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.

Is the Weight of the Newborn Puppy Related to Its Thermal Balance?

Hypothermia, a factor associated with neonatal mortality, can occur immediately after birth as a protective mechanism to prevent hypoxic damage in neonates, or to reduce the metabolic rate to improve the chances of survival in the first hours of life. The heat interchange through the superficial temperature of animals can be evaluated with infrared thermography (IRT). However, to date, there is no information on thermal windows in puppies. This study aimed to evaluate, with the use of IRT, the microcirculatory alterations in 8 different thermal windows identified at 7 different times in 289 newborn puppies assigned to different groups. Three thermograms were taken from four zones of each puppy: the facial, frontal, right lateral, and left lateral regions. Newborn puppies were grouped in 4 quartiles according to their weight: Q1 (126−226 g) n = 73, Q2 (227−330 g) n = 72, Q3 (331−387 g) n = 74, and Q4 (388−452 g) n = 70. A total of 8 thermal windows were considered at 7 evaluation times from Wet at birth until 24 h after birth (AB). Two-way mixed ANOVA within and between subjects' design for each thermal window (eight models) was performed. Results revealed a positive correlation between the puppy's weight and its ability to achieve thermostability in all the evaluated thermal windows. Statistically significant differences (p < 0.0001) between the 4 quartiles (Q1, Q2, Q3, and Q4) were found. The lowest temperatures were recorded when the pups were still wet and the highest at 24 h AB. Thermal windows with the highest temperatures were abdominal (34.234 ± 0.056 °C), thoracic (33.705 ± 0.049 °C), nasal (30.671 ± 0.110 °C), and upper left palpebral (34.066 ± 0.052 °C), while the lowest were thoracic limb brachial biceps (27.534 ± 0.051 °C), thoracic limb elbow (27.141 ± 0.049 °C), thoracic limb metacarpal (27.024 ± 0.062 °C), and femoral pelvic limb (27.654 ± 0.055 °C). Assessing the thermal response in newborn puppies can help identify drastic temperature reductions or deficient thermoregulatory compensation during the first hours of life, preventing the consequences of hypothermia.

Relation between the Dam's Weight on Superficial Temperature of Her Puppies at Different Stages of the Post-Partum.

The thermal stability of newborns is an essential parameter that can be recorded to evaluate neonatal care. Knowing the thermal windows to evaluate and maintain a constant temperature helps significantly reduce neonatal mortality. This study aimed to assess the superficial temperature alterations in the distinct thermal windows of puppies with mothers of diverse weights and their repercussions. We evaluated the superficial temperature using infrared thermography at eight thermal windows and seven different times: when wet due to the fetal fluid immediately after birth until 24 h of life in newborn puppies from bitches divided into four bodyweight groups. The results revealed a positive correlation between the dam's weight and the ability to achieve thermostability in the newborn puppies in all the evaluated thermal windows. The time effect showed the lowest temperatures when the puppies were still wet, a gradual increase, and the highest temperature at 24 h after birth. The thermal windows with the highest temperatures were abdominal, thoracic, nasal, and upper left palpebral, and those with the lowest were the thoracic limb brachial biceps, thoracic limb elbow, metacarpal, and femoral pelvic limb. A significant increase in the temperatures in the thermal windows of the abdominal, thoracic, and upper left palpebral immediately after ingesting colostrum was observed. The weight of the dams is an important factor that positively intervenes in the thermoregulatory capacity of the puppies, especially when newborns are dry and have been passed 24 h after birth.

Early Blood Analysis and Gas Exchange Monitoring in the Canine Neonate: Effect of Dam's Size and Birth Order.

In canines, size at birth is determined by the dam's weight, which would probably affect the newborn's viability due to litter size and birth order. Fetal hypoxia causes distress and acidemia. Identifying physiological blood alterations in the puppy during the first minute of life through the blood gas exchange of the umbilical cord could determine the puppy's risk of suffering asphyxiation during labor. This study aimed to evaluate the effect of the birth order and dam's size during spontaneous labor and the alterations during the first minute of life. The results indicate that the dam's size and the birth order have considerable physiological and metabolic effects in the puppies, mainly in birth order 1 (BO1) in small-size dogs, while in the medium size, the last puppy presented more alterations, probably because of a prolonged whelping which could have fostered hypoxic processes and death. Likewise, with large-size dogs, intrapartum asphyxiation processes were registered during the first minute of life in any birth order.

Blood Biomarker Profile Alterations in Newborn Canines: Effect of the Mother's Weight.

This study aims to determine the effect of the weight of bitches on liveborn and stillbirth puppies from eutocic births, and physiological blood alterations during the first minute postpartum. A total of 52 female dogs were evaluated and distributed in four categories: C1 (4.0-8.0 kg, n = 19), C2 (8.1-16.0 kg, n = 16), C3 (16.1-32.0 kg, n = 11), and C4 (32.1-35.8 kg, n = 6). The dams produced 225 liveborn puppies and 47 were classified as stillbirth type II. Blood samples were taken from the umbilical vein to evaluate the concentration of gases, glucose, lactate, calcium, hematocrit levels, and blood pH. The liveborn puppies in C2, C3, and C4 had more evident physiological alterations (hypercapnia, acidosis) than those in C1 (p < 0.05). These signs indicate a process of transitory asphyxiation. The stillborn pups in all four categories had higher weights than their liveborn littermates. C3 and C4 had the highest mean weights (419.86 and 433.79 g, respectively) and mortality rates (C3 = 20.58%, C4 = 24.58%). Results suggest that if the weight of the bitch is >16.1 kg in eutocic births, there is a higher risk of intrapartum physiological alterations and death. The results of this study allowed us to identify that the weight of dams before birth determines the weight of the puppies at birth.

Thermal homeostasis in the newborn puppy: behavioral and physiological responses

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.

Thermal homeostasis in the newborn puppy: behavioral and physiological responses

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)

Maternal behaviour in domestic dogs.

Mammalian parental care, in most of the cases, is given by the female, who provides food, warmth, and protection. In domestic dogs, maternal behaviour shown by the dam mainly consists of contact, nursing, grooming/licking, play, punishment, thermoregulation, and motion. Peer-reviewed literature published between 1952 and 2018 was retrieved from CAB Abstracts, PubMed, ISI Web of Knowledge, Scopus and book chapters. Keywords for this search included the following terms: behaviour, bonding, altricial, precocial, offspring, maternal, whelping, nursing, domestic dogs, female dog, aggression, puppies, anogenital licking. In this review, we reported and discussed scientific information about maternal behaviour in domestic bitches, comparing altricial vs precocial species; the importance of the bonding, grooming/licking and nursing, and their impacts on puppies' behaviour; altered maternal behaviours such as aggression, cannibalism, rejection, and also the relation between hormones and maternal care behaviours. We concluded that the level of interactions between the dam and the puppies influences the physiological, cognitive and behavioural development of the litter, and the main hormones in the bitch for inducing maternal care behaviours are estradiol, oxytocin, prolactin and progesterone.