1. Parental Care Christel Moons

2. What is parental care? Parental care (or parental investment) = Any behavior towards offspring that increases the chances of the offspring’s survival at the cost of the parent’s ability to invest in other offspring

3. Advantage of parental care? Offspring: survival Parent: evolutionary advantage – Contributes to reproductive fitness – Fitness = The relative ability of an organism to survive and leave offspring that themselves survive and leave offspring

4. Disadvantage of parental care? Expensive to provide parental care – Staying close to the young (  new mating) – At the expense of own survival rates Foraging for food that mainly goes to offspring Presence of young attracts predators Hypothesis by David Lack: (trade-off) There is a cost of reproduction that forms some sort of limit on how much an animal can do to provide care to its offspring

5. The imbalance between the sexes Animal kingdom: Females provide most or all of parental care Resulting from evolutionary imbalance –Females invest more in conception, gestation, parturition –Males provide ‘cheap’ sperm, take no part in gestation, parturition –Exceptions to the rule: e.g. Stickleback, Sea Horse

6. Maternal care in mammals Altricial mammals – Deaf, blind – Deficient in motor control and temperature regulation – Need: Nursing Warm nest Retrieved into the nest – Parental care: Lick offspring for defecation/urination; defensive

7. Characteristics of newborn mammals (cont.) Precocial mammals (Ungulates) – More motory and sensory mature (large groups, migrating in search for food) – Need: Fast drying after birth Nursing – Parental care: No nest building Encouraging first attempts at standing/walking and nursing Selective, individual bond with foal (recognition in herd)

8. Maternal care in horses

9. First mare-foal interaction Gestation: 315-365 days (average=340) Parturition = act of giving birth After parturition: – Mare licks fetal membranes – = Process to become familiar rather than cleaning – Olfactory cues !!! – Primary socialization established within 2 hrs. – Separation  extreme anxiety + disorientation by the foal

10. First mare-foal interaction (cont.) Foal develops motor/auditory/tactile skills fast – Foal initially follows any large object – Gradually learns ‘correct object’ First nursing attempt after standing: – Standing: within 60, up to 120 minutes after birth –Fillies vs. Colts – Nursing: 30 – 120 minutes after birth ‘air sucking’ Nursing position = reverse parallel Bunting

11. Indicators of maternal care 1. Proximity – Distance between mare and foal – On pasture < 5 m on day 1 – Due to foal behavior, even when lying down – Very little physical contact – Recumbency response: “when her foal lies down, the mare stops engaging in any other activity and stays near her young, by instinct on alert for predators, even though there may be no such dangers anywhere near” – Trends with age

12. Indicators of maternal care (cont.) 2. Nursing – Definitions (research-based): 1979: The time a foal first nuzzled the mare’s udder for 3 seconds until the final time the foal removed its head from the medial side of the mare’s hind limb 1980-81: Start of a nursing bout was recorded when the foal actually sucked for the first time 1983: A period of nursing activity delimited by intervals of non-nursing activity lasting for  27 secs

13. Indicators of maternal care (cont.) – Definitions (cont.): 1992: Including pre-nurse nuzzling, sucking, intra- bout pauses and intra-bout nuzzling 1994: Including pre-suck nuzzle, pre-suck pause, suck, intra-suck nuzzle and intra-suck pause

14. Indicators of maternal care (cont.) Functions of nursing: Nourishment Initial passive transfer of immunity (Colostrum) Comfort Behavior

15. Indicators of maternal care (cont.) Nursing Behavior – Initiation of nursing : By mare By foal –Crossing the bow

16. Indicators of maternal care (cont.) Nursing Behavior – Nursing bout frequency and duration Frequency (per hour) Belgian draft horses 9 Draft + mule foals 14 Welsh ponies 4 Duration: 78 – 84 seconds

17. Indicators of maternal care (cont.) Nursing bout termination – Constant individual differences between foals – Mares < Foal – Termination by foal: Remove head from udder Walk away – Termination by mare (Welsh ponies): Walk away Kick at abdomen Lift hind limb to obstruct nursing Direct aggression against foal

18. Indicators of maternal care (cont.) 3. Aggression – Rare during first month; nursing related – Different forms: Laying back of ears Bite threat Bite Kick threat Kick Squeal Bunt Tail swish

19. Indicators of maternal care (cont.) – Response from foal No discernable response Short pause in nursing Aggressing back at the mare

20. Indicators of maternal care (cont.) 4. Other interactions Mutual grooming = Reciprocal coat care in which the partners nuzzle and chew on one another’s coat Fillies (  ) groom about twice as much as colts (  ) do

21. Indicators of maternal care (cont.) 4. Other interactions Play 3 major types of play: general motor, interactive, and object manipulation In stall: foal explores environment by mouthing parts of stall, mare’s tail/ear/halter On pasture: Galloping away from the mare in what appears to be thrill-seaking behavior