methods of mating and artificial insemination in poultry

Upload: abidaiqbalansari

Post on 10-Oct-2015

8 views

Category:

Documents


1 download

DESCRIPTION

poultry breeding

TRANSCRIPT

Methods of Mating and Artificial Insemination in PoultryNilufar HaquePh.D. Scholar, Dairy Cattle Physiology Division& Sk Asraf HossainPh.D. Scholar, Dairy Cattle Nutrition DivisionNational Dairy Research Institute, Karnal, HaryanaIntroductionThe number of females to be mated to each male varies depending upon the breed, age, health, and sexual activity of the male. In general, the males of light breeds like leghorns are more active and vigorous than the males of heavier breeds such as white Plymouth Rock and Rhode Island Reds. Older males are usually capable of caring for fewer females than cockerels. Spermatozoa are able to live in the oviduct for at least 5-11 days in ducks, geese or fowl and three weeks in turkeys, and during this period a succession of eggs in a hen is fertilized after a single insemination. Methods of mating:The following methods of mating are generally used:[A] Natural mating1. Pen mating1. Flock mating1. Stud mating1. Shift mating.[B] Artificial insemination[A] Natural Mating In this method of mating males are allowed to mate with females naturally. This mating method can be categorized as following:[1] Pen Mating1. Usual method of mating used for pedigree hatching.1. A group of hens are allowed to mate with a cock in a pen.1. The mating pens are of 8ft x 6ft size.1. The male to female ratio is 1: 10 or 12 for light breeds and 1: 8 or 10 for heavy breeds.1. The fertility is lower in this mating compare to flock mating due to preferential matings i.e. a male may mate more frequently with certain females than with others. The preference for mating is generally attributed to plumage colour etc.[2] Flock Mating1. It is mass mating system wherein two or more males are mated with several females housed in single pen.1. Male to female ratio is generally higher in this method i.e. one male for 12 to 15 females of light breeds and 10 to 12 females of heavy breeds.1. From pedigree hatching point of view, the eggs cannot be identified for their parentage.1. Under this system, sometimes the aggressive males scare away other males preventing them from mating. Such aggressive males should be removed from the flock.1. This method also provides an opportunity for the birds to mate with the mates of their choice whereas there is no such choice in stud or pen mating.1. The fertility is generally high and, therefore, much desirable for producing chicks meant for commercial purpose.[3] Stud Mating1. In this type of mating the male is kept separately in coop or pen (2 ft * 3 ft size).1. The females are picked up from the pen one by one and put into the coop. After the mating is accomplished, another female and so on replace the female.1. In comparison to flock or pen mating, it involves more work and labor.1. More offsprings can be obtained from sire of high merit.1. By this method it is possible to mate one male to many females.1. To ensure good fertility, the hen should be stud mated at least once a week.1. As compared to flock or pen mating this method results in higher fertility.1. This method of mating can also be employed if the birds are kept in the cages.[4] Shift Mating1. In this type of mating the sires are shifted in breeding pens.1. This method can be employed in breeding programs (family breeding) where the breeding value of more number of males needs to be tested for locating really superior males.1. At the same time by shifting the male, a female can be mated with several males and her breeding worth can be evaluated more precisely.1. The major hindrance in shifting of males in a breeding pen during the season is the problem of accuracy of the parentage of the progeny since the fertility is maintained for 2-3 weeks even after removing the cock.1. This difficulty may be overcome by discarding the eggs for one week after the change of males.1. The main advantage of this system is that a large number of males can be tested in a limited space.1. The pen mating doesnt differ from this system except the mates are shifted from one pen to another in a sequence.[B] Artificial InseminationArtificial insemination (A.I.) means the deposition of semen into reproductive tract of female by some means other than natural mating. In various poultry breeding projects the artificial insemination has gained considerable attention.HistoryArtificial insemination has been widely applied to poultry. Semen collection, processing, and AI have been reviewed by Sexton (1979) and Lake (1986) and more recently by Donoghue and Wishart (2000). Pioneers in the poultry field were Burrows and Quinn (1937), who developed the method of abdominal massage and pres-sure to collect semen. With the ease of collecting poultry semen, and proximity of hens on large breeding farms, AI is used extensively with freshly collected semen. It is used 100% for turkey breeding because mating is difficult. Freshly collected chicken semen was among the first type of semen to be frozen (Shaffner et al., 1941; Polge et al., 1949). However, cryopreserved poultry sperm are less fertile and freezing poultry sperm still is experimental (Gill et al., 1999).This procedure consists of collecting semen from males and inseminating into females. The major use of A.I. is in heavy birds whose fertility is generally low under pen mating. It is also practiced when the layers are kept in cages. Adopting A.I. as well as service of a valuable male can be extended can increase fertility. The practice of A.I. requires some training on the part of both operator and the male.It is a valuable technique in avian species. It is ordinarily practiced when the flock presents an apparent fertility problem. Excellent fecundity has been obtained by the use of artificial insemination (A.I.), better in many instances, than that obtained by natural mating. The A.I. of domestic fowl is not widely used on commercial farms. On the other hand, turkey breeders use A.I. extensively to propagate their stock, especially the large Broad Breasted Bronze strains that experienced difficulty in mating naturally. Technique for artificially breeding ducks and geese are available but large-scale breeding programme using such methods have not been applied except perhaps with certain breeds of ducks in the far east.Psychology:Psychological factors influence the amount of semen that can be extracted from the reproductive tract. The extent, to which an operator has to struggle with a male, before it is captured and restrained, varies tremendously. In general, the greater the struggle the smaller the amount of semen obtained.Turkeys, ducks and geese require more training for handling than most breeds of domestic fowl, even without a struggle. Occasionally some males never respond properly to stimulation for semen collection. How far this is due to psychological factors or to inherent defects of physiology is not known. To bring the males into maximum semen production, it may be desirable to train them by handling on alternate days for a period of a week or more before the first insemination date. Advantages of Artificial Insemination in Poultry1. Efficient use of males: - Requirement of males is lesser in A.I. compared to natural mating which will reduce the rearing cost of males and increases the intensity of selection.1. Multilocational testing of outstanding sires. 1. Avoidance of preferential mating and physical incompatibility.1. Production of fertile eggs from layers in cages is possible.1. Accurate recording of pedigree is possible.1. Fertility is 5-10% higher in A.I. as compare to natural mating.1. Interspecies hybridization is possible.1. Use of large male with small female and vice versa is possible.The Process of Artificial Insemination Includes1. Preparation of Males1. Preparation of Equipments1. Collection (Milking) of semen from Males1. Evaluation of Semen1. Dilution of Semen and1. Deposition of Semen in Vagina of Female1] Preparation of malesMales used for A.I. should be healthy vigorous and free from any physical abnormality or disability. They should be placed on balanced breeder ration a month before actual collection is to be practiced. The male birds can be housed in individual cages, but they need to have enough room to be able to crow. A suggested cage size is 45 cm wide, 60 cm deep and 60 cm high. The feed and water containers should be hung on the outside of the cage. Male birds respond to the people handling them and a quiet, unhurried approach is necessary with careful handling. During the collection of semen, it is essential that visitors remain outside the shed. This will prevent the birds from becoming frightened. It is a good idea that the males are housed in close- proximity to the hens so that the time between collection and insemination is kept to a minimum. Prior to use, the selected male birds should be examined for external parasites, particularly poultry lice, and treated accordingly. It is also a good idea to clip the feathers from around the vent area to give easy access to the male organ. This applies particularly to loose-feathered breeds of poultry. Each and every male should be tested for production and evaluation of semen before used for A.I.2] Preparation of equipmentsThe equipments required for A.I. are-1. Semen collection funnels/cups: - Glass or plastic funnel of 3cm diameter with stem blocked with paraffin.1. Glass/ tuberculin syringe.1. Test tube stand/ rack for holding of funnel/cup3] Collection of semen from males (milking)The cock should be held in the left hand, head extending under the arm. The soft sides of its abdomen between the gizzard and the pelvic bones should be massaged with right hand in order to stimulate the ejaculatory organ. The fingers of the right hand are outspread at the start of the stroke but brought together at the end of the stroke so as to converge on the vent. The stroking of males back should be done moving the hand in the direction of the birds vent only. Such a stimulus causes the trained male to evert or protrude the vent region. When this occurs, a quick motion of strokes will cause the male to ejaculate. The squeezing pressure is applied by the thumb and index finger inward and downward at a point just above the vent. The semen is collected by an assistant in an A.I. funnel by holding it under the vent.Precautions while collecting the semen1. The males should be separated from females at least one week before an attempt is made to collect the semen.1. The feathers around the males vent should be plucked off to obtain the semen easily.1. Collection of semen may be carried out daily depending upon the need. However, thrice a week collection will give maximum number of spermatozoa over a long period of time.1. The semen contaminated with foreign material like urine and faeces should not be used.4] Evaluation of semenSemen is a mixture of sperm cells and carrying fluids. In domestic birds the ejaculate is characteristically highly concentrated and low volume. The composition of semen obtained while artificial collection is quite variable, the sperm cells being mixed with secretary fluid from the engorged phallic apparatus and some time mixed with digestive & urinary tract wastes. The contributions of these factors are not easily controlled & consequently considerable variation in semen composition has been reported. The fertilizing ability of semen depends upon its quality. Semen can be evaluated on the basis of volume, colour, pH, motility of the spermatozoa, sperm concentration, percentage of live, dead, and abnormal spermatozoa etc. Good quality chicken semen is pearly white and opaque. The semen volume is about 0.5-0.75 ml/ejaculate with sperm concentration 4 billion per milliliter.5] Dilution of semenThe spermatozoa begin to lose their integrity after collection, which results in reduced fertility. As a practical matter it is prudent to use semen within 30-45 minutes of collection. In laboratory conditions excellent fertility levels have been reported with chicken & turkey semen held unfrozen invitro for 24 hours or more.Diluents increases the volume of semen, retains cell integrity and buffering the detrimental effect arising on storage. In general if semen has to be stored beyond 1 hour after collection, dilution with ideal extender and careful handling is essential.Successful short-term preservation of unfrozen avian semen requires the collection of clean, high quality samples and careful handling of the semen after collection. Storage condition and diluents used for storage have differed markedly. With most diluents, avian sperm survive best when kept cool (5-15C) but excellent fertility has also been reported when chicken sperm were held in minimum essential medium at 41C for 24 hours.Progress towards long-term preservation of frozen chicken & turkey semen is being made. Better fertility has also been obtained with frozen chicken semen than with frozen chicken semen than with frozen turkey semen. Levels of fertility obtained with frozen chicken semen are high enough to allow conservation of selected germplasm by poultry breeding organizations but too low to allow wide spread commercial use.The some of the diluents used for dilution of chicken semen are 1. Ringers solution1. Simple saline diluent1. Sodium citrate buffer1. Glucose citrate solution1. Lakes diluent1. Tris- yolk extender buffer1. Mac Phersons extender1. Belts ville poultry semen extenderTable 1. Composition of Ringers solution (commonly used)CompositionQuantity (g)

Sodium chloride (NaCl)9.00

Potassium chloride (KCl)0.25

Calcium chloride (CaCl2)0.30

Sodium bicarbonate (NaHCO3)0.20

These are dissolved in distilled water to make the total volume 1 liter. The pH of this solution should be 7.Table 2. Modified Ringer's solution.CompositionQuantity

Sodium chloride68 g

Potassium chloride17.33 g

Calcium chloride6.4 2 g

Magnesium sulphate2.50 g

Sodium bicarbonate24.50 g

Distilled water10 L

The concentrated semen can be diluted by using extenders to inseminate more number of females. However, the A.I. should be done as early as possible after dilution because fertilizing capacity of avian species is quickly degenerated on storage. The diluent should be added at a ratio of 1: 2 4.

6] Insemination of semenThe recommended dose for undiluted, good quality semen is 0.03 ml/week but for diluted semen dose varies from 0.03 to 0.05 ml/every 3 4 days to maintain good fertility. To obtain optimum fertility 80 to 100 millions sperms / ml is recommended hence; the required quantity of semen is to be taken in syringe for insemination.The process includes1. Eversion of vagina1. Deposition of semen.The process of insemination requires two men. One man with his left hand holds firmly the lower thighs of the hen and with the right hand applies pressure on the abdomen below the cloaca to evert the vagina. As the vagina is everted the second man gently inserts the inseminating syringe to a depth of 3 cm into the oviduct.The semen is released from the syringe; simultaneously the pressure on the abdomen is released to allow the oviduct to resume its normal position.Soon after the insemination, optimum number of spermatozoa enters the primary storage glands (sperm storage glands) at utero vaginal junction. Sperm are seldom found in the infundibulum storage site unless semen is introduced into the oviduct in such a manner that it bypasses the utero vaginal glands. Fertilization of egg takes place in infundibulum. Thus after a single mating or insemination eggs received up to 3 to 4 weeks will be fertile but the fertility will be reduced with time advances.For good results1. Insemination should be done when no hard-shelled egg is present in the uterus preferably during late afternoon hours.1. Avoid any kind of stress to the birds before insemination.1. A.I. equipment should be thoroughly cleaned and properly sterilized before use.1. The intervals between inseminations should be strictly maintained.1. For good fertility A.I. should be done twice a week.REFERENCES:Brillard J.P. and De Reviers M. 1998. Artificial insemination in the hen. Physiological basis and control of the fertilizing rate of eggs.INRA Prod. Anim., 2(3): 197-203.Burrows, W. H., and J. P. Quinn. 1937. The collection of spermatozoa , from the domestic fowl and turkey. Poult. Sci. 26:1924.Burton H.W. 1989. An article from the Australasian Poultry Artificial Insemination its use in Poultry BreedingCooper D.M. 1965. Artificial Insemination in Poultry.World's Poult. Sci. J. 21: 12-22.Donoghue, A. M., and G. J. Wishart. 2000. Storage of poultry semen.Anim. Reprod. Sci.62: 213232.Foote R.H. 2002. The history of artificial insemination: selected notes and notables.J. Anim. Sci.80: 1-10.Gill, S. P., R. H. Hammerstedt, and R. P. Amann. 1999. Poultry artificial insemination: Procedures, current status and future needs. In: Proc. Annu. Mtg. Soc. Theriogenology, Nashville, TN. pp. 353362.Koohpar H.K., Sayyahzadeh Y., and Pirsaraei Z.A. 2010. Comparing the natural matingwithartificial insemination(A.I.) at Mazandran native hen.Inter. J. Poultry Sci. 9(7): 11-15.Lake P.E. 1986. The history and future of the cryopreservation of avian germ plasm.Poult. Sci.65: 115.Polge C., Smith A.U. and Parkes A.S. 1949. Revival of spermatozoa after vitrification and dehydration at low temperatures.Nature(Lond.) 164: 666.Sexton T.J. 1979. Preservation of poultry semena review. In: H. W. Hawk (ed.) Animal Reproduction. Beltsville Symposia in Agricultural Research, No. 3. pp 159170. Allanheld, Osmun & Co., Montclair, NJ.Shaffner C.S., Henderson E.W. and Card C.G. 1941. Viability of spermatozoa of the chicken under various environmental condi-tions.Poult. Sci.20: 259265.Singh R.P. and Jitendrakumar 1994. Biometrical Methods in Poultry Breeding , Kalyani Publ. (Ludhiana).

Page 7 of 7