Gender Selected Semen/Sexed SemenBy Dr. Josh Odhiambo

The demand for heifers has grown to an all timehigh due to the 'good' milk prices and the effectof the bungled 2007 elections. Many pedigreeanimals and heifers were slaughtered and others

became internally displaced cattle (iDCs) withvery little care or none at all and soon died. Thatdescribes the local situation.The neighbouring countries are looking forheifers to buy from Kenya in large numbers andare truly disappointed to find that we have noneto sell to them! The belief in the region is that weare the Dairy Country that ought to meet theirrequirements in this regard and indeed weshould!

It is with this in mind that a technology which isgender biased towards heifers has come in handyto help dairy farmers get more heifers. The GenderSelected semen has been in Kenya for about 2

years now and farmers who have used the semenhave pleasant stories to tell."Amazing! It's every dairy mans dream." These aresentiments uttered by Mr. Nyairo and his familywho are the owners of Kalua Farm in Kitale whohas been breeding his virgin heifers with genderselected semen.After what seemed like forever, the thought ofhaving sexed semen biased towards females is nolonger a dream but a reality which is rakingpositive results around the country.

Mr. Nyairo - Kalua Farm in Kitale. No. 1,2,3, & 4.

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Gender Selected Semen/Sexed Semen Cont.

This was achieved after years of research andtesting both in the lab and in the farms with thetechnology first materializing at Select Sires, asubsidiary of World Wide Sires U.S.A. Sexed

semen is sex-sorted semen with upwards of 90%purity to increase the female productionprobabilities which translates to 9 heifers for every10 calves born. To achieve this, sperms are stainedwith a fluorescent dye then diluted for separationthen re-concentrated for freezing. This is done byuse of a high speed sorter called the flowcytometer. The X (female) and Y (male)chromosomes are separated and the X (female)chromosome is retained, reconcentrated andfrozen and used to fertilize the X chromosome inthe female ova of the dam and a XX (female)develops. Separation is based on the fact that the Xchromosome is larger and has about 4% moreDNA than the Y chromosome. After the spermsare treated with the fluorescent dye the Xchromosome due to the higher DNA contentglows brighter than the Y chromosome. Thesperms then flow in the flow cytometer in a singlefile and pass an electrical field and the X and Ychromosome bearing sperms are sorted into

different collection tubes. Sperms flow inthrough the sorter is about 3,000 - 5,000sperms per second and since this flow is slow itcan take about 1.5 hrs for the 20 million straw

to be separated and to decrease the time, thestraw amount is reduced to about 2 millionsperms per dose. Sexed semen is presented in% cc straws thus requires a breeding gundesigned to accommodate this genre of straws.Due to the smaller diameter and compromisedsemen quality they are more sensitive to coldshock and errors in semen handling butthawing and handling is identical to their Vi cccounterparts."They say its at least 90% but with us its been100%; 56 heifers out of 56 conceptions." saysMr. Nyairo who prefers to breed, raise andmilk his own replacements. With sexed sementhere is increased heifer productionprobabilities, reduced calving problems asheifers are bred to have heifer calves andreduction of the generation upgrading periodfor the local national herd as delays that areoccasioned by the occurrence of bull calves areevaded.

Mrs. Nyokabi Kirika - Lone Tree Farm - Roslyn. No. 5 & 6.

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Gender Selected Semen/Sexed Semen Cont.

Sexed semen is found in the highly ranked bulls forfertility based on the conventional semenconception data as well as type and production.Sexed semen is recommended for use in highlyfertile virgin heifers in well managed herds that payclose attention to semen handling and heatdetection due to its compromised fertility orconception state.With sexed semen, conception rates of 50% to 63%can be realized in comparison to the currentlyachievable 70% conception rates with the use ofconventional semen. Low fertility associated withsexed semen is attributed to the immenselydecreased sperm numbers, sperm injury duringsorting and the inability to tell whether a bulls'sperm can withstand the separation process.'Restriction for use in lactating animals isincriminated on the fact that there may be an

incomplete return to normal as well as previous wearand tear of the uterus. It is also noted that lactatinganimals have high nutritional and lactation demandsthus the inherent lower fertility of lactating cows. It'showever prudent to note that gender SELECTEDsemen will not be the 'silver bullet' that cures what ails areproductive or replacementt programme and poormanagement. The farmers who choose to adapt thistechnology must have good management and a goodtechnician to handle the semen and do the ArtificialInsemination.So far over 1,500 Gender Selected straws of HolsteinFriesians, Ayrshires and Jerseys have been used in thecountry with 90% success rate in various farms all overthe milk shed areas.

The cost is slightly higher than the conventionalsemenbutitis "worth it" - farmers say.

"DP TPI & PTAM BULLS AVAILABLE.IFtESULTS HAVE BEEN WONDERFUL.ICENYAN FARMERS ARE CONFIDENT

WITH THIS PRODUCT.

FERTILITY

MANY SIRES OFFERED BY WOULD WIDE SIRES ARE AVAILABLEWITH SEXED SEMEN MARKETED UNDER THEGENDER SELECTED1* FROM SELECT SiRES AND ACC-SS1*FROM ACCELERATED GENETICS, BOTH ARE MADE POSSIBLETHROUGH THE FLOW CYTOMeTRY PROCESS DEVELOPED BY

IN 9O% HCIFCM CALVESWHEN USED ACCORDING TO RECOMMENDATIONS.

GROW YOUR HERD QUICKLY AND EFFICIENTLY WITH SEXED SEMEN FROM WORLD WIDE SIRES

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