Mother–offspring recognition via contact calls in cattle, Bos taurus

Puppy whines mediate maternal behavior in domestic dogs

In mammals, offspring vocalizations typically encode information about identity and body condition, allowing parents to limit alloparenting and adjust care. But how do these vocalizations mediate parental behavior in species faced with the problem of rearing not one, but multiple offspring, such as domestic dogs? Comprehensive acoustic analyses of 4,400 whines recorded from 220 Beagle puppies in 40 litters revealed litter and individual (within litter) differences in call acoustic structure. By then playing resynthesized whines to mothers, we showed that they provided more care to their litters, and were more likely to carry the emitting loudspeaker to the nest, in response to whine variants derived from their own puppies than from strangers. Importantly, care provisioning was attenuated by experimentally moving the fundamental frequency (fo, perceived as pitch) of their own puppies' whines outside their litter-specific range. Within most litters, we found a negative relationship between puppies' whine fo and body weight. Consistent with this, playbacks showed that maternal care was stronger in response to high-pitched whine variants simulating relatively small offspring within their own litter's range compared to lower-pitched variants simulating larger offspring. We thus show that maternal care in a litter-rearing species relies on a dual assessment of offspring identity and condition, largely based on level-specific inter- and intra-litter variation in offspring call fo. This dual encoding system highlights how, even in a long-domesticated species, vocalizations reflect selective pressures to meet species-specific needs. Comparative work should now investigate whether similar communication systems have convergently evolved in other litter-rearing species.

Sensory Mechanisms of Parent-Offspring Recognition in Fishes, Amphibians, and Reptiles

Parental care is important for offspring survival and success. Recognition of offspring by parents is critical to ensure parents direct care behaviors at related offspring and minimize energy lost by caring for unrelated young. Offspring recognition of parents prevents possible aggressive interactions between young and unrelated adults and allows offspring to direct begging behaviors toward the correct adult. Despite its importance and widespread nature, much of the current research has focused on a small range of species, particularly mammals and birds. We review the existing literature on the sensory mechanisms of parent-offspring recognition in fishes, amphibians, and reptiles. Within these groups, there is diversity in the presence and strategies for parent-offspring recognition. Future studies should continue to identify these mechanisms, as well as the neural and endocrine underpinnings in non-model organisms to expand our knowledge of this behavior and inform our understanding of the evolution of parent-offspring recognition.

Potential for automatic detection of calving in beef cows grazing on rangelands from Global Navigate Satellite System collar data

Dystocia is one of the main causes of calf death around calving. In addition, peripartum deaths may occur due to other factors, such as weather or predators, especially in the case of grazing animals. Precision Livestock Farming (PLF) tools aimed at the automatic detection of calving may be useful for farmers, allowing cow assistance in case of dystocia or checking the condition of the cow-calf pair after calving. Such PLF systems are commercially available for dairy cows, but these tools are not suitable for rangelands, mainly due to power and connectivity constraints. Thus, since most commercial PLF tools for rangelands are based on Global Navigate Satellite System (GNSS) technology, the objective of this study was to design and evaluate several indicators built from data gathered with GNSS collars to characterise their potential for the detection of calving on rangelands. Location data from 57 cows, 42 of which calved during the study, were curated and analysed following a standardised procedure. Several indicators were calculated using two different strategies. The first approach consisted of having indicators that could be computed using the data of a single GNSS collar (cow indicators). The second strategy involved the use of data from several animals (herd indicators), which requires more animals to be monitored, but may allow the characterisation of social behaviour. Several indicators, such as the length of the daily trajectory or the sinuosity of cow path, showed significant differences between the pre- and postpartum periods, but no clear differences between calving day and previous days. Herd indicators, such as the distance to herd centroid or to the nearest peer were superior in terms of the detection of calving day, as cows showed isolation behaviour from 24 hours before calving. Relative indicators, i.e., the value of cow or herd indicators for the calving cow in relation to the average value of the same indicators for its herdmates, provided additional information on cow behaviour. For instance, according to the relative indicator for the change in daily trajectory, pregnant cows had a differential exploratory behaviour up to 14 days before calving. In conclusion, data from commercial GNSS collars proved to be useful for the computation of several indicators related to the occurrence of calving on rangelands. Some of those indicators showed changes from baseline values on the day before calving, which could serve to predict the onset of parturition.

Dairy Buffalo Behavior: Calving, Imprinting and Allosuckling

Maternal behavior, in water buffalo and other ruminants, is a set of patterns of a determined species, including calving, imprinting, and suckling. This behavior is mainly triggered by hormone concentration changes and their interactions with their respective receptors in the brain, particularly oxytocin. These chemical signals also influence mother-young bonding, a critical process for neonatal survival that develops during the first postpartum hours. Currently, dairy buffalo behavior during parturition has rarely been studied. For this reason, this review aims to analyze the existing scientific evidence regarding maternal behavior in water buffalo during calving. It will address the mechanisms of imprinting, maternal care, and allosuckling strategies that may influence the survival and health of calves.

Is maternal defensiveness of Gyr cows (Bos taurus indicus) related to parity and cows’ behaviors during the peripartum period?

The maternal care of cows can influence both the milk production and the performance of their calves, making this a topic of important relevance for the production industry that uses zebu cattle. The aims of this study were to 1) investigate the effects of parity on the behaviors of Gyr cows during the peripartum period; 2) characterize the maternal defensiveness of primiparous and multiparous cows towards handlers during the first handling of their calves; and 3) evaluate the relationships between cows’ behaviors at the peripartum period and maternal defensiveness. Thirty-one Gyr cows (primiparous and multiparous), from Empresa de Pesquisa Agropecuária de Minas Gerais (Brazil), were used. The animals were placed in a maternity paddock monitored by video cameras. The behaviors of the animals were collected in four periods: Pre-calving, Post-calving, First handling of calf and Post-handling. Primiparous cows presented more pain signs, reflected in arched spine (P = 0.05), and tended to move more (P = 0.07) than the multiparous in the Pre-calving period. Trends were observed for both Maternal Composite Score (P = 0.06) and Maternal Protective Behavior score (P = 0.06), indicating that both primiparous and multiparous were protective, but only multiparous cows were aggressive toward the caretakers on the first handling of their calves. The most protective cows spent more time eating during the prepartum period (P = 0.03), while the least attentive cows spent more time lying down (P = 0.02) in the prepartum period. The cows who nursed and stimulated their calves more were also calmer (P = 0.02) and more attentive (P = 0.01). In conclusion, the peripartum behaviors of Gyr cows were related to maternal care and maternal defensiveness. Multiparous cows tended to be more aggressive than primiparous cows at the time of the first handling of their calves.

The function and evolution of child-directed communication

Humans communicate with small children in unusual and highly conspicuous ways (child-directed communication (CDC)), which enhance social bonding and facilitate language acquisition. CDC-like inputs are also reported for some vocally learning animals, suggesting similar functions in facilitating communicative competence. However, adult great apes, our closest living relatives, rarely signal to their infants, implicating communication surrounding the infant as the main input for infant great apes and early humans. Given cross-cultural variation in the amount and structure of CDC, we suggest that child-surrounding communication (CSC) provides essential compensatory input when CDC is less prevalent-a paramount topic for future studies.

Parental Behavior in Bovines

After approximately 9 months, cows give birth to one calf. They usually try to separate from the herd if kept outdoors, but this depends on the possibilities to hide. When the calf is born, the cow immediately stands up and starts licking the calf, and this is most intense for the first hour. During this time, the cow is very protective of her calf and may attack anyone trying to come close to it, especially if the cow is not so used to human handling. The calf tries to stand up and falls in the beginning, but it usually stands about half an hour later. Once standing, the calf searches for the udder, and after approximately 2 h, the calf is suckling the colostrum from the cow's teats. The calf is born without an immune defense, and it, therefore, needs to suckle enough colostrum from the cow to get protection against infections. If the calf does not succeed in suckling within 4-6 h after birth, the farmer must milk the cow and give the calf at least 2-4 l of colostrum in a teat bottle. If the farmer has frozen colostrum of good quality in the freezer, and it is either difficult to milk the cow or her colostrum is of too low quality, the frozen colostrum can be warmed up and given to the calf. Beef calves are usually allowed to stay with their mother until they are 6-8 months old, when they are separated from the cow and then weaned. Dairy calves are usually separated from their mother immediately or within a few days after birth and raised by artificial milk feeding. In the beginning or during the whole milk period (6-12 weeks), they may be kept individually indoors in crates or outdoors in hutches. After weaning, they are usually group housed.

Neurophysiological Mechanisms of Mother-Young Bonding in Buffalo and Other Farm Animals

Simple Summary

The present paper reviews the importance of bonding for the survival and well-being in the cow–calf relationship. The review focuses on buffaloes and information from other species is used for comparison or to find more general patterns in the absence of specific sources. Differences between several farm species are also described, focusing on the role played by the sensory stimuli during the sensitive period after birth. How bonding can be classified according to the predominant senses used by different species, the importance of learning (i.e., imprinting) in the development of mother–young relationship, and the neurobiological mechanisms involved are also delineated. Finally, some examples of the main factors that can affect the mother–young relationship in the field are given. By understanding the imprinting at brain level, as well as the relationship with behavior, we gain a deeper insight into the critical role that experience, and environmental factors play in shaping the development of the mother–offspring bond.

Abstract

In buffaloes and other mammalian farm species, the mother provides food and protection to the young, but she is also the main source of behavioral and social learning for the offspring. It is important that mother and young establish a bond based on a learning mechanism defined as “imprinting” early after parturition during the sensitive period, on which the welfare and survival of the offspring will depend. This review aims to summarize and discuss current knowledge regarding the imprinting process, the neurobiological pathways that are triggered during this sensitive period, and the development of the cow–calf bond. Touch, hearing, vision, and smell seem to be the predominant senses involved during imprinting in buffaloes and other mammalian farm species. In buffalo, bonding is very particular due to the expression of specific behaviors, such as allo-suckling and communal rearing. In general, imprinting and the subsequent bond may be affected by the lack of experience of the mothers or dystocic parturitions, which occur most frequently with male calves and in primiparous dams. The main problems in the development of this process include lack of seeking a protected and isolated place to give birth; moving from the birth-site after parturition; insufficient postpartum care; aversion or aggressiveness towards the newborn, or abandonment of the newborn. The process can develop differently according to the species. However, the correct development of the cow–calf relationship represents, regardless of the species, a key factor for their fitness.

Vocal production in postpartum dairy cows: Temporal organization and association with maternal and stress behaviors

Mammalian vocalizations can encode contextual information in both the spectrographic components of their individual vocal units and in their temporal organization. Here we observed 23 Holstein-Friesian dairy cows immediately after birth during interactions with their calf and when their calf was separated to the other side of a fence line. We investigated whether the vocalizations emitted in these postpartum contexts would vary temporally. We also described the maternal and stress behaviors preceding and following postpartum vocal production using kinematic diagrams and characterized call sequence structure. The kinematic diagrams highlight the disruption of maternal responses caused by calf separation and show that behavioral and vocal patterns varied according to the cows' emotional states and proximity to the calf in both contexts. During calf interactions, cows mainly produced closed-mouth calls simultaneous to licking their calf, whereas an escalation of stress responses was observed during calf separation, with the cows approaching the fence line, becoming alert to the calf, and emitting more mixed and open-mouth calls. Call sequences were similarly structured across contexts, mostly containing repetitions of a single call type, with a mean interval of 0.57 s between calls and a greater cumulative vocalization duration, attributed to an increased number of vocal units per sequence. Overall, calf separation was associated with a greater proportion of calls emitted as a sequence (inverse of single isolated calls), a shorter interval between separate call sequences, and a greater number of vocal units per sequence, compared with calf interactions. These temporal vocal features varied predictably with the high stress expression from cows during calf separation and may represent temporal modulations of emotional expression. Despite the noisy farm soundscape, empirical call type and temporal vocal features were easy to measure; thus, findings could be applied to future cattle studies wishing to analyze vocalizations for on-farm welfare assessments.

Talking to Cows: Reactions to Different Auditory Stimuli During Gentle Human-Animal Interactions

The quality of the animal-human relationship and, consequently, the welfare of animals can be improved by gentle interactions such as stroking and talking. The perception of different stimuli during these interactions likely plays a key role in their emotional experience, but studies are scarce. During experiments, the standardization of verbal stimuli could be increased by using a recording. However, the use of a playback might influence the perception differently than "live" talking, which is closer to on-farm practice. Thus, we compared heifers' (n = 28) reactions to stroking while an experimenter was talking soothingly ("live") or while a recording of the experimenter talking soothingly was played ("playback"). Each animal was tested three times per condition and each trial comprised three phases: pre-stimulus, stimulus (stroking and talking) and post-stimulus. In both conditions, similar phrases with positive content were spoken calmly, using long low-pitched vowels. All tests were video recorded and analyzed for behaviors associated with different affective states. Effects on the heifers' cardiac parameters were assessed using analysis of heart rate variability. Independently of the auditory stimuli, longer durations of neck stretching occurred during stroking, supporting our hypothesis of a positive perception of stroking. Observation of ear positions revealed longer durations of the "back up" position and less ear flicking and changes of ear positions during stroking. The predicted decrease in HR during stroking was not confirmed; instead we found a slightly increased mean HR during stroking with a subsequent decrease in HR, which was stronger after stroking with live talking. In combination with differences in HRV parameters, our findings suggest that live talking might have been more pleasurable to the animals and had a stronger relaxing effect than "playback." The results regarding the effects of the degree of standardization of the stimulus on the variability of the data were inconclusive. We thus conclude that the use of recorded auditory stimuli to promote positive affective states during human-animal interactions in experimental settings is possible, but not necessarily preferable.

Vocal individuality of Holstein-Friesian cattle is maintained across putatively positive and negative farming contexts

Cattle mother-offspring contact calls encode individual-identity information; however, it is unknown whether cattle are able to maintain individuality when vocalising to familiar conspecifics over other positively and negatively valenced farming contexts. Accordingly, we recorded 333 high-frequency vocalisations from 13 Holstein-Friesian heifers during oestrus and anticipation of feed (putatively positive), as well as denied feed access and upon both physical and physical & visual isolation from conspecifics (putatively negative). We measured 21 source-related and nonlinear vocal parameters and stepwise discriminant function analyses (DFA) were performed. Calls were divided into positive (n = 170) and negative valence (n = 163) with each valence acting as a 'training set' to classify calls in the oppositely valenced 'test set'. Furthermore, MANOVAs were conducted to determine which vocal parameters were implicated in individual distinctiveness. Within the putatively positive 'training set', the cross-validated DFA correctly classified 68.2% of the putatively positive calls and 52.1% of the putatively negative calls to the correct individual, respectively. Within the putatively negative 'training set', the cross-validated DFA correctly assigned 60.1% of putatively negative calls and 49.4% of putatively positive calls to the correct individual, respectively. All DFAs exceeded chance expectations indicating that vocal individuality of high-frequency calls is maintained across putatively positive and negative valence, with all vocal parameters except subharmonics responsible for this individual distinctiveness. This study shows that cattle vocal individuality of high-frequency calls is stable across different emotionally loaded farming contexts. Individual distinctiveness is likely to attract social support from conspecifics, and knowledge of these individuality cues could assist farmers in detecting individual cattle for welfare or production purposes.

Begging behavior as an honest signal of need and parent-offspring association during the postfledging dependency period

Honest signaling mechanisms can function to appropriate care to hungry offspring and avoid misdirected care of unrelated offspring. Begging, the behavior by which offspring solicit food and parental care, may be an honest signaling mechanism for need, as well as association of parents and offspring. Roseate terns (Sterna dougallii) exhibit prolonged parental care during the postbreeding staging period, offering an ideal system in which to study begging as an honest signaling mechanism. We conducted focal sampling during two premigratory staging seasons (2014 and 2015) at Cape Cod National Seashore, Massachusetts, USA to determine whether postfledging tern begging behavior was an honest signal for need and parent-offspring association. Based on honest signaling theory, we expected begging behavior to be highest during times of high perceived need, and we expected to see a decrease in begging behavior as young terns became increasingly independent of the care-giving parent. Also, we predicted that young terns would be more likely to beg at parents than nonparents. We found that young roseate terns begged at their parents more often than nonparents; however, they did not always beg at parents. Model predictions of begging probability showed a linear relationship between begging and time of day and date of season, such that begging increased with time of day and decreased with date of season, respectively. Our results provide evidence for honest parent-offspring interactions and are inconsistent with parent-offspring conflict theory but suggest that begging may play a complex role in postfledging parent-offspring interactions.

OPEN RESEARCH BADGES

This article has been awarded Open Data, Open materials Badges. All materials and data are publicly accessible via the Open Science Framework at https://doi.org/10.5281/zenodo.2656718.

Automated bioacoustics: methods in ecology and conservation and their potential for animal welfare monitoring

Vocalizations carry emotional, physiological and individual information. This suggests that they may serve as potentially useful indicators for inferring animal welfare. At the same time, automated methods for analysing and classifying sound have developed rapidly, particularly in the fields of ecology, conservation and sound scene classification. These methods are already used to automatically classify animal vocalizations, for example, in identifying animal species and estimating numbers of individuals. Despite this potential, they have not yet found widespread application in animal welfare monitoring. In this review, we first discuss current trends in sound analysis for ecology, conservation and sound classification. Following this, we detail the vocalizations produced by three of the most important farm livestock species: chickens ( Gallus gallus domesticus), pigs ( Sus scrofa domesticus) and cattle ( Bos taurus). Finally, we describe how these methods can be applied to monitor animal welfare with new potential for developing automated methods for large-scale farming.

The role of familiarity in signaller-receiver interactions

In animal communication, individuals of species exhibiting individual recognition of conspecifics with whom they have repeated interactions, receive signals not only from unfamiliar conspecifics, but also from individuals with whom they have prior experience. Empirical evidence suggests that familiarity with a specific signaller aids receivers in interpreting that signaller's signals, but there has been little theoretical work on this effect. Here, we develop a Bayesian decision-making model and apply it to the well-studied systems of primate ovulation signals. We compare the siring probability of learner males versus non-learner males, based on variation in their assessment of the best time to mate and mate-guard females. We compare males of different dominance ranks, and vary the number of females, and their cycle synchrony. We find strong fitness advantages for learners, which manifest very quickly. Receivers do not have to see the full range of a signaller's signals in order to start gaining familiarity benefits. Reproductive asynchrony and increasing the number of females both enhance learning advantages. We provide theoretical evidence for a strong advantage to specific learning of a signaller's range of signals in signalling systems. Our results have broad implications, not only for understanding communication, but in elucidating additional fitness benefits to group-living, the evolution of individual recognition, and other characteristics of animal behavioural biology.

Looking on the Bright Side of Livestock Emotions-the Potential of Their Transmission to Promote Positive Welfare

Emotions can be defined as an individual's affective reaction to an external and/or internal event that, in turn, generates a simultaneous cascade of behavioral, physiological, and cognitive changes. Those changes that can be perceived by conspecifics have the potential to also affect other's emotional states, a process labeled as "emotional contagion." Especially in the case of gregarious species, such as livestock, emotional contagion can have an impact on the whole group by, for instance, improving group coordination and strengthening social bonds. We noticed that the current trend of research on emotions in livestock, i.e., investigating affective states as a tool to assess and improve animal welfare, appears to be unbalanced. A majority of studies focuses on the individual rather than the social component of emotions. In this paper, we highlight current limitations in the latter line of research and suggest a stronger emphasis on the mechanisms of how emotions in livestock are transmitted and shared, which could serve as a promising tool to synergistically enhance the welfare of all individuals within a group.

Divergent coevolutionary trajectories in parent-offspring interactions and discrimination against brood parasites revealed by interspecific cross-fostering

In animal families, parents are expected to adapt to their offspring's traits, and offspring, in turn, are expected to adapt to the environment circumscribed by their parents. However, whether such coevolutionary trajectories differ between closely related species is poorly understood. Here, we employ interspecific cross-fostering in three species of burying beetles, Nicrophorus orbicollis, Nicrophorus pustulatus and Nicrophorus vespilloides, to test for divergent co-adaptation among species with different degrees of offspring dependency on parental care, and to test whether they are able to discriminate against interspecific parasites. We found that offspring survival was always higher when offspring were reared by conspecific rather than heterospecific parents. In the case of N. orbicollis raising N. pustulatus, none of the larvae survived. Overall, these results indicate that parent and offspring traits have diverged between species, and that the differential survival of conspecific and heterospecific larvae is because of improper matching of co-adapted traits, or, in the case of N. orbicollis with larval N. pustulatus, because of selection on parents to recognize and destroy interspecific brood parasites. We suggest that burying beetles experiencing a high risk of brood parasitism have evolved direct recognition mechanisms that enable them to selectively kill larvae of potential brood parasites.

Prepartum Maternal Behavior of Domesticated Cattle: A Comparison with Managed, Feral, and Wild Ungulates

The event of giving birth is an essential part of animal production. In dairy cattle production, there are substantial economical and welfare-related challenges arising around the time of parturition, and hence increased focus on efficient management of the calving cow. Drawing on the research literature on prepartum maternal behavior, this review compares cattle to other members of the ungulate clade with the aim of understanding the biological basis of bovine prepartum behavior with main emphasis on dairy cows. Ultimately, this knowledge may be used in future development of housing systems and recommendations for the management of calving cows. Maternal prepartum behavior varies among species, but the final goal of ungulate mothers is the same: ensuring a calm parturition and optimal environment for the onset of postpartum maternal behavior by locating an appropriate birth site, with low risk of predators, disturbances and mistaken identity of offspring. Features of chosen birth sites vary among species and depend largely on the environment, as ungulate females display a considerable ability to adapt to their surroundings. However, within commercial housing conditions in dairy production, the animals’ ability to adapt behaviorally appears to be challenged. Confinement alongside high stocking densities leave little room to express birth-site selection behavior, posing a high risk of agonistic social behavior, disturbances, and mismothering, as well as exposure to olfactory cues influencing both prepartum and postpartum maternal behavior. Dairy cows are thus exposed to several factors in a commercial calving environment, which may thwart their maternal motivations and influence their behavior. In addition, prepartum cattle may be more affected by olfactory cues than other ungulate species (e.g., sheep) because they are attracted to birth fluids already before calving. Hence, providing dairy cows with an environment where they can perform the maternal behavior they are motivated for, may aid a calm and secure calving and provide optimal surroundings for postpartum maternal behavior. Future research should focus on designing motivation-based housing systems allowing freedom to express prepartum maternal behavior and investigate in more detail the effects of the environment on the welfare of calving cows and their offspring.

Using temporal associations to determine maternal parentage in extensive beef herds

The assignment of maternal parentage, although time-consuming and expensive using traditional methods, is essential for genetic improvement. Within the sheep industry the recording of time-based (temporal) associations without human intervention has been routinely used to derive maternal parentage, however it has not been researched in extensive beef production systems. To determine whether temporal associations could be used to assign maternal parentage, cows and calves had their identity recorded as they walked to water over a 27-day trial. Two methods of association were investigated, being the half-weight index and the time difference between a cow and calf having their identity recorded. The half-weight index, which is a measure of the number of times two individuals are recorded together, correctly assigned greater than 90% of maternal pairs. When investigating the duration of data recording it was shown that 85% of maternal parentage could be achieved within only 21 days. Further work is required to determine the effect of calf age, herd and paddock size; however, the results showed that the half-weight index method of determining maternal associations is a labour-saving and accurate alternative to traditional methods used to identify maternal parentage.

Remarkable vocal identity in wild-living mother and neonate saiga antelopes: a specialization for breeding in huge aggregations?

Saiga antelopes Saiga tatarica tatarica give birth in large aggregations, and offspring follow the herd soon after birth. Herding is advantageous as anti-predator strategy; however, communication between mothers and neonates is strongly complicated in large aggregations. Individual series of nasal and oral contact calls of mother and neonate saiga antelopes were selected from recordings made with automated recording systems placed near the hiding neonates on the saiga breeding grounds in Northern Kazakhstan during synchronized parturitions of 30,000 calving females. We used for comparison of the acoustic structure of nasal and oral contact calls 168 nasal calls of 18 mothers, 192 oral calls of 21 mothers, 78 nasal calls of 16 neonates, and 197 oral calls of 22 neonates. In the oral calls of either mothers or neonates, formant frequencies were higher and the duration was longer than in the nasal calls, whereas fundamental frequencies did not differ between oral and nasal calls. Discriminant function analysis (DFA) based on six acoustic variables, accurately classified individual identity for 99.4% of oral calls of 18 mothers, for 89.3% of nasal calls of 18 mothers, and for 94.4% of oral calls of 18 neonates. The average value of correct classification to individual was higher in mother oral than in mother nasal calls and in mother oral calls than in neonate oral calls; no significant difference was observed between mother nasal and neonate oral calls. Variables mainly responsible for vocal identity were the fundamental frequency and the second and third formants in either mothers or neonates, and in either nasal or oral calls. The high vocal identity of mothers and neonates suggests a powerful potential for the mutual mother-offspring recognition in dense aggregations of saiga antelopes as an important component of their survival strategy.