Impact of selected Infectious diseases on reproductive performance in cattle

1. Impact of selected Infectious diseases on reproductive performance in cattle MSD AH Animal Middle East Symposium Beirut 2012 Monika Ptaszynska, DVM, PhD Global Marketing and Technical Director Ruminant Reproduction and Uterine Health Brought to you by Partners in Reproduction Health Platform

2. Contents • Introduction • Infections with negative impact on the ovarian functions and higher endocrine regulatory centres. Example – BVDV infection. • Infections causing embryonic and foetal mortality. • Unique interaction between infectious factor and the dam’s organism in Neospora caninum infection. • Infections associated with uterine disorders. • Infections affecting the quality of semen. • Diagnostic decision tree. • Safety precautions.

3. Introduction • Infectious causes of reproductive failure in cattle – why so important in • daily veterinary practice…. • They can have deep and multidirectional negative effect of herd’s reproductive performance and therefore also on its profitability. • Some of them are zoonotic and can represent a risk to the personnel, veterinary practitioner or even the consumer of products derived from affected animals. • Usually these infections find themselves at the very end of the routine diagnostic process employed in cases of fertility problems in the field and even if abortion took place only a small percentage of cases is given the correct diagnosis. • Nowadays, veterinary practitioners have very good diagnostic methods and prophylactic measures at their disposal to address the majority of these infections.

4. It is not only about abortions…

5. Embryonic phase (<42d) Fetal phase (>42d) Calving Follicular phase General timelines for selected infections affecting reproductive performance in cattle Neospora caninum Trichomonas foetus BTV L.interroganspomona Leptospira interrogans L. interrogans hardjo Fungal inf. mastitis BVD Toxoplasma gondii, N.caninum, Akabane, SBV mastitis IBR BHV-4 (?) Brucella abortus BVD IBR C. Fetus venerealis BVD IBR Impaired follicular growth, ovulation disorders, silent heat Luteal deficiency, embryonic mortality, repeat breeding Abortions during the 1st half of pregnancy Abortions in the 2nd half of pregnancy, often with placental retention Stillbirth or weak calves Endometritis Still very limited data for SBV

6. Infections affecting ovarian functions and higher endocrine regulatory centers

7. Let’s take a closer look… Clinical picture at the herd level: low heat intensity, low efficacy of AI, early returns (<25d postAI.)

8. McGowan et al. (2002) – viraemic cows showed decreased or practically absent preovulatory • estradiol peak • As well as delayed and decreased preovulatory LH surge No E2 surge! Dramatyczny wzrost poziomu progesteronu

9. McGowan et al. (2002) • And what happened with progesterone production in infected cows… Significantly delayed and poor increase in progesterone levels “Healthy” post ovulatory progesterone rise Practically no progesterone rise From Fray et al., 2002 Conclusions: such a low and delayed post-ovulatory progesterone production will not be adequate to support early embryonic development and pregnancy recognition

10. Infections causing directly embryonic and fetal mortality

11. What will happen in the herd… Clinical picture in the herd:repeat breeding (especially late repeats >25d post ins.), increased inter-estrus intervals

12. What will happen in the herd… Clinical picture in the herd:abortions, placentitis

13. Clinical picture in the herd:abortions, placentitis

14. Unique interaction between infectious factor and the dam’s organism in N.caninum infection • Important role of the specific immune situation of the pregnant cows (immunotolerance of fetal antigens) and activation of the immune response in face of the parasite re-activation (Innes i wsp., 2007). In order to maintain pregnancy (semi-allogenic transplant) the maternal organism gives preference to regulatory cytokines:IL-10, IL-4, TGFb, having an opposite effect to inflammatory type cytokines(INT) Infection with N. caninumusually induces cellular immune response with important participation of lymphocytes T andINT  Immunosuppressive effect of progesterone???? It is thought that the natural immuno-modulation that guarantees pregnancy maintenance may impair the ability of the cows to mobilize the cellular immune response adequate for elimination of the parasite. It is also postulated that apart from the direct effect of the parasite on the fetal development, the immune response activated within the placenta may have a fetotoxic effect and lead to abortion.

15. Infections typically accompanied by endometritis

16. Infections affecting the semen quality

17. Orientation diagnostic decision tree

18. What are our possibilities for diagnosis and control in some of the infections?

19. On the safety… • Due to the zoonotic potential, care should always be taken when handling the abortion material to ensure safety of the veterinary surgeon, their assistants and bystanders. • Adequate instruction should be given to the owners and personnel in contact with aborting animals to ensure their safety. • If an infectious cause of the abortion/stillbirth is suspected the affected animal should be isolated, the place where abortion took place cleaned and disinfected and the abortion material safely disposed after the adequate samples have been collected. • In particular pregnant women and women of child-bearing age should avoid contact with aborted material.

20. Thank you very much for your kind attention Questions…