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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.
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International Journal of Veterinary Science and Medicine
ISSN: (Print) 2314-4599 (Online) Journal homepage:
Maternal behaviour in domestic dogs
Karina Lezama-García, Chiara Mariti, Daniel Mota-Rojas, Julio Martínez-
Burnes, Hugo Barrios-García & Angelo Gazzano
To cite this article: Karina Lezama-García, Chiara Mariti, Daniel Mota-Rojas, Julio Martínez-
Burnes, Hugo Barrios-García & Angelo Gazzano (2019) Maternal behaviour in domestic dogs,
International Journal of Veterinary Science and Medicine, 7:1, 20-30
To link to this article:
© 2019 The Author(s). Published by Informa
UK Limited, trading as Taylor & Francis
Published online: 21 Jul 2019.
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Maternal behaviour in domestic dogs
Karina Lezama-García
, Chiara Mariti
, Daniel Mota-Rojas
, Julio Martínez-Burnes
Hugo Barrios-García
and Angelo Gazzano
Neurophysiology, Behavior and Assessment of Welfare in Domestic Animals, Department of Animal Production and Agriculture,
Universidad Autónoma Metropolitana (UAM), Mexico City, Mexico;
Department of Veterinary Sciences, University of Pisa, Pisa, Italy;
Graduate and Research Department, Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma de Tamaulipas, Victoria,
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, ospring, mater-
nal, whelping, nursing, domestic dogs, female dog, aggression, puppies, anogenital licking. In
this review, we reported and discussed scientic 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 puppiesbehaviour; altered maternal
behaviours such as aggression, cannibalism, rejection, and also the relation between hor-
mones and maternal care behaviours. We concluded that the level of interactions between
the dam and the puppies inuences the physiological, cognitive and behavioural develop-
ment of the litter, and the main hormones in the bitch for inducing maternal care behaviours
are estradiol, oxytocin, prolactin and progesterone.
Received 7 February 2019
Revised 28 June 2019
Accepted 2 July 2019
Maternal care; dog
behaviour; whelping;
nursing; puppy welfare
1. Introduction
Mammalian parental care in dogs is mainly performed
by the dam, who provides food, warmth [1,2], shelter
and protection from predators and conspecics [3,4],
helping to the ospring´s survival and their mental and
physical well-being [5,6]. It has been documented that
maternal care has an impact on individualsdevelop-
ment in many species, including rodents, pigs, non-
human primates, humans and recently in adult dogs
[79]. The quantity of the relationship between the dam
and the ospring interpose on physiological, cognitive
and behavioural osprings development [10]. The
maternal behaviour detected on bitches towards the
litter includes contact, nursing, licking (mainly anogen-
ital licking, that allows newborn puppies to urinate and
defecate in a duly manner), play, punishment, thermo-
regulation and motion [11,12].
Maternal behaviour, delivery and nursing synchro-
nisation assure that the dam responds to osprings
needs in time. A variety of studies in newborn mam-
mals prove that maternal behaviour directly impacts
on the neonatal survival [1315] since mortality rates
between birth and weaning are related to maternal
and neonatal behaviour [1621].
Dogs are altricial animals and, for that reason, the
establishment of dam-ospring bonds can take days
or even weeks to develop. Nevertheless, nest building,
licking, nursing and puppys rearing is present in
most of the cases. In comparison with wild canine
species, domestic dogs are considered to have
a reduced disposition for maternal behaviour [22],
and therefore, human intervention is sometimes
required to increase puppiessurvival [12].
This review aims at discussing and comparing pro-
vided data by scientic papers about domestic dogs
maternal behaviour. Throughout this paper, we will
address several issues such as dierences in maternal
behaviour between both altricial and precocial species,
maternal skills, licking and dam-ospring bond signi-
cance and its impact on long-term puppiesbehaviour,
abnormal maternal behaviour, and the relationship
between maternal behaviour and bitcheshormonal
levels. In this way, current ndings allow readers to
get a comparison between the results of dierent
authorsstudies, and also to have a conclusion about
the last published data on bitch maternal behaviour.
2. Maternal behaviour in altricial vs precocial
Natal viability is associated with foetal maturity, envir-
onmental conditions, and maternal care [23]. Usually,
CONTACT Daniel Mota-Rojas Universidad Autónoma Metropolitana, Xochimilco. Calzada del Hueso 1100, Col. Villa
Quietud, Del. Coyoacán, Mexico City CP 04960, Mexico
2019, VOL. 7, NO. 1, 2030
© 2019 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (, which permits
unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
altricialand precocial terms areusedto indicate an early
for late stage of development at birth in mammals and
birds. The altricial-precocial scale describes the degree
of behavioural and morphological maturation of the
ospring at birth or hatching [24]. In precocial species,
ospring require minimal parental care and are rela-
tively mature, able to move and can feed themselves
(precocial birds) or forage independently from the start
while still being nursed (precocial mammals). In con-
trast, altricial canids, rodents, felids are initially incap-
able of moving around on their own and require
extensive parental care, like brooding or food access
[25]. In altricial species, such as the dog, ospring are
unable to care for themselves at birth, are usually born
deaf and blind, and have limited movement [12,26].
The ability of the newborn to survive and to grow
within the born environment depends on the vital
organsmaturation level at birth. Organs of placental
altricial neonates are capable of maintaining its vital
functions and the short-term metabolic changes
[27,28]. However, in some species, neonates need
a dam to hatch them or to feed them [25]. Altricial
species dams (as rodents, canines, and felines) built
a nest where they give birth to their ospring, which
are not fully developed and have limited sensorial and
motion skills [4,29]. Maternal behaviour largely diers
across species. For instance, once the rodent dam has
gathered its ospring within the nest, it spends most of
the time in a nursing position, grooming them and
eliminating faeces and urine [30]. In rabbits, maternal
behaviour is dierent: dam only suckles rabbits once or
twice a day, for periods no longer than 10 minutes each
[31]. Primate dams instead carry ospring most of the
time and hold it with its strong hands [32]. Dogs are born
blind and deaf, which limits newborn care [26]; for that
reason, puppiesphysical and social development is
mainly determined by the interaction with the dam
[33]. During the fth week postpartum, ospring fre-
quently gets out of the nest, and weaning starts [34].
In precocial species (most of the ungulates), o-
spring requires less parental care, as soon after birth
they can move and can graze between breast-feedings
[25]. Precocial placental newborns show an organs
advanced development state to keep vital functions,
thermoregulation, and a highly energetic perfor-
mance [27]. Immediately after birth, dam licks o-
spring until they are free of amniotic uid and
placental remains [35]. Precocial species deliver
small litters, with fully developed ospring, capable
of following the dam immediately after birth. Within
these species, dams develop discriminatory maternal
care that allows only its ospring to suck and avoid
other animals to do so [4,18].
The bitch nurses the puppies intensively during
the rst days, and hardly leaves the nest. If the pup-
pies roam around, the dam will lick them to return
them to the nest. From birth to three or four weeks
old, the dam needs to stimulate urination and defeca-
tion (through anogenital licking), and she will eat any
waste, feed the puppies, and provide a heat source to
maintain them at stable body temperature [36,37].
All the reviewed data agree that maternal beha-
viour shows meaningful dierences between precocial
and altricial species, which is less intense in precocial
species than in altricial ones. For a more comprehen-
sive review on altricial and precocial social complex-
ity, see Scheiber et al. [25].
3. Maternal behaviour and hormonal
In all mammal species, the period surrounding the
birth is characterised by an increase of plasma estra-
diol, prolactin, and cortisol levels, and by the activa-
tion of the oxytocinergic system at the time of
delivery [4].
The factors causing the onset of typical maternal
behaviours are still subject to debate and widely stu-
died in rodents [3841]. In rodents, the existence of
an attraction-acceptance neural circuit, that would
inhibit the activity of another defensive antisocial
neural circuit, has been hypothesised [38].
The hormonal constellation present at the end of
pregnancy allows a rapid display of maternal beha-
viour and acceptance of newborns, activating the
attraction-acceptance circuit [42].
Female primiparous rats immediately demonstrate
maternal behaviour, while virgin female rats when
exposed for the rst time to newborns, show avoid-
ance lasting for 34 days [43].
On one hand, in pregnant rats, the increase in the
blood concentration of oestrogens and prolactin
would activate the medial preoptic area (MPOA) of
the hypothalamus, making it capable of responding to
stimuli from newborns, inhibiting the antisocial
defensive circuit and activating the attraction-
acceptance circuit (the mesolimbic dopamine system,
MDS), resulting in prosocial maternal responses [44].
On the other hand, recent studies support the
hypothesis that, in rats, unfamiliar olfactory stimuli
from pups activate the neural circuit responsible for
pup avoidance in virgins, composed by the olfactory
bulb, medial amygdala, anterior hypothalamic
nucleus and periaqueductal gray [43].
According to Numan et al. [43], MPOA neurons,
primed by prolactin and estrogen, becomeresponsive to
pup stimuli and activate neurons of the ventral tegmen-
tal area of the midbrain, where MDS has its origin, and
release dopamine in the nucleus accumbens, located in
the subcortical cerebral hemispheres. Dopamine causes
a reduction in the response of the nucleus accumbens to
stimuli originating from the defensive antisocial neural
circuit. The nucleus accumbens would also be inhibited
in its regulatory activity of the ventral pallidum,
a motivational control region. The ventral pallidum
could, therefore, become active and allow the appear-
ance of maternal behaviour.
It is generally accepted that dams identify their o-
spring by olfaction and this seems related to oxytocin
release [9,18,20]. Oxytocin, a neuropeptide with the
dual action of hormone and neurotransmitter, is
another molecule largely involved in triggering mater-
nal behaviour. Oxytocin enhances maternal interest in
young dogs by reducing anxiety and stimulating mater-
nal care [42]. The posterior pituitary gland is the site of
oxytocin release after neurologic stimulation [45,46].
There are two recognised stimuli to induce oxytocin
release. The rst is Ferguson´s reex, that consists of the
pressure of the head of a puppy into the cervix during
parturition [45,47,48]: the cervicovaginal stimulation
during labour and the secretion of prolactin, along
with the presence of estradiol and progesterone, release
oxytocin by producing reactions in the maternal brain
[47](Figure 1). The second stimulus is the suckling
stimuli of the mammary glands by the puppies [45].
Oxytocin is produced by the neurons of the para-
ventricular nucleus of the hypothalamus, which projects
to many regions of the brain, including the MPOA. The
action of oxytocin would be that of potentiating the
stimulating activity of MPOA on MDS [44].
In rats, the long-term persistence of maternal beha-
viour, also known as maternal memory,is also
maintained by oxytocin and dopamine action in the
nucleus accumbens shell [49]. Oxytocin is also respon-
sible for the synchronised uterine contractions during
parturition and the further dilation of the cervix. In
contrast, progesterone maintains pregnancy by promot-
ing the secretion of intrauterine glands to sustenance the
fertilised eggs, stimulates the expansion of the mammary
glands, and induces maternal behaviour. Further, the
decrease of progesterone and a subsequent rise in pro-
lactin cause the common maternal behaviours seen in
dogs, including nesting [45,50](Figure 1).
After birth, puppies are exposed to particular
pheromones secreted by the sebaceous glands located
in mother intermammary sulcus, the area in between
her breast where puppies detect them upon nursing.
Because these pheromones provide calm, comfort
and a sense of well-being to the puppies, they are
called Dog Appeasing Pheromones (DAP) [46,51,52].
Another factor related to the duration of the eleva-
tion of some hormones is the parity number by which
the bitch is passing; that is, it can be dierent in primi-
parous and multiparous. In a study performed by Seki
et al. [53] the initial increase of progesterone levels was
of shorter duration in primiparous bitches [4].
According to the above, we can conclude that the
levels of oxytocin, prolactin, and progesterone are
closely related to maternal behaviour. Oxytocin med-
iates several forms of aliative behaviours, including
Figure 1. The behavioural repertoire of the bitch at birth. In order to trigger labour, there must be a decrease in the
progesterone, followed by the increase of the prostaglandin F
, which creates an increase in the oxytocin sensitivity in the
bitchs uterus. At this moment, the dog begins with the construction of the nest or to move away to some dark place. Likewise,
it increases the prolactin, and the release of oxytocin from the neurohypophysis, and with signs of fainting, vomiting,
inappetence, trembling, and uterine contractions start. Here it is when the dilation phase begins. Subsequently, the expulsion
phase and the Ferguson reex are activated, with more release of oxytocin; uterine contractions emerge, and the fetus places
itself, either anteriorly or posteriorly in the birth canal. The bitch starts to lick her vulva and to break the amnion, she cuts and
tears the umbilical cord, and subsequently, there is the placental expulsion, the bitch eats the placenta, and because of the
relaxin, prolactin, and oxytocin stimulus, the lactation starts.
parental care, and grooming [5456] the formation of
a pair-bond, as well as the establishment of the rela-
tionship between dams and ospring [57].
A study using potent prolactin inhibitors, mostly
dopamine agonists conrmed the role of prolactin as
luteotropic hormone from day 30 of pregnancy and
beyond and that it is crucial for the preparation,
initiation and sustaining lactation, as well as for the
activation of maternal and sexual behaviour [58].
Prolactin seems to be involved in ensuring maternal
behaviour, including the preparation for delivery and
the care of the litter, although it is not yet clear how it
shares these eects with oxytocin [59].
During the birthing process, the bitch licks the
placenta and start eating the foetal membranes, the
remains of the placenta and also tears the umbilical
cord [36,45,6062], reducing the contamination of
the nest and avoiding predators [36](Figure 2(a,b)).
Cleaning the newborn, and consuming the amniotic
uid and placenta, are common behaviours within
mammals [63], except the big aquatic mammals
(cetacean) or semi-aquatic (pinniped); likewise, the
dams produce vocalisations to keep close the o-
spring and drive away from the predators [4].
In most bitches and queens, a typical maternal
behaviour is that they wait until the whole litter is
born to feed them. It is generally accepted that dams
identify their ospring by olfaction, and this seems
related to oxytocin release [45,60].
The rst contact of puppies and kittens with the
mothers tit is by the sense of smell and by trials
and errors. The dam uses its paws to push the
newborns towards the nipples and allow them to
nurse. Also, the puppies and kittens press the
mammary gland to stimulate the descent of the
milk [45]. (Figure 3(a,b,c)).
After feeding the ospring, the dam stimulates in
them urination and defecation through anogenital
Figure 2. (a) The bitch breaks the amnion and devours the
fetal membranes, initially from the puppys head so it can
breathe quickly, and then cleans the rest of the body, licking
it and in the same way stimulating the ospring (Photo MVZ
David Rivera). (b) The bitch tears the umbilical cord keeps
licking and cleaning the puppy, and when the dam throws
the placenta, she starts eating it to avoid the nest contam-
ination and thus not attract predators. Placentophagy favours
the uterine involution and milk production.
Figure 3. Maternal behaviour at parturition. (a) The bitch,
provides warmth and protection to the puppy and stays with
it most of the time. It only leaves the nest to feed, urinate
and defecate. The rest of the time it is taking care of the
ospring at least during the rst three weeks of the puppys
life. (b) The bitch pushes out the puppy with the snout to
mammary glands to facilitate its nursing. By doing so, it takes
advantage of licking the osprings genitals to stimulate the
puppy to urinate and defecate. In this picture, we can
observe the osprings umbilical cord, which will detach
approximately on the third day of birth. (c) Since the puppy
fails to move around by itself, bitch helps it by gently grab-
bing the neck with the muzzle to move it from place to place.
Those mentioned above continue when the puppies
and kittens start moving and until three weeks of age.
During the rst week after parturition, the dam
rarely leaves alone the ospring, only to eat, urinate
and defecate. Maternal care can dier depending on
the experience of the mother: maternal care (specically
licking the anogenital area, lactation and staying in
contact with the puppies) during the rst three weeks
is markedly higher in primiparous than in multiparous
mothers [64]. Later (the 4
week after delivery) the dam
becomes evasive, rejecting the ospring to suckle as
their teeth start to erupt, and leave the litter for
extended periods [45,60]. In primiparous dams,
a higher licking of the anogenital area, nursing and
contact with the puppies from day 1 to 21 was found,
which led to a more signicant amount of maternal care
in the third week compared to multiparous mothers.
3.1. Milk production from the hormonal point of
The study of the biological mechanisms that inuence
on regulates pregnancy, delivery, and lactation, is very
important to understand maternal responses. Maternal
behaviours usually arise immediately after birth, where
the female quickly shows great interest in the newborn.
However, the most essential and natural maternal beha-
viour in mammals is lactation (Figure 5(a,b)), which
occurs right after birth and ensures that newborns grow
up healthy and strong [4].
The hormones prolactin and oxytocin play an essen-
tial role during lactation. Prolactin promotes milk pro-
duction and incites normal maternal behaviour.
Prolactin release is stimulated during pregnancy, and
its blood levels rise suddenly at parturition, while other
hormone concentrations abruptly decrease [45].
Oxytocin stimulates descent of milk into the mammary
glands, and its blood levels are high during nursing.
A correlation between the quantity of oxytocin secreted
with the eciency of milk production is described in
some species [50].
4. Ospring grooming
Maternal licking in rats is associated with changes in
ospring behaviour, such as maternal and anxiety-like
behaviour [65]. It also aects receptors of glucocorti-
coid [66], oxytocin, vasopressin [67] and estrogen [68].
Published studies in animal models remark the
relevance of the extent of nursing, anogenital and
body licking, and the close body contact of the dam
with the ospring. These behaviours may further
inuence the emotionally [69] and stress response
and social skills of the neonates [68,70,71].
Moreover, Champagne et al. [68]describethatindi-
vidual pups within a litter receive the same amount
of licking and grooming.
For all the above, it is unquestionable that licking
is one of the leading maternal behaviours that may
further aect the puppiesbehaviours and the inter-
actions in their environments.
5. Bonding between dam-ospring and
maternal care
For parents, recognising their ospring help to prevent
misdirected parental care, limits energy losses, and
ensures reproductive success. On the other hand: for
young animals, recognition of parents is also essential
to their survival, since, in most species, parents feed only
their newborns. There is evidence that parent-ospring
recognition is crucial for colonial species, though the
degree of recognition seems to vary among dierent
species depending to some degree on environmental
constraints [4,72]. For the ospringofallmammalspe-
cies, their mothers are the essential social contact during
the rst months of life as they facilitate acquiring infor-
mation about physical and social environments [73].
Besides providing genetic material, parents also play
afundamentalroleintheospring development [33].
The quality and quantity of the relationships between the
dam and the ospring take part in the puppiesphysio-
logical, cognitive and behavioural development
during the early stages plays an essential role in their
development, just as the following character and beha-
viour. For example, maternal behaviour alters the
hypothalamic-pituitary-adrenal axis or stress responsive-
ness pathways of the neonate, and these changes persist
throughout adult life [12]. In two studies conducted by
Guardini et al. [10,75], it has been found an association
between the amount of maternal care provided by the
mother to each puppy and their behaviour at two months
of age, suggesting that the extent of maternal care that
puppies receive during the neonatal period inuences
their coping strategies at two months of age. However,
the patterns of behavioural responses widely diered
according to the environment in which puppies were
raised, so that authors suggested that maternal care con-
tributes to the adaptation of puppies to their environ-
ment, especially to the social relationship with humans
[75]. Besides, a high level of maternal care in dogs inu-
ences physical and social engagement, aggression, and
lower levels of anxiety and fear [8,10,76].
In the same way, in a study accomplished by Foyer
et al. [8], they taped 22 German shepherd litters during
the rst three weeks postpartum, to evaluate maternal
care variations and their eects on behaviour and tem-
perament in puppies around one and a half years of age.
They observed that the maternal care level varied
between dierent bitches, during the rst three weeks
after birth, and this aected the social and physical
engagements, as well as aggression, in the ospring
when they became adults. Foyer at al [8]. also found
that the amount and quality of maternal care would vary
during the suckling period and that better maternal care
would lead to less reactive, more condent and explora-
tive puppies.
The maternal care and the early postnatal environ-
ment may also have marked eects on subsequent
stress-related behaviours. Tiira and Lohi [76]described
the correlation between maternal care in puppies and
the later development of anxiety. They collected data
from a family dog population (n = 3264) to evaluate the
association between environmental factors and fearful-
ness, noise sensitivity, and separation anxiety. The study
revealed that fearful dogs had had signicantly fewer
socialisation experiences and lower quality of maternal
care during puppyhood. Noise sensitivity and separa-
tion anxiety was associated with a lower level of daily
exercise. Authors suggest that dogs share many of the
same environmental factors that contribute to anxiety
in other species, such as humans and rodents.
Nonetheless, there are limited studies about mater-
nal care as a predisposing factor for anxiety, because it is
a relatively new concept in dogs, but described in other
altricial species [12]. Also, the environment may aect
puppiesbehaviours once they are adults. A study con-
ducted by Appleby et al. [77], described higher aggres-
sion rangesin adult dogs when they were puppies raised
in non-domestic maternal environments, compared to
those raised in domestic maternal conditions.
A study conducted by Bray et al. [78], follow 98
puppies from birth to adulthood, who were allocated
to be guide dogs and they observed a link between high
levels of maternal behaviour and a higher probability
of program failure. Also, that the dams who require
a higher eort from puppies to accomplish nursing are
more likely to have successful ospring to be guide
dogs; on the other hand, dams whose lactation
requires less eort from puppies are more likely to
have ospring who will not perform as guide dogs.
The same study describes in the temperament tests
that there is an association between maternal beha-
viours and the young adult behaviour, on the same
way that Foyer et al. [8] and Guardini et al. [10].
However, unlike them, Bray et al. [78] found that the
extreme maternal care is directly linked to adverse
anxiety behaviours in dogs when they are young
adults, as well as poor problem resolution and the
decrease of latency at the rst barking period.
Another study conducted by Bray et al. [79], mon-
itored maternal interactions in twenty-one litters
from three dierent breeds. The study revealed that
a mothers attitude and actions toward her ospring
varied naturally between individuals and that these
variations could be summarised by a single principal
component, which they described as Maternal
Behaviour. This element was stable across weeks,
associated with the breed, litter size, and parity, but
not redundant with these attributes.
6. Abnormal maternal behaviours;
aggression, cannibalism, reject, pseudocyesis
Studies have identied dierent causes for abnormal
maternal behaviour, such as high prepartum and
postpartum stress levels [8083], hereditary predis-
position [84], low serotonin levels [85], and low oxy-
tocin levels [86].
6.1. Aggression
Maternal aggression is usually temporal, and it will
decrease just as puppies grow up [87]. The aggression
is towards whoever approaches the nest, to the pup-
pies or the objects the bitch perceives as puppies
during the false gestation [88].
In bitches, aggression may exacerbate by vocalisa-
tion of puppies. However, the aggressiveness may be
associated with pain, for example, in cases of mastitis
[45]. There is a critical role for oxytocin in the onset
between the dam and ospring bonding, associated
with low stress and fear [89,90], and on the increasing
maternal aggression toward threats [91].
The bitches with maternal aggressiveness monitor
the nest, the puppies, or when a person or an animal
is near. The puppies represent a precious resource for
the bitch, in which it has already invested much energy
required for a satisfactory pregnancy. The hormonal
changes associated with lactation can alter the dam
evaluation or perception of the range of resources, and
involve protection even in ordinary objects, with an
apparent disproportional ferocity. Fears may follow
attacks or bites in some cases [88]. The lactating bitches
may become aggressive towards humans or even
canines. This behaviour may cause diculties when
trying to control the puppies progress and to secure
adequate socialisation. The aggression may be acceler-
ated because of environment troubles, especially in
anxious or immature bitches, within an unstable social
environment [36], and it decreases after a few days or
weeks, when the puppies grow up and become less
dependent on the dam and, therefore, their defence
needs are reduced [88].
6.2. Cannibalism
Maternal cannibalism is also called cronyism [45], and
it is a condition where a dam consumes her ospring
after killing them [92,93]. It is abnormal maternal beha-
viour unless it is a strategy to reduce litter size, balance
the sex ratio of the ospring, eliminate the ospring that
has come out defective [80,94]orwhenthereisapoor
signicant environmental condition [95]. The dam can
accidentally kill and devour a puppy during the process
of cutting the umbilical cord (Figure 4)[36]. Although
some biological factors, such as low levels of oxytocin
and blood lipids are related to a failure in maternal
behaviour in dierent animals, this had not been inves-
tigated in detail. Kockaya et al. [93] measured these
substances in the serum of 15 adult Kangal bitches,
who had a cannibalism background, compared with
15 samples of bitches from the same breed, who had
no maternal cannibalism background. The results
revealed signicantly lower levels of these substances
in bitches with a maternal aggressiveness background.
The oxytocin levels of 3.58 + 0.43 ng/ml and cholesterol
at 125.50 + 8.6 mg/dL in dogs with cannibalism, com-
pared with oxytocin of 9.68 + 1.58 ng/ml and choles-
terol at 159.18 + 13.85 mg/dL in bitches with normal
postpartum behaviour. Thus, they concluded that oxy-
tocin is an essential neuroendocrine factor in bitches, to
develop normal maternal behaviour.
Bitches rarely direct severe aggression towards
their puppies and are more likely to manifest such
behaviours with their rst litter. However, there are
some cases in which bitches have caused severe inju-
ries and are considered a hereditary trait [96]. Causes
of cannibalism include pain (usually associated with
mastitis) and eclampsia, a large litter, stress, and
overcrowding [45].
6.3. Rejection of the ospring
Rejection of the ospring or maternal negligence, it is
uncommon, but some bitches may fail to attend their
puppies regarding warm, nutrition and urine and
faeces elimination [97]. Primiparous dams are more
prone to rejection. Also, in anxious dams who leave
the nest frequently, those with premature litters (less
than 57 days of gestation), litters born through a cae-
sarean section or where there are many discomforts
in the environment [36]. Breeding practices can also
alter the behaviour of the bitch towards her litter,
such as removing the pups from the nest areas and
holding them for a short period [98].
Rejection behaviour of the ospring is described in
bitches under some conditions, including when one
or two puppies are repeatedly moved from the nest or
hidden, then the dam perceives that something is
wrong with that puppy. Also, bitches routinely reject
pups that are cold or are not moving. However, if the
entire litter is rejected, it suggests that something is
wrong with the dam and medical assistance is neces-
sary to identify clinical signs of morbidities as masti-
tis, metritis, and eclampsia, or stressing factors
(overcrowding, large litters). Some primiparous
bitches are poor mothers, especially if they are ner-
vous or anxious. However, many of these dams tend
to be good mothers with subsequent litters [45].
6.4. Pseudocyesis
Pseudocyesis (also called false pregnancy) is a common
condition where the non-pregnant bitch goes through
Figure 4. Sometimes due to inexperience (primiparous) or
nervousness, the bitch pulls too much the umbilical cord of
the newborn when trying to tear it and this may cause
injuries in the puppy (such as evisceration) or inclusive can-
nibalism (Photo MVZ Gibran Olivera Rodríguez).
Figure 5. (a) The bitch acquires a lateral decubitus position to
nurse the ospring; they look for the closest nipple and begin
to suck hard. (Photo MVZ Esp. Juan Jose Santiago Garcia). (b)
The puppy indistinctly selects a nipple and begins to suck
and make massage movements that stimulate the mammary
gland to release milk (Photo MVZ Esp. Juan José Santiago
the same hormonal changes as the pregnant one. It can
depend on both serum prolactin levels and the sensitivity
of tissues to this hormone [36]. Pseudocyesis can be
underdiagnosed in bitches and may be the cause of
some cases of behavioural problems, including aggres-
sion [99]. At the end of dioestrus, when progesterone
concentrations fall, and prolactin concentrations rise, the
female dog exhibits mammary development, produces
milk and may show behavioural changes as if she is
whelped such as nesting and mothering of inanimate
objects and some bitches may become aggressive [45].
Apart from typical maternal behaviours such as care,
grooming, vomiting, the dam may show the enlargement
of the mammary glands, as well as restlessness and con-
struction behaviour nest, similar to the pregnant bitches
that have delivered before,anxiety,agitation,lethargy,
aggression and pain [36,88,99101]. Roth et al. [99]
developed a survey applied to 2000 veterinarians, to
know the frequency of cases of pseudocyesis in dogs
and the signs observed. The results revealed that 96% of
the respondents reported having observed cases of pseu-
docyesis with changes in maternal behavioural (the most
common was that the bitches adopted objects as if they
were puppies). Pseudocyesis was reported in 49% in
sterilised bitches, and the most common physical sign
was the enlargement of the mammary gland and milk
production (89%). Besides, 97% of veterinarians reported
cases of aggression associated with pseudocyesis.
7. Conclusion
Dogs are altricial species that depend entirely on the
dam to survive, obtaining warm, food, movement, pro-
tection from predators and stimulation through ano-
genital licking to eliminate waste. The main dierence
in maternal behaviour between altricial and precocial
species is that, in the rst, the dam-breeding link takes
from one day until weeks to be established, while in the
precocial, this bond is generated even in hours. For
delivery and maternal behaviour to take place, a set of
factors must happen both in the foetus and in the bitch,
thus activating the series of hormones involved, such as
oestradiol, cortisol, progesterone, prolactin, oxytocin,
and relaxin. The normal maternal behaviours include
the creation of the nest, contact, nursing, licking, play,
punishment and within abnormal maternal behaviours
authors describe aggression, pseudocyesis, cannibalism,
and abandonment of the ospring. Abnormal maternal
behaviour in the bitch is related to low levels of some
hormones, mainly oxytocin. All the authors revised
agree on the relationship between maternal care of
breeding and the development of desirable or undesir-
able behaviours in puppies when they are adults. With
more maternal care, the puppy becomes more depen-
dent, anxious and has a harder time adapting to its
environment. However, to date, few studies describe
maternal behaviour in domestic dogs, so it is necessary
to continue researching this topic.
Disclosure statement
No potential conict of interest was reported by the
Karina Lezama-García
Chiara Mariti
Daniel Mota-Rojas
Julio Martínez-Burnes
Hugo Barrios-García
Angelo Gazzano
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... When the intruder is a stranger, the attack is brutal and direct. Maternal aggression resembles territorial and distancing aggression, because the female dog in most cases, fiercely defends not only the puppies but also the place where she gave birth or the place where the puppies usually live [18] ...
... As a predator, the dog reacts to moving objects or creatures by chasing, which is a natural behavior for him. As in the case of hunting aggression, there are breeds whose tendencies to chase are conditioned by genes and its utility [18] ...
... This also applies to small breeds of dogs when the aggressor is a representative of a large breed of dog. The occurrence of hunting aggression is largely determined by the genes and utility of the breed [18] ...
Full-text available
Aggression as a behavior is not always desirable, often ends in abandonment and/or euthanasia. However, it is possible to prevent the occurrence of unwanted aggression in domestic dogs. Aggression is not a fully understood phenomenon. In recent years, many studies have focused on the influence of diet and physiology (including the endocrine system) on the emergence of behavioral disorders. In particular, the emphasis was put on nutritional additives such as fatty acids, amino acids, and probiotics. In addition, the possibility of using neurocognition in the observation of abnormal behavior in dogs has also been discussed, which may allow for a more detailed determination of the basis of aggressive behavior in dogs. In this review, the concepts related to aggression and its potential causes have been gathered. In addition, the possible influence of diet and hormones on aggression in dogs has been discussed, as well as the application of neurocognition in the possibility of its diagnosis
... More specifically, we applied this method to investigate how the presence and duration of NLP in distress whines, produced by 1-to 9-week-old domestic dog puppies, affect their perception by humans. Whines are high-pitched tonal calls considered to signal distress, typically given by puppies during separation [33] or aggression by their mother [34]. Like adult dog whines [11,12], puppy whines also often contain NLP (see electronic supplementary material). ...
... Like adult dog whines [11,12], puppy whines also often contain NLP (see electronic supplementary material). Although puppies' survival mainly relies on mothers, who intensively breastfeed, groom and warm them [34], the intervention of human caregivers is sometimes required for breeding in this domesticated species [35]. As such, NLP in whines may be important to attract the attention of the mother, but also of humans, ensuring that puppies receive care. ...
... It was thus unlikely that we induced stressful behaviours in mothers while recording their puppies. In addition, when bringing the puppy back to its mother, the observation of normal maternal behaviours such as grooming or breastfeeding [34] indicated low stress levels. ...
While nonlinear phenomena (NLP) are widely reported in animal vocalizations, often causing perceptual harshness and roughness, their communicative function remains debated. Several hypotheses have been put forward: attention-grabbing, communication of distress, exaggeration of body size and dominance. Here, we use state-of-the-art sound synthesis to investigate how NLP affect the perception of puppy whines by human listeners. Listeners assessed the distress, size or dominance conveyed by synthetic puppy whines with manipulated NLP, including frequency jumps and varying proportions of subharmonics, sidebands and deterministic chaos. We found that the presence of chaos increased the puppy's perceived level of distress and that this effect held across a range of representative fundamental frequency (fo) levels. Adding sidebands and subharmonics also increased perceived distress among listeners who have extensive caregiving experience with pre-weaned puppies (e.g. breeders, veterinarians). Finally, we found that whines with added chaos, subharmonics or sidebands were associated with larger and more dominant puppies, although these biases were attenuated in experienced caregivers. Together, our results show that nonlinear phenomena in puppy whines can convey rich information to human listeners and therefore may be crucial for offspring survival during breeding of a domesticated species.
... However, it is considered that the morphological variability in dogs could affect fetal development [2,[13][14][15]. For newborn puppies, the presence of other factors, such as maternal care [16,17], uterine inertia [18,19], and prolonged labor predisposes them to hypoxia and Type II stillborn (SB) [20][21][22][23]. Type II stillborn (SB) is considered to be an effect that is associated with the oxytocinergic system of the dam and its regulation. ...
... In dogs, the concentration of oxytocin and the expression of oxytocin receptors are key elements for the onset of parturition. Since this hormone maintains the synchronized uterine contractions and dilatation of the cervix to facilitate a eutocic parturition [17], abnormalities in the oxytocinergic system could extend the time of parturition and, therefore, the consequences of delayed birth. For example, Cornelius et al. [53] determined that canine pups with dystocia were 2.35 times more likely to be stillborn due to one of the leading causes of delayed parturition: uterine inertia. ...
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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.
... However, it is considered that the morphological variability in dogs could affect fetal development [2,[13][14][15]. For newborn puppies, the presence of other factors, such as maternal care [16,17], uterine inertia [18,19], and prolonged labor predisposes them to hypoxia and Type II stillborn (SB) [20][21][22][23]. Type II stillborn (SB) is considered to be an effect that is associated with the oxytocinergic system of the dam and its regulation. ...
... In dogs, the concentration of oxytocin and the expression of oxytocin receptors are key elements for the onset of parturition. Since this hormone maintains the synchronized uterine contractions and dilatation of the cervix to facilitate a eutocic parturition [17], abnormalities in the oxytocinergic system could extend the time of parturition and, therefore, the consequences of delayed birth. For example, Cornelius et al. [53]determined that canine pups with dystocia were 2.35 times more likely to be stillborn due to one of the leading causes of delayed parturition: uterine inertia. ...
... A high neurologic morbidity increases the risk of neonatal mortality [14]. The birthing process is the most critical phase for newborns [15] because the transition from fetus to neonate involves physiological, biochemical, and anatomical changes accompanied by flows of hormones that trigger the respiratory function, vascular changes, and the activation of energy metabolism [16,17]; additionally, the maternal behavior is critical for the parturition to take place in favorable conditions for the newborn puppy [18][19][20][21]. Studies of dogs have reported that a certain level of transitory asphyxiation occurs during delivery. ...
... It is believed that the fetus' capacity to withstand birth stress and welfare depends on both its condition at birth and the birthing process itself (duration, number of contractions, fetus thermoregulation, physiological, and metabolic changes. In addition, the newborn has to make several adjustments to adapt to extrauterine life, such as maintaining normoglycemia, thermoregulation, etc.) [18,[90][91][92][93][94][95]. ...
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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.
... In dogs, as with all mammalian species, the mothernewborn bond is crucial for the suitable development of maternal behavior that guarantees offspring survival. In dogs, both natural birth and assisted delivery might be a stressful and painful experience, which could affect the way a bitch cares for her litter [99]. A female in pain may present a weaker maternal instinct and refuse to care for or feed her puppies. ...
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The perinatal period has a critical impact on viability of the newborns. The variety of factors that can potentially affect the health of a litter during pregnancy, birth, and the first weeks of life requires proper attention from both the breeder and the veterinarian. The health status of puppies can be influenced by various maternal factors, including breed characteristics, anatomy, quality of nutrition, delivery assistance, neonatal care, and environmental or infectious agents encountered during pregnancy. Regular examinations and pregnancy monitoring are key tools for early detection of signals that can indicate disorders even before clinical signs occur. Early detection significantly increases the chances of puppies’ survival and proper development. The purpose of the review was to summarize and discuss the complex interactions between all elements that, throughout pregnancy and the first days of life, have a tangible impact on the subsequent fate of the offspring. Many of these components continue to pose challenges in veterinary neonatology; thus, publications presenting the current state of knowledge in this field are in demand.
Providing behavioral care to animals in special circumstances, such as following a natural disaster or after removal from a cruelty or neglect situation, presents a variety of unique challenges. Following disasters, animals are often held in rudimentary field shelters until they are reunited with their owners or considered unclaimed. Cruelty cases involve populations of animals, such as dogs from organized dogfighting operations and animals from hoarding situations, that present with behavioral needs for safe and humane sheltering. Long‐term holds, often due to legal cases, compound shelter stress over time, which can lead to behavioral decline. These special circumstances represent substantial challenges to maintaining animal welfare. Even when faced with less‐than‐ideal conditions and other limitations, best efforts should be made to prevent, mitigate, or eliminate negative welfare and to facilitate psychological well‐being.
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Military dogs, besides being exposed to stressful events during operations (loud noises, transport, exposure to high and low temperatures, etc.), can be involved in explosions and/or gunshot wounds. Breeding, selection and management of working dogs are specific activities that involve a deep knowledge of different disciplines such as genetics, animal husbandry, internal medicine and applied ethology. This study aimed to provide specific guidelines on the breeding and behavioral management of German Shepherd and Belgian Malinois military dogs, from birth to the seventh month of age. The deep knowledge of the dog from the point of view of applied ethology and the psychology of learning, beyond a natural predisposition to interact correctly with the dog, are the most important topics for a good canine trainer; education and dog training are only a direct and natural consequence of this.
Pain treatment of lactating bitches is a clinically relevant, but complicated issue. Published scientific studies regarding the excretion of drugs in canine milk are scarce. When considering the risk of side effects in their offspring, lactating bitches have traditionally received very restricted analgesic and anti-inflammatory therapy. Our aim was to quantify the concentrations of carprofen in milk from lactating bitches and relate those to potential risks for the puppies. A second aim was to evaluate the impact mastitis may have on the concentration of carprofen in milk. A population of 100 bitches was enrolled in the study, among which 88 were bitches treated with carprofen after cesarean section (Group CS), eight were bitches with painful inflammatory conditions (Group I) and four were bitches with mastitis (Group M). The patients enrolled in the study received carprofen 4 mg/kg sc at day 1 followed by 2 mg/kg po every 12 h for the following 2–5 days. Owners were instructed to collect milk once a day for five days. The concentration of carprofen in the milk was quantified with ultra-performance liquid chromatography-tandem mass spectrometry. The data obtained were statistically analyzed as repeated-measures data with a mixed-model approach. Data were used to calculate the theoretical maximum total daily intake of carprofen by the puppies in order to perform a computerized simulation of the plasma concentration of carprofen in the puppies. Follow-up telephone interviews to check the status of the enrolled bitches and their litters occurred at one week and three-six months after treatment with carprofen. The major finding of the study was that the concentration of carprofen in the milk was <700 ng/mL from bitches undergoing CS or suffering painful conditions other than mastitis. In comparison, administration of 2 mg/kg of carprofen sc or po to adult dogs, results in mean maximal plasma concentrations of 19480 ± 5420 ng/mL (mean ± SD). Moreover, data suggests that inflammation of the mammary gland results in a higher concentration of carprofen in milk (up to 1300 ng/mL). In the computerized simulation, the plasma concentrations of carprofen in puppies in group CS and in group I are one tenth of the concentration in adult dogs receiving carprofen at standard doses. Considering the low excretion into milk, carprofen provides an analgesic alternative to lactating bitches without mastitis.
Full-text available Parturition is a complex physiological process and involves many hormonal, morphological, physiological, and behavioural changes. Labour is a crucial moment for numerous species and is usually the most painful experience in females. Contrary to the extensive research in humans, there are limited pain studies associated with the birth process in domestic animals. Nonetheless, awareness of parturition has increased among the public, owners, and the scientific community during recent years. Dystocia is a significant factor that increases the level of parturition pain. It is considered less common in polytocous species because newborns’ number and small size might lead to the belief that the parturition process is less painful than in monotocous animal species and humans. This review aims to provide elements of the current knowledge about human labour pain (monotocous species), the relevant contribution of the rat model to human labour pain, and the current clinical and experimental knowledge of parturition pain mechanisms in domestic animals that support the fact that domestic polytocous species also experience pain. Moreover, both for women and domestic animal species, parturition’s pain represents a potential welfare concern, and information on pain indicators and the appropriate analgesic therapy are discussed.
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Meconium aspiration syndrome (MAS) is a common obstetric and paediatric problem and is one of the most common causes of neonatal respiratory distress. The pathophysiology of MAS is complex. The underlying mechanism of MAS is fetal hypoxia which causes redistribution of fetal blood, increased intestinal peristalsis and relaxation of the anal sphincter in utero , leading to the passage of meconium into the amniotic fluid. If hypoxia is severe and persistent, the fetus gasps for air, but instead aspirate amniotic fluid contaminated with meconium. Aspiration of meconium produces multiple physiological and structural changes in the neonatal lung which relates partially to the amount of aspirated meconium. The structural and functional sequels of MAS include airways obstruction, atelectasis, chemical pneumonitis, hypoxemia, acidosis, pulmonary hypertension and occasionally death. MAS survivors can develop airway hyperreactivity and nervous sequelae. The morbidity and mortality of human MAS have declined the last decades because of new therapies but remains a major paediatric problem. Although the prevalence and significance of MAS in veterinary medicine have been poorly investigated, there is ample evidence that intrapartum hypoxia in animals also causes meconium expulsion, amniotic staining and aspiration. The lungs of affected animals showed airway obstruction, focal atelectasis and alveolitis. Meconium staining of the skin and aspiration are indicators of fetal or perinatal hypoxia and postnatal respiratory distress in domestic animals. Experimental models have been developed to study the pathogenesis of MAS in laboratory animals. This review focuses on the current concepts of the pathophysiology of MAS in human and veterinary medicine.
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Olfaction is the primary sensory communication mode for most mammals; social, sexual, maternal and feeding behaviours are four basic and fundamental aspects directly related to olfaction. Herein we consider these four main aspects of olfaction in a variety of mammals from the families Ungulata and Carnivora. Firstly, we provide a brief explanation on the anatomy and how olfaction is modulated. In particular, we discuss the literature in the context of recent trends in main olfactory epithelium and vomeronasal organ functions, briefly explaining the main differences between the anatomical olfactory structures of various domestic animals. Subsequently, examples of animal welfare implications of diet selection, predation, aversion, breeding and mother–young bonding behaviours are described. An ethological view of olfaction in addition to the brain structure and olfaction morphology aspects has been covered, as it offers a promising approach in the welfare of mammalian species under our care. We conclude that the knowledge of the roles played by olfaction in chemical communication may help improving housing conditions, fulfilment of feeding requirements, handling and breeding of companion, farm and zoo mammals, and promote the development of appropriate social, sexual, parental and feeding behaviours thus enhancing animal welfare.
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There is a high demand for a veterinary education in animal welfare (AW) with different approaches from the academic, society and trade points of view. Latin American (LA) countries members of the World Organization for Animal Health (OIE) are under the urge and should be obligated to teach AW. The aims of this article are to analyze the current drives of change on the importance of teaching animal welfare in LA, the competences recommended from international education organizations for the region, and to provide the contents on the curriculum in AW that a future veterinarian should achieve in the LA scenario, in other words to examine why teaching AW, what should be taught and how. Despite significant advances in introducing AW into veterinary training programs, much remains to be done regarding the future of this field in teaching veterinary science in Spain and LA countries, and in including this science as an independent course in programs at distinct levels to integrate the scientific, ethical and legal aspects of AW. This paper presents a proposal that was constructed with a view towards integrating diverse curricular approaches based on criteria, contents and concepts provided by the researchers and professors who collaborated in the book entitled: Bienestar Animal: Una Visión Global en Iberoamerica [Animal Welfare: A Global Vision in Ibero-America]. To ensure veterinary students will be better equipped to graduate with OIE day 1 competencies in AW, teaching approaches are needed that support project-based learning and gamification, critical thinking, reflection and collaborative learning. Keywords: Animal welfare, Study plans, Study programs, Teaching, Veterinary medicine
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Background There is a dearth of literature on pseudopregnancy in the bitch, with only a few treatment-based studies published since the 1990s. Pseudopregnancy may be under-recognised in bitches and may account for a proportion of behavioural cases seen in veterinary practices including aggression. Little is known about commonly used treatments for overtly pseudopregnant bitches and it is possible that current regimes may not be prescribed for a sufficient duration to control any clinical signs including, physical and behavioural changes. To investigate current trends in diagnosis and treatment of canine pseudopregnancy, a postal survey was sent to 2000 randomly selected veterinary surgeons in UK veterinary practices. The questionnaire queried how often vets recognise cases of pseudopregnancy in spayed and entire bitches, which physical or behavioural signs are commonly recognised for diagnosis, and which management or treatment protocols are used. Results The response rate was 19.8% (397/2000). Ninety-six percent of veterinary surgeons reported seeing pseudopregnant bitches showing behavioural changes without any physical changes within the last 12 months. Of those behavioural changes, collecting and mothering objects was the most frequently reported behavioural sign (96%). Ninety-seven percent of vets had seen aggression in pseudopregnant bitches. Nevertheless, only 52% of vets routinely asked owners about behavioural changes during consultations. Forty-nine percent of respondents reported seeing pseudopregnancy in spayed bitches. The most commonly reported physical sign was enlarged mammary glands and/or milk production (89%). Treatment options varied (surgical, medical or none) and depended on duration and severity of physical and behavioural signs, owners’ preference, cost, concurrent disease, drug availability and previous history. Conclusions This is the largest epidemiological study of canine pseudopregnancy in the UK. The prevalence and severity of clinical signs in dogs with pseudopregnancy are variable and possibly under-estimated. Dogs with overt pseudopregnancy experience diverse physical and behavioural changes and information on standard treatment protocols are lacking. Although, progress on our understanding of diagnosis and treatment of pseudopregnancy in spayed and entire bitches has been made, further studies are warranted.
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Dystocia can be defined broadly as “difficult birth” or more specifically as difficulty in the bitch expelling the pups through the cervix, vagina, and vestibule. It is a fairly common emergency presented to the small animal practitioner with an incidence rate of approximately 5%. The incidence of dystocia is highest in toy and brachycephalic breeds, and occurs frequently in small litters (< 3 pups) due to fetal oversize and delayed onset of labor. As duration of labor progresses, the mortality of the pups and even the bitch increases, with the highest number of stillborn pups occurring after six hours from the time of active parturition. Practitioners should understand the mechanism of normal parturition so that abnormalities can be readily identified and medical or surgical intervention performed in a safe and timely manner.
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Maternal care has been shown to affect the development of the brain, behaviour, social skills and emotional systems of the young of many mammalian species including dogs. The aim of the present study was to determine the effects of maternal care on the behavioural responses of family dog puppies towards environmental and social stimuli. In order to do this, maternal care (licking puppy's ano-genital area, licking the puppy, nursing and mother-puppy contact) during the first three weeks after birth was assessed in 12 litters of domestic dog puppies reared in home environments (total = 72 puppies). The behavioural responses of puppies were assessed in an arena and an isolation test, which were performed when the puppies were two-month old. Data were analysed using principal components analysis and projection to latent structures regression. A systematic relationship was found between maternal care and behaviour in both tests. In the arena test, maternal care was found to be positively associated with approach to the stranger, attention oriented to the stranger, time spent near the enclosure, yawning, whining and yelping (R²Y = 0.613, p = 8.2 × 10-9). Amount of maternal care was negatively associated with the number of squares crossed and the time spent individually playing with the rope. In the isolation test, the amount of maternal care was positively associated with standing posture, paw lifting, and howling, and it was negatively associated with yawning, lying down and nose licking (R²Y = 0.507, p = 0.000626). These results suggest that the amount of maternal care received during early life influences the pattern of behavioural responses and coping strategies of puppies at two-months of age. On the basis of these findings it could be speculated that early maternal care contributes to adaption to the environment in which family puppies are developing, with particular regard to social relationships with people.
In many animal species, facial expressions are key elements for recognising emotions and numerous types of social interaction. Emotions are complex reactions that allow individuals to cope with full events that have either positive or negative meaning and involve certain neurophysiological responses proper to each emotion and species. Regulating emotional states requires integrating a whole series of responses –peripheral, autonomous, endocrine and muscular– that entail activating various sub-cortical structures, including the amygdale, hypothalamus and brainstem. In recent decades, interest in the emotions expressed by animals has grown, and researchers have come to understand that some problems of animal welfare can be detected by examining and comprehending the emotional experiences that animals may suffer, and identifying how they demonstrate their reactions through facial expressions and corporal postures. The objective of this review is to examine recent literature on aspects related to the function of the emotions and facial expressions in certain domestic species:–cats, dogs, rats, sheep, horses and pigs– and propose that understanding facial expressions can be useful as a complement to existing tools in assessing welfare and working with, or doing research on, these species.
Labour challenges the newborn to adapt to extrauterine life and survive the troublesome neonatal period. Low vitality is a recurrent problem in veterinary perinatology, and several factors can directly or indirectly culminate in neonatal death. One prime determinant of low vitality in animals is foetal hypoxia resulting from prolonged labour or dystocia. Factors such as foetal acidosis, metabolic and electrolyte imbalances, and asphyxia can quickly lead to neonatal death, while others are a consequence of low vitality in which the weak neonate cannot reach the teat and feed, thermoregulate, or breathe because of airway obstruction by meconium. Neonatal hypoxia can also lead to a failure of passive transfer and neonatal infections. The birth weight, the age of the dam, the size of the litter, and parity are also relevant vitality determinants. Scoring systems, similar to the Apgar score used with human babies, have been modified in veterinary neonatology to identify low vitality neonates in need of medical intervention. This review focuses on the vitality assessments and risk factors associated with neonatal mortality in puppies, calves and piglets. Also reviewed is the relationship of umbilical cord morphology and hypoxia with the premature passing of meconium into the amniotic sac and subsequent aspiration into the lungs. Veterinary literature shows a need to improve Apgar scores in animals by using blood gases and other clinical and laboratory tests. Also, it is necessary to better train veterinarians and personnel to identify low vitality neonates and when necessary to implement a rapid medical intervention.
The existing different modes of reproduction in monotremes, marsupials and placentals are the main source for our current understanding of the origin and evolution of the mammalian reproduction. The reproductive strategies and, in particular, the maturity states of the neonates differ remarkably between the three groups. Monotremes, for example, are the only extant mammals that lay eggs and incubate them for the last third of their embryonic development. In contrast, marsupials and placentals are viviparous and rely on intra-uterine development of the neonates via choriovitelline (mainly marsupials) and chorioallantoic (mainly placentals) placentae. The maturity of a newborn is closely linked to the parental care strategy once the neonate is born. The varying developmental degrees of neonates are the main focus of this study. Monotremes and marsupials produce highly altricial and nearly embryonic offspring. Placental mammals always give birth to more developed newborns with the widest range from altricial to precocial. The ability of a newborn to survive and grow in the environment it was born in depends highly on the degree of maturation of vital organs at the time of birth. Here, the anatomy of four neonates of the three major extant mammalian groups is compared. The basis for this study is histological and ultrastructural serial sections of a hatchling of Ornithorhynchus anatinus (Monotremata), and neonates of Monodelphis domestica (Marsupialia), Mesocricetus auratus (altricial Placentalia) and Macroscelides proboscideus (precocial Placentalia). Special attention was given to the developmental stages of the organs skin, lung, liver and kidney, which are considered crucial for the maintenance of vital functions. The state of the organs of newborn monotremes and marsupials are found to be able to support a minimum of vital functions outside the uterus. They are sufficient to survive, but without capacities for additional energetic challenges. The organs of the altricial placental neonate are further developed, able to support the maintenance of vital functions and short-term metabolic increase. The precocial placental newborn shows the most advanced state of organ development, to allow the maintenance of vital functions, stable thermoregulation and high energetic performance. The ancestral condition of a mammalian neonate is interpreted to be similar to the state of organ development found in the newborns of marsupials and monotremes. In comparison, the newborns of altricial and precocial placentals are derived from the ancestral state to a more mature developmental degree associated with advanced organ systems.