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

Enhancing sustainability through resource efficiency in beef production systems using a sliding time window-based approach and frame scores

The food needs of the increasing global population, inefficiencies in supply chains, customer expectations and environmental concerns are the challenges to meeting resource-intensive protein needs sustainably. Collectively, this increases the need to enhance sustainability in the beef sector. This study proposes a sliding time-window-based multi-period livestock production model using mixed-integer linear programming (MILP) to simultaneously balance economic and environmental losses. It identifies the optimal finishing time using frame score (FS) and feed conversion ratio (FCR), targeting flexibility by allowing variable growth periods to reduce food/nutritional losses while meeting the variability in demands with minimum inventory levels. Furthermore, sequencing and assigning animals to facilities with optimum separation time is applied to avoid bad handling of animals and ensure quality meat with hygienic standards for longer shelf life. The system boundary of the proposed model includes beef farms and processing facilities. Compared to the recently proposed batch processing models over seven months with a herd size of 1980 animals, the findings reduce the average forage needed by ∼126.90 kips and methane emissions by ∼2560 kg, with a significant benefit in terms of the live animals' weight gain by ∼10,276 lbs.

Microbial spoilage mechanisms of vacuum-packed lamb meat: A review

Lamb meat is an important export commodity, however chilled vacuum-packed (VP) lamb has approximately half the shelf-life of beef under the same storage conditions. This makes the industry more vulnerable to financial losses due to long shipping times and unexpected spoilage. Understanding the spoilage mechanisms of chilled VP lamb in relation to VP beef is important for developing effective strategies to extend the shelf-life of lamb. This review has discussed various key factors (i.e., pH, fat, and presence of bone) that have effects on microbial spoilage of VP lamb contributing to its shorter shelf-life relative to VP beef. A range of bacterial organisms and their metabolisms in relevance to lamb spoilage are also discussed. The data gap in the literature regarding the potential mechanisms of spoilage in VP red meat is highlighted. This review has provided the current understanding of key factors affecting the shelf-life of VP lamb relative to VP beef. It has also identified key areas of research to further understand the spoilage mechanisms of VP lamb. These include investigating the potential influence of fat and bone (including bone marrow) on the shelf-life, as well as assessing changes in the meat metabolome as the spoilage microbial community is developing using an integrated approach. Such new knowledge would aid the development of effective approaches to extend the shelf-life of VP lamb.

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.

Differential regulation of intramuscular fat and abdominal fat deposition in chickens

Background

Chicken intramuscular fat (IMF) content is closely related to meat quality and performance, such as tenderness and flavor. Abdominal fat (AF) in chickens is one of the main waste products at slaughter. Excessive AF reduces feed efficiency and carcass quality.

Results

To analyze the differential deposition of IMF and AF in chickens, gene expression profiles in the breast muscle (BM) and AF tissues of 18 animals were analyzed by differential expression analysis and weighted co-expression network analysis. The results showed that IMF deposition in BM was associated with pyruvate and citric acid metabolism through GAPDH, LDHA, GPX1, GBE1, and other genes. In contrast, AF deposition was related to acetyl CoA and glycerol metabolism through FABP1, ELOVL6, SCD, ADIPOQ, and other genes. Carbohydrate metabolism plays an essential role in IMF deposition, and fatty acid and glycerol metabolism regulate AF deposition.

Conclusion

This study elucidated the molecular mechanism governing IMF and AF deposition through crucial genes and signaling pathways and provided a theoretical basis for producing high-quality broilers.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12864-022-08538-0.

Small RNA-Seq Analysis Reveals miRNA Expression of Short Distance Transportation Stress in Beef Cattle Blood

Simple Summary

In this study, three miRNA modules were identified in a cattle short-distance transportation stress model, and the turquoise module showed key miRNA sets according to their correlation with hub genes. Further, hub miRNAs were identified based on their targeting relationship with hub genes in our previous study. This finding provides the potential utility for predicting and treatment of short-distance transportation stress in beef cattle.

Abstract

Transportation is a crucial phase in the beef cattle industry, and the annual losses caused by beef cattle transport stress are substantial. Because of its huge economic losses, such as lower growth rate and even death, long-distance transportation stress has attracted more attention from beef production practitioners because of its huge economic losses. Compared with the long-distance transportation stress, the short-distance transportation stress was ignored for the reason of no obvious symptoms in cattle. Our previous study showed that the disorder of B cell function could be a potential health risk after short-distance transportation. However, the transcriptome details of the changes in the cattle blood after short-distance transportation and the molecular mechanisms for the regulation of the developmental process are not clearly known. In this study, a total of 10 Qinchuan cattle were used to compare the molecular characteristics of blood before and after short-distance transportation. The miRNA-seq showed that 114 differentially expressed miRNAs (DEMs) were found (40 upregulated and 74 downregulated) between two groups before and after transportation. Furthermore, more than 90% of the miRNAs with counts of more than 10 were used to construct a co-expression network by weighted correlation network analysis (WGCNA), and four independent modules were identified. According to their relationship with 30 hub genes, the turquoise module was the key module in this study. The regulator network of hub genes and miRNAs in the turquoise module was constructed by miRNAs targeting genes predicting, and the miRNAs had targeting sites within hub genes that could be identified as hub-miRNAs. Further, it showed that CD40 and ITPKB had the same targeting miRNAs (miR-339a/b), and the newly discovered hub miRNAs filled the gaps in our previous study about the relationship between hub genes in short-distance transportation stress and provided the potential utility for predicting and treatment of short-distance transportation stress in beef cattle.

Effect of Finishing Diet and Lairage Time on Steers Welfare in Uruguay

Simple Summary

The transport and general handling of slaughter animals are associated with a series of events that cause stressful and unfavorable conditions that can compromise animal welfare. All these stressful events start at the farm and end with the death of the animal. In this experiment, we evaluated the effect of two finishing strategies and two contrasting lairage times through the combination of several indicators regarding productivity, physiology, behavior and postmortem variables. Individual temperaments and their impact on welfare and carcass quality were also considered. Animal welfare was not compromised in any diet during the finishing period. Individual temperament had a positive impact on the productivity and on all physiological indicators at different preslaughter stages. For that reason, we consider that it should be given paramount importance when talking about animal welfare. According to our results, with pasture-based animals, without fasting on the farm and after a short time of transportation (3.5 h), a longer preslaughter resting time (15 vs. 3 h) is desirable from the animal welfare perspective. Furthermore, our results suggest that this longer resting period, would also be more convenient from the carcass quality perspective.

Abstract

The objective of this experiment was to evaluate the effect of two different pasture-based finishing strategies and lairage time on steers welfare in Uruguayan conditions. Sixty Hereford (H) and Braford (B) steers were assigned to two different diets for finishing purposes: (D1) native pasture plus corn grain (1% of live weight) (H n = 15, B n = 15) and (D2) high-quality pasture (H n = 15, B n = 15). The average daily gain was registered every 14 days, and temperaments were individually assessed one week before slaughter by three individual tests: crush score, flight time and exit speed, building a multicriterial temperament index (TIndex). Animals were slaughtered the same day in two groups (50% from D1 and 50% from D2 in each group) after traveling for 3.5 h and staying 15 (long lairage) and 3 h (short lairage) in the lairage pens, respectively. The behaviors were observed during lairage, and physiological indicators were used to assess stress at the farm after transport, after lairage and at slaughter. Bruises incidence and final pH were registered at the abattoir as a means of assessing the overall animal welfare. Calmer animals had higher average daily gains with no differences either between diets or between breeds. Calmer animals also had a lower stress response during all preslaughter stages, regardless of the time in lairage. Transport did not imply psychological stress (cortisol) for any slaughter group, but physical stress was evident after transport in both groups through NEFA and CPK increases. Bruise incidences did not differ between lairage groups. The short lairage group did not have enough time to cope with the environment before slaughter, with the consequent deleterious effects on the carcass pH. Animals from the long lairage group had a higher metabolic response shown through NEFA values, but they had enough time to rest and recover overnight, reaching final pH values lower than 5.8, considered the upper limit of the normal range. According to this experiment, with pasture-based animals without fasting on the farm and after 3.5 h of transportation, a resting period of 15 h in lairage should be better than a 3-h one.