Bovine semen collection and processing are the heart of our business. Our semen handling and freezing systems are closely monitored and only semen of the highest quality is released for export or local use. Our laboratory team are qualified in morphology assessment. We can also assess semen by using the CASA (computer assisted semen analysis) system. We can export to most countries around the world, excluding China and the EU.
We have two separate facilities for export semen collection. We have the isolation facility, where bulls spend a minimum of 30 days to have tests for whichever country you would like to export semen to. We also have the licensed collection facility, where the bulls move to after the required tests have been performed – this is also where the bulls undergo semen collection.
The two sites ensure that all overseas health protocol can be catered for. Each of these facilities conforms to the MPI quarantine and health requirements specified by the relevant overseas authorities for the export of bovine semen.
We, in conjunction with Te Pari, have also purpose built four large crushes (pictured below) to fit the biggest of your bulls. These crushes enable the safe handling of your bull, for both his peace of mind and ours!
Semen collection for freezing or for fresh AI can be carried out on your farm. We offer fresh semen collection, same day as your AI. This process can increase your conception rates markedly.
We can work in nearly all facilities that you would normally use to work your cattle, such as cattle yards or cow sheds and yards.
We do prefer to use an in-season cow/heifer of comparable size to the bull for collections as this makes it easier for us, the bull, and the cow/heifer.
If the cow is in season and both she and the bull are moderately quiet, we tend not to restrain the cow. We move them into a smallish yard and walk around with them to collect the semen. This makes the job quick and easy for us all. If an in-season cow/heifer is not available, then a quiet female will be required for collecting.
Bull fertility, or breeding soundness, is the single most important factor to be considered when selecting a bull or ensuring the bulls you used last year are still working and fertile.
The primary components of bull fertility are libido (eagerness to mate), mating ability, penile soundness and semen quality (motility and morphology).
Tararua Breeding Centre and Totally Vets Feilding offer a comprehensive fertility evaluation service. This is an animal welfare friendly assessment of all of the above factors. The procedure is an invaluable management aid in confirming the breeding soundness of stud or paddock bulls prior to sale, or before being turned out for the mating season.
Although Tararua Breeding Centre prides itself in collecting 80% of all bulls using an artificial vagina, we do on occasions find the need to use the electroejaculator on-farm. This is not our preferred method but it is a useful tool when necessary.
The evaluation consists of several parts, which are outlined below.
This involves a physical examination of the ability of the bull to work, including palpation of the testicles and measurement of scrotal circumference.
This gives an indication of the bull’s eagerness to mate and his ability to mount the teaser. An in-season teaser cow is brought into the yards. (For a large number of bulls, the teaser cow is restrained in a specially designed portable crate). The bull is introduced to the teaser and is allowed to mount, and semen is collected into an artificial vagina.
There is obviously a risk, at this time, that the bulls may start fighting prior to, or immediately after testing. To help reduce this risk, we advise that bulls be hungry on the day of collection. This means putting the bulls into a previously grazed paddock the night before collection. Once bulls are tested, they should be taken back into a paddock with good feed, or with supplementary feeding already out there waiting for the bulls.
Each bull’s extended, naturally erect penis is examined during mounting for structural soundness. This is done to detect abnormalities such as corkscrew penis, genital warts, persistent frenulum, hair rings or damage resulting from previous injuries.
The semen sample is then examined under a microscope for volume, density, motility and morphology.
Each semen sample must satisfy our minimum standards for each of these tests before the bulls are passed as fertile. There are several factors that can negatively affect the quality of semen collected on a particular day. Bulls that have been ridden the day before, have been fighting, or have had an injury or illness in the last six weeks, may not work or may have poor semen quality on testing day. If the bull fails the semen test, we do not predict the fertility of a bull based on one isolated semen sample. If the bulls passes all other aspects of the test, then we highly recommend the bull is retested six weeks later.
The examination can be carried out in most stock yards.
All bulls must be healthy on the day of collection.
A quiet, in-season female must be available for the test (or several, if a larger number of bulls are to be evaluated). We will arrange a synchronisation programme to ensure we have a teaser female on heat at the required time.