Application of Infrared Thermography in the Rehabilitation of Patients in Veterinary Medicine.

Infrared Thermography (IRT) has become an assistance tool in medicine and is used to noninvasively evaluate heat elimination during and after inflammatory processes or during the recovery period. However, its application in veterinary patients undergoing physiotherapy is a field that requires deep research. This review aims to analyze the application of IRT in the monitoring of animal physiotherapy, using the thermal changes that are present in patients undergoing gait or lameness issues (e.g., inflammation, pain, increased local temperature) as a neurobiological basis. Rehabilitation techniques such as acupuncture, physical therapies, thermotherapy, photo-biomodulation, and electrostimulation have been reported to have an anti-inflammatory effect that decreases the amount of local heat production, which is heat that can be recorded with IRT. Therefore, IRT could be used as a complementary tool to evaluate the effectiveness of the therapy, and it is suggested that further studies evaluate the accuracy, sensibility, and sensitivity of IRT.

Correlation of Blood Hemoglobin Values with Non-Invasive Co-Oximetry Measurement of SpHb in Dogs Undergoing Elective Ovariohysterectomy.

Cardiovascular function monitoring has been suggested as a key parameter to determine patient stability during the anesthetic process. However, the use of pulse co-oximetry has been suggested as a technology to complement the monitoring of this system as a direct way to assess hemoglobin (Hb) blood concentration. Therefore, this study aimed to correlate and determine the measurement bias between Hb blood levels with continuously determined blood hemoglobin concentration (SpHb) and arterial oxygen content values (SpOC), both obtained by noninvasive co-oximetry in dogs undergoing elective ovariohysterectomy (OVH). A total of 85 clinically healthy bitches of different breeds that were admitted for elective OVH surgery were evaluated. These animals underwent SpHb and SpOC capture after the in vivo setting for the duration of the surgical procedure. Likewise, five minutes before the end of the surgical procedure, a blood sample was obtained directly from the jugular vein to determine the blood concentration of Hb (HbLAB). The Bland-Altman analysis showed 95% limits of agreement from -4.22 to 4.99 g/dL with a BIAS (mean difference) of 0.384 ± 2.35 g/dL (r = 0.401). SpHb recordings were correlated with oxygen saturation (SpO2) (r = 0.995), SpOC (r = 0.992) and with perfusion index (PI) (r = 0.418). Therefore, SpHb presents a moderate positive correlation with direct blood concentration of Hb. This possibly shows that continuous measurement of SpHb by noninvasive co-oximetry is a reliable and advanced alternative for monitoring Hb concentration in dogs under anesthesia.

Hypothalamic Neuromodulation of Hypothermia in Domestic Animals.

When an organism detects decreases in their core body temperature, the hypothalamus, the main thermoregulatory center, triggers compensatory responses. These responses include vasomotor changes to prevent heat loss and physiological mechanisms (e.g., shivering and non-shivering thermogenesis) for heat production. Both types of changes require the participation of peripheral thermoreceptors, afferent signaling to the spinal cord and hypothalamus, and efferent pathways to motor and/or sympathetic neurons. The present review aims to analyze the scientific evidence of the hypothalamic control of hypothermia and the central and peripheral changes that are triggered in domestic animals.

Utilization of Infrared Thermography in Assessing Thermal Responses of Farm Animals under Heat Stress.

Heat stress is a condition that can affect the health, performance, and welfare of farm animals. The perception of thermal stress leads to the activation of the autonomic nervous system to start a series of physiological and behavioral mechanisms to restore thermostability. One of these mechanisms is vasodilation of peripheral blood vessels to increase heat loss through the skin. Due to this aspect, infrared thermography has been suggested as a method to assess the thermal state of animals and predict rectal temperature values noninvasively. However, it is important to consider that predicting rectal temperature is challenging, and its association with IRT is not always a direct linear relationship. The present review aims to analyze the neurobiological response associated with heat stress and how thermal imaging in different thermal windows can be used to recognize heat stress in farmed ungulates.

Uterine dynamics, blood profiles, and electronic fetal monitoring of primiparous and multiparous bitches classified according to their weight.

Perinatal mortality occurs in all species. In dogs, mortality rates have been reported to range from 5 to 35%. Electronic fetal and uterine monitoring has recently been used in domestic animals to monitor the mother and newborn before and during parturition. In this way, the fetal heart rate and uterine dynamics can be monitored. This study evaluated the uterine dynamics of bitches with different weights and parity. Ninety-six bitches and their 476 puppies were divided into four experimental groups containing 24 individuals each (12 primiparous bitches and 12 multiparous bitches), according to body weight: G1 (4-8 kg), G2 (8.1-16 kg), G3 (16.1 to 32 kg), and G4 (32.1 to 39.6 kg). The fetal heart rate decelerations (dip 2 patterns), uterine dynamics, and bitches' blood profiles were evaluated, including levels of glucose, lactate, pCO2, pO2, pH, HCO3-, and Ca++. The dam weight can affect the vitality of newborns and the uterine dynamics, with differences in the frequency, intensity, and duration of myometrial contractions. The expulsion interval between puppies was longest in primiparous bitches with low weight and shortest in multiparous bitches with high weight. The expulsion interval and the number of stillborn females were higher in primiparous bitches with high weight. Newborn male puppies were significantly heavier than newborn females.

Caffeine Administration in Piglets with Low Birthweight and Low Vitality Scores, and Its Effect on Physiological Blood Profile, Acid-Base Balance, Gas Exchange, and Infrared Thermal Response.

Intrapartum asphyxia, fetal hypoxia, and their consequences (e.g., acidosis, hypercapnia, hypoglycemia, and hypothermia) are the main factors related to physio-metabolic imbalances that increase neonatal mortality in piglets, particularly in piglets with low birthweight and low vitality scores. This study aimed to evaluate the effect of three different doses of caffeine (10, 20, and 30 mg/kg) administered orally to 480 newborn piglets with low birthweight and low vitality scores. Blood gas parameters (pH, pO2, pCO2, and HCO3-), physio-metabolic profile (Ca++, glucose, and lactate), and the thermal response assessed through infrared thermography in four thermal windows (ocular, auricular, snout, and hindlimb) and rectal temperature were evaluated during the first 24 h of life. Doses of 30 mg/kg resulted in significant differences at 24 h for all evaluated parameters, suggesting that caffeine administration improved the cardiorespiratory function and metabolic activity of piglets by reducing acidosis, restoring glycemia, and increasing surface and rectal temperature. In conclusion, caffeine at 30 mg/kg could be suggested as an appropriate dose to use in piglets with low birthweight and low vitality scores. Future research might need to study the presentation of adverse effects due to higher caffeine concentrations.

Rat Grimace Scale as a Method to Evaluate Animal Welfare, Nociception, and Quality of the Euthanasia Method of Wistar Rats.

Refinement of experimental procedures in animal research has the objective of preventing and minimizing pain/distress in animals, including the euthanasia period. This study aimed to evaluate pain associated with six methods of euthanasia in Wistar rats (injectable, inhalational, and physical), by applying the Rat Grimace Scale (RGS), comparing the scores, and determining the method with the highest score that might indicate pain for laboratory rodents. Sixty adult male and female Wistar rats were used and assigned to six treatments: pentobarbital, CO2, decapitation, isoflurane, ketamine + xylazine, and ketamine + CO2. Video recording to assess the RGS scores was performed in four events: basal: 24 h before the procedure; Ti1: three minutes before the procedure; Ti2: during the application of the euthanasia method; and Ti3: immediately after the application until LORR. The main findings of this study showed that, during Ti2, decapitation and ketamine + xylazine had the highest scores (0.6 ± 0.26 and 0.6 ± 0.16, respectively) (p < 0.0001), while at Ti3, CO2 (0.9 ± 0.18) and isoflurane (1.2 ± 0.20) recorded the highest scores (p < 0.0001). According to the present results, decapitation and ketamine + xylazine elicited short-term acute pain, possibly due to tissue damage caused by both methods (injection and guillotine). In contrast, isoflurane's RGS scores recorded during Ti3 might be associated with nociception/pain due to the pungency of the drug or to the pharmacological muscle relaxant effect of isoflurane. Further research is needed to establish a comprehensive study of pain during euthanasia, where RGS could be used minding the limitations that anesthetics might have on facial expression.

Thermal Balance in Male Water Buffaloes Transported by Long and Short Journeys.

Transport is a stressor that can cause physiological and metabolic imbalances in livestock, resulting in stress-induced hyperthermia. In water buffaloes, studies regarding the thermal state of animals during mobilization are scarce. Therefore, this study aimed to compare the thermal response of 1516 water buffaloes using infrared thermography (IRT) during 15 short trips (783 animals, 60,291 records, average duration = 50.33 min ± 5.48 min) and 14 long trips (733 animals, 56,441 records, average duration = 13.31 h ± 47.32 min). The surface temperature was assessed in 11 regions (periocular, lacrimal caruncle, nasal, lower eyelid, auricular, frontal-parietal, pelvic limb, torso, abdominal, lumbar, and thoracic) during seven phases from pasture to post-transport. It was found that the surface temperature of the periocular, lacrimal caruncle, nasal, auricular, frontal-parietal, pelvic limb, torso, abdominal, lumbar, and thoracic regions was significantly higher during SJs (+3 °C) when compared to LJs (p < 0.0001). In particular, the frontal-parietal region had a significant increase of 10 °C during the post-transport phase (p < 0.0001) in both groups, recording the highest temperatures during this phase. Likewise, a strong positive significant correlation between the different regions was found (r = 0.90, p < 0.0001). It is worth mentioning that the herding, loading, pre-, and post-transport phases were the ones where the greatest thermal response was recorded, possibly due to the influence of human interaction. Finally, a strong positive correlation (r above 0.9, p > 0.001) between the periocular, lacrimal caruncle, pinna, and pelvic limb was found. According to the results, SJ could be considered a stressful event that hinders thermal generation, contrarily to LJ.

The Challenge of Global Warming in Water Buffalo Farming: Physiological and Behavioral Aspects and Strategies to Face Heat Stress.

Water buffaloes have morphological and behavioral characteristics for efficient thermoregulation. However, their health, welfare, and productive performance can be affected by GW. The objective of this review was to analyze the adverse effects of GW on the productive behavior and health of water buffaloes. The physiological, morphological, and behavioral characteristics of the species were discussed to understand the impact of climate change and extreme meteorological events on buffaloes' thermoregulation. In addition, management strategies in buffalo farms, as well as the use of infrared thermography as a method to recognize heat stress in water buffaloes, were addressed. We concluded that heat stress causes a change in energy mobilization to restore animal homeostasis. Preventing hyperthermia limits the physiological, endocrine, and behavioral changes so that they return to thermoneutrality. The use of fans, sprinklers, foggers, and natural sources of water are appropriate additions to current buffalo facilities, and infrared thermography could be used to monitor the thermal states of water buffaloes.

Cardiorespiratory and Neuroprotective Effects of Caffeine in Neonate Animal Models.

Caffeine is widely used to improve neonatal health in animals with low vitality. Due to its pharmacokinetics and pharmacodynamics, caffeine stimulates the cardiorespiratory system by antagonism of adenosine receptors and alteration in Ca+2 ion channel activity. Moreover, the availability of intracellular Ca+2 also has positive inotropic effects by increasing heart contractibility and by having a possible positive effect on neonate vitality. Nonetheless, since neonatal enzymatic and tissular systems are immature at birth, there is a controversy about whether caffeine is an effective therapy for newborns. This review aims to analyze the basic concepts of caffeine in neonatal animal models (rat and mouse pups, goat kids, lambs, and piglets), and it will discuss the neuroprotective effect and its physiological actions in reducing apnea in newborns.

Thermal Response of Laboratory Rats (Rattus norvegicus) during the Application of Six Methods of Euthanasia Assessed by Infrared Thermography.

Refinement is one of the principles aiming to promote welfare in research animals. The techniques used during an experimental protocol, including euthanasia selection, must prevent and minimize suffering. Although the current euthanasia methods applied to laboratory rodents are accepted, the controversial findings regarding the potential stress/distress they can cause is a field of research. The objective was to assess the thermal response of Wistar rats during various euthanasia methods using infrared thermography (IRT) to determine the method that prevents or diminishes the stress response and prolonged suffering. Pentobarbital (G1), CO2 (G2), decapitation (G3), isoflurane (G4), ketamine + xylazine (G5), and ketamine + CO2 (G6) were evaluated at five evaluation times with IRT to identify changes in the surface temperature of four anatomical regions: ocular (T°ocu), auricular (T°ear), interscapular (T°dor), and caudal (T°tai). Significant differences (p < 0.05) were found in G2 and G4, registering temperature increases from the administration of the drug to the cessation of respiratory rate and heart rate. Particularly, isoflurane showed a marked thermal response in T°ocu, T°ear, T°dor, and T°tai, suggesting that, in general, inhalant euthanasia methods induce stress in rats and that isoflurane might potentially cause distress, an effect that must be considered when deciding humane euthanasia methods in laboratory rodents.

Slaughtering of Water Buffalo (Bubalus bubalis) with and without Stunning: A Focus on the Neurobiology of Pain, Hyperalgesia, and Sensitization.

The slaughter process in livestock is considered a stressor where the transport and handling of animals, as well as the selected stunning and bleeding methods, can cause acute pain, distress, and suffering. In water buffaloes, although stunning is known to be performed before bleeding to induce unconsciousness, no emphasis is made on the nociceptive events during this process. Particularly, current mechanical stunning methods applied to cattle are unsuitable for water buffaloes due to anatomical differences in the skull from other large ruminants. Furthermore, although very high-pressure pneumatic (200-220 psi) may be effective in the frontal position for lighter-weight water buffalos, for heavier animals, it is less likely to be effective. The present review aims: (1) to analyze the anatomical particularities of water buffaloes to discuss the importance of selecting a stunning method suitable for buffaloes, and (2) to revise the potential pain-related consequences, such as hyperalgesia and sensitization, and the signs to assess the stun quality and death to comprehend the relevance of a proper technique according to the species.

Assessment of Vitality, Blood Profile, and Degree of Meconium Staining on the Skin in Newborn Dogs According to Its Birth Weight.

Neonatal mortality in dogs reaches up to 40%. Due to the high rates, promptly detecting the causes and preventing newborns from dying are extremely important. Vitality evaluation, blood parameters, and the degree of meconium staining on the skin are valuable resources in canine perinatology. In this study, 435 puppies from 85 bitches close to parturition were recruited and divided into four quartiles according to the puppy's birth weight: Q1 (127-200 g) n = 110 puppies, Q2 (201-269 g) n = 108 puppies, Q3 (270-388 g) n = 108 puppies, and Q4 (389-464 g) n = 109 puppies. This experimental article aimed to report the effect of birth weight on the blood profile variables, the vitality of newborn puppies, and the meconium staining degree, integrating these three aspects. It was concluded that the weight of newborns was correlated with the degree of meconium staining, presenting more cases of severe meconium staining in the puppies of the highest birth weight group. The weight of the newborns was correlated with a higher number of stillbirths and alterations in the blood variables, showing the most severe cases of metabolic acidosis, hypoxia, and hypoglycemia in the puppies of the Q4 quartile. On the contrary, no statistically significant correlations were found between the weight of newborns and vitality. Nevertheless, the analysis of the results showed that the most vigorous puppies were found at Q1; however, at minute 60 after birth (AB), all the puppies in the four quartiles standardized their vitality scores.

Assessment of Pain and Inflammation in Domestic Animals Using Infrared Thermography: A Narrative Review.

Pain assessment in domestic animals has gained importance in recent years due to the recognition of the physiological, behavioral, and endocrine consequences of acute pain on animal production, welfare, and animal model validity. Current approaches to identifying acute pain mainly rely on behavioral-based scales, quantifying pain-related biomarkers, and the use of devices monitoring sympathetic activity. Infrared thermography is an alternative that could be used to correlate the changes in the superficial temperature with other tools and thus be an additional or alternate acute pain assessment marker. Moreover, its non-invasiveness and the objective nature of its readout make it potentially very valuable. However, at the current time, it is not in widespread use as an assessment strategy. The present review discusses scientific evidence for infrared thermography as a tool to evaluate pain, limiting its use to monitor acute pain in pathological processes and invasive procedures, as well as its use for perioperative monitoring in domestic animals.

The Role of Brown Adipose Tissue and Energy Metabolism in Mammalian Thermoregulation during the Perinatal Period.

Hypothermia is one of the most common causes of mortality in neonates, and it could be developed after birth because the uterus temperature is more elevated than the extrauterine temperature. Neonates use diverse mechanisms to thermoregulate, such as shivering and non-shivering thermogenesis. These strategies can be more efficient in some species, but not in others, i.e., altricials, which have the greatest difficulty with achieving thermoneutrality. In addition, there are anatomical and neurological differences in mammals, which may present different distributions and amounts of brown fat. This article aims to discuss the neuromodulation mechanisms of thermoregulation and the importance of brown fat in the thermogenesis of newborn mammals, emphasizing the analysis of the biochemical, physiological, and genetic factors that determine the distribution, amount, and efficiency of this energy resource in newborns of different species. It has been concluded that is vital to understand and minimize hypothermia causes in newborns, which is one of the main causes of mortality in neonates. This would be beneficial for both animals and producers.

Controversial Topics in Animal Welfare in Latin America: A Focus on the Legislation Surrounding the Human-Companion Animal Relationship and Animals Used for Recreational Practices.

Animal welfare is a societally relevant issue that is globally attracting increased attention. This is in addition to the importance placed on welfare for the animals themselves. However, the content and application of laws protecting animals' welfare vary across countries. In Latin America, there are a range of common practices or activities involving certain animal species, many of which are legal, that can impair an animal's quality of life. These include the performance of aesthetic surgical procedures; bull-, cock-, and dog fighting; and the existence of circuses that exhibit animals. The extent and impact of these practices being dependent on the socioeconomic, cultural, territorial, and regulatory landscape of each country. Particularly, Ibero-American regions face welfare challenges that might be influenced by traditions and relevant legal gaps. The objective of this article is to review controversial practices carried out in companion and entertainment animals in Latin America, with a focus on legal aspects, as well as the current efforts being made to address and incorporate global welfare standards into domestic and wild animal practice and regulation.

Assessment of thermal changes in water buffalo mobilized from the paddock and transported by short journeys.

Evaluating the welfare of buffaloes during transport is key to obtaining and commercializing high-quality meat products; however, effective assessments require recognizing several stressors that activate physiological mechanisms that can have repercussions on the health and productive performance of species. The aim of this study was to evaluate the surface temperatures of different body and head regions in this species during events prior, and posterior, to transport for short periods; that is, from paddock to loading. The second goal was to determine the level of correlation between thermal windows. This study used infrared thermography (IRT) to evaluate the surface temperature of 624 water buffaloes (Buffalypso breed) during 12 short trips (average duration = 2 h ± 20 min) by focusing on 11 regions of the body (Regio corporis), in the head regions (Regiones capitis) the face regions (Regiones faciei), Orbital region (Regio orbitalis) with special attention to structures such as the lacrimal caruncle, periocular area and lower eyelid (Regio palpebralis inferior); nasal region (Regio nasalis) with special attention to nostril thermal window; and regions of the skull (Regiones cranii) such as auricular region (Regio auricularis) with special attention to auditory canal and frontal-parietal region (Regio frontalis-parietalis) and trunk region (Truncus regionis) such as thoracic and abdominal regions, regions of the vertebral column (Columna vertebralis) with the thoracic vertebral region (Regio vertebralis thoracis) and lumbar region (Regio lumbalis); and regions of the pelvis limb (Regiones membri pelvini). Recordings were made during seven phases: paddock (P1), herding (P2), corral (P3), chute handling (P4), shipping (P5), pre- (P6), and post-transport (P7). A total of 48,048 readings were obtained from 11 thermal windows. The results showed that the surface temperatures of the windows increased by as much as 5°C during P2, P3, P5, P6, and P7 compared to P1 and P4 (p < 0.0001). Differences of at least 1°C were also observed between thermal windows in the craniofacial, lateral corporal, and peripheral zones (p < 0.0001). Finally, a strong positive correlation (r = 0.9, p < 0.0001) was found between the thermal windows. These findings lead to the conclusion that the surface temperature of the craniofacial and corporal regions of buffaloes transported for short periods varied in relation to the phase of mobilization (from paddock to post-transport), likely as a response to stressful factors, since herding and loading increased the thermal values in each window. The second conclusion is that there are strong positive correlations between central and peripheral thermal windows.

The Role of Oxytocin in Domestic Animal's Maternal Care: Parturition, Bonding, and Lactation.

Oxytocin (OXT) is one of the essential hormones in the birth process; however, estradiol, prolactin, cortisol, relaxin, connexin, and prostaglandin are also present. In addition to parturition, the functions in which OXT is also involved in mammals include the induction of maternal behavior, including imprinting and maternal care, social cognition, and affiliative behavior, which can affect allo-parental care. The present article aimed to analyze the role of OXT and the neurophysiologic regulation of this hormone during parturition, how it can promote or impair maternal behavior and bonding, and its importance in lactation in domestic animals.

The Importance of Animal Models in Biomedical Research: Current Insights and Applications.

Animal research is considered a key element in advance of biomedical science. Although its use is controversial and raises ethical challenges, the contribution of animal models in medicine is essential for understanding the physiopathology and novel treatment alternatives for several animal and human diseases. Current pandemics' pathology, such as the 2019 Coronavirus disease, has been studied in primate, rodent, and porcine models to recognize infection routes and develop therapeutic protocols. Worldwide issues such as diabetes, obesity, neurological disorders, pain, rehabilitation medicine, and surgical techniques require studying the process in different animal species before testing them on humans. Due to their relevance, this article aims to discuss the importance of animal models in diverse lines of biomedical research by analyzing the contributions of the various species utilized in science over the past five years about key topics concerning human and animal health.

Euthanasia and Pain in Canine Patients with Terminal and Chronic-Degenerative Diseases: Ethical and Legal Aspects.

Euthanasia is commonly performed in veterinary medicine to humanely induce the death of an animal when its quality of life is affected by pain or chronic degenerative diseases. The choice of euthanasia is a bilateral decision that represents a challenge for both the veterinarian and the owner of the animal due to the close emotional human-animal bond. Currently, there is legislation that can orient veterinarians concerning euthanasia and the causes that would justify this resolution. However, it is still controversial, and deciding it as the last available resort requires considering it from a medical, legal, and moral perspective. Therefore, this review aims to explore the ethical and legal implications of euthanasia in canine patients. It will analyze the reason that can justify euthanasia in animals with pain or terminal and chronic degenerative diseases, highlighting the importance of effective communication, ethical knowledge, and consideration of euthanasia as a multimodal resolution.