Effect of the pre-slaughter logistic chain on some indicators of welfare in lambs

The Protective Role of Heat Shock Proteins against Stresses in Animal Breeding

Heat shock proteins (HSPs) play an important role in all living organisms under stress conditions by acting as molecular chaperones. The expression of different HSPs during stress varies depending on their protective functions and anti-apoptotic activities. The application of HSPs improves the efficiency and decreases the economic cost of animal breeding. By upregulating the expression of HSPs, feed supplements can improve stress tolerance in farm animals. In addition, high expression of HSPs is often a feature of tumor cells, and inhibiting the expression of HSPs is a promising novel method for killing these cells and treating cancers. In the present review, the findings of previous research on the application of HSPs in animal breeding and veterinary medicine are summarized, and the knowledge of the actions of HSPs in animals is briefly discussed.

Electro-thermal injuries in ruminants caused by electrical equipment during pre-slaughter operations: Forensic case reports from an animal welfare science perspective

The use of electrical equipment for herding and moving livestock (electric batons) or for stunning animals before slaughter (electric stunners) is widespread in the livestock and meat industries worldwide. The use of these equipment is restricted to specific procedures and/or exceptional circumstances that justify their rational use. However, these restrictions can be underestimated or disregarded due to ignorance, inexperience, incompetence or irresponsibility on the part of users, resulting in pain and suffering to the animals and, in some cases, electro-thermal injury. This report presents four forensic cases of electro-thermal injuries identified during post-mortem animal welfare assessments in slaughterhouses in Colombia, Mexico and Spain. Electro-thermal injuries caused by contact (accidental or intentional) of equipment electrodes with skin and subcutaneous tissue are presented. Although our cases are isolated events detected over a 5-year period, they provide a useful visual guide for technicians and veterinarians interested in the differential diagnosis between bruises and electro-thermal injuries. The differentiation of the equipment causing the injuries allows the identification and control of critical points for animal welfare along the pre-slaughter logistic chain and the elimination of inappropriate animal handling practices.

Physiological and immune responses to long road transportation in Andaman local pigs

Transportation of farm animals is a routine management practice. During transportation, animals experience physiological and psychological stress which has negative consequences on health and welfare of animals. Effect of transportation on pig health and welfare in island ecosystem is not properly known. Here, we report the effect of transportation stress under island ecosystem on serum biochemical parameters, lipid profile, stress biomarkers, and immune parameters in Andaman local pig. Twelve pigs were transported from North and Middle Andaman to South Andaman via road in which two small sea channels have to be crossed in ferry with vehicle on board. Transportation triggered increase in serum levels of total protein and albumin. Elevated levels of aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, lactate dehydrogenase, and creatine kinase in transported pigs indicated muscular exercise or impaired liver function. Transportation induced dyslipidemia indicated by elevated levels of total cholesterol, low-density lipoprotein cholesterol, and triglycerides and a decreased level of high-density lipoprotein cholesterol. High level of serum total nitric oxide and serum MDA as well as low antioxidant capacity in transported pigs indicated oxidative stress induction. Transportation resulted in activation of stress response and increased levels of serum cortisol and heat shock proteins were recorded in transported pigs. Moreover, increased concentration of pro-inflammatory cytokines (IL-2, IL-6, IL-12, IL-1β, and IFN-γ) and decreased concentration of anti-inflammatory cytokine IL-4 were detected in transported pigs. The results of the study are helpful for better understanding of transportation stress in pigs under island ecosystem.

Impact of Stress on Health and Final Weight in Fattening Lambs

Simple Summary

In recent years, the lamb production system in North-Eastern Spain has undergone an important change and the number of lamb feedlots has increased significantly. However, the possible impact of stressors associated with this production system on the health and productive performance of the lambs has not been investigated. In this study, the stress level of Rasa Aragonesa fattening lambs, finished at a commercial feedlot or on the farm of birth, was measured throughout the fattening period. Our results show that, although feedlot lambs seemed to have experienced higher stress levels than those fattened on the farm of origin, finishing location did not affect the probability of presenting clinical signs of illness and ovine respiratory complex lesions, or the final weight of the lambs. Notwithstanding, associations were found between the concentration of fecal cortisol metabolites (a chronic stress indicator) at the time of weaning and the health condition and the final weight of the lambs, regardless of the location at which they were fattened. The stress level experienced by lambs prior to finishing seems to be relevant for their health and productive performance, and measures to reduce this stress should be further investigated as a useful tool to improve the sustainability of the ovine production system.

Abstract

In order to determine whether the stress level had any influence on the health and final weight of Rasa Aragonesa fattening lambs, stress markers were measured throughout the fattening period in 80 feedlot lambs (group F) and in 40 lambs finished on the farm of birth (group C). The highest values of the stress indicators—neutrophil-to-lymphocyte-ratio (N/L), non-esterified fatty acids (NEFA), serum cortisol and fecal cortisol metabolites (FCM)—were recorded after the road transportation of group F to the feedlot. No differences between the groups were identified at the end of the adaptation period, but at the end of the fattening, statistically significant higher values for NEFA and serum cortisol were determined in group F. However, statistically significant differences between the groups were not found in the percentage of lambs with clinical signs of illness and ovine respiratory complex (ORC) lesions or in the final weight of the lambs. Independent of the location at which the lambs were fattened, those with FCM values at the beginning of the study (at the time of weaning) in the highest quartile developed a higher percentage of clinical signs of illness (45.5% vs. 32.1%, p > 0.05) and ORC lesions (45.5% vs. 10.7%, p < 0.01), and their average final weight was lower (24.36 kg vs. 27.40 kg, p = 0.001) than those with values in the lowest quartile. Stress experienced by lambs prior to finishing seems to be relevant for their further development, and FCM concentration at the time of weaning could be used as an indicator of health and productive performance of the lambs during the fattening period, regardless of finishing location.

Effect of information on geographical origin, duration of transport and welfare condition on consumer's acceptance of lamb meat

Animal production system and welfare conditions can influence consumers’ acceptance, as meat from animals grazing in natural pasture and labelled with information about high standards of welfare is preferred. In addition, geographical origin of food is recently considered one of the main information influencing the consumers’ acceptance. Local products are collectively associated with high quality attributes by the consumers related to shorter transport and good welfare. Lamb meat is considered local and typical food; however, it is common to find in the same market both local and imported lamb meat. The present investigation aimed at understanding the importance of information about geographical origin, transport duration, and welfare condition of lambs for consumers and their actual liking. Moreover, the quality of lamb meat from local and imported animals as affected by short or long transport was assessed. Data demonstrated that both short and long transport did not affect organoleptic quality of meat; this result was corroborated by an absence of both metabolic and immune stressors in long term transport lambs except for haptoglobin, cortisol and glucose. However, the expected and actual acceptability were affected by the information with higher scores for local lamb when information on the geographical origin, transport duration, and welfare condition was provided to the consumers.

Investigating the Role of Prolactin as a Potential Biomarker of Stress in Castrated Male Domestic Dogs

Prolactin has been recently regarded as a potential biomarker of both acute and chronic stress in several species. Since only few studies until now have focussed on domestic dogs, this study was aimed at evaluating whether prolactin, cortisol and stress behaviour correlated with each other in sheltered dogs. Both cortisol and prolactin analysis were performed in serum samples through a hormone-specific ELISA kit. For each dog, a stress score was calculated by summing the number of occurrences of stress-related behaviours. The presence/absence of fear during the time spent in the collection room was also scored for each individual. Results revealed a weak negative correlation between cortisol and prolactin levels. Neither of the hormones was correlated with the stress score, nor did their values seem to be influenced by showing fear in the collection room. The weak negative correlation found between cortisol and prolactin values agrees with results obtained in other studies, indicating that prolactin response might be an alternative to cortisol response. This, together with the high serum prolactin levels compared to those reported by other authors for healthy domestic dogs, may indicate that prolactin might be a good biomarker of chronic stress, and although further studies are needed to better understand the potential role of prolactin in the evaluation of canine welfare.

Effect of bedding materials during transport on welfare indicators and microbiological quality in lambs

Three bedding materials, sawdust, rice husk and double layer of sawdust used during transportation to slaughterhouse were compared. Sixty light male lambs of Merino breed were used in the present study. Welfare physiological indicators (glucose, lactate, creatinine, lactate dehydrogenase, creatine kinase, cortisol and catecholamine) sampled before and immediately after the transportation, and carcass microbial quality (total viable counts, Enterobacteriaceae and Pseudomonas spp.) in three different sites of carcass (rump, flank and neck) were assessed. Bedding material during transport did not affect any of the physiological indicators analysed, except for creatinine, which was lower in lambs transported with rice husk. Bedding material had no effect on carcass microbial quality. Sampling site affected values of Enterobacteriaceae and Pseudomonas spp. The lowest values for Enterobacteriaceae count were found in the neck, while Pseudomonas spp. presented the highest count in the flank site. In conclusion, under the conditions of the present study, all substrates tested could be recommended as bedding material during transport, without showing significant differences on animal-welfare indicators or carcass microbiological quality.

Effect of diet supplementation with the addition of Saccharomyces cerevisiae upon stress response in slaughter lambs

The study included 2 groups of lambs (GL): control (C) and experimental (E) which since day 11 of life was receiving an addition of dried Saccharomyces cerevisiae preparation. At the age of 100 days, 12 lambs from each group were weaned from mothers for 12-h pre-slaughter fasting, and transported to a slaughter house. Blood was sampled for analyses: before weaning from mothers (BST 1), before and after transport (BST 2 and 3). Blood samples were assayed for: values of neutrophils and lymphocytes, N:L (neutrophils to lymphocytes ratio), cortisol and glucose. After 24-h chilling of lamb carcasses, musculus longissimus dorsi was subjected to measurements of final acidity (pH24) and colour (CIE Lab), and muscle samples were collected for evaluation of water absorption and shear force. The GL and BST had a significant effect on the N:L ratio. No significant differences were found in the cortisol concentration between groups of lambs. This indicator was significantly different in the analyzed blood sampling time (P < 0.01). In the entire period of pre-slaughter handling, in group C cortisol concentration increased × 8.5, whereas in group E it increased × 4.3 compared to the baseline value. In both groups, the study showed an increase (P < 0.01) in glucose concentration in BST 3 compared to BST 1 and BST 2. Meat of lambs from group E was characterized by lower (P < 0.05) values of pH24, WHC, SF, and indicator a*. The obtained results suggest the advisability of applying a preparation of dried brewer’s yeast in rearing slaughter lambs in order to strengthen their immunity and to alleviate effects of pre-slaughter stress.

Thermophysiological, haematological, biochemical and behavioural stress responses of sheep transported on road

The study was conducted to evaluate the thermophysiological, haematological, biochemical and behavioural stress responses of sheep transported on road. A total of 44 Chamarita breed adult ewes were randomly allotted to one of two groups, one control group (untransported) and transported group (journey of 4 h), and blood stress indicators were measured 1 day before transport and at four time points post-transport (0, 4 and 24 h). Thermophysiological profiles of ewes were measured by temperature buttons (iButton Thermochron^® ) and placed in intravaginal sponges. Direct observations, with a combination of scan and behaviour sampling, were carried out to collect information on individual behaviour and the time it took the ewes to drink water, eat and rest after returning to their pen respectively. Transported ewes lost approximately 1 kg live weight compared to controls and had higher body temperatures until 12 h post-transport. Cortisol, glucose, non-esterified fatty acid (NEFA) concentrations as well as the neutrophil-lymphocyte ratio (N/L) and other physiological indicators were higher immediately after unloading in transported ewes but mostly returned to normal after 4 h, with complete recovery after 24 h. Behavioural analysis post-transport demonstrated that transported ewes chose to eat before drinking and spent less time resting than controls in the first 3 h after unloading. The study demonstrates that transportation even under short-journey conditions induced behavioural, physiological and thermophysiological responses indicative of the induction of significant stress, leading to live weight shrinkage that may jeopardize farmer's incomes. Finally, results of this study validated the use of iButton Thermochron^® data loggers for monitoring the stress response during transport.

Effect of postweaning handling strategies on welfare and productive traits in lambs

Postweaning management strategies that include an element of social enrichment may reduce weaning stress and improve welfare and productive performance. We analyzed the effect of postweaning handling strategies on welfare and production traits in lambs. After weaning, 36 lambs were assigned to 3 experimental groups with 12 lambs each (control [C], fattening with gentle human female contact [H], and fattening with 2 adult ewes [E]). The average daily gain (ADG) was estimated. Blood samples were taken, and infrared thermography was used to estimate stress variables. There were significant differences among treatments (in favor of alternative strategies) regarding production and stress variables (cortisol, glucose, and creatine kinase). The results suggest that the lambs handled gently during the fattening were less reactive and better able to modulate their physiological stress. The E group adapted better to acute stress than the C group but was less efficient in modulating chronic stress. Both treatments showed higher slaughter live weights and better ADGs compared with the control. The use of social enrichment at weaning, especially to establish a positive human-nonhuman animal bond, alleviates lamb weaning stress and improves welfare and performance.

Relationship between cortisol and acute phase protein concentrations in female rabbits

Rabbit meat production in Europe is usually based on a semi-intensive system, in which lactation and gestation overlap. The demands of lactation and pregnancy are likely to be relatively stressful for female rabbits and may compromise the immune system and reproductive performance. The present study was designed to characterise circulating levels of cortisol, haptoglobin (Hp), C-reactive protein (CRP), and serum amyloid A (SAA) in non-lactating and lactating female rabbits at first and second mating, and to determine whether any relationship exists between these biomarkers and litter size. Serum cortisol concentrations were at their greatest (mean ± SEM = 39.5 ± 3.9 nmol/L) in animals at the end of lactation. However, after weaning, cortisol concentrations were not significantly different compared to nulliparous females (19.9 ± 3.6 vs. 16.3 ± 2.2 nmol/L, respectively). The highest concentrations of circulating Hp (0.14 ± 0.01 g/L) were seen in early lactating primiparous females, and lower in nulliparous females and in rabbits after weaning. In contrast, nulliparous female rabbits showed the highest plasma CRP values (13.1 ± 1.1 mg/L). No significant differences were found for SAA. Nulliparous females had smaller litter sizes than early lactating and non-lactating primiparous female rabbits. CRP and SAA showed a positive correlation (r = +0.24, P = 0.011) and were negatively related to litter size (r = -0.23, P = 0.017 and P = 0.032, respectively). Cortisol and Hp were not related to CRP, SAA, nor to litter size. These results suggest a closer association between the mechanisms that regulate release of CRP and SAA, compared to those that regulate Hp production. Thus, lactation is associated with changes in several stress biomarkers. CRP and SAA might be more useful for evaluating animal welfare and for predicting subsequent reproductive performance of female rabbits.

Livestock transport from the perspective of the pre-slaughter logistic chain: a review

New developments in livestock transport within the pre-slaughter chain are discussed in terms of three logistic nodes: origin, stopovers and slaughterhouse. Factors as transport cost, haulier, truck specifications, micro-environment conditions, loading density, route planning, vehicle accidents and journey length are discussed as well as causes of morbidity, mortality, live weight and carcass damage. Taking into account current trends towards increased transport times, logistics stopovers and mixed transport, there is a need to develop systems of evaluation and decision-making that provide tools and protocols that can minimize the biological cost to animals, which may have been underestimated in the past.

Effect of enriched housing on welfare, production performance and meat quality in finishing lambs: the use of feeder ramps

This study analyses the effect of environmental enrichment on the welfare, productive traits and meat quality of lambs housed in feedlots. Sixty lambs were placed in enriched (EE) or conventional (CO) pens (3 pens for each treatment, 10 lambs/pen) where EE had a wooden platform with ramps that provided access to a concentrate hopper, cereal straw as bedding and forage, and one play ramp. The CO pen was barren, similar to commercial feedlots. The physiological adaptation response of EE lambs was more efficient than CO, since the latter mobilised more body reserves (i.e., increased NEFA, P<0.05), and had lower levels of immunity (i.e., increased N/L, P<0.05), which indicate chronic stress, probably associated with the barren environment. The EE lambs had a higher (P<0.05) average daily gain, with heavier carcasses and higher fattening scores, as well as lower pHult, higher L and b values, and lower values of texture (P<0.05).

The Effects of Pre-slaughter Stress and Season on the Activity of Plasma Creatine Kinase and Mutton Quality from Different Sheep Breeds Slaughtered at a Smallholder Abattoir

The objective of the current study was to determine the effect of pre-slaughter stress, season and breed on the activity of plasma creatine kinase (CK) and the quality of mutton. One hundred and seventy-three (173) castrated sheep from Dormer (DM), South African Mutton Merino (SAMM), Dorper (DP) and Blackhead Persian (BP) sheep breeds were used in the study. The animals were grouped according to age-groups as follows: Group 1 (6 to 8 months), Group 2 (9 to 12 months) and Group 3 (13 to 16 months). Blood samples were collected during exsanguinations using disposable vacutainer tubes for CK analysis. Representative samples of the Muscularis longissimuss thoracis et. lumborum (LTL) were collected from 84 castrated sheep, of different breeds (28 per breed) 24 h after slaughter. The following physico-chemical characteristics of mutton were determined; meat pH (pH24), color (L*, a* and b*), thawing and cooking losses and Warner Braztler Shear Force (WBSF). The activity of plasma CK was significantly higher (p<0.001) in summer (1,026.3±105.06) and lower in winter (723.3±77.75). There were higher values for L* (33.7±0.94), b* (11.5±0.48) and WBSF (29.5±1.46) in summer season than in winter season; L* (29.4±0.64), b* (10.2±0.33) and WBSF (21.2±0.99). The activity of plasma CK was influenced by the type of breed with Dormer having the highest (p>0.001) levels (1,358.6±191.08) of CK. South African Mutton Merino had higher values for pH24 (5.9±0.06), L* (34.2±0.97), b* (12.2±0.50) and WBSF (26.8±1.51) and Blackhead Persian had higher values (35.5±2.17) for cooking loss (CL%) than the other breeds. Computed Principal Component Analyses (PCA) on the activity of plasma CK and physico-chemical characteristics of mutton revealed no correlations between these variables. However, positive correlations were observed between pH24, L*, a*, b*, CL% and WBSF. Relationships between pre-slaughter stress, CK activity and physico-chemical characteristics of mutton were also observed. It was therefore concluded that although mutton quality and creatine kinase were not related, pre-slaughter stress, season and breed affected the activity of creatine kinase and mutton quality.

Hsp70 and HSF-1 expression is altered in the tissues of pigs transported for various periods of times

The aim of this study was to assess changes of Hsp70 and HSF-1 protein and mRNA expression in stress-sensitive organs of pigs during transportation for various periods of time. Twenty pigs were randomly divided into four groups (0 h, 1 h, 2 h, and 4 h of transportation). A significant increased activity of AST and CK was observed after 1 h and 2 h of transportation. Histopathological changes in the heart, liver, and stomach indicated that these organs sustained different degrees of injury. Hsp70 protein expression in the heart and liver of transported pigs did not change significantly while it increased significantly (p < 0.05) in the stomach. Hsp70 mRNA levels decreased significantly (p < 0.05) in the heart after 4 h of transportation. However, mRNA expression increased significantly in the liver after 1 (p < 0.05) and 4 h (p < 0.01) of transportation, and increased significantly in the stomach of the transported pigs after 1, 4 (p < 0.01), and 2 h (p < 0.05). HSF-1 levels were reduced at 1 and 4 h (p < 0.05) only in the hearts of transported pigs. These results indicate that Hsp70 mediates distinct stress-related functions in different tissues during transportation.

Serum cortisol and haematological, biochemical and antioxidant enzyme variables in horse blood sampled in a slaughterhouse lairage, immediately before stunning and during exsanguination

The aim of the study was to determine changes of serum cortisol and biochemical, haematological and antioxidant enzyme variables in the blood of horses sampled during the pre-slaughter period (in the lairage and in the stunning box) and during exsanguination. A total of 24 Slovenian warm-blooded horses were observed. Blood samples for determination of serum cortisol and biochemical, haematological (red blood cell count, haematocrit, haemaglobin concentration) and antioxidant enzyme (whole blood superoxide dismutase and glutathione peroxidase) variables were collected by venipuncture of the left jugular vein in the lairage pen, 60 min before stunning (lairage) and immediately before stunning (stunning box). At exsanguination, blood samples were collected from the wound at the time of jugular vein sticking. During blood collection in the lairage pen and in the stunning box, horses were gently restrained with a halter. They were stunned using a penetrating captive bolt pistol impelled by air and were bled by jugular vein sticking. Horses were physically active in the lairage pen and in the race before entering the stunning box. After stunning, the horses showed paddling movements with their legs. In horses, the plasma lactate and glucose concentrations, the serum potassium concentration, the activities of the serum muscle enzymes aspartate aminotransferase and creatine kinase, and values of most of the other biochemical (Table 1) and haematological variables (Table 2), were significantly (P < 0.05) higher at exsanguination, than in blood sampled while they were in the lairage and in the stunning box. The serum concentrations of cortisol and chloride and the activities of alanine aminotransferase and antioxidant enzymes were not significantly different between the pre-slaughter period and exsanguination. All selected blood variables were not significantly different between the lairge and the stunning box sampling time, indicating no physiological stress responses of the investigated horses to stressors, such as novelty of the pre-slaughter environment and handling, present in the slaughterhouse between the lairage and the stunning box. However, the significantly higher values, at exsanguination, for the plasma lactate and glucose concentrations, serum muscle enzyme activities and haematological variables, than during the pre-slaughter period, might partially be attributed to stimulation of the sympathetic nervous system, caused by stunning and bleeding.

Effects of road type during transport on lamb welfare and meat quality in dry hot climates

This study determined whether transporting lambs on paved (PR) or unpaved roads (UR) for 3 h had an effect on plasma stress indicators (cortisol, lactate, glucose, creatine kinase [CK], red blood cells, white blood cells, hematocrit, and neutrophil/lymphocyte [N/L] ratio) and instrumental meat quality (pH24, bruising score, water holding capacity [WHC], color, and texture). A total of 48 Rasa Aragonesa male lambs were used that were approximately 100 days old (12.5 kg ± 1.64, carcass weight). The results suggest that transport on unpaved roads had a significant influence on physiological and hematological stress parameters. Road type had a significant effect on all variables, except for white and red blood cells, and hematocrit levels. The UR lambs had significantly higher (at least p ≤ 0.01) cortisol, lactate, glucose, and CK levels and a higher N/L ratio than PR lambs. Meat from UR lambs had some dark-cutting characteristics, with a darker color, higher ultimate pH, and higher tenderness values than PR. In conclusion, lambs transported on unpaved roads had a more intense stress response and poorer meat quality than lambs transported on paved roads. An effort to improve the logistics associated with route planning is necessary to prevent welfare problems during transport to slaughter.

Effect of lairage on lamb welfare and meat quality

The study analysed the effect of lairage on some indicators of welfare and meat quality in lambs. Forty-eight lambs were divided into two treatments: T1 without lairage and T2 with 12 h of lairage. Blood samples were collected at slaughter to analyse cortisol, lactate, glucose, creatinine kinase, non-esterified fatty acid, white blood cells, red blood cells, haematocrit and ratio of neutrophil : lymphocytes. Meat from the M. longissimus was analysed in terms of pH 24 h post-mortem, water-holding capacity, texture and colour. Sensory analyses were performed by a trained panel. Lairage had a significant effect on stress response, but had no effect on haematological variables. The lambs with a lairage period before slaughter (T2) had significantly (P ≤ 0.001) lower values of cortisol at the time of slaughter. A similar result was observed for lactate and glucose, with T1 lambs showing significantly (P ≤ 0.05) higher values than T2 lambs. The creatinine kinase activity and non-esterified fatty acid concentrations were highest in T2 lambs (P ≤ 0.05). Instrumental and sensory meat quality were not affected, with the exception of water-holding capacity and some meat colour indicators. The water-holding capacity was significantly higher for T2 (P ≤ 0.05), while T1 lambs had a higher yellow index (P ≤ 0.05) and hue (P ≤ 0.05). The results obtained in this study suggest that animals will be less stressed at the time of slaughter with an overnight lairage compared with slaughter on arrival at the abattoir. While stress at the time of slaughter can influence meat quality, these changes were small and always within the normal commercial range.