Reproductive function in purebred Arabian stallions as related to the levels of chemical elements in mane hair samples

In modern animal husbandry, along with the improvement of reproductive technologies, it is becoming increasingly important to restore the natural fertility of livestock, in particular breeding producers. Reproductive function is one of the most sensitive that reacts to changes in biogeochemical and environmental parameters. In this regard, research aimed at studying effects of the level of chemical elements in the body on reproductive function in stallions is rather important. The parameters of sperm quality depending on the level of chemical elements in hair sampled from mane were studied. In this work we used biomaterial of purebred Arabian stallions ( n = 50) of the same biogeochemical province. Reproductive qualities of stallions were evaluated in relation to the pool of chemical elements rated by concentration in the mane hair. All animals were grouped according to the levels of individual elements in hair (i.e. up to percentile 25, within the interval of percentiles 25-75 and above percentile 75). Also the quality of fresh and cryopreserved semen was estimated. Hair profiles was determined for 25 elements (Al, As, B, Ca, Cd, Co, Cr, Cu, Fe, I, K, Li, Mg, Mn, Na, Ni, P, Pb, Se, Si, Sn, Hg, Sr, V, Zn) by inductively coupled plasma atomic emission and mass spectrometry (ICP-AES and ICP-MS). Ejaculate was assessed for volume, concentration, total spermatozoa number, number of spermatozoa with progressive motility and semen viability. The validity of the differences was verified by Mann-Whitney U test. It has been found out that the mane hair analysis can be used to detect reduced fertility in stallions. Increase in average values of Sr to 4.19±0.12, Se to 0,559±0.015, B to 21.55±1.14 µg/g in hair results in decrease in number and activity of sperm and filtrate volume. Activity and survival of stallion spermatozoa after thawing was in inverse correlation with Pb and Sn pool in the body, as determined by element level in the mane hair. With the increase in the concentration of these elements to 0,806±0206 and 0,051±0.008 mg/g, the sperm activity declines after thawing by 3.8-7.7 % and survival by 26.4-29.5 %, respectively. Animals with copper, silicon and vanadium in hair less than that of percentile 25, had the most active sperm. The survival rate of fresh sperm was associated with V concentration in hair being the highest in animals with low levels of this mineral. Thus, the assay of mane hair mineral profile can be used in monitoring for timely correction of stallions’ fertility.