Doc. dr. sc. Nikica Prvanović Babić
Klinika za porodništvo i reprodukciju, Veterinarski fakultet Sveučilišta u Zagrebu
SAŽETAKPredavanje sa međunarodnog kongresa: “VETERINARSKA ZNANOST I STRUKA 2013.”
K obile koje se koriste u sportu u rasplodnom su smislu zahtjevne životinje. U vrijeme njihovog intenzivnog korištenja u različitim sportskim disciplinama (galopske trke, kasačke trke, preskakanje prepona, dresura, zaprege) vlasnicima i trenerima je u interesu da se kobile ne tjeraju odnosno da ne pokazuju specifične obrasce spolnog ponašanja. Naime sa kobilama koje se tjeraju puno je teže raditi, ometaju ostale konje prilikom natjecanja i nisu sposobne ostvariti svoj puni sportski potencijal. Također kod kobila koje se tjeraju a dovedene su na trening ili sportsko natjecanje postoji i rizik od neželjenog pripusta. Stoga vlasnici sportskih kobila veoma često traže od veterinara da njihovim kobilama blokiraju ciklus odnosno pripišu određeni oblik kontracepcije. S druge strane, upravo se od sportskih kobila očekuje da se kasnije tokom života uvedu u rasplod i daju zdravu i vitalnu ždrebad čija cijena direktno ovisi o prethodnim sportskim rezultatima roditelja. Ove dvije nepomirljive krajnosti (potreba da se mlade i zdrave kobile ne tjeraju onda kad imaju puni reproduktivni potencijal uz očekivanje da će iste te kobile u zrelijoj dobi postati rasplodna grla) traži precizan i detaljan pristup prilikom prepisivanja, apliciranja i kontroliranja učinaka primjenjene kontracepcije. Metode za kontracepciju kobila dijelimo na kemijske, imunološke, mehaničke i kirurške. Odabir metode ovisi o trenutnoj sportskoj i dugoročnoj rasplodnoj namjeni kobile. Kasnija plodnost ovisi ne samo o dobi već i o dobi prilikom uvođenja u rasplod. Stoga je važno pravovremeno educirati vlasnike kobila o svim prednostima i nedostacima koncepcije i kontracepcije u različitim životnim dobima sportskih kobila kao i o važnosti redovitih ginekoloških pregleda. U svakom je slučaju zadaća veterinara da upozore vlasnike kobila da svoje životinje uvedu u rasplod u optimalno vrijeme i da ne čekaju da kobila uđe u tzv. teenagerske godine jer bi u protivnom moglo biti velikih poteškoća sa koncepcijom. Također postoji opcija, ukoliko vlasnici nisu spremni kobilu povući iz sporta radi gravidnosti i ždrijebljenja, pomoću tzv. nadomjesne majke, kobile primateljice dobiti ždrijebe od željene kobile primjenom metode embriotransfera. Navedena metoda se već dulji niz godina koristi kod polo kobila koje ostaju u sportu dok njihovu ždrijebad rađaju kobile primateljice. Također je važno educirati vlasnike kobila o važnosti redovitih ginekoloških kontrola kobila u sportu još od najranije dobi radi pravovremenog uočavanja svih potencijalno patoloških stanja koji bi mogli ugroziti plodnost i spolno zdravlje kobile. Iako nema podataka kako stres uzrokovan čestim promjenama okoline, intenzivnim treninzima i takmičenjima utječe na organizam kobile i njenu rasplodnu sposobnost, nesumnjivo je da taj utjecaj jednostavno ne može biti pozitivan. Organizam ima svoje granice a na nama je da ih poštujemo. Ukoliko svi uključeni u rad sa kobilom (treneri, jahači, jockeyi, veterinari, potkivači, štalari i sl.) shvate da se radi o živom biću a ne o stroju koji trči i po potrebi može proizvesti i i iz sebe izbaciti ždrijebe, već je pola posla učinjeno. Stoga je osnova kvalitetne brige za rasplodnu kobilu koja je dobar dio života provela u sportu, pažljiv, suosjećajan i dobro informiran pristup neovisno o tome želimo li od kobile dobiti optimalan sportski rezultat ili ždrijebe.Uz sportske kobile za koje dugoročno moramo odlučiti da li i u kojoj mjeri želimo vratiti njihov reproduktivni potencijal, u svijetu i kod nas čest je problem humanog rješavanja pretjeranog razmnožavanja konja koji se drže semiekstenzivno. Uz tradicionalne načine rješavanja problema koji uključuju slanje prekobrojnih konja na klanje te odstrel, sve je češće prisutan i humaniji prostup koji uključuje različite kirurške i nekirurške metode blokade ciklusa kao što su primjena različitih spirala, implantata, vakcina te uklanjanje gonada. Sve nabrojane metode imaju svoje prednosti i nedostatke a odabir metode ovisi o trenutnoj i trajnoj namjeni i vrijednosti kobile.
v. VETERINARSKA ZNANOST I STRUKA 2013.
SUMMARYA lecture from the International congress: “VETERINARY SCIENCE AND PROFESSION 2013.”Temporary and permanent oestrus suppresion of mares
Doc. dr. sc. Nikica Prvanović Babić
Clinic for obstetrics and reproduction, Faculty of veterinary medicine, University of Zagreb, Croatia
Owners of mares used in different sport disciplines (jumping, racing, trotters etc.) often seek veterinary advice considering estrus supression for their mares. Namely, competition season is ussually followed by cyclicity. Mares in heat often are moody, have difficulties to concentrate and fail to gain best possible results. Furthermore, when travelling to competitions there is allways possibility for unwanted mating and consequently pregnancy. More or less, situation is controversial. Mares need to gain good results to ensure better prices for their potential offsprings later. In the same time, reproductive traits and cyclicity could directly have negative influence on their performance as sport or racing animals. Furthermore, some of contraceptive agents routinely used for oestrus suppresion could have longterm negative effect on fertility and reproductive performance. Keeping in mind the fact that the same animals should become broodmares later in their lifes, it is essential to perform detail and precise approach when dealing with such situation. Estrus supression of mares could be achieved using chemical, immunological, mechanical and surgical methods. Some mares that are not suitable for oestrus suppression could be candidates for oestrus translocation (induction of oestrus earlier to avoid sendinfg mares in heat to competitions) or just contraception (blockage of conception or pregnancy termination). Some animals could benefit from NSAID therapy (with or without other mentioned methods) since some mares experience pain and/or discomfort during oestrus (caused by softening of muscles and ovulation) and sometimes is good enough to relieve the pain and animal is much more cooperative and easier to handle. However, method of choice depends of current sport and future reproductive destiny of the mare. Future fertility depends not only on mare’s age but also on age at first cover or A.I. It is very important to educate mare owners and start with regular veterinary examinations of mare reproductive tract to keep her healthy and fertile. It is also crucial to inform mare owners about risks of subfertility or/and infertility of mares that are introduced to breeding too late i.e. in teenager years since its reproductive effiviciency decreases rapidly after 15.-th year of life. There is allways an option to use some of methods of assisted reproduction like embryotransfer (used routinely in valuable polo mares whose foals are delivered by recipient mares since donors are used in sports) or taking a year break for pregnancy, parturition and nursing during competition career of mare who will physically and psyhologically benefit of it. Furthermore, although there is no scientific data about influence of stress caused by intensive trainig, competitions and transport it is clear that such influence simply couldn’t be good and positive since it is in strong opposition to natural insticts and lifespan of breeding mare. Keeping in mind all numbered facts it is easy to see how important is to have empathic, good informed and sensitive approach when prescribing contraceptive agents to different categories of sport and working mares. Contraception tehniques used for oestrus suppression is not limited only for sport and leisure animals. Oestrus suppression and/or pregnancy termination is up to date tehnology for population control of semiferal horses. Although there are still more traditional ways in usage such as sending overpopulated and unwanted horses to slaughterhouse or shooting of excessive animals, there is increased need to introduce new, modern and more humane methods such as nonsurgical castration i.e. vaccination against different factors involved in fertility, application of intrauterine devices to prevent pregnancy development and ovariotomy. All numbered methods have adventages and disadventages and method of chioce strictly depends on value, accesssability and usage of particular mare.