132

Observations on the birth of a nyala TrageZaphus angasii

at Marwell Zoo JEFFREY WEBB Marwell Zoological Park, Winchester, Great Britain

On 30 November 1971 Marwell Zoo received a group of two 3 and seven 9 nyala Tragelaphiis argasii. They were in good condition on arrival, suffering only a few crate sores, and despite the noise and disturbance of nearby construction work settled down well in their new enclosure, to the extent that the 99 were soon tame enough for hand-feeding. Their quarters consist of a timbered house with a main hall, two calf stalls and a food store, and an adjoining outdoor, concrete-floored enclosure. The daily diet is a mixture of flake maize, bran, dairy nuts, oats, sugar beet pulp, high magnesium nuts, apples, carrots and cabbages, all mixed together with a little cod liver oil. Hay is always available and in summer the fruit is replaced by fresh hazel, hawthorn, beech, sycamore or elm leaves.

Breeding behaviour was first observed in early December but was soon followed by the accidental death of the adult 8, the most nervous of the group. A tractor driven too close to the enclosure caused him to panic and run headlong into the fence, severely cutting himself about the nose and jaw. He died later under sedation.

It was not until about three weeks before the first birth in August that the 99 began to show signs of pregnancy, and at about this time the younger 8 was also seen mating. The first calf, a 9, was lorn on I August 1972 and was discovered at 1830 hours lying on the floor of the house, with the mother in attendance. It was about four hours old and quite dry. The 9 was found to have no milk but it was decided to leave the two together for the night. At 0730 the next morning we found the calf lying alone on its side and mori- bund. It was transferred to a warmer room but died almost immediately. Post-mortem revealed lung congestion.

The second ? calf was born on 3 August. It was discovered at 0730 hours, sitting in the main hall area. Barely two hours old, it was still very shaky, with forelegs splayed, and it had not been properly

B R E E D I N G

cleaned. Female and calf were separated into a stall with a deep bed of straw and an infra-red heater. The 9 had plenty of milk and although she seemed a little restless and disturbed at being separated from the group she managed to eat a few dairy nuts. The calf was first seen to suckle briefly at 0910 hours and later in the day was observed suckling well. It trembled a little as if cold. The next day the 9 was more relaxed and ate some oak leaves, while the calf slept for most of the time. On Day 3 as the weather was fme the two were released with the rest of the herd. The other 99 took great interest in the calf, licking it all over, while the 8, shy at first, began to display before the 99 as if stimulated by its presence. The following day he seemed noticeably more dominant and protective towards his harem and appeared anxious to see mother and calf again.

We were able to observe and record the third birth on 8 August. 1130: One of the ?? appeared to be acting

strangely, standing apart with tail raised. She did not look pregnant.

1445 : Her strange behaviour persisted, now with periodic contractions.

1625: She was discovered in the main hall area with another, heavily pregnant 0 beside her cleaning her hindquarters.

163 5 : After several contractions, in both lying and standing positions. two hooves appeared. The other 9 proceeded to clean them.

1655: With much straining and apparent difficulty the head appeared and the second 9, now acting as midwife, began to butt her in the side as if to make the contractions more regular and help the birth. Another of the ?? entered.

1710: The calf was dropped from a standing position. A third ?joined the ‘midwife’ and all three proceeded to clean it. It was a 9 and much larger than its predecessor.

B R E E D I N G I 3 3

Throughout the previous 45 minutes the mother had constantly lain down and risen again, straining more in the lying position. During this time the $. stood outside the door and only entered three times to look around.

1730: Mother and calf were put into a heated stall.

I 757: The calf stood for the first time. 1803 : The calf began to suckle. 1901 : The discharged the afterbirth and ate it.

1945 : Mother and calf seemed relaxed and ready

gave birth successfully to yet another 9 calf. Mothers and calves were all put together with the rest of tlic herd without trouble. By the end of August all but the first-born calfwere doing well. The latter seemed too small but as it suckled well and ate hay along with the rest it can only be assumed that it is a slow starter.

to settle for the night. The following day another of the

Manuscript submitted 16 April 1973

Breeding behaviour of Sable antelope

in captivity Hippotragus niger

HELMUT K. BUECHNER, HERBERT K. STROMAN &WILLIAM A . XANTEN

National Zoological Park, Snrithsonian Institution, Washington, DC zooog, USA

To our knowledge, there are no published accounts of the complete reproductive behaviour of the Sable antelope Hippotragus niger. Courtship behaviour has been described by Huth (4) at the Frankfurt and Hanover zoos, and by Estes & Estes (3) under natural conditions in Kenya and Angola. Six gestation records are given by Dittrich (2). who notes that zoo observers often fail to see African antelope copulating because of the short duration of oestrus ( < 36 hours) and the brief period of mating - a few minutes or even seconds. In our experience the Sable’s sensitivity to disturbance is an added factor.

The Sable at the National Zoo can be seen by the public from the base of a moderate slope, and normally not from an upper path or around the stall. The niain enclosure (1858 ma) is connected to a smaller paddock of 994 ms and also, at the opposite side of the duplex stall, to another, larger enclosure (2044 ml). These neighbouring enclosures are off public view. The nature of the terrain, variety of trees, shrubs and herbaceous vegetation, along with large, strategically placed logs, provide considerable diversity within the enclosures. In view of the Sable’s exceptional

K

alertness and pugnacity, the arrangement of the enclosures is well suited to the exhibition and management of these animals.

The following observations were inade by Buechner on 13-14 June 1972 from the seclusion of the stall. Small windows ( 5 x 15 cm) in two doors enabled him to see without disturbing the animals.

H I S T O R Y

Our herd of Sable currently stands at five (I/I adults, o/r three-year-olds, I/I two-year-olds). It began with 112 animals, estimated to be 1 5 2 years of age, which were received from Africa on 5 September 1968. The first two offspring, a 9 born 23 and a 3 born 24 May 1970, were transferred as yearlings, the 9 being traded for another of comparable age from the Baltimore Zoo with the intention of introducing new genetic stock. A 6 was born 28 May 1971 and a 9 on I7 July of that year. In I972 a calf died 21 days after birth, followed by the death of the mother on 12 May; another 9, born 22 April, died on 9 March 1973. The o6pring of the conception observed on 13 June 1972 was born