View source for Breeding In-hand - Donkey

[[Image:In-hand breeding donkey 3.jpg|right|thumb|200px|<small><center>In-hand mating to a mare. Note the flehmen response (Image courtesy of    [http://drupal.thedonkeysanctuary.org.uk The Donkey Sanctuary])</center></small>]]
The '''space and freedom of interaction between the jack and the jenny''' seems to be a key factor in sexual stimulation. The time to first mount increases if the jenny is restrained (Henry ''et al'', 1991; Gastal ''et al'' ,1996). It is recommended that enough space be provided during in-hand mating of a jenny for the retreating behaviour to take place.

The alternating slow/fast approach and retreat to and from the jenny is a unique behaviour in jacks (Henry ''et al'', 1998; Lodi ''et al'', 1994). The number of retreats is generally higher for the first ejaculation than for successive ejaculations (Gastal ''et al'', 1996). The presence of other receptive jennies may enhance the sexual stimulation, whereas the presence of other jacks may distract or inhibit sexual activity given the territorial nature of this species (Kreuchauf, 1984). The time from  introduction to a female to mounting and ejaculation varies from 6 to 32 minutes according to studies (Tibary, 2006).

During the pre-copulatory and copulatory phases, jacks exhibit a sequence of behaviour including '''nose-to-nose contact, flehmen
responses, mounting without erection, partial and total exposure of the penis, sniffing and biting specific areas of the female’s body, lip clapping and slow/quick retreats with vocalization'''. These behavioural parameters show significant individual variations.

The frequency of flehmen response (usually five to eight times) is generally higher than in stallions and does not seem to be affected by rank of ejaculation. The initial reaction of the jack in the breeding shed is vocalization, followed by one or several mounts without erection. The first mount is performed without erection in 70% of the cases. The number of mounts without erection varies from one study to another and is probably affected by training and handling differences (Tibary, 2006).

Frequent partial exposure of the penis during the pre-copulatory phase is common in jacks (Kreuchauf, 1984; Henry ''et al'', 1998; Henry ''et al'', 1991). Total exposure of the penis is generally followed by erection (Gastal ''et al'', 1996). The first erection does not always result in ejaculation. Jacks may show several erections and masturbation before mounting and ejaculation.
The mean time from first contact with the jenny until the first erection varies between 10 and 15 minutes. Depending on  individual animals, stallions display four to eight pelvic copulatory movements before ejaculation.

A '''seasonal effect''' on libido has been reported by some authors with decreased latency to first mount, first erection and  ejaculation during spring and summer (the breeding season). This seasonal effect may vary from one region to another (Tibary, 2006).

It is the experience of the authors ( Tibary, A., Sghiri, A. & Bakkoury, M.) that breeding jacks to mares is more challenging with often increased latency to erection, mount and ejaculation.

In pasture breeding systems, lack of conditioning of jacks to breed mares may result in lower reproductive efficiency. It has been suggested that jacks destined for mule production should be raised with horse fillies after weaning, and prevented from any contact with jennies until they are adult (Henry ''et al'', 1998; Henry, 2001).

In pasture, pre-copulatory, copulatory and post-copulatory behaviour for stallions breeding with mares is similar to that for stallions breeding with jennies (Lodi ''et al'', 1994). The interaction between mares and stallions is reportedly shorter in duration but more frequent. Also, jacks seem to elicit signs of oestrus from mares with less intensity. In one study the  percentage of oestrous mares exhibiting signs towards a jack varied from 28 to 43% whereas 93% exhibited sexual behaviour to stallions (Lodi et al, 1994; Henry, 2001).

In a stud farm situation, we have observed latency to erection and ejaculation of up to 120 minutes when breeding hobbled oestrous mares (Tibary et al, 2005). In addition to behavioural differences that may affect fertility results, size discrepancy may be another constraint in stallion/ mare breeding.