LPM 222: Diversified poultry production and current concepts in poultry management and marketing [Livestock Production Management (Regional Interest)] (1+1)

EMU BREEDER MANAGEMENT

Age at sexual maturity

• Generally the hens are mature at two years of age, although some birds may begin laying eggs at as young as 18 months.
• Males are generally sexually mature at 2 ½ to 3 years of age. If the eggs are infertile during early part of the breeding season, this is usually caused by the infertility of the cock.

Sex separate rearing

• Juvenile hens and cocks should be reared separately from 1 year of age to sexual maturity.
• Mature hens and cocks should be separated after the breeding season. This will allow the birds to be more rested, and they will begin egg production more readily when placed together for the breeding season in September.

Mating behaviour

• During the mating season, females become physically more attractive. Unlike many other poultry species, female emu initiates courtship. The female strides around confidently, often circling the male, and pulls its neck back while puffing out her feathers and crying out a low, mono syllabic sound that has been compared to human drums. This calling can be heard by males that are even more than 50 metres (160 ft) away and when the male's attention has been gained, the female circle in a radius of 10 to 40 m. As the female circles its prospective mate, it continues to look towards him by turning its neck, while keeping its rump facing him.
• During this time, the female's cervical air sac may remain inflated as it calls out. Females are more aggressive than males during the courting period, often fighting one another for access to mates. If a male is interested, he will stretch his neck and erect his feathers and bend over and peck at the ground. He will then sidle up to the female, swaying his body and neck from side to side, and rubbing his breast against his partner's rump.
• The female would accept by sitting down and raising her rump. The pair mates every second or third day.

Emu semen

• Naturally mated female emus store spermatozoa in the tubules of the oviduct and release them over a period of time, termed the “fertile period”, during which a maximum of 6 eggs can be fertilized.
• Volume of ejaculate in Emu is ranging from 0.4 to 1.2 ml and each ejaculate contains about 1.2 to 3.5 × 10⁹ spermatozoa. Semen collection and artificial insemination was successful in emu so that the cost of male maintenance could be minimized. Its implementation needs skill.

Sex ratio

• In pen mating sex ratio of male to female is kept at 1:1 (pairs) or 1:2 (trios). In case of pen mating, pairing should be done based on the compatibility. In group mating, sex ratio of 1:2 to 1:3 can safely be followed. At the peak reproductive age even sex ratio of 1:4 gives satisfactory fertility.

Changes in emus during breeding season

A number of changes take place leading up to the beginning of the breeding season:

• The emus do not have a dramatic mating dance like ostriches do, but the male does throw feathers and grass over his back, trying to catch a female’s attention. He also prepares the nesting site, and shows her where he wants her to lay her eggs.
• Females start drumming much more as breeding season approaches, and continue throughout the season. At the end of the season they do not drum a lot anymore.
• Males grunt more as the season approaches.
• The blue skin on the neck of the emus (male and female) becomes more pronounced in most birds.
• Aggression among younger females becomes more pronounced.
• Males become overly friendly with anything moving around on two legs – including humans.
• Males and females strut around and blow out the throat sac, which becomes large and pronounced.
• As breeding season approaches, the stools of the females usually become green, from the coloring of the eggs. Not all birds have green stools, so this should not be used as an indicator of if the hen is laying, but it can be used as a signal to the imminent arrival of the first eggs.
• Once breeding season has begun and most birds are laying, fighting becomes minimal. Usually by this time, most birds have paired off, and have happily settled into a routine.

Nesting behaviour

• Nesting takes place in winter. Males lose their appetite and construct a rough nest in a semi-sheltered hollow on the ground from bark, grass, sticks, leaves and few feathers in a shallow depression in the ground. The nest consists of a platform of grass on the ground, about 10 cm thick and 1 to 2m in diameter and more spherical to provide maximum insulation.

Nests

• Males generally choose a nesting spot, but to encourage the use of the shelter area to build nests clean hay may be placed in the shelter. The use of egg shells can also encourage the beginning ofbreeding, and the laying in the correct place.
• It might be necessary to erect some type of shelter over the nest to protect the eggs. If, however the eggs are to be collected for artificial incubation, this is not a problem.

Fig.9.22. Emu nest

Egg production

• Production begins in October and continues up to March.
• The time of egg laying is around 5.30 to 7 PM in the evening. Normally a hen lays about 15 eggs during first year cycle in subsequent years the egg production increases till it can reach about 30 to 40 eggs. On an average a hen lays 25 eggs per year.
• The productive life is approximately 16 years. Egg weighs about 450 to 650 g with an average egg weight of 550 g in a year. Egg appears like a tough marble with emerald green colour. The intensity of colour varies from light, medium to dark green.
• The surface varies from rough to smooth. Majority of eggs are medium green with rough surface.

Egg collection

• Eggs can be collected twice daily to avoid damage in the pen if artificial incubation is followed.
• Reproductively active cocks can be extremely protective and aggressive.
• Caution should be taken when entering their breeding areas.
• Aggressive cocks can be fed and penned in a catch or holding pen while eggs are collected.

Egg cleaning and storage

• If eggs are soiled, clean with sand paper and mop up with cotton.
• Store the eggs in a cooler room providing 60ºF. Never store eggs for more than 10 days to ensure better hatchability.
• Eggs stored at room temperature can be set every 3 to 4 days for good hatchability.

Feeding

• Breeder diet fortified with minerals and vitamins is provided well in advance, 4 to 6 weeks prior to breeding to ensure better fertility and hatchability.
• During the breeding season emus eat much less, and the males will often stop eating completely, especially if they are broody. Normally adult bird consumes 1 kg feed/day but during breeding season feed intake will be drastically reduced hence intake of nutrients must be ensured.
• It is therefore imperative to fortify the nutrients especially vitamins, minerals and protein for the breeding birds. Vitamin and mineral supplements to the feed or water can also be made.
• Cracked corn can be added to their diet when temperatures drop to extremes, providing the birds with extra energy.
• Calcium from limestone or another source should be left in a separate feeder, to be utilised by the females. This should not be mixed into the feed, as overfeeding of calcium is harmful to males. When it is placed separately, each bird will utilise as much as they need.