RFT (BTA13:61.5–62.3 Mb). Candidate genes identified in this study, including PLAG1, LYN, WWOX, and PLAGL2, were previously reported to be associated with growth, stature, skeletal muscle growth, fat thickness, and fatty acid composition. Our results indicate that ultrasound-based carcass and meat quality traits in the Montana Tropical^® Composite beef cattle are heritable, and therefore, can be improved through selective breeding. In addition, various novel and already known genomic regions related to these traits were identified, which contribute to a better understanding of the underlying genetic background of LMA, BFT, RFT, and MARB in the Montana Tropical Composite population.

Evaluation of rumen temperature as a novel indicator of meat quality: Rumen temperature and haematological indicators of stress during the pre-slaughter period as predictors of instrumental meat quality in bulls

The use of new technologies such as rumen temperature boluses, together with the collective assessment of an animal stress responses may have the potential to act as an indicator of meat quality. Therefore, the objective of this study was to evaluate rumen temperature as a novel indicator of meat quality, by investigating its relationship with welfare measures and instrumental meat quality. The study involved 42 Holstein bulls (15.8 ± 0.08 months of age), which were transported 42 km to a commercial abattoir. Mean rumen temperature rose by 0.511 °C (P < .001) during the pre-slaughter phase; peaking during lairage. In addition, cortisol, creatine kinase (CK) and lactate dehydrogenase (LDH) were significantly (P < .001) elevated at slaughter. Bulls with a greater rumen temperature during the pre-slaughter phase produced meat with significantly higher pH_ult. Pre-slaughter rumen temperature was positively associated with slaughter CK, slaughter cortisol, pH_ult, L* and a*. Thus, rumen temperature demonstrates the potential to be used both as a novel welfare indicator and predictor of meat quality.

An outlook on livestock welfare conditions in African communities - A review

A significant proportion of the African continent is conducive for animal agricultural production, due to its historical experience and available resources to accommodate and nurture various indigenous and exotic animal species and breeds. With food security being a global challenge, animal products can play an important role as nutrient dense food sources in human diets, particularly in Africa. However, this does not seem to reach its full potential in practice, due to numerous reasons that have not been adequately addressed. Animal welfare reservations can be highlighted as one of the major contributing factors to the curbed progress. The consequences have been scientifically proven to affect product quality and market access. However, in the African community, the concept of animal welfare has not been fully embraced. While there are international animal welfare standards in the developed world, there are inherent factors that hinder adoption of such initiatives in most developing regions, particularly among communal farmers. These include cultural norms and practices, social ranking, socio-economic status, available resources, information dissemination and monitoring tools. Therefore, there is need to harmonize what is internationally required and what is feasible to accommodate global variability. The protocols followed to ensure and evaluate farm animal welfare require regular investigation, innovation and a sustainable approach to enhance animal productivity, efficiency and product quality. Additionally, investing in animal wellbeing and health, as well as empowering communities with significant knowledge, has a potential to improve African livelihoods and contribute to food security. This review seeks to highlight the concept of animal welfare in relation to livestock and food production in African conditions.

An evaluation of environmental, intrinsic and pre- and post-slaughter risk factors associated to dark-cutting beef in a Federal Inspected Type slaughter plant

The objective was to determine the risk factors associated to dark-cutting in bovine carcasses. The study was conducted at a Federal Inspection abattoir located in northeastern Mexico. A random sample of 394 animals at slaughter was used. A total of 26 explanatory variables were evaluated; the analysis included environmental, animal-specific, and management factors both at pre- and post- slaughter periods. Only four variables were statistically significant within the final logistic regression model (P < .001). The frequency of dark-cutting carcasses was 13.45%. Lairage time was directly proportional to the percentage of risk for dark-cutting beef. Improper desensitization also increased the frequency of carcasses with this anomaly. Backfat thickness and the 24-h pH differential of the carcasses were inversely proportional to the risk for dark-cutting beef. An interesting finding was that risk factors for DFD meat are present in all stages of the slaughter process and thus to effectively address this problem an integral evaluation is needed throughout the slaughter process.

Pre-slaughter cattle welfare indicators for use in commercial abattoirs with voluntary monitoring systems: A systematic review

Animal welfare has become an important subject of public, economic and political concern, leading to the need to validate indicators that are feasible to use at abattoirs. A systematic review was carried out, which identified 72 cattle welfare indicators (CWI) that were classified into four categories (physiological, morphometric, behavioral and meat quality). Their validity and feasibility for use in abattoirs were evaluated as potential measures of cattle welfare during transportation to the abattoir and at the abattoir itself. Several highly valid indicators were identified that are useful to assess welfare at abattoirs, including body condition score, human-animal interactions, vocalizations, falling, carcass bruising, and meat pH. In addition, some intermediate valid indicators are useful and should be investigated further. Information along the food chain could be used systematically to provide a basis for a more-risk-based meat inspection. An integrated system based on the use of key indicators defined for each inspection step with the setting of alarm thresholds could be implemented.