Resumo
This study aimed to evaluate the thermal response of the eyelids and lacrimal gland of the left eye (LETG) through infrared thermography (IRT), cardiorespiratory parameters, and their association with nociception and pain in bitches undergoing elective ovariohysterectomy (OVH) anesthetized with isoflurane and epidural analgesia. Twenty-one healthy bitches of different breeds were randomized into three groups receiving epidural blocks: GL (n=7), lidocaine (2 mg Kg-1 ); GLF (n=7), lidocaine (2 mg Kg-1 ) and fentanyl (3 µg Kg-1 ); and GLM (n=7), lidocaine (2 mg Kg-1 ) with morphine (0.1 mg Kg-1 ). IRT and cardiorespiratory parameters were evaluated at baseline (Ebasal), thirty minutes before anesthetic premedication, and at different surgical events: first incision (EInc), ligature and section of the left (ELoV), and right (ERoV) ovarian pedicle, ligature, and re-section of the cervix (EUt), and skin suture (ESut). The assessment of acute pain in the immediate post-operative period was registered at E1h, E2h, and E3h using IRT, the Dynamic Interactive Visual Analogic Scale (DIVAS), and the University of Melbourne Pain Scale (UMPS) scales. The results showed a statistically significant decrease in the lower eyelid surface temperature (LELT) during EInc for GL (32.9°C ± 0.62), in comparison to GLF (34.2°C ± 0.62) and GLM (35.3°C ± 0.62) (P = 0.006). Regarding LETG, a significant increase (P = 0.03) in the IRT of Ebasal (36.8°C ± 0.63) and EInc (36.1°C ± 0.63) for GLM was observed in comparison to the thermographic values for both perioperative events and groups. The GLM showed a significant decrease in IRT values of ERoV at E3h in the upper and lower eyelids (P = 0.03 and P = 0.01, respectively). A progressive and significant reduction of the IRT values of LETG was also recorded in GLM, with differences in ERoV (35.2 °C ± 0.63) (P = 0.02) and E3h (35.3 °C ± 0.63) (P = 0.01). The cardiovascular parameters (SAP, DAP, and MAP) did not differ between treatments, but in GL, there was a significant difference (P = 0.01) during EInc and ESut, compared to Ebasal. In the body temperature, EInc and ESut gradually decreased in all treatment groups (P = 0.01). In conclusion, hemodynamic and cardiorespiratory stability was associated with IRT readings and the absence of nociception. Changes in superficial temperature in the immediate post-operative period were lessened using isoflurane and epidural analgesia of lidocaine alone or in combination with pure opioids. These findings were clinically validated to the DIVAS and UMPS acute pain assessment scales.
Assuntos
Animais , Cães , Ovário/cirurgia , Doenças do Cão , Histerectomia/veterinária , Isoflurano/administração & dosagem , Anestesia Epidural/veterináriaResumo
Transport is considered a stressful period for livestock that can cause economic and biological losses if inadequate handling procedures exist. Several manuals and guides include recommendations for common domestic species based on scientific evidence. Still, the legislative freedom of each country means that they are not mandatory worldwide, nor do they cover all species, such as the water buffalo (Bubalus bubalis). This review aims to analyze the legal strictures currently applicable to the transport of this species. Critical aspects of the legislation that address the pre-transport, transportation, and post-transport stages are discussed, focusing on Asian and Latin American countries and the European Union. Areas of opportunity to improve the norms and laws that impact public policies, civil aspects, and water buffalo welfare in production systems are elucidated.
Assuntos
Animais , Bovinos , Bem-Estar do Animal , Búfalos , LegislaçãoResumo
Elephants use different thermoregulatory mechanisms that depend on the anatomical and morphological characteristics of the species. The crevices and wrinkles of the skin enhance the water-retention capacity of the epidermis. The highly vascularized ear is another region of particular interest, as its movement and vasomotor changes promote heat dissipation. Generally, these mechanisms are modulated by the hypothalamic thermoregulatory center and by the peripheral response of animals. Nonetheless, elephants are currently exposed to alterations in their habitats, such as global warming and climatic changes, which challenge their homeothermy. This article aims to discuss the thermoregulation mechanisms of African (Loxodonta africana) and Asian (Elephas maximus) elephants from an anatomical, physiological, and behavioral basis. The practical implications of these elements will be analyzed to implement tools, such as infrared thermography, or environmental enrichment, as strategies to promote the thermal balance of elephants.
Assuntos
Animais , Comportamento Animal , Regulação da Temperatura Corporal , Elefantes/anatomia & histologia , Elefantes/fisiologiaResumo
It is well known that transporting livestock is stressful for the animals and a primary cause of skin lesions. The effects of transport on the water buffalo (Bubalus bubalis) have not been studied extensively despite reports of high incidences of trauma during and after these mobilizations. The present review article analyzes the frequency of skin injuries suffered by water buffaloes during transport and several key contributing factors. It also discusses the consequences of injuries on the quality of carcasses. Important aspects identified include inappropriate vehicle design that does not comply with the dimensions recommended by international institutions (e.g., height, type of flooring, characteristics of the ramp), handling methods, and the ability of stock people to manage water buffaloes, all of which impact the incidence of injuries. Our analysis of these elements will contribute to identifying critical control points and areas of opportunity while also suggesting strategies to ensure the welfare of these animals during transport and the quality of water buffalo products and by-products.
Assuntos
Animais , Curtume , Meios de Transporte/métodos , Ferimentos e Lesões/veterinária , Búfalos/lesões , Contusões/veterinária , Carne Vermelha/análise , Bem-Estar do AnimalResumo
This study aims to review the current available literature regarding circus animals from the perspective of the five domains proposed for evaluating animal welfare to identify the critical points in the use of these animals and understand how circus spectacles affect their mental state and health. Exhibiting animals in circuses continues to be a popular practice today in some countries such as Germany, Spain, or Australia. However, animals' biological needs are not always prioritized due to the inadequate diets, reduced housing spaces, deficient social interaction, and handling that predisposes them to develop stereotypies and alter mental states due to chronic stress. Animal circuses are considered a controversial practice that can decrease the welfare of animals. Understanding the possible negative consequences on animal welfare (mental state and physical health) could contribute to planning strategies to improve the quality of life of wildlife animals exhibited in circuses worldwide.
Assuntos
Humanos , Animais , Comportamento Animal/classificação , Bem-Estar do Animal/ética , Técnicos em Manejo de Animais/normas , Animais Selvagens/psicologia , Comportamento EstereotipadoResumo
Adaptation to extrauterine life brings about various changes, which initially are reflected in physiological alterations in the newborn puppy. Also, the newborn puppy's thermoregulating capacity is deficient, and many of the physiological processes for survival depend on this capacity. Severe modifications in body temperature can lead to hypothermia in a few hours. Hence, the first 24 to 72 h of life correspond to the highest risk time, in which the newborn can course with moderate to severe hypothermia because the shivering reflexes and vasoconstriction mechanisms are not yet developed in the newborn of this species. Temperature stabilization is reached up to the 18th day of age. However, the colostrum's adequate consumption could provide a high energy supply, contributing to a fast recovery of temperature and, consequently, to a high survival rate. This review aims to analyze the factors that affect thermoregulation of the newborn puppy, the physiological and behavioral responses, as well as to discuss the influence of the colostrum as an energy source and production of heat to face hypothermia, aside from discussing recent scientific findings of infrared thermography (IRT) used to assess the thermal response of the newborn puppy to cope with hypothermia.(AU)
Assuntos
Animais , Recém-Nascido , Cães , Homeostase/fisiologia , Cães/crescimento & desenvolvimento , Comportamento/fisiologia , ColostroResumo
Adaptation to extrauterine life brings about various changes, which initially are reflected in physiological alterations in the newborn puppy. Also, the newborn puppy's thermoregulating capacity is deficient, and many of the physiological processes for survival depend on this capacity. Severe modifications in body temperature can lead to hypothermia in a few hours. Hence, the first 24 to 72 h of life correspond to the highest risk time, in which the newborn can course with moderate to severe hypothermia because the shivering reflexes and vasoconstriction mechanisms are not yet developed in the newborn of this species. Temperature stabilization is reached up to the 18th day of age. However, the colostrum's adequate consumption could provide a high energy supply, contributing to a fast recovery of temperature and, consequently, to a high survival rate. This review aims to analyze the factors that affect thermoregulation of the newborn puppy, the physiological and behavioral responses, as well as to discuss the influence of the colostrum as an energy source and production of heat to face hypothermia, aside from discussing recent scientific findings of infrared thermography (IRT) used to assess the thermal response of the newborn puppy to cope with hypothermia.
Assuntos
Animais , Recém-Nascido , Cães , Colostro , Comportamento/fisiologia , Cães/crescimento & desenvolvimento , Homeostase/fisiologiaResumo
The present review aims to analyze the effect of extremely hot climates on the neurophysiological responses of thermal control and behavior in the river buffalo. Understanding thermal neuromodulation and its effects on the buffalo's behavior is of central importance, for this will allow us to make better decisions in terms of improving the level of welfare of buffaloes living in environments characterized by extreme heat, such as the humid tropics. The thermoregulation process involves a complex mechanism that begins with the integration of peripheral signals that are sent to the lateral parabrachial nucleus of the brainstem and then to the preoptic nucleus of the hypothalamus to generate physiological variations such as vasodilatation to dissipate heat under conditions of thermal stress, or vasoconstriction to conserve heat upon the perception of cold stimuli. The thermal biology of the river buffalo is based on several different adaptation mechanisms. The infrared thermography (IRT) technique will be of great help in this area because it permits the detection of vascular microcirculation changes in different thermal windows under adverse climatic conditions. Although buffaloes are classified as rustic animals, it is important to take into account their morpho-physiology and thermoregulation mechanisms to prevent thermal stress and the resulting poor welfare and reduced productivity. However, if appropriate thermoregulation facilities are provided (i.e., ponds, pools, potholes, or swampy areas), buffaloes can properly thermoregulate and tolerate high ambient temperatures. Therefore, they may represent a good option and an appropriate animal-based enterprise under climate change and global warming conditions.(AU)
Assuntos
Animais , Bovinos , Búfalos/fisiologia , Resposta ao Choque Térmico/fisiologia , Regulação da Temperatura Corporal/fisiologiaResumo
Mortality in piglets during the perinatal period, especially the first days after birth, is frequently caused by non infectious conditions, such as hypoglucemia or low birth weight, which can be associated with hypothermia experienced at birth. The thermal stability of newborn piglets is a fundamental aspect of neonatal care, so maintaining a constant, ideal temperature will substantially reduce newborn mortality. Species-specific characteristics, such as a limited capacity for thermoregulation, low energy reserves, a lack of brown adipose tissue (BAT) (-, and environmental conditions that are adverse for the piglet around the time of birth, including the absence of a microclimate, all of them contribute to difficulties in reaching thermal homeostasis in the first hours post-birth. Shivering thermogenesis and behavioral modifications to regulate body temperature through innate mechanisms allow animals to reduce their energy expenditures. Some body postures are effective in reducing contact with the floor and also nestling are useful to avoid heat loss, and also decreases heat dissipation. Achieving optimal development of thermoregulation is a challenge that newborns must confront to successfully adapt to extrauterine life. The objectives of this review, are to discuss the adverse factors that can lead to a death event due to hypothermia by analyzing the thermoregulation mechanisms at the central and cutaneous levels, also to analyze the harmful impacts that surviving neonate piglets confront in an unfavorable thermal environment, and to describe the pathophysiological mechanisms of death caused by hypothermia.(AU)
Assuntos
Animais , Recém-Nascido , Suínos/crescimento & desenvolvimento , Animais Recém-Nascidos , Mortalidade Perinatal , Hipotermia/mortalidade , Hipotermia/veterináriaResumo
Results on appropriate, inappropriate, and painful slaughtering methods of river buffalo (Bubalus bubalis) are discussed. Undesirable consequences of poor desensitization and/or slaughtering procedures, causing pain and suffering to animals, are also approached. These considerations are relevant as unsuitable methods can reduce consumer acceptance and commercial value of the meat obtained from animals undergoing deficient slaughtering procedures due to a lack of concern regarding their welfare. Relevant databases Scopus, Science Direct, and PubMedwere searched for this review, including keywords such as pain, slaughter, stunning, Bubalus bubalis, and animal welfare. A detailed description of river buffalo's encephalic anatomy was compared to cattle concerning correct stunning and slaughter methods. The neurobiological processes of pain felt by animals when inadequately desensitized was also examined. Finally, recent findings on stunning methods for buffaloes were discussed, including encephalography. It was concluded that different animal species may require different stunning methods; at the same time, the optimal anatomical site also varies between species. Therefore, it is of the utmost importance to train the personnel performing these procedures (transport, stunning, slaughtering) to avoid mishandling that jeopardizes animal welfare by generating stimuli that trigger neurophysiological responses and, in turn, translate into pain during slaughter and reduced meat quality.(AU)
Assuntos
Animais , Masculino , Feminino , Bovinos , Búfalos/anatomia & histologia , Nociceptividade/fisiologiaResumo
Results on appropriate, inappropriate, and painful slaughtering methods of river buffalo (Bubalus bubalis) are discussed. Undesirable consequences of poor desensitization and/or slaughtering procedures, causing pain and suffering to animals, are also approached. These considerations are relevant as unsuitable methods can reduce consumer acceptance and commercial value of the meat obtained from animals undergoing deficient slaughtering procedures due to a lack of concern regarding their welfare. Relevant databases Scopus, Science Direct, and PubMedwere searched for this review, including keywords such as pain, slaughter, stunning, Bubalus bubalis, and animal welfare. A detailed description of river buffalo's encephalic anatomy was compared to cattle concerning correct stunning and slaughter methods. The neurobiological processes of pain felt by animals when inadequately desensitized was also examined. Finally, recent findings on stunning methods for buffaloes were discussed, including encephalography. It was concluded that different animal species may require different stunning methods; at the same time, the optimal anatomical site also varies between species. Therefore, it is of the utmost importance to train the personnel performing these procedures (transport, stunning, slaughtering) to avoid mishandling that jeopardizes animal welfare by generating stimuli that trigger neurophysiological responses and, in turn, translate into pain during slaughter and reduced meat quality.(AU)
Assuntos
Animais , Masculino , Feminino , Bovinos , Búfalos/anatomia & histologia , Nociceptividade/fisiologiaResumo
Mortality in piglets during the perinatal period, especially the first days after birth, is frequently caused by non infectious conditions, such as hypoglucemia or low birth weight, which can be associated with hypothermia experienced at birth. The thermal stability of newborn piglets is a fundamental aspect of neonatal care, so maintaining a constant, ideal temperature will substantially reduce newborn mortality. Species-specific characteristics, such as a limited capacity for thermoregulation, low energy reserves, a lack of brown adipose tissue (BAT) (-, and environmental conditions that are adverse for the piglet around the time of birth, including the absence of a microclimate, all of them contribute to difficulties in reaching thermal homeostasis in the first hours post-birth. Shivering thermogenesis and behavioral modifications to regulate body temperature through innate mechanisms allow animals to reduce their energy expenditures. Some body postures are effective in reducing contact with the floor and also nestling are useful to avoid heat loss, and also decreases heat dissipation. Achieving optimal development of thermoregulation is a challenge that newborns must confront to successfully adapt to extrauterine life. The objectives of this review, are to discuss the adverse factors that can lead to a death event due to hypothermia by analyzing the thermoregulation mechanisms at the central and cutaneous levels, also to analyze the harmful impacts that surviving neonate piglets confront in an unfavorable thermal environment, and to describe the pathophysiological mechanisms of death caused by hypothermia.
Assuntos
Animais , Recém-Nascido , Animais Recém-Nascidos , Hipotermia/mortalidade , Hipotermia/veterinária , Mortalidade Perinatal , Suínos/crescimento & desenvolvimentoResumo
The present review aims to analyze the effect of extremely hot climates on the neurophysiological responses of thermal control and behavior in the river buffalo. Understanding thermal neuromodulation and its effects on the buffalo's behavior is of central importance, for this will allow us to make better decisions in terms of improving the level of welfare of buffaloes living in environments characterized by extreme heat, such as the humid tropics. The thermoregulation process involves a complex mechanism that begins with the integration of peripheral signals that are sent to the lateral parabrachial nucleus of the brainstem and then to the preoptic nucleus of the hypothalamus to generate physiological variations such as vasodilatation to dissipate heat under conditions of thermal stress, or vasoconstriction to conserve heat upon the perception of cold stimuli. The thermal biology of the river buffalo is based on several different adaptation mechanisms. The infrared thermography (IRT) technique will be of great help in this area because it permits the detection of vascular microcirculation changes in different thermal windows under adverse climatic conditions. Although buffaloes are classified as rustic animals, it is important to take into account their morpho-physiology and thermoregulation mechanisms to prevent thermal stress and the resulting poor welfare and reduced productivity. However, if appropriate thermoregulation facilities are provided (i.e., ponds, pools, potholes, or swampy areas), buffaloes can properly thermoregulate and tolerate high ambient temperatures. Therefore, they may represent a good option and an appropriate animal-based enterprise under climate change and global warming conditions.
Assuntos
Animais , Bovinos , Búfalos/fisiologia , Regulação da Temperatura Corporal/fisiologia , Resposta ao Choque Térmico/fisiologiaResumo
Results on appropriate, inappropriate, and painful slaughtering methods of river buffalo (Bubalus bubalis) are discussed. Undesirable consequences of poor desensitization and/or slaughtering procedures, causing pain and suffering to animals, are also approached. These considerations are relevant as unsuitable methods can reduce consumer acceptance and commercial value of the meat obtained from animals undergoing deficient slaughtering procedures due to a lack of concern regarding their welfare. Relevant databases Scopus, Science Direct, and PubMed were searched for this review, including keywords such as pain, slaughter, stunning, Bubalus bubalis, and animal welfare. A detailed description of river buffalo's encephalic anatomy was compared to cattle concerning correct stunning and slaughter methods. The neurobiological processes of pain felt by animals when inadequately desensitized was also examined. Finally, recent findings on stunning methods for buffaloes were discussed, including encephalography. It was concluded that different animal species may require different stunning methods; at the same time, the optimal anatomical site also varies between species. Therefore, it is of the utmost importance to train the personnel performing these procedures (transport, stunning, slaughtering) to avoid mishandling that jeopardizes animal welfare by generating stimuli that trigger neurophysiological responses and, in turn, translate into pain during slaughter and reduced meat quality.
Assuntos
Masculino , Feminino , Animais , Bovinos , Búfalos/anatomia & histologia , Nociceptividade/fisiologiaResumo
The facial expressions of animals constitute a means of manifesting emotions, fulfilling functions related to social interactions in several species. Interest has come to use facialexpressions as a tool for predicting intentions; in the case of aggression, for example, impeding attacks between individuals prevents negative economic and emotional impacts. Recent research has sought to associate facial expressions with painful events as tail-cropping and castration on the assumption thatobjective evaluations of the presence or absence of grimaces in pigs' snouts may allow us to determine the intensity of the pain they perceive. Furthermore, to continue developing scales that will complement the existing piglet grimace scale (PGS), which is not yet fully-validated in terms of reliability. Another area of research is interpreting expressions of fear during traumatic events like pre-slaughter handling. Also, the phenomenon of emotional contagion in groups of animals suggests the need to focus on their emotions, since recognizing them could allow us to prevent alterations of meat quality.These approaches reveal the need for a detailed compilation of the facial expressions of pigs based on current scientific literature regarding emotions, alimentation, and pain-related behavioral responses in pigs.(AU)
Assuntos
Animais , Suínos/fisiologia , Suínos/psicologia , Comportamento Animal , Medo/psicologia , Dor/psicologia , Dor/veterináriaResumo
The objective of this review article is to discuss and analyze the most important scientific findings from studies of vascular microcirculation in the river buffalo using infrared thermography (IRT), as well as the thermal windows utilizedwith this species. The goals are to define the scope and areas of opportunity for IRT use in evaluating physiological processes and identifying potential applications in reproductive events associated with andrological traits inmales and the detection of estrus and udder health in females. IRT has allowed the development of diverse perspectives regarding the comparative physiology of events likethermogenesis, peripheral blood flow, respiratory physiology, and mechanisms that reduce body temperature. The case of the river buffalo is no exception. According to the information analyzed, the temperatures of the orbital area, muzzle, andvulva have proven efficient for evaluating thermal comfort, a particularly important aspect of this species given its limited thermoregulating capacity and constant exposure to extremetemperatures. Evaluating scrotal temperature has been revealed as an appropriate tool for evaluating semen quality, while the surface temperature of the udder is useful in assessing mammary development in female buffaloes, two aspects of great zootechnical importance. In future studies, IRT will play a fundamental role in enhancing our understanding of the river buffalo's mechanisms of vascular microcirculation, with applications in productivity and behavior.(AU)
Assuntos
Animais , Masculino , Feminino , Bovinos , Temperatura Corporal/fisiologia , Termografia/tendências , Termografia/veterinária , Búfalos/fisiologia , Resposta ao Choque Térmico/efeitos da radiaçãoResumo
This review aims to analyze and contrast the neurological effects associated with the use of caffeine on neurobehavior and neuroprotection in animal models. Caffeine belongs to the group of methylxanthines that exert a direct effect on adenosine receptors associated with inhibitory or excitatory G proteins, generating modification of cyclic AMP activity and intracellular calcium flow which produces alterations in the modulation system of the neurotransmitters dopamine and glutamate. The regulation of the neurotransmission systems generates protection against the inflammation of the central nervous system, by activation of the microglia and reinforcement of the blood-brain barrier. This drug will also restore cognition or prevent memory loss in Parkinson's or Alzheimer's diseases. It is important to establish new study models in other species to assess whether the behavior of the molecule is similar and to obtain other clinical applications in its behavioral and neuroprotective effects.(AU)
Assuntos
Animais , Hipotálamo/efeitos dos fármacos , Hipotálamo/fisiopatologia , Estimulantes do Sistema Nervoso Central/análise , Estimulantes do Sistema Nervoso Central/farmacologia , Estimulantes do Sistema Nervoso Central/uso terapêutico , Cafeína , Doenças NeurodegenerativasResumo
This review aims to analyze and contrast the neurological effects associated with the use of caffeine on neurobehavior and neuroprotection in animal models. Caffeine belongs to the group of methylxanthines that exert a direct effect on adenosine receptors associated with inhibitory or excitatory G proteins, generating modification of cyclic AMP activity and intracellular calcium flow which produces alterations in the modulation system of the neurotransmitters dopamine and glutamate. The regulation of the neurotransmission systems generates protection against the inflammation of the central nervous system, by activation of the microglia and reinforcement of the blood-brain barrier. This drug will also restore cognition or prevent memory loss in Parkinson's or Alzheimer's diseases. It is important to establish new study models in other species to assess whether the behavior of the molecule is similar and to obtain other clinical applications in its behavioral and neuroprotective effects.
Assuntos
Animais , Estimulantes do Sistema Nervoso Central/análise , Estimulantes do Sistema Nervoso Central/farmacologia , Estimulantes do Sistema Nervoso Central/uso terapêutico , Hipotálamo/efeitos dos fármacos , Hipotálamo/fisiopatologia , Cafeína , Doenças NeurodegenerativasResumo
The objective of this review article is to discuss and analyze the most important scientific findings from studies of vascular microcirculation in the river buffalo using infrared thermography (IRT), as well as the thermal windows utilizedwith this species. The goals are to define the scope and areas of opportunity for IRT use in evaluating physiological processes and identifying potential applications in reproductive events associated with andrological traits inmales and the detection of estrus and udder health in females. IRT has allowed the development of diverse perspectives regarding the comparative physiology of events likethermogenesis, peripheral blood flow, respiratory physiology, and mechanisms that reduce body temperature. The case of the river buffalo is no exception. According to the information analyzed, the temperatures of the orbital area, muzzle, andvulva have proven efficient for evaluating thermal comfort, a particularly important aspect of this species given its limited thermoregulating capacity and constant exposure to extremetemperatures. Evaluating scrotal temperature has been revealed as an appropriate tool for evaluating semen quality, while the surface temperature of the udder is useful in assessing mammary development in female buffaloes, two aspects of great zootechnical importance. In future studies, IRT will play a fundamental role in enhancing our understanding of the river buffalo's mechanisms of vascular microcirculation, with applications in productivity and behavior.
Assuntos
Masculino , Feminino , Animais , Bovinos , Búfalos/fisiologia , Resposta ao Choque Térmico/efeitos da radiação , Temperatura Corporal/fisiologia , Termografia/tendências , Termografia/veterináriaResumo
The facial expressions of animals constitute a means of manifesting emotions, fulfilling functions related to social interactions in several species. Interest has come to use facialexpressions as a tool for predicting intentions; in the case of aggression, for example, impeding attacks between individuals prevents negative economic and emotional impacts. Recent research has sought to associate facial expressions with painful events as tail-cropping and castration on the assumption thatobjective evaluations of the presence or absence of grimaces in pigs' snouts may allow us to determine the intensity of the pain they perceive. Furthermore, to continue developing scales that will complement the existing piglet grimace scale (PGS), which is not yet fully-validated in terms of reliability. Another area of research is interpreting expressions of fear during traumatic events like pre-slaughter handling. Also, the phenomenon of emotional contagion in groups of animals suggests the need to focus on their emotions, since recognizing them could allow us to prevent alterations of meat quality.These approaches reveal the need for a detailed compilation of the facial expressions of pigs based on current scientific literature regarding emotions, alimentation, and pain-related behavioral responses in pigs.