Key Technical Points and Rearing Management Methods for Laying Ducks
As consumer demand for laying ducks grows, China's laying duck market has become larger and more developed, and raising laying ducks has become the primary choice for livestock farmers or laid-off workers.
Physiological characteristics of laying ducks
1. Ducks and other poultry do not differ greatly in reproductive physiology: continuous ovulation, internal fertilization, and embryonic development outside the body. Because domestic ducks (except Muscovy ducks) have no broodiness (incubation behavior), artificial incubation is necessary.
2. In the female duck, only the left ovary and oviduct develop to maturity, while the right side has degenerated. The function of the left ovary is to ovulate and form eggs, and on the right side there is also a very poorly developed male gland. If there is an appropriate number of drakes in the flock, the male hormones secreted by the drakes will inhibit the development of the right-side male gland in the female duck, thereby inducing the ovary to ovulate more and lay more eggs. When there are no drakes or too few drakes in the flock, there is not enough male hormone to inhibit the development of the female duck's male gland. Under certain circumstances, the right-side male gland in an individual robust female duck will develop, producing large amounts of male hormone, which in turn inhibits the normal function of the left ovary. As a result, the individual female duck stops laying eggs and shows a sex reversal phenomenon, with feathers gradually becoming glossy and beautiful, closely resembling a drake.
3. The sexual desire of female ducks is much stronger than that of chickens, geese, quails, pigeons and other poultry, and this is relatively obvious in flocks that include drakes. When approaching the start of laying and during the peak laying period, female ducks often follow drakes in small groups of three to five, or float quietly on the water waiting for drakes. Egg laying mostly occurs between 4:00 and 9:00 in the early morning.
4. Dominant drakes have stronger sexual activity and a higher mating success rate, and their offspring also have higher reproductive capacity: the fertilization rate is 16.8% higher than that of lower-status drakes, the egg production is 17.5% higher, and the hatchability is 5.9% higher. Lower-status female ducks are more willing to accept mating by drakes than higher-status ones; their breeding egg fertilization rate is 18.8% higher than that of higher-status ducks, the hatching rate is 29.2% higher, and the egg production of their offspring is 31.2% higher. Full use should be made of dominant drakes and lower-status female ducks to improve duck reproductive capacity. Whether drake or female duck, mating behavior declines with age; observations show that for every 100 days a drake ages, the number of matings can decrease by 7.6 to 8.2 times, and for a female duck by 1 to 1.4 times. Therefore, young drakes should be fully utilized, old ducks culled, and the flock constantly renewed to maintain good reproductive capacity and breeding value. Within a day, mating behavior is more frequent in the evening: 15% in the morning and 85% in the afternoon, with the highest mating frequency in the 2 to 3 hours before lights out. Litter flooring is a safe mating site; 80% to 90% of mating behavior occurs on litter flooring, so flat rearing on litter flooring or mixed rearing helps improve the fertilization rate of breeding eggs.
5. Both drakes and female ducks show mate preference, preferring to mate with familiar individuals. If a new drake is placed into a flock that has already established a pecking order, the female ducks will refuse to mate, affecting the fertilization rate of breeding eggs. Fighting among drakes over mating will cause new conflicts, and the losers may be injured or killed, or may enter a physiologically castrated state and lose the ability to compete for mating. During the breeding season, the flock should be observed frequently, and drakes with no breeding ability should be replaced promptly.
Factors affecting egg laying in laying ducks
Breed factors
Breed is the prerequisite for achieving high yield. The level of egg production rate, the length of the laying cycle, the strength of laying persistence, and egg size are all closely related to breed. If a superior breed is chosen for rearing, egg production can increase by several tens of percent or even double, and economic returns will rise accordingly. How to choose a high-yielding breed suitable for local rearing according to one's own rearing conditions and management techniques is the key factor determining success or failure.
Nutritional factors
After entering the laying period, laying ducks have higher requirements for nutrients than at any previous stage. In addition to nutrients needed to maintain life activities, they also need large amounts of various nutrients required for egg production. Nutrients such as energy, protein and calcium must be supplied adequately. Otherwise, the egg production rate will be affected.
To achieve a sustained high-yield level, besides breed being an innate factor, whether the nutrients in the diet are comprehensive and balanced and whether the quantity can meet requirements are essential conditions for maintaining high and stable production.
Environmental factors
Environmental factors are relatively complex, and the factors with the greatest impact on egg laying are light and temperature.
Health factors
Without a healthy body, high yield is impossible. Therefore, during the stage of raising young ducks, prevention of major infectious diseases must be done well. After entering the laying period, environmental sanitation and rearing management should be improved, disease resistance increased, and disease occurrence minimized, so as to maintain high and stable production.
Digestive and behavioral characteristics of laying ducks
Laying ducks have no teeth and a wide bill, making them suitable for eating granular and blocky food, and they eat quickly. Their salivary glands are not well developed, so they often drink water while eating to moisten the food and make it easier to swallow. When swallowing, ducks raise their heads and stretch their necks, using gravity and the negative pressure produced by the esophagus to swallow food and water. The duck tongue is extremely sensitive to water temperature and does not like water warmer than body temperature, but is not afraid of cold water.
Ducks have relatively poor digestive function and cannot tolerate high-fiber feed. The duck digestive tract is relatively short, and emptying takes 4 hours. Ducks have the habit of eating at night.
Laying ducks have a large feed intake and a good appetite. Whether in confinement or grazing management, laying ducks (especially high-yielding ducks) are the most diligent in foraging. They wake early in the morning, forage all around after leaving the house, forage everywhere while grazing, are the first to respond when feed is given, and eagerly compete for food. In the afternoon when brought back from grazing or returning to the house, although already very full, they still want to eat, always walking at the back and leaving the grazing area reluctantly.
Laying ducks have vigorous metabolism and high feed requirements. Because of continuous egg laying, they consume especially large amounts of nutrients. For example, if one egg is laid per day and the egg weight is calculated at 65 grams, then 8.75 grams of crude protein are needed (calculated at 13.5% crude protein in the whole egg) and 9.43 grams of crude fat (calculated at 14.5% crude fat in the whole egg). In addition, large amounts of minerals and various vitamins are needed. If the nutrients in the feed are not comprehensive or certain elements are lacking, egg production will decline, such as fewer eggs, delayed laying time, and rough eggshells.
Feed formulas for laying ducks
Nutrition should be appropriate. When preparing laying duck diets, the appropriate nutrient concentration of the compound feed should be determined according to the duck's age stage and feed intake.
The reference formula is: ducklings (1 week to 8 weeks): corn 58.7%, soybean meal 26%, rapeseed meal or cottonseed meal 7%, limestone powder 4% (bone meal or shell powder may also be used), special premix No. 6 4%, salt 0.3%. For ducklings in the first week, it is recommended to feed only complete pellet feed.
Growing ducks (8 weeks to start of laying): corn 64%, soybean meal 16%, rapeseed meal or cottonseed meal 6%, limestone powder 9.7% (bone meal or shell powder may also be used), special premix No. 6 4%, salt 0.3%, Jinsaiwei as appropriate.
Laying-period ducks: corn 51%, soybean meal 22%, rapeseed meal or cottonseed meal 3%, wheat middlings 10%, limestone powder 9.7% (bone meal or shell powder may also be used), special premix No. 6 4%, salt 0.3%.
It can be said that as long as farmers understand the physiological and reproductive characteristics of laying ducks, as well as the conditions for their egg laying, they need not worry about failing to raise high-quality laying ducks and obtaining high-quality eggs, thereby earning a certain profit in the market. Not to say they will certainly make a lot of money, but at least they will not spend more than they earn.