An attempt was made to study the effect of Foot and Mouth Disease vaccination on seminal traits of 30 Holstein Friesian bulls ranging between 3 and 5 years age maintained at BAIF Central Research Station Uruli Kanchan, Pune, India. Study period was from August to September 2013 and observations on semen were of bulls maintained under identical feeding and management regimens. Semen collections 15 d before vaccination, 15, 30 and 45 d after vaccination were evaluated for seminal traits such as fresh and post-thaw sperm motility, sperm concentration, semen volume, live and dead count, plasma integrity. Data generated were analyzed using ANOVA. It revealed that vaccination had significant (P < 0.05) effect on post-thaw motility and highly significant (P < 0.01) deleterious effect on host test, head and mid piece abnormalities as it causes derangement in spermatogenesis and epididymal function due to rise in testicular and body temperature; however, no effect was noted on seminal traits such as volume, concentration, initial motility viability and tail abnormalities. There was general decline observed in performance of seminal traits of bulls, confirming the reports of previous studies, which state that the secondary activities following vaccination remain unaltered. Therefore it can be concluded that FMD vaccination causes alteration in spermiogram but functions of accessory sex glands remain unaltered. Hence for better semen picture and to counter the effect, preventive immune enhancement before vaccination and sexual rest for highly affected bulls can be adopted. Table 1. Sperm characteristics before and after vaccination with FMD vaccine

Parameter	Pre-vaccination	Post-vaccination	P-value
Volume (mL)	6.63 ± 0.31	6.42 ± 0.17	0.59
Concentration (millions/mL)	1705.69 ± 86.09	1688.40 ± 43.29	0.88
Initial motility (%)	76.53 ± 0.38	76.3 ± 0.21	0.41
Live and dead (%)	82.89 ± 1.63	80.64 ± 1.03	0.93
Post-thaw motility (%)	58.19 ± 0.41	57.5 ± 0.24	0.03*
Host test (%)	61.53 ± 0.43	60.59 ± 0.21	0.0003**
Morphology
Head (%)	2.78 ± 0.17	3.3 ± 0.12	0.01**
Mid (%)	1.78 ± 0.16	2.41 ± 0.11	0.0001**
Tail (%)	2.08 ± 0.18	2.19 ± 0.09	0.61