Suckling Bouts Research Articles

FEATURES OF SUCKLING BEHAVIOUR OF GAZELLA MARICA FAWNS IN SEMI-CAPTIVE CONDITIONS

In ungulate species, adequate and balanced nutrition for newborns is crucial, and it is primarily achieved through effective suckling by their mothers. This study investigated the sucking behavior of Gazella marica fawns under semi-captive conditions. Observations were conducted using the Focal Animal Sampling Method, and in total 177 gazelles were observed in the study period. The Kruskal-Wallis test was employed to analyze the duration between long suckling bouts and total suckling duration, while the Mann-Whitney U test was used for pairwise comparisons of suckling duration, duration between short suckling bouts, and total suckling duration. Results showed a significant difference in sucking duration between twin fawns (14.1 seconds) and single fawns (16.5 seconds) (P < 0.001). Additionally, the average sucking duration was higher in May compared to other months (P < 0.001). As the fawns matured, the frequency of suckling bouts increased, with the duration between long suckling bouts reaching 321 minutes in August (P < 0.001). However, no significant differences were observed in the total suckling duration between twin and single fawns (P > 0.05). These findings indicate some differences in the suckling behavior of gazelle fawns in semi-captivity compared to those in the wild. Further research on gazelles under consistent conditions across different breeding stations is necessary to fully understand the suckling behavior of gazelle fawns. Keywords: Gazella fawns, average suckling duration, suckling bouts, total suckling.

The Role of Play in the Social Development of Grey Seal (Halichoerus grypus) Pups with Comparative Notes on the Harbour Seal (Phoca vitulina).

Juvenile grey seals are known to be highly social, interacting with contact behaviours interpreted as gentle play. However, minimal sociality of pups with their mothers and among weaned pups has been suggested. The present study aimed to observe the natural social interactions of pups to track the early ontogeny of their sociality. Pup behaviour at a salt marsh colony on the east coast of England was video-recorded. Pups interacted with their mothers around suckling bouts and after weaning as they gathered around pools. The records were transcribed to spreadsheets in 30 s time segments to estimate the frequency and co-occurrence of different behaviours. Mother-pup interaction comprised nosing contacts and sometimes contact play, involving one laying the head and fore-flipper over the other. Initial weaned pup encounters involved tentative nosing and defensive splashing, indicating contact shyness. However, socially orientated locomotor play, supine posturing, and exaggerated raising of fore- and hind-flippers led to reduced shyness and pups following one another towards the sea. Archive data on subadult interactions and on harbour seal behaviours were re-analysed. Gentle play-like contact between mother-pup, juvenile, and adult pairs is interpreted here as a universal mode of social bonding, underscoring the social structure of both grey and harbour seals.

Behaviour of farmed fallow deer fawns in the rearing period depends on weather conditions

Farmed fallow deer (Dama dama) fawns need to receive care and help from their mothers and be stimulated by other individuals, including their peers. This helps them to learn to live in a group, establish their place in the herd, acquire food, perceive dangers, survive, and initiate reproductive behavior. Adequate analysis of changes in behaviour conducted by deer breeders can be helpful in management of the animals. Furthermore, the knowledge of the time when any disturbance in the natural behaviour of animals should be avoided may contribute to improvement of their welfare. The aim of the research was to analyse the behaviour of fawns in the early rearing period and the influence of weather conditions. The observations were conducted in July 2017 and 2018. The fawns most frequently performed the observed activities in the morning and evening. The ritual playing and suckling bouts were most often noted in the evening. With an increase in air temperature and a decrease in humidity, the young fallow deer followed the doe and vocalized to call the mother, probably to persuade her to hide in a shaded place. A higher frequency of suckling was noted at an increased air temperature and humidity, but the suckling time was reduced with the increasing air temperature. A greater wind speed was associated with a higher frequency of allosuckling. The study showed that the natural behaviour of fawns, which has an impact on their functioning in the herd, should not be disturbed in the morning and evening.

Microglia depletion prevents lactation by inhibition of prolactin secretion

Microglial cells were eliminated from the brain with sustained 3-4weeks long inhibition of colony stimulating factor 1 receptor by Pexidartinib 3397 (PLX3397). The prepartum treated mice mothers did not feed their pups after parturition. The pups of mothers treated orally only in the postpartum period starting immediately after parturition showed reduced body weight by 15.5± 0.22 postnatal days as the treatment progressed without the mothers showing altered caring behaviors. The apparent weight gain of foster pups during a suckling bout was reduced in mother mice fed by PLX3397-containing diet and also in rat dams following sustained intracerebroventricular infusion of PLX3397 in a separate experiment suggesting that lactation was affected by the reduced number of microglia. Prolactin secretion and signaling were markedly reduced in PLX3397-treated mothers. The results suggest that microglial cells are required for prolactin secretion and lactation whereas maternal motivation may not be directly affected by microglia.

Piglets’ behaviour and performance in relation to sow characteristics

The importance of maternal care in commercial pig production is largely ignored. The sow has little possibility to interact with her piglets, and piglets are often subjected to early weaning or artificial rearing. This study aimed to investigate aspects of physiological and behavioural maternal provisioning that contribute to offspring outcomes. We hypothesised that better maternal care and nutritional provisioning would relate positively to piglet immunity, growth and behaviour. Nineteen sows and their litters were studied in free-farrowing pens. Oxytocin and tumour necrosis factor-α in colostrum/milk and salivary cortisol were sampled from sows throughout lactation. Sows were assessed for dominance rank, response to handling, maternal defensiveness, suckling initiation and termination, posture and sow-piglet contact. Piglets were weighed, measured for body mass index (BMI) and sampled for blood (Immunoglobulin G; at birth). After weaning, they experienced a human approach test (HAT) and novel object test. Correlations were explored between individual sow characteristics, individual piglet outcomes, and between sow characteristics and piglet outcomes averaged by litter. Significant correlations between sow and piglet factors were analysed at the litter level in mixed models with piglet outcomes as response variables and sow characteristics as predictor variables, while accounting for sow parity, litter size and batch. Litters grew faster when their sow had lower cortisol values (P = 0.03), while sows with lower cortisol levels had more successful suckling bouts and engaged in greater amounts of sow-piglet contact. Litters had a lower BMI at weaning when the sow had a higher milk fat percentage at d3. Litters of the most dominant sows took longer to approach the human in the HAT, while litters of sows with higher cortisol at d0 took longer to approach the novel object when assessed on correlations (r = 0.82, P < 0.001) but not when the model accounted for parity and litter size (P = 0.35). Only some of the measured nutritive and non-nutritive sow factors influenced litter performance and behaviour, with parity and litter size also playing a role. Given the continued increase in litter size, but also the interest in loose-housed lactation pens for sows, further research on sows’ maternal investment and how it can be optimised is warranted.

Evidence of three distinct lactation stages in nursing gazelles: Implications on maternal behaviour assessment

Studying suckling behaviour has been used to understand parent-offspring conflict in mammals when the mother adjusts the amount of resources invested into an offspring during the lactation period. However, most studies report this information as a by-product of studying other types of suckling behaviour, like allosuckling. We aimed to understand this decision-making process by analysing the filial suckling bouts where the interval from the previous filial suckling bout was known. We used a captive population of threatened dorcas gazelles (Gazella dorcas) as a model species. Our findings showed that the lactation period in dorcas gazelle is characterised by three distinctive behavioural stages, where the behaviour of mother and calf changes rather fast, despite the progressive change in suckling duration. Early lactation (EL), when suckling bouts are always terminated by the calf; mid lactation (ML), when both the mother and the calf indistinctly may end up the suckling bouts; and late lactation (LL), when it is the mother who unfailingly ends lactation events. Also, we found evidence of male-biased maternal investment, as mothers tended to offer more investment towards male calves when suckling Additionally, we confirmed a compensational mechanism whereby calves born later in the birth season were suckled for longer (in terms of duration of suckling bouts) than calves born earlier, resulting in similar weaning dates for all studied calves. Therefore, many aspects may be overlooked if the influence of allosuckling on standard suckling is not considered when analysing suckling behaviour. Thus, we suggest this method of standard suckling behaviour analysis, where all behaviours which may alter the calves' demands and mothers' resources are removed (i.e., suckling attempts, allosuckling, and suckling after allosuckling).

Effects of lamb sex and ewe parity on suckling-related neonatal behaviors and weaning weight of small-tailed han lambs

Suckling behavior is essential for the growth, health, and welfare of the lamb. The factors that influence the suckling-related behavior varied across breeds, and they remain unclear in Small-tailed Han lamb. This study aims to investigate the effects of ewe parity, lamb sex, and birth order on the suckling-related behaviors of Small-tailed Han lamb. The neonatal behaviors of 36 lambs were observed during the first week after birth using focal-animal sampling methods, and the levels of cholecystokinin (CCK), endogenous opioid peptides and growth hormone (GH) were measured with ELISA methods before weaning. Results showed that male lambs began standing and suckling behaviors earlier than female lambs, and the duration of each suckling bout was longer in male lambs (P < 0.05). Lambs born to multiparous ewes more frequently suckled and attempted to stand earlier than lambs from primiparous ewes (P < 0.05). The weaning weights of male lambs and lambs from multiparous ewes were heavier, and the serum levels of CCK, opioid peptides, and GH were sometimes higher in these lambs before weaning (P < 0.05). Meanwhile, lamb birth order has no significant effect on the suckling-related behaviors of lambs (P > 0.05). In addition, the suckling-related behaviors of male lamb and lambs born to multiparous ewes were found to strongly correlate with each other. In conclusion, lamb sex and ewe parity could affect the suckling-related behaviors and weaning weights of Small-tailed Han lambs. Moreover, male lambs and lambs born to multiparous ewes seemed to have better suckling-related behaviors. Many of these behaviors were highly connected with one another. These phenomena may be related to the higher serum levels of CCK, opioid peptides, and GH. The effects of lamb sex on suckling-related behaviors were different from those of other breeds in previous research. The male lambs were observed to initiate sucking-related behaviors earlier in this study. Our findings will also help in extensively understanding the variability in the effects of these factors on suckling-related behavior across sheep breeds.

Variation in piglet body weight gain and feed intake during a 9-week lactation in a multi-suckling system

A multi-suckling (MS) system for sows and piglets has been developed aiming to improve animal welfare. In this system, large variation in BW gain exists between piglets up to weaning at 9 weeks of age. We aimed to study the causes of variation in BW gain and DM intake of solid feed (DFI) (piglet + sow feed) of piglets during lactation in the MS system. A total of 15 sows and 60 focal piglets across three batches were studied. Individual intake of piglet and sow feed was measured by the dual marker method, and multiple variables were recorded. Multiple linear regression analysis with forward selection was conducted on BW gain and DFI after correcting for piglet sex and batch, using multiple explanatory variables including genetic background, birthweight (BiW), DM feed intake, behaviours and number of skin lesions. These factors jointly explained less than 45 % and 21 % of the variation in BW gain and DFI, respectively. In weeks 2–4, variation in BW gain was mainly explained by BiW (12.0 %) and play and nosing behaviours (7.6 %). In weeks 4–6 and 6–8, it was largely explained by DM intake of piglet feed with 15.1 % and 25.9 %, respectively. Individual variation in DFI in weeks 2–4 was explained by the presence at front and middle teats during suckling bouts (2.9 %), in weeks 4–6 by BiW (9.6 %), and in weeks 6–8 by the number of skin lesions (5.1 %). The unexplained variation in BW gain and DFI warrants further investigation.

Effect of udder morphology on milk yield and suckling behaviour of patanwadi lambs

A study was conducted to determine the relationship between udder traits, milk yield and lamb suckling behaviour in Patanwadi lambs (n=30) during August to October 2019. The mean body condition score was significantly (p<0.05) less at 40 and 60 days of lactation The average udder tissue content score, udder circumference, udder depth and udder width showed significant (p<0.05) difference between 1st (4.37±0.14, 41.80±0.87cm, 16.90±0.53 cm and 14.93±0.28 cm) and 60th (3.23±0.10, 35.47±0.73 cm, 14.33±0.33 cm and 13.43±0.27 cm) days of lactation. The total sucking duration, sucking frequency, sucking bout, suckling bout frequency, mean bout duration and hindering attempts by dam significantly (p<0.01) decreased from 1st (5.24±0.22, 4.49±0.20/min, 9.16±0.39, 2.62±0.14/min, 45.27±2.09 sec and 1.30±0.31no) to 60th (1.60±0.11, 1.59±0.11/min, 3.67±0.17, 0.94±0.07/min, 18.01±1.61sec and 7.33±0.31) day of lactation while number of sucking attempts non-significantly decreased during the same period. The average daily milk yield of sheep significantly (p<0.01) decreased from 897±35.47g in 1st day to 686±33.56g in 60th day of lactation. The total sucking duration, sucking number and frequency, sucking bout number and frequency and mean bout duration were significantly (p<0.05) correlated with milk yield, udder tissue content and overall shape or suspension of udder. It was inferred that udder conformation and morphology affect suckling behaviour of lambs, dams having symmetrical, wider and capacious udders with clear demarcation between left and right mammary quarters favoured longer sucking durations with a greater number and longer sucking bouts in lambs.

Recording cattle maternal behaviour using proximity loggers and tri-axial accelerometers

The close proximities between cow–calf pairs and suckling behaviour of calves are very important for calf survival; as the cow provides nutrients (milk) and protection to the calf from predators and teaches various important life survival skills. In extensive production systems, with the help of technology précised and accurate data of animal behaviour can be obtained. This study used tri-axial accelerometers and proximity loggers to record the time spent in suckling and in close proximity by cow–calf pairs, respectively. The relationship between these two behaviours and similarities in circadian variations were explored. The use of proximity loggers as a proxy for accelerometers to record suckling behaviour was investigated. The effect of sex, age, birth weight of calves; weight of both cows and calves at the time of data collection and parity of cows on the time spent by cow–calf pairs in close proximity was determined. During the 2015–16 breeding season, 28 B. taurus (Belmont Red) cow–calf pairs were studied for 12 days. Proximity logging collars were fitted to all cows and calves, while calves were also fitted with halters containing tri-axial accelerometers on the right-side strap. The results showed that calves spent on average 102.5 ± 13.26 min per day in close proximity to their dams, with the average duration of each close proximity was 0.7 ± 0.07 min, and the average number of close proximities in 24 h was 128.5 ± 16.98. Calves spent a total of 73.3 ± 7.36 min per day suckling, with an average duration of each suckling bout of 9.4 ± 0.39 min, and an average number of 7.7 ± 0.67 suckling bouts in 24 h. There was no relation found between any parameters of time spent in close proximity with time spent in suckling. All the suckling events recorded by accelerometers were not recorded as close proximity by proximity loggers due to interrupted signals, confirming that proximity loggers were not a suitable proxy to record the suckling bouts. The frequency, average duration and total duration of contacts between cow–calf pairs were greater during non-suckling events compared with suckling events. Three similar peaks in circadian pattern of frequency of contact and suckling were found. The calves’ age, birth weight, weight of both calves and cows at the time of data collection and parities of cows had no effect on their close proximity. The female calves contacted with their dams more frequently than male calves.

Further behavioural parameters support reciprocity and milk theft as explanations for giraffe allonursing

Suckling of a non-filial calf, or allosuckling, is an extreme case of allomaternal care in mammals. There have been many hypotheses postulated in an attempt to explain this behaviour; however, the supporting evidence differs, together with the conclusions drawn from the investigated variables. Previously, suckling bout rejection was analysed, and the milk theft and reciprocity hypotheses were both determined as the most appropriate explanation of allosuckling in giraffe. In this study, seven hypotheses were tested using different behavioural parameters, namely suckling bout frequency, suckling bout duration, and time spent suckling. It is well-documented that these parameters are associated with various aspects in ungulate biology; for example, suckling rejection typically reflects milk intake and parent–offspring conflict, whereas the suckling bout duration and frequency is associated with social behaviours (affiliation, bonding, social stress). In total, 22 nursing females and 47 suckling calves were observed, in four Czech zoos during a five-year period. The correlation of the observed parameters between the reciprocal female-calf dyads was found to be in line with the reciprocity hypothesis. In addition, non-filial calves tried to steal the milk from non-maternal females, supporting the milk theft hypothesis. Thus, the results support both the reciprocity and milk-theft hypotheses as the most plausible explanation of allosuckling in giraffe, and illustrates the importance of using suckling bout duration and frequency, and the time spent suckling, as behavioural parameters that may aid in explaining the extremity of maternal investment, such as allosuckling.

Does social facilitation affect suckling behaviour in zebras?

Many recent studies show that synchronisation of various behaviours are advantageous for group-living mammals. However, studies on synchronisation of suckling behaviour inmonotocous species are nearly absent. We observed 49 individual foals of three zebra species in Dvůr Králové Zoo, and recorded a total of 5 890 suckling bouts, almost one fifth (1 036) of which were synchronised (defined as at least two bouts overlapping at the same time). We found that synchronised suckling bouts lasted longer and were less likely to be terminated by the mother than non-synchronised ones. This is in line with social facilitation theory. In addition the occurrence of synchronised suckling bout differed interspecifically. In plains (Equus quagga) and mountain zebra (E. zebra) the probability of synchronised bouts increased with increasing numbers of foals, whereas the opposite result was found in Grevy’s zebra (E. grevyi). We suggest that the interspecific differences may reflect differences in social organisation of respective species as suckling synchronisation rate was higher in species that form nurseries in the wild.

Suckling behaviour of West African dwarf goat kids

During suckling, goat kids exhibit different kinds of behavior which could be germane to their general performance. The objective of this study was to determine suckling behaviour of West African dwarf (WAD) goat kids with respect to some behavioural measurements. A total number of 21 WAD does comprising of 1st and 2nd parity with live weight range of 9.5kg-16.5kg with a total of 26 kids (12males and 14females) in a small holder dairy goat were used. Data on suckling behaviour (suckling bout, duration of suckling and number of butts during suckling) was monitored to investigate the effect of birth type (singleton and twin) and kid sex (male and female). Behaviours were observed twice/day i.e. in the morning (7:00-8.30 am) and evening (4:30-6:00pm), 2 days/week starting from the 2nd week after kidding for 7 weeks. Suckling bout, duration of suckling and number of butts during suckling was greater in twin than in singleton. Kid sex had no significant effect on all behavioural parameters monitored. However, significant positive correlations were observed between suckling bout and number of butts during suckling, between suckling bouts and duration of suckling and between duration of suckling and number of butts during suckling. In conclusion, suckling behaviours in WAD kids were dependent on the birth type and not sex of the kids.

Negative correlation of suckling behaviour and foal weight gain during the first week after birth

After their birth, foals are usually housed with and nursed by their mares. Because a foal’s growth and survival depend greatly on the mare’s milk for a certain time after birth, it is said that observations of suckling behaviour can indicate a foal’s growth. Nevertheless, the results of earlier studies suggest that foal suckling behaviour is not a useful predictor of milk intake. This study investigated the relationship between suckling behaviour and foal weight gain, referring to several definitions of suckling bouts and sufficient sampling methods, and including several confounding factors in the analyses. Observations were made of 17 mare–foal pairs from days 1–7 and days 14, 21, and 28 after birth from 18:00 to 06:00 h. The suckling behaviour was recorded using a continuous recording method and suckling bouts, successful suckling bouts, and unsuccessful suckling bouts were calculated from the recordings of suckling behaviour. The terminator of the behaviours was also recorded. Behavioural data of the ‘first week’ (data from days 1–6 were averaged) and the ‘next three weeks’ (data of days 7, 14, 21, and 28 were averaged), foal weights, mare parity, and foal sex were used for statistical analysis using generalised linear mixed models with Gaussian error distribution. For the ‘first week’, negative relationships were found between suckling, suckling bouts, successful suckling bouts, several foal terminating behaviours, and foal weight gain, but no relation was found between all behaviours and foal weight gain for the ‘next three weeks’. The number of mare parity was found to have a positive relationship with the foal weight gain of the ‘first week’ and negative relationships were found between suckling, suckling bouts, successful suckling bouts, and the number of mare parity in the ‘first week’. The results of this study suggest that suckling behaviours in the first week after birth are negatively correlated with foal weight gain and that mare parity affected the results. It is also suggested that in horse reproduction systems, suckling behaviour terminated by the foal can be a negative indicator of foal growth, especially in the first week after birth.

Giraffe males have longer suckling bouts than females

Abstract In polygynous mammals, females are expected to bias maternal investment in favor of male calves. The mother should invest more in males to enhance their reproductive success in adulthood, or the males require greater investment as they are bigger and stronger than females. In this study, we used nursing duration to compare the difference in the amount of maternal investment provided by females. We compared differences according to sex of the offspring and the influence of calves’ identification by sniffing, using captive giraffes (Giraffa camelopardalis) as a model. Since a high intensity of allonursing (nursing of a nonfilial calf) was reported in giraffes, we also focused on the difference between filial and nonfilial calves. We observed 22 nursing females and 47 suckling calves in four zoological gardens in the Czech Republic from 2007 to 2011. Nursing duration was longer for male calves than for female calves and for calves sniffed by the nursing female regardless whether the calves were filial or nonfilial. We conclude that male calves are more demanding for the amount of investment received and they are more successful in this effort than female calves. Since females provided investment in the same way to filial and nonfilial calves, selection for higher demand for investment by male than by female offspring should be important for their future development. Our results also demonstrate the importance of sniffing for the identification of the suckling calf by the female.

Maternal responsiveness to suckling is modulated by time post-nursing: A behavioural and c-Fos/oxytocin immunocytochemistry study in rabbits.

Doe rabbits nurse once/day for approximately 3minutes, with circadian periodicity, inside the nest box. The amount of suckling received at each bout regulates this behaviour because reducing the litter size to four kits or less disrupts nursing circadian periodicity and increases suckling bout duration. Additionally, the likelihood that does will nurse kits at a given time of day depends on the time elapsed since the last suckling episode and the litter size nursed then. We hypothesised that the time elapsed since the last nursing would impact the number of c-Fos immunoreactive (IR) cells observed after suckling five kits and also that observed before the next nursing ("no kits"). Suckling significantly increased, relative to "no kits", the number of c-Fos-IR cells in the medial preoptic area and lateral septum but not in the bed nucleus of the stria terminalis (BNST), suprachiasmatic nucleus or ventromedial hypothalamus in does nursing at 18or 24hours after the previous bout. No effects of suckling were observed in mothers nursing at 6hours. Does given kits at 3hours post last suckling refused to nurse but, in the remaining three groups, all does nursed normally. At "no kits", more c-Fos-IR cells were seen (in all regions except the BNST) in does given kits at 24hours after the last nursing and killed 1hour later (ie, 4hours after lights on) than in those killed earlier. The percentage of oxytocinergic (OT) cells co-expressing c-Fos was not modified by nursing in the paraventricular or supraoptic nuclei but, in the latter, the largest number of total OT-IR cells occurred at 18 and 24hours post-last nursing. In conclusion, the responsiveness of particular forebrain regions involved in regulating circadian rhythms, lactation, and maternal behaviour is modulated by suckling and time of day.

Comparison of three different farrowing systems: skin lesions and behaviour of sows with special regard to nursing behaviour in a group housing system for lactating sows

While group housing (GH) is mandatory in the European Union for the greater part of pregnancy, single housing in farrowing crates (FCs) during lactation that restrict sows in most of their natural behaviour patterns is still practised on a large scale. Research is urgently needed to develop alternative farrowing systems that improve sows’ welfare. Therefore, sows in three different farrowing systems – pens with FC, loose housing (LH) pens and GH for six sows – were compared regarding the level of skin injuries and their active and resting behaviour. A skin injury score was assessed for 15 body parts of 102 sows in six batches on 3 days (days 1, 14 and 34). In total, the active and resting behaviour of 77 sows in six batches was examined on 3 days (days 18, 25 and 32) between 0700 h and 1900 h by means of a scan sampling method. The suckling behaviour and the level of cross-suckling were analysed in GH by means of direct observation in four batches during three 4-h sampling periods (days 17, 24 and 31). No significant differences were found in total skin injuries when the sows entered the systems (day 1), but GH sows showed significantly higher total skin injuries compared to FC and LH sows in the middle (day 14) and at the end (day 34) of the lactation period. A significant difference between FC and LH sows was never seen. Differences were found for the proportion of different body postures between the three systems. The odds for lying in lateral recumbency versus standing and sitting versus standing were significantly higher for FC and LH sows compared to GH sows. Additionally, sows were significantly more likely to be standing as opposed to lying in lateral recumbency as the lactation period progressed. Cross-suckling was a frequent behaviour in GH, seen in 35.0% of all successful suckling bouts. However, only an average of 0.56 piglets per successful suckling bout was observed cross-suckling, suggesting only a few piglets were engaged in cross-suckling. In conclusion, the skin injury score was only moderately increased in GH compared to FC and LH and comparable to pregnant group-housed sows, both free farrowing systems seemed to be an environmental enrichment for lactating sows and good management cannot prevent the occurrence of cross-suckling in a GH system, but can probably reduce it.

Suckling behaviour and health parameters of sows and piglets in free-farrowing pens

The aim of the present study was to investigate the effect of free-farrowing pens and farrowing crates on the health parameters and the suckling behaviour of sows and their piglets, which were housed in farrowing crates (FC; n = 127) and in free-farrowing pens (FP; n = 121). All sows were evaluated regarding their body condition, locomotion, skin lesions of the udder and developmental stages of shoulder ulcers one week ante partum and four weeks post-partum. The piglets were scored concerning skin lesions of the face and of the carpus in week one of lactation and in week four of lactation. The FC sows had a higher incidence of locomotion problems and skin lesions of the udder four weeks post-partum (p < 0.05). In addition, piglets of the FC sows showed more skin lesions of the face and had more skin lesions of the carpus in week one of lactation and in week four of lactation, respectively (p < 0.05). For all piglets of both housing systems skin lesions of the face decreased during lactation, whereas skin lesions of the carpus increased (p < 0.05). With regard to the suckling behaviour, video observations of twenty-four sows (FP: n = 12; FC: n = 12) and their litters on lactation day four were analysed concerning the suckling duration, suckling frequency and suckling termination. For each housing system, six sows with litters with a low level of facial lesions and six sows with litters with a high level of facial lesions were chosen to investigate the influence of the suckling behaviour on the facial lesions of the piglets. The suckling duration per suckling bout was longer in the FP systems than in the FC systems (FP: 6.81 min vs. FC: 5.95 min; p < 0.05). Moreover, sows with litters with a low level of facial lesions terminated suckling less frequently (p < 0.05). In conclusion, keeping sows in free-farrowing pens can have a positive effect on the sows’ health by reducing the incidence of locomotion problems and skin lesions of the udder, as well as skin lesions of the face and skin lesions of the carpus of the piglets. Furthermore, the results show that the housing system has an influence on suckling duration and the incidence of skin lesions of the face of the piglets has an influence on sows’ terminations of suckling.

Suckling and allosuckling behavior in wild giraffe (Giraffa camelopardalis tippelskirchi)

Allosuckling has been reported in many mammalian species. In giraffe, allosuckling has been observed in captivity, and the milk theft hypothesis with reciprocity is regarded as the likeliest explanation for this behavior. However, reports of such behavior in the wild remain sparse to non-existent. Here, we studied the suckling and allosuckling behaviors of three nursing giraffe and their offspring (two calves and one juvenile) for 32 days in the Katavi National Park, Tanzania. In total, we observed 56 suckling bouts, 96 suckling attempts, 5 allosuckling bouts, and 71 allosuckling attempts. We observed that the female decided when to nurse the offspring, as reported in previous studies; however, the suckling bouts of calves were terminated mainly by other individuals. On the other hand, all suckling bouts of juvenile were terminated by the female. The milk theft hypothesis was supported since (1) the allosuckler always joined a suckling pair and never succeeded when approaching a female by itself, (2) the female apparently did not notice the non-filial offspring positioned behind the filial offspring, and (3) the female showed active signs of rejection when she noticed the allosuckler. In addition, we found that juvenile close to weaning showed the highest rate of allosuckling interactions. Therefore, we assume that the presence of a weaning individual might drive the occurrence of allosuckling in giraffe in the wild.

Validation of accelerometer use to measure suckling behaviour in Northern Australian beef calves

Knowledge of suckling behaviour in beef calves is important for understanding the health and wellbeing of both cows and calves. The present study was conducted to explore the use of tri-axial accelerometers to identify suckling bouts and suckling duration per bout in beef calves under free-range conditions. Three experiments were conducted: Experiment 1 was conducted to develop a model to characterise suckling in calves; Experiments 2 and 3 were conducted to apply the model when cattle were managed in pastoral paddock conditions. One Holstein Friesian and one Droughtmaster cow-calf pair were used in Experiment 1 for 2 days. The tri-axial accelerometer was fitted to a neck collar of the Droughtmaster calf and at the bottom and the right side of a halter on a Holstein Friesian calf on consecutive days. The initial model was developed using data collected from one calf for one day only to classify accelerometer data into suckling and non-suckling periods. In Experiment 2, 24 Belmont Red calves with accelerometers attached on the right side of the halters were visually observed for 10 days. The model was applied to raw data obtained through use of the accelerometers and the model could be used to successfully identify 98.8% of suckling bouts when compared with visually recorded behavioural data. The average suckling duration per bout recorded by accelerometers was 9.72 ± 0.20 min, whereas visually it was 9.32 ± 0.19 min. In Experiment 3, 20 Brahman calves fitted with accelerometers were visually observed for 6 h for 3 consecutive days. The model could be used to identify 95% of suckling bouts from the accelerometer data, corresponding to total number of suckling bouts observed visually. The average suckling duration per bout recorded by accelerometers was 13.69 ± 1.82 min, while with visual observations was 12.23 ± 1.77 min. The results indicate that accelerometers are a very effective tool to record suckling behaviour in beef calves in pastoral paddock conditions.