Camelid Mating - Anatomy & Physiology

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Male

Rutting Behaviour

Agressiveness

  • Increasing aggressive towards other males, and sometimes even towards people, during the breeding season.
  • Males that are confined show increased pacing and anxiety and may make several attempts to break out.
  • If they are kept with females they spend most of their time guarding the herd and surveying it for the presence of other strange males.
  • Because of this continuous stress there is a reduction in food intake and frequent diarrhoea resulting in a loss in weight - sometimes up to 35%.

Soft Palate Ejection

  • Exteriorisation of the soft palate, known as the dulah
  • The protrusion of the soft palate occurs all day long at intervals of 15 - 30 minutes and is accompanied by loud gurgling and roaring sounds.
  • The protrusions become more frequent with increased excitement such as the presence of other males and females.
  • During copulation the soft palate ejection may be replaced by grinding of the teeth and frothing at the mouth.
    • This frothing is generally attributed to increased secretion of the salivary glands and the frequent exteriorisation of the soft palate.

Marking

This is one of the main sexual behaviours exhibited during the breeding season. It generally takes on two forms, urine spraying and smudging of poll gland secretions.

Urine Spraying
  • Increased in the presence of another male or when females are passing nearby.
  • Crouched urination posture and urine is ejected towards the back in small quantities and spread over the croup of the animal and surrounding areas with regular tail beating.
  • The tail is held under the prepucial opening for a few seconds and soaked with a stream of urine which then is sprayed by 4 to 5 beats of the tail.
Smudging
  • Used to disseminate the secretions of the poll gland.
    • The secretions are light brown/amber in colour when first excreted but become tarry and dark after a few minutes.
  • It can easily be seen dribbling down the neck of the male and has a very strong smell.
  • The area corresponding to the poll glands becomes large and darkened due to this increased activity.
  • These secretions contain androgens and pheromones that are used to mark a territory.

Female Seeking

During the breeding season males continue to seek receptive females.

  • Sniff the perineum and flank of the females and frequently display a flehmen response.
  • Males that roam freely with females will often chase them and force them to sit down by putting pressure on the neck, even if they are not receptive.

Female

Puberty

  • Sexually active at 2 - 3 years of age but usually they are not bred until they are 4 years old.
  • Several factors that can influence the age of the onset of puberty, such as nutrition, season of birth and breed.
    • The most important factors being the nutrition and adequate growth, as these influence the onset of ovarian activity and chances of conceiving and carrying the pregnancy to term.
    • If females are bred before they reach 70% of their adult body weight they run a greater risk of abortion.

Seasonality

  • Seasonal breeders, with a relatively short breeding season.
  • Outside of the breeding season mating activity ceases and the ovaries are inactive or only have a few, small follicles.
  • Breed at a time of low climatic temperature, rain and better grazing conditions.

Endocrinology of Seasonality

  • Plasma levels of oestradiol 17β very considerably from one month to another but there does not seem to be any association between the level of this hormone and breeding activity.
  • Concentrations of LH are higher during the breeding season than during the non-breeding season.
    • During the breeding season the pituitary gland is more sensitive to and releases more LH in response to Gonadotrophin Releasing Hormone (GnRH) release from the hypothalamus.

Oestrous Behaviour

The proportion of females displaying strong oestrus behaviour is usually small and not all the females will show all these signs, despite the presence of a mature follicle. Also, receptivity to the male can be displayed by females with no follicles in the ovaries and for up to 7 days after ovulation or when pregnant and progesterone levels are high. Oestrous behaviour therefore cannot be used reliably to decide the timing of breeding.

  • Mounting other females
  • Restlessness
  • Swelling of the vulva
  • Straddling the hind legs and urinating
  • Vaginal mucus discharge
  • Receptivity to the male
  • lasts on average 4 - 6 days, but can vary from 1 - 21 days.

Copulation

In the UK, the aim is to mate females at around 1 year of age. As long as they are fully grown and well-nourished this results in acceptible levels of fertility and health in the mother and cria. Once calved, the female will become receptive to the male again in 2-3 weeks. The female should be able to conceive again if mated at this time.


  • Mating is carried out with the female sitting in sternal recumbency and the male squatting behind her with his hind legs flexed and his forelegs extended on either side of the female.
  • The duration of copulation can vary and tends to decrease as the weather becomes warmer.

Erection

  • Erection is only achieved after the female is mounted in a sitting position and the penis is not fully extended until after intromission is complete.

Ejaculation

Paddock Mating

  • Male is left to run with the females
  • Requires little human intervention
  • Precise calving dates will not be known.

Hand or Pen Mating

  • Supervised mating where the female is put into a pen with the male while mating takes place and then returned to the paddock without males.
  • Timing of mating is known.
  • Sire of cria is known.
  • Valuable males do not waste energy inseminating the same female repeatedly, thus can be used to impregnate more females.
  • Much time can be wasted if receptive but non-fertile females are presented for mating.
    • When the male is with a herd of females, he can determine the best time for mating and immediately mate the most receptive females.

Stud Services

  • One stud male can serve up to 40-60 females per year.
  • Stud farms are common.
    • Have stud males as a major source of income, selling services to breeders without a stud male.
    • May involve transporting females to the stud farm, or in some cases leasing the male to inseminate many females.

The Mating Process

  • Male will approach with tail held high, head and neck extended towards the female.
  • Female should tolerate the approaching male.
  • The male will 'orgle', the unique gutteral call of mating.
  • Female will 'kush' (lie down) immediately or when he mounts her if she is receptive.
  • Male positions himself tightly over her hind-quarters, with his forelimbs clasped around her chest.
  • Copulation may last ~30 minutes.
    • Sometimes the female lies down with her head outstretched, and occasionally will lie on one side.
    • Male may dismount, reposition himself, and begin again. Occasionally he will get up and move away before recommencing.

Rejection

  • Typically the female spits vigorously at the male to discourage his approach.
  • Experienced stud males may be insistent, and if the female has enough space she will run from him.
    • Receptive females may run initially, then allow themselves to be caught.
  • Males are uninterested in non-receptive females.
    • May sniff females of the herd in turn and ignore the non-receptive ones.
  • Triggered by high progesterone levels in the female.
    • With a persistent corpus luteum, she will continue to reject the male even if she is not pregnant.

Timing of Mating

Timing mating so that pregnancy is most likely to result is important to avoid wasting time, effort, expense, stud male energy and sperm supply.

  • Female is presented to the male.
  • If she is not pregnant, she will be expected to 'kush' to accept mating.
  • Following mating she should reject the male by running or spitting.
  • Unless she had an immature follicle at mating, thus did not ovulate, this process will happen for at least 5-6 days.
  • As immature follicles mature, she may accept further mating in 2-3 days at which time ovulation may occur.
  • If the follicle present at the time of mating was too mature, it will not have ovulated but will still have undergone luteinization.
  • If ovulation took place, the normal progesterone-dominated luteal phase of 10-12 days follows.
  • If there is no pregnancy, then a new follicular wave proceeds and the female becomes receptive again under the influence of oestrogen.
  • Tease the female 3-6 days after a mating.
  • If she rejects, tease again at 10-12 days after the original mating in case there was ovulation but no pregnancy.