Slaughter Plant Research Articles

Problems with Congestive Heart Failure and Lameness That Have Increased in Grain-Fed Steers and Heifers

Grain-fed steers and heifers have increasing problems with both lameness and congestive heart failure. Congestive heart failure used to be limited to cattle raised at high altitudes. It is now occurring at much lower elevations. An inspection of hearts at the slaughter plant indicated that some groups of grain-fed steers and heifers had abnormally swollen hearts in 34% of the animals. Congestive heart failure may also increase death losses in the late stages of the feeding program. Lameness has also increased to 8% of grain-fed steers and heifers arriving at U.S. slaughter plants. Twenty years ago, observations by the author indicated that lameness in fed cattle arriving at the slaughter plant was almost zero. There has also been an increasing occurrence of abnormal hoof structure and poor leg conformation. Genetic selection for rapid growth and a large ribeye may be associated with the increase in both of these problems. Lameness and heart problems severely compromise animal welfare.

Ulcerative stomatitis associated with yellow bristle grass in New Zealand dairy cows

ABSTRACT Case history A line of 25 cull cows were all found to have ulcerative lesions of the tongue at post-mortem inspection in a New Zealand slaughter plant. A further 9 of 10 cows inspected at the farm of origin had similar oral lesions. There were no other clinical signs or indicators of ill-health observed at ante-mortem inspection in the abattoir or on the farm. The cows had been fed baleage for 3 weeks prior to slaughter, made from pasture in paddocks heavily contaminated with yellow bristle grass (Setaria pumila). Clinical findings There was extensive and deep transverse linear ulceration in the lingual fossa immediately rostral to the torus linguae. At histological examination, full-thickness ulceration of the stratified squamous epithelium was observed with a bed of disorganised collagenous tissue and extensive mixed inflammatory infiltrate extending into the sub-epithelial connective tissue and skeletal muscle. Barbed plant fragments were embedded in both the superficial and deeper areas of inflammation. Detailed examination of the baleage also found that yellow bristle grass seedheads were present. Diagnosis Based on the presence of barbed plant material in the tongue and yellow bristle grass seeds in the baleage, a diagnosis of ulcerative stomatitis associated with yellow bristle grass was made. Clinical relevance Clinicians should be aware of the potential for hay or baleage contaminated with yellow bristle grass to cause oral lesions in cattle.

Virome analyses of Amblyomma cajennense and Rhipicephalus microplus ticks collected in Colombia

Tick-borne viruses (TBV) have gained public health relevance in recent years due to the recognition of human-associated fatal cases and the increase in tick-borne disease and transmission. However, many tick species have not been studied for their potential to transmit pathogenic viruses, especially those found in Latin America. To gain better understanding of the tick virome, we conducted targeted amplification using broadly-reactive consensus-degenerate pan-viral targeting viruses from the genera Flavivirus, Bandavirus, Uukuvirus, and Orthonairovirus genus. Additionally, we conducted unbiased metagenomic analyses to investigate the presence of viral RNA sequences in Amblyomma cajennense, A. patinoi and Rhipicephalus microplus ticks collected from a horse slaughter plant in Medellín, Colombia. While no viral products were detected by PCR, results of the metagenomic analyses revealed the presence of viral genomes belonging to the genera Phlebovirus, Bandavirus, and Uukuvirus, including Lihan Tick Virus (LTV), which was previously reported in Rhipicephalus microplus from Colombia. Overall, the results emphasized the enormous utility of the next-generation sequencing in identifying virus genetic diversity presents in ticks and other species of vectors and reservoirs.

Benchmarking the United States bison meat industry: stakeholder perceptions, production parameters, and live animal factors affecting meat quality.

The objectives of this study were 1) to understand stakeholder perceptions regarding the bison industry, 2) to benchmark live animal characteristics and production parameters of the bison industry, and 3) to identify live animal factors related to animal welfare and their effect on specific quality characteristics of bison meat. A survey was conducted both online and in-person at the National Bison Association Winter Conference (2022). Descriptive statistics were performed on a total of 110 surveys. Most stakeholders (94%, n = 104) agreed that the industry should continue to grow, and the majority (99%, 108) agreed that animal welfare impacts meat quality. Facility design (80%, n = 88), animal handling (78%, 86), employee training (56%, 62), and transportation duration (56%, 62) were selected as the factors that affect animal welfare. More than half of the stakeholders selected flavor (67%, n = 74) as the most important quality attribute of bison meat. For the in-plant antemortem and postmortem parameters data was collected from three plants in the United States over the course of a year. A total of 2,284 bison (bulls: n = 1,101; cows: n = 199; heifers: n = 984) were included in the study. Antemortem measurements such as distance traveled, vocalization, prod use, mobility, and head bumps were measured, followed by postmortem measurements that included bruise score, live weight, dressing percentage, ribeye area, and instrumental color. Approximately 97% of bison (n = 2,213) had at least one bruise. The average distance traveled from producer to slaughter plant was (mean ± SD; 823 ± 583 km) and the average dressing percentage was (mean ± SD; 60.5 ± 3.3%). Average (mean ± SD) fat thickness and ribeye area were 1.4 ± 1.1cm and 62.6 ± 9.8cm2, respectively. Approximately 30% (n = 676) of the bison in this study head bumped between 1 and 5 times in the restraining chute or the single-file gate before being stunned. Linear regression indicated that differences in lean a* were associated with plant, number of head bumps in the chute, ribeye area, fat thickness, live weight, and sex class (P < 0.05). Logistic regression indicated that season, sex class, live weight, plant, and season were associated with differences (P < 0.05) in bruising. These results can be used as a baseline for current production parameters and serve as the foundation for future research to monitor improvement.

Comparison of differences in performance between pigs whose sires were identified using different selection strategies after experimental infection with PRRSV.

The objective of this study was to evaluate differences in the performance of offspring of boars selected with an index emphasizing resilience and boars selected based on a traditional index, emphasizing feed efficiency and carcass quality (traditional) index vs. a customized (resilience) index. The resilience index was identical to the traditional index, except that extra emphasis was placed on piglet vitality (increased by 66%), growth rate (decreased by 14%), and feed intake (increased substantially by 5,157%). Sows were mated to either boars selected based on the resilience index or boars selected on the traditional index. Weaned offspring were vaccinated for Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) and experimentally infected with PRRSV RFLP 1-7-4 four weeks later. Offspring were allocated to pens (n ~ 27 pigs/pen; n = 27 pens/group) by sire-selection group for a total of 1,458 pigs in 54 pens. The weight of each pen was recorded on 0, 42, and 110 d postinfection (DPI) and used to calculate average daily gain (ADG), average daily feed intake (ADFI), and feed conversion ratio (FCR). Mortalities were recorded from 0 to 110 DPI and necropsies were routinely performed to characterize pathogens present within the barn. Pigs classified as full value (i.e., >104kg and void of defects) were slaughtered and hot carcass weight (HCW), backfat, loin depth, and lean weight were obtained from the slaughter plant. Effects of progeny group on performance, carcass characteristics, and mortality rate were estimated with a mixed linear model. Differences between progeny groups in ADG (P > 0.27), HCW (P = 0.68), backfat (P = 0.13), or loin depth (P = 0.39), and mortality rate (P = 0.29) were not detected. From 0 to 42 DPI, offspring of boars selected based on the resilience index had higher ADFI (0.06kg/d, P = 0.01) and higher FCR (0.12, P = 0.01). In summary, results from this study do not support selection of boars for increased feed intake, piglet viability, and robustness in order to prevent losses caused by PRRSV, but selection response was only measured after one generation of male selection. The impact of multiple generations of selection, or the development of an index including traits derived from data collected under disease-challenged conditions should be explored. The data collected for this study are a valuable resource to explore additional genetic selection strategies for enhanced resilience to a multifactorial PRRS challenge.

PSVII-22 Effect of Trimming External Fat Before Cooking on Palatability and Calorie Content of Beef Ribeye Steaks

Abstract Consumer concerns about excess dietary fat have increased the practice of removing external fat from beef steaks prior to cooking. This practice, however, may be detrimental to meat eating quality. The objective of this study was to determine the effects of removing the external fat before cooking on the eating quality and calorie content of ribeye steaks. Twenty longissimus thoracis muscles with Canada AAA (n = 10) and AA (n = 10) quality grades (equivalent to USDA Choice and Select, respectively) were obtained from a federally inspected commercial slaughter plant, vacuum packaged and transported under refrigerated conditions to the Lacombe Research and Development Centre (Agriculture and Agri-Food Canada). After an average of 28 d of ageing, the muscles were removed from the vacuum packaging and fabricated into four 2.54-cm steaks. One-half of the steaks were trimmed to 0.635 cm of external fat (cap on). The remaining steaks were completely trimmed of external and seam (kernel) fats (cap off), and the longissimus and spinalis dorsi muscles were combined with butcher’s twine. Steaks were cooked on an electric grill to an endpoint temperature of 74 °C. Subsequently, descriptive sensory analyses were performed by a 10-member trained meat evaluation panel and calorie analyses were conducted. Results: Compared with muscles of AA steaks cooked with cap off, the AA steaks cooked with cap on had longissimus with greater initial and sustained juiciness (P &amp;lt; 0.01) and a tendency towards a smaller proportion of panelists detecting livery off-flavor (P = 0.058) and mealy texture (P = 0.071), and spinalis with a tendency towards fewer panelists detecting unidentified off-flavors (P = 0.096) and spongy texture (P = 0.096). When cooking the AAA steaks with cap on, the longissimus had a decreased frequency of panelists detecting ‘other’ off-flavors (i.e., burnt, rancid, barnyard, stale; P &amp;lt; 0.05) and mushy texture (P &amp;lt; 0.05) and tended to have less off-flavor intensities (P = 0.083), whereas the spinalis had greater beef flavor intensity and desirability (P &amp;lt; 0.05) and fewer panelists tending to detect ‘other’ off-flavors (i.e., burnt, fatty, oily, rancid; P = 0.052), compared with steaks cooked with cap off. The more pronounced flavor effects in the spinalis compared with the longissimus of AAA steaks cooked with cap on could be due to the spinalis having greater endpoint temperatures than the longissimus muscles, which probably caused more Maillard reactions and more efficient fat melting. Regardless of the quality grade and muscle type, cooking steaks with cap on did not increase the calorie content (P &amp;gt; 0.10). Overall, cooking ribeye steaks with external fat had positive effects on juiciness, flavor and texture without increasing the calorie content compared with steaks cooked without external fat. Educating consumers on the benefits of maintaining the external fat while cooking will improve the eating experience of Canadian beef.

Study of the transfer of Shiga toxin-producing Escherichia coli during the slaughter of cattle using molecular typing combined with epidemiologic data

Investigation on the distribution and biological characteristics of Shiga-toxin producing Escherichia coli (STEC) during beef processing is essential for in-plant critical control points and food safety risk assessment. Serogroups and subtypes of stx genes of STEC strains isolated from beef processing lines were first investigated. Identification to cross-contamination among different sampling sites was further conducted by combining multilocus sequence typing (MLST) with the previous distribution and characterization data. The PCR-positive rate for STEC in 435 samples from two slaughter plants in China was 14.3% and the isolation rate for the 62 PCR positive and the entire set of 435 samples were 26% and 3.68% respectively. The existence of serotype O157:H7 (33%) and serogroups O121 (42%) and O26 (21%) as well as the high detection rate of high pathogenic gene stx2a (68%) in these serogroups indicated potential risk to the safety of beef. Traceability analysis showed that hide plays a critical role in cross-contamination between feces, lairage pens and post-washing carcasses from a molecular perspective. Intervening measures revolves around de-hiding should be involved in the in-plant safety control policy according to the tracing analysis.

Longitudinal analysis of differences and similarities in antimicrobial resistance among commensal Escherichia coli isolated from market swine and sows at slaughter in the United States of America, 2013–2019

The emergence of antimicrobial resistance in swine enteric bacteria poses a significant public health challenge. Our study evaluated publicly available data collected by the National Antimicrobial Resistance Monitoring System for Enteric Bacteria (NARMS) between 2013 and 2019 at slaughter plants across the United States of America, focusing on commensal E. coli isolated from swine cecal contents originating from two distinct swine production systems: market hogs (n = 2090) and sows (n = 1147). In both production types, the highest pairwise correlations were detected among β-lactam antimicrobials, including resistance to amoxicillin-clavulanic acid, ceftriaxone, and cefoxitin, suggesting a co-selection for resistance. Compared to 2013, an increase in the rate of E. coli isolates that were resistant to β-lactam antimicrobials was higher in 2017, 2018, and 2019, and this increase was more pronounced in isolates obtained from market hogs. Differences in antimicrobial resistance between these two distinct swine production systems warrant production-type focused mitigation efforts.

A Successful Case of Implementation of Farm Animal Welfare Audits by Large Meat Buyers

Abstract For many years, the supply chain managers of large supermarkets and restaurant corporations have been conducting animal welfare audits of farms and slaughter plants. Some programs have been more effective than others. This case history describes the early implementation of a highly effective program for auditing animal welfare in slaughter plants. The lessons learned from the implementation of this program in 1999 are still relevant today. There were four major factors that made this welfare auditing program effective. They were: (1) corporate management became motivated to improve conditions in the slaughter plants after they visited plants that had severe animal welfare problems, (2) the welfare standards used to audit the beef and pork plants were simple and easy to understand. They provided clear guidance on conditions that would result in a failed audit, (3) more than one commercial company enforced the same standards at the numerous slaughter plants, and (4) there was an emphasis on repairing existing facilities and improving management instead of buying lots of expensive new equipment. There were only 3 plants out of 75 where expensive renovations were required. This case history will also discuss how veterinarians and management consultants can help food animal supply chain managers implement effective programs that will improve animal welfare. Practical commercial animal welfare assessments will need to be simpler than assessments used for research. Information © The Author 2023

Disasters, population trends, and their impact on the U.S. pork packing sector

In 2020, disruptions and risks from COVID-19 led to meatpacking plant shutdowns and reductions in total slaughter relative to 2019. Debate emerged surrounding the vulnerability of the packing industry and whether larger plants were more prone to reductions in slaughter compared to smaller plants. Using a novel panel dataset of 40 major U.S. hog slaughter plants, we estimate packers’ propensities to reduce production relative to their normal operational capacity, controlling for plant characteristics, local labor conditions, and severe weather events. We find larger plants are, on average, more likely to reduce daily slaughter and that an increase in plant physical capacity leads to an increase in the quantity reduced. However, we do not find a statistically significant relationship between plant capacity and shutdowns. We find strong evidence that factors indirectly limiting labor availability—the average number of COVID-19 cases, the location of plants in population-loss areas, and the presence of a severe weather event—increase slaughter reductions. These findings suggest physical capacity is not the only factor influencing processing rates and highlight existing vulnerabilities to labor shortages.

Encapsulation of atomized erythrocytes in liposomes as source of heme iron for oral supplementation strategies

AbstractThis work aimed to develop and characterize liposomes of atomized bovine erythrocytes (ABE‐liposomes) for potential use as a heme iron supplement or to fortify food with heme iron. Soy lecithin (SL) and Tween 80 (T80) were chosen to prepare empty liposomes (8 types), and ABE‐liposomes (16 types) by a rotary‐evaporated film method. Variables of interest for our study were: ABE concentration, proportion of SL:T80 and ultrasonic bath time. ABE‐liposomes were characterized according to appearance, color, morphology, Fourier transform infrared spectroscopy (FTIR), size, zeta potential, total iron content, encapsulation efficiency (EE) and in vitro iron release under gastrointestinal conditions. ABE‐liposomes presented a brown color and spherical shape. Hydrogen bridges were the main interactions in ABE‐liposomes. Their size ranged from 379 to 964 nm, the zeta potential from −56 to −74 mV, the iron concentration range was 0.8–9.0 mg/100 mL, and EE ranged from 29% to 48%. Ultrasonic bath time was the most important variable on the reduction of ABE‐liposomes' size and EE. Under in vitro gastrointestinal conditions, iron release from ABE‐liposomes occurred mainly at the intestinal level. In conclusion, ABE‐liposomes were effectively developed, which could become a complement for supplementation or food fortification strategies with nonheme for the prevention of iron deficiency anemia.Practical ApplicationsIn this study atomized bovine erythrocytes (ABE)‐liposomes were developed, due to the: (1) lack of supplements or products to fortify foods based on heme iron, (2) higher bioavailability of heme iron than nonheme iron, especially when working with ABE, and (3) ABE is a low value‐added product that is generated in slaughter plants and in turn is an excellent source of underutilized heme iron. In this study it was possible to develop ABE‐liposomes, where ABE was encapsulated inside liposomes, obtaining a product that could be used as a complement in iron supplementation strategies or food fortification to prevent or treat iron deficiency or iron deficiency anemia, especially in developing countries that have low consumption of heme iron.

Effects of stepwise chilling with calcium incubation on proteolysis and tenderization in postmortem goose muscle

White Roman goose (12-wk-old male, N=30) carcasses were obtained from a local government-inspected slaughter plant at approximately ∼10-min postmortem. Each carcass was individually sealed in a zip-lock bag and chilled immediately in a water bath at 15°C for 1 h. Both sides of Pectoralis major muscles were excised from each carcass and incubated in 30 mM CaCl2 or 30 mM EDTA at 15°C for 5 h. After incubation, calcium-incubated and EDTA-incubated breast muscles were vacuum-packaged individually and stored at 5°C for 72 h. Control samples (without CaCl2 or EDTA incubation) were directly vacuum-packaged and chilled in a water bath at 15°C for 5 h and stored at 5°C for 72 h. Muscle specimens were taken from the left side of breast muscles at 1 h of chilling (∼1-h postmortem) and at 5 h of incubation at 15°C (∼6-h postmortem), as well as 24, 48, and 72 h of aging at 5°C for measuring the activities of calpain-1 and calpain-11 as well as the contents of 80 kDa calpain-1 subunit and desmin. The samples of shear force value and myofibril fragmentation index (MFI) were taken from the right side of breast muscle at 24 h and 72 h of 5°C storage. Our results showed that the decrease of the activities of calpain-1 and calpain-11 and the contents of 80 kDa calpain-1 subunit and desmin was more rapid (P < 0.05) in calcium-incubated samples than in control and EDTA-incubated samples. The shear force was lower, but the MFI was higher in calcium-incubated samples than in control and EDTA-incubated samples (P < 0.05). Therefore, our results suggest that the calpain-mediated proteolysis and tenderization in postmortem goose muscle could be greatly enhanced by combine effects of stepwise chilling with calcium incubation at 15°C and thereafter aging at 5°C. With applying this procedure, commercial slaughter plants may have an alternative way to improve the tenderness of goose meat.

Core genome multilocus sequence typing (cgMLST) confirms systemic spread of avian pathogenic Escherichia coli (APEC) in broilers with cellulitis

Broiler cellulitis has emerged as an important cause of economic losses for farmers and slaughter plants from carcass condemnation at processing. Avian pathogenic Escherichia coli (APEC) has been identified as the main causative agent. The aim was to characterize E. coli isolated from cellulitis and organs in broilers at slaughter by whole genome sequencing analysis to study if systemic spread could be confirmed. Isolates were collected post-mortem from 101 carcasses condemned due to dermatitis/cellulitis from five commercial farms and six flocks. Forty-six isolates were characterised to determine serotypes, sequence types and virulence-associated genes. Analysis by cgMLST was performed to study the genetic similarity between isolates from the same broiler, among birds from the same flock and between flocks. Escherichia coli was isolated from 90% of birds from subcutaneous samples. In 20 broilers, E. coli was isolated from organs in pure culture or mixed with sparse growth of other bacteria. In eight of these, there were post-mortem findings suggestive of systemic bacterial spread. The majority of the isolates from the same bird and flock belonged to the same serotype and sequence type and were genetically indistinguishable, but differed when compared between flocks. Common APEC virulence genes, i.e. chuA, fyuA, hlyF, iroN, irp2, iss, ompT, sitA, TerC, TraT, were present in > 87% of the isolates. We conclude that evidence of systemic spread of E. coli from cellulitis was present in some birds at time of slaughter but cannot be reliably detected at meat inspection.

Answers to Patient, Student, and Clinician Questions About How Animals Are Slaughtered and Used for Food.

"Do cattle and other animals know they are walking up a chute that will lead to their death?" Many people ask this question, which the author first had to answer when starting work in the cattle industry. From observations at slaughter plants, feedlots, and ranches, the author learned that cattle behavior was the same when entering a chute for vaccination and when entering a chute for slaughter. If cattle knew they would die, their behavior should have been wilder and more agitated at the slaughter plant, but that was clearly not the case. This article canvasses points of ethical and clinical relevance for discussions about human dietary consumption and practice.

Biofilm removal mediated by Salmonella phages from chicken-related sources

Salmonella and their biofilm formation are the primary bacterial causes of foodborne outbreaks and cross-contamination. The objective of the study was to investigate the potential of Salmonella phages as an alternative technology for biofilm removal. In this work, 21 Salmonella phages were isolated from a chicken farm and slaughter plant and the phage (CW1) with the broadest spectrum was characterized. Complete genome sequence analysis revealed that the genomes of phage CW1 is composed of 41763 bp with 58 open reading frames (ORFs) and a holin-endolysin system and it does not encode any virulence or lysogeny. A phage cocktail consisted of CW1 (with the broadest spectrum of 70.49 %) and CW11, M4 and M10 (with a high lytic activity of more than 67.11 %) was established. Treatment with the cocktail reduced the cells in the developing biofilm and mature biofilm by 0.79 lg(CFU/cm2) and 0.4 lg(CFU/cm2), respectively. More dead cells and scattered extracellular polymeric substances (EPS) were observed by confocal laser scanning microscopy and scanning electron microscopy. Raman analysis found that carbohydrates and proteins were the identification receptors for scattered EPS. This finding suggests that this phage cocktail has potential applications for the sterilization of Salmonella biofilm during meat processing.

Despite Shared Geography, Campylobacter Isolated from Surface Water Are Genetically Distinct from Campylobacter Isolated from Chickens.

We tested the hypothesis that Campylobacter isolated from chicken ceca and river water in an overlapping geographic area would share genetic information. Isolates of C. jejuni from chicken ceca were collected from a commercial slaughter plant and isolates of C. jejuni were also collected from rivers and creeks in the same watershed. Isolates were subjected to whole-genome sequencing and the data were used for core genome multilocus sequence typing (cgMLST). Cluster analysis showed that there were four distinct subpopulations, two from chickens and two from water. Calculation of fixation statistic (Fst) showed that all four subpopulations were significantly distinct. Greater than 90% of the loci were differentiated by subpopulation. Only two genes showed clear differentiation of both chicken subpopulations from both water subpopulations. Sequence fragments of the CJIE4 bacteriophage family were found frequently in the main chicken subpopulation and the water outgroup subpopulation but were sparsely found in the main water population and not at all in the chicken outgroup. CRISPR spacers that targeted the phage sequences were common in the main water subpopulation, only once in the main chicken subpopulation, and not at all in the chicken or water outgroups. Restriction enzyme genes also showed a biased distribution. These data suggest that there is little transfer of C. jejuni genetic material between chickens and nearby river water. Campylobacter differentiation according to these two sources does not show clear evidence of evolutionary selection; the differentiation is probably due to geospatial isolation, genetic drift, and the action of CRISPRs and restriction enzymes. IMPORTANCE Campylobacter jejuni causes gastroenteritis in humans, and chickens and environmental water are leading sources of infection. We tested the hypothesis that Campylobacter isolated from chicken ceca and river water in an overlapping geographic area would share genetic information. Isolates of Campylobacter were collected from water and chicken sources in the same watershed and their genomes were sequenced and analyzed. Four distinct subpopulations were found. There was no evidence of sharing genetic material between the subpopulations. Phage profiles, CRISPR profiles and restriction systems differed by subpopulation.

An exploratory qualitative enquiry into workers' experiences of leptospirosis and post-leptospirosis in Aotearoa New Zealand.

This pilot study describes the experiences of six people who reported post-leptospirosis symptoms. Our aim was to perform an exploratory qualitative study to document participants' experiences and to identify themes to gain understanding of the impact and burden experienced. Participants self-recruited, meaning they had directly contacted the first author prior to the study commencing and had offered to tell their stories. Face-to-face semi-structured interviews were conducted in January 2016 and summative content analysis was used to distil themes. The participants were male, had been employed in livestock slaughter plants (n=2) or farming (n=4) when they first contracted leptospirosis and claimed they had been suffering from post-leptospirosis symptoms for 1-35 years. Symptoms included exhaustion, brain fog and mood swings, and participants' lifestyles and relationships were severely affected. Participants and their partners reported poor awareness and knowledge of leptospirosis when they sought help, and that employers and the Accident Compensation Corporation (ACC) were dismissive of post-leptospirosis symptoms. Participants also reported some positive experiences and had advice to share. Leptospirosis may have severe long-term consequences for patients, their families and their communities. We recommend that the aetiology, pathogenesis and burden of the persistence of leptospirosis symptoms become topics for future research.

Resilience of U.S. Cattle and Beef Sectors: Lessons from COVID-19

Abstract The upheaval wrought on the U.S. beef industry by the global COVID-19 pandemic carried with it several lessons that might help improve resiliency should there be a reoccurrence. First, the futures market for fed cattle fell well before cash prices, which sent a signal to market cattle early, and those who did so benefited. Second, the decline in futures anticipated the closure of slaughter plants and provided an opportunity to purchase and store beef primals in anticipation of future scarcity. Third, the beef industry has ways of slowing or stopping the pipeline of animals destined for feed yards and can “store” these animals in background feeding facilities or on pasture or rangeland. Producers who waited to sell feeder cattle benefited from higher feeder cattle prices once the processing facilities reopened. Fourth, cow slaughter plants responded to the pandemic and subsequent scarcity of labor much better than large fed-cattle plants. Cow plants are not as sophisticated and complex as fed-cattle plants. This relative simplicity may help explain the superior performance of these plants during the crisis. Sixth, the academic work on the value of building smaller plants as a response against concentration provides mixed results—these plants require more labor per animal and can be even more susceptible to labor scarcity. Seventh, the observed increase in boxed beef prices, even as fed cattle prices fell, demonstrates the risk-mitigating impact of producer ownership of downstream activities in the value chain.

Evaluation of an Innovative Zn Source on Feed Efficiency, Growth Performance, Skin and Bone Quality of Broilers Suffering Heat Stress.

One thousand two hundred male broilers were used to evaluate the effect of different dosages of HiZox® on feed efficiency, growth performance and bone quality of broilers suffering from heat stress. A completely randomized design was used, with four treatments and ten replicates. Basal corn−soybean meal diets supplemented with 75, 100 and 125 mg/kg zinc from HiZox and 100 mg/kg zinc from regular ZnO were used to make four treatments. Heat stress was induced after the third week by keeping house temperature between 28−34 °C, from 1 pm until 5 pm. The body weights of the birds that received the diet supplemented with HiZox or ZnO showed no significant difference at 7 and 14 days. Body weight of heat stressed birds fed diets containing different levels of HiZox or ZnO were not different at 28 and 42 days of age. In comparison to the Ross 308 management guide, induced heat stress diminished body weight and feed intake by approximately 17 and 21%, respectively. At 28 days, chickens who received 125 mg/kg Zn from Hizox had better feed efficiency (p < 0.05). The mortality rate of heat-stressed male broiler chickens who received different dosages of HiZox was 2.85% less than that of the regular ZnO group (p < 0.06). The results showed that addition of HiZox to the diet of male broiler under heat stress doubled the skin resistance during feather plucking in the slaughter plant and improved carcass quality (p < 0.07). Tibia breaking strength, included elongation and extension were improved by consumption of a diet supplemented with 75 mg HiZox/kg (p < 0.09). The HiZox-75 fed broilers required higher amounts of energy (MJ) for tibia breaking at break and peak points at 42 days (p < 0.09; p < 0.07). Jejunum Zn concentrations reflected the quantity of ingested Zn (p < 0.0001). Gizzard Zn solubility was dependent on dietary treatment (p < 0.03). Solubility of Zn in the gizzard of chickens who received HiZox was higher (about 30%) than broilers fed regular ZnO. In conclusion, Zn from HiZox was more efficient in decreasing heat stress mortality, increasing skin resistance and bone breaking strength compared to a regular ZnO source.

Mortality during Transport of Pigs Subjected to Long Journeys: A Study in a Large European Abattoir.

To date, especially in Europe, few studies have analysed the implications of long journeys on pig welfare and economic losses, expressed in terms of transport mortality. This study retrospectively analysed data collected from slaughtering registers and travel journals in a large Italian abattoir. We focused on pig transports coming from abroad and arriving at the slaughter plant after long journeys (a total of 59,982 pigs over 370 journeys). We explored the relationship between mortality and the following variables: country of origin, journey duration, astronomical season, stocking density on the truck, number of stops, and prolonged stops during the journey (lasting more than 60 min, likely due to traffic jams or truck problems). Overall, the low mortality rate observed (0.09%) was in line with European estimates. The factors with a significant or tendential effect on mortality during transport were the astronomical season (p = 0.0472, with higher mortality in spring) and the presence of prolonged stops during the journey (p = 0.069, tendential effect). Journey duration, stocking density, country of origin, and the number of stops were not statistically significant. In conclusion, based on this case study, using transport mortality combined with data collected during the common routine activity by the Public Veterinary Services in slaughterhouses could be a simple screening method for identifying problematic journeys or transport conditions.