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• Preg Testing - Avoiding Errors

Preg Testing - Avoiding Errors

The process of using pregnancy diagnosis by rectal palpation to ascertain when a cow is going to calve is very useful and has become an integral part of dairy reproductive management.  The ability to use these results productively depends on a number of factors.  The most important of these is the confidence we can have in the expected calving date produced for a cow being the actual date the cow will calve.  Greater confidence in this aspect can make it easier to make decisions on dry off dates, induction programs and culling decisions.  Constantly we find that the accuracy of the relationship between an expected calving date produced from a PD session and the actual calving date of the cow varies from farm to farm.  Why is this so?

The process of presenting a cow for examination, having her examined, taking a record of the result and transferring that record to a reproducible and storable form has many steps.  It is essential to examine all those steps to ensure that as many deficiencies are eliminated.

Presenting the cow for examination

• Identification - Having a reliable, readable and readily accessible identification.  ID is critical.  If cow identification is inadequate, PD examinations are useless.  The ideal is to have a readable freeze brand combined with an ear tag, preferably one in both ears.  Freeze brands and ear tags can both become illegible.  Having one backing up the other gives a good insurance against mistakes.  This may seem like a bit of overkill to some.  Let those skeptics be assured, in herds where this is done the entire process works far more efficiently.  There is less hassles with drafting cows, if required, and with preg testing them with out holdups to get an accurate ID on a cow.

• Grouping - Ensuring the cows are in a manageable group.  Attempting to draft cows off during the PD session can be frustrating for all involved, including the cows.  With rotary systems, a subgroup of cows can be done in the herd during milking, however a small group may become expensive to do when it requires having a vet standing around for an entire milking.

Examination of the cow

• Operator Competence - We strive to ensure any professional examining a cow is competent to give the result required.  Obviously we are going to have vets of different levels of experience available at any one time.  Each vet in the practice goes through a rigourous training and evaluation process to ensure they are competent.  The main difference in abilities seen, once adequate competency is gained, is in the number of PDs  different vets can do in one session

• Operator Fatigue - With experience, greater number of PDs can be done in one session.  Nowadays we try to do any herds over 150 cows in teams of, 2 up to 5 vets to ensure fatigue is avoided.  From a clients point of view this not only ensures as good a result as possible is obtained but that the job is done as quickly as possible.  When booking herd PDs in, it is essential to give an accurate indication of the numbers involved to allow adequate arms are available.

• Safe facilities - It is more difficult to concentrate on doing an accurate job when trying to avoid injury at the same time.  Facilities have improved significantly over the years.  Some farms still have dangerous aspects to their facilities.  We will be attempting to contact those enterprises this year to help them improve their facilities to make the entire process more enjoyable for man and beast.  If you are not sure of the adequacy of facilities please phone and ask for one of the partners to come out and discuss the options with you.  We have some comprehensive design diagrams that can be used.

Record Keeping

• Storage - For many, heat and mating records can be stored on a simple wall chart and provide adequate information.  With increasing herd size and the advent of more split calving patterns this method can prove inadequate.  The use of computer record systems makes the job easier and more accurate.  Many programs are available.  For more information on this contact the office.

• Retrieval - Obviously this is easier with a good computer system.  A good knowledge of computers is essential to avoid having the situation of loads of good information sitting in a broken down computer and inaccessible.  We are able to provide a service for computer herd reproductive recording if required.  Many farmers will use this if they are not familiar with computers but want  to be able to access data in this fashion.

• Information on the day - The ideal situation is to have a list of all cows to be examined and the number of weeks since their last recorded service.  It is important not to spread this list out over too many pages.  We find that 150 cows to a page of three columns works pretty well.  With less pages, cows information can be found with out flicking through a large number of pages each time.

• Adequate record keepers - It is very difficult for one person to keep up with more than one PD operator if they are retrieving service information for each cow.  Some herds have the system finely tuned to the stage where they can cope.   It is unwise to assume this is the case in your herd.  It will slow down the process and can be a potential source of major errors in the results.  It is surprising how often an incorrect result is recorded due to a record keeper trying to record information from more than one operator.

• Transferal to storage - Ensure the process of transferring PD results to permanent storage is as easy and foolproof as possible.  Set aside specific time to do this with no interruptions and hopefully when not tired. Any errors in record keeping will not show up until calving time.  By then it is too late.  This is one of the most critical factors in poor results.  There is only one chance to get it right at this stage.

Obviously there are many aspects that have still have not been covered.  We would urge you to contact us if you have any questions.  It is more difficult to correct deficiencies in the system on the day of the session with a herd of cows in the yard.  Often we have not moved to help correct an obvious problem because it is often possible to get through with what is available and it is over for another year.  This has been at the cost to being able to help everyone do a slightly better job.

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