MINISTRY OF LIVESTOCK DEVELOPMENT SMALLHOLDER DAIRY COMMERCIALIZATION PROGRAMME. Artificial Insemination (AI) Service

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1 MINISTRY OF LIVESTOCK DEVELOPMENT SMALLHOLDER DAIRY COMMERCIALIZATION PROGRAMME Artificial Insemination (AI) Service 1

2 1.0 Introduction The fertility of a dairy cattle is very important for a dairy farmer as it affects the number of calves born and the total milk production during the lifetime of the cow The fertility status of a herd or cow is often measured by means of the calving interval the period measured in days between two successful calvings The calving interval is usually the period from calving to conception plus the period from conception to the next calving Normally, the pregnancy period of a cow is more or less constant: on average 280 days This means that a long calving interval is caused by a long interval between the date of calving and the date the cow conceives again Thus the farmer should ensure that the cow conceives as early as possible after calving has taken place This will involve proper breeding by using of natural mating or artificial insemination By far the most economical method for a farmer to obtain improved dairy calves is through artificial insemination 2.0 What is artificial insemination (AI) service? It is the process of depositing semen in the uterus of a cow by use of equipment instead of allowing natural mating AI is widely practiced in cattle and semen is collected from selected bulls in an hygienic environment Two types of semen are commonly used: o Liquid or room temperature (RT)semen o Deep frozen (DF) semen usually distributed in containers filled with liquid nitrogen which helps to keep the semen in deep frozen condition 3.0 Benefits/Advantages of AI Service Allows the farmer to select semen for performance (e.g. for milk production) One bull can be used to inseminate many cows Semen can be removed and stored even after a bull dies It is easy to transport semen than the cows to the bulls AI controls the spread of sexually transmitted diseases Selective breeding is possible (according to the farmers objectives) 3.0 Steps involved in a successful AI service Selection of the bulls Semen extraction from the bulls 2

3 Semen processing and storage Semen transportation to the farms Actual insemination 4.0 Pre-requisites for successful AI service Appropriate equipments (may often be expensive) Trained AI technicians who have to follow all the recommended semen handling steps strictly Proper knowledge of the signs that indicate when an animal should be served ( heat detection) Keeping of proper records (otherwise inbreeding can occur accidentally) Reliable infrastructure for effective semen transport 5.0 Obtaining good offspring from AI Service The most important and most frequently missed opportunity for dairy farmers to become successful and prosperous is in the detection of estrous (heat) to ensure the animals are mated/inseminated The farmer needs to target insemination in order to ensure cows become pregnant again as soon as possible after calving down After calving, the cow comes on heat (and is ready to be mated/inseminated) around day The aim is to serve the cow days after calving to get a calf every year Hormonal changes cause the cow to come on heat and release an egg Poor heat detection is a major cause of failed conception in AI services and therefore it is important to precisely detect heat and properly time the insemination Heat detection is usually improved if one knows when the cow is expected to be on heat and practice regular daily herd observation Observing the animals 3 times a day for about 30 minutes each time is adequate. Heifers and confined cows (in zero grazing units) require closer observation for heat signs 6.0 Signs of heat in cattle The surest heat sign is when a cow allows other animals to mount her while she remains standing. Heat signs are shown in three different phases Early heat, Standing heat and Late/after heat; Early heat signs (1 9 hours after the heat cycle begins): o Increased restlessness o Mounting other cows o Swollen vulva 3

4 o Sniffing other cows and being sniffed o Cow bellows o Reduced feed intake and this will be reflected in a decline in milk production if the cow is in lactation NB: During this period the farmer is required to watch the cow closely Standing heat signs (9 20 hours after the heat cycle begins) o Mounts other animals and standing when mounted o Clear mucus discharge/flow from the vulva o Bawls frequently o May stop to eat and hence sharp decline in milk production o Tail bent away from the vulva NB: During this stage the cow should be taken for service!!!! Late/after heat o Cows no longer stands to be mounted o Dried mucus in the tail o Roughened tail head o Bloody discharge (very late!!!!) NB: During this stage the farmer should only note and record the date 7.0 Insemination and ensuring conception Animals detected on heat in the morning are inseminated in the afternoon and those detected in the afternoon or evening inseminated the following morning, i.e hours later. Once a cow is presented for insemination: The area around the vulva should be clean, with no dirt and/or foul/smelly discharge The inseminated animal should be allowed to rest for about 30 minutes, to avoid semen flowing out The animal should be well fed so as to maintain a good body condition NB: Some pregnant cows may show signs of heat. Before a cow is inseminated, make sure that it is not pregnant by seeking the services of an animal health professional to undertake a pregnancy diagnosis 8.0 Identifying the breeds used in the insemination In Kenya, semen used is obtained locally (from CAIS) and imported from other countries The local semen from CAIS is obtained from all common dairy breeds in the country e.g. Friesian; Guernsey; Ayrshire and Jersey Locally, breed semen used can be identified through the number code on the straw or on the AI ticket 4

5 Each bull has its own unique number usually made up by 2 or 3 digits. Thus Ayrshire bulls have numbers from 01 to 199; Friesian bulls have numbers starting with 2 or 3; Guernsey bulls with 4 and Jersey with 6 NB: For the different companies producing semen used in Kenya, there is a Bull Catalogue which gives the details of the important traits that can be improved by using the specific bull. It is recommended that farmers seek the advice on how to use the bull catalogue. Contact Programme Coordination Unit Tel: [email protected], [email protected] website P.O. Box Nakuru, Kenya. 5