The effect of trace mineral i̇njections on serum trace mineral levels and reproductive parameters i̇n ewe synchronized during anoestrus

With the presented study, it was aimed to investigate the effect of trace mineral injection before progesteron based oestrous synchronization on some serum trace mineral levels, oestrus and some reproductive parameters in Awassi ewes. In the study, 300 ewes between 2-5 years old with a body condition score of approximately 3 were randomly divided into 3 equal groups. In the trace element (Group trace, n=100) group, 2 ml of trace mineral (Activate®, Alke, Turkey) was administered intramuscularly 14 days before the oestrus synchronization application. In the control group (Group control, n=100) and NaCl group (Group NaCl, n=100) 2 ml 0.9% isotonic NaCl was administered intramuscularly. Ewes in trace element and control groups were placed intravaginally with sponges containing 60 mg MAP (Esponjavet®, Hipra, Spain) for 12 days. Oestrus synchronization was not applied to the NaCl group. On the day the sponges were removed, 500 IU eCG (Oviser®, Hipra, Spain) was injected intramuscularly to the sheep in the trace mineral and control groups and 5 ml of 0.9% isotonic NaCl was injected to the sheep in NaCl group. Serum copper, zinc and manganese levels were determined via blood samples 3 times, before the trace mineral injections, on the days when the sponges were placed and removed. 24 hours after the sponges were removed, ewes were hand mated with rams for 4 days, every 12 hours between 06:00 and 08:00 in the morning and 18:00-20:00 in the evening. Serum copper level (µg/L) was 1085±103, 1009.4±99.2 and 1045.3±51.7 in group trace, 977.6±49.2, 1096.4±86.8 and 1159.6±70.6 in group control and 958.0±79.7, 1027.3±63.4 and 1002.5±34.7 in group NaCl; serum manganese level (µg/L) was 1.976±0.135, 2.036±0.123, 1.956±0.129 in group trace, 1.834±0.138, 1.8878±0.0728, 1.8597±0.0802 in group control and 1.8164±0.0795, 1.9636±0.0602 and 1.8023±0.0852 in group NaCl; serum zinc level (µg/L) was 674.8±14.9, 696.1±21.4 and 667.92±8.00 in group trace, 673.9±25.8, 635.22±9.97 and 665.9±12.1 in group control and 708.7±21.7, 684.1±35.7 ve 734.5±15.4 in group NaCl respectively. In the statistical analysis, no significant difference was found between the groups in terms of serum copper, zinc and manganese levels in the 1st, 2nd and 3rd measurements (p>0.05). Since estrus activity was not observed in the NaCl group, reproductive parameters were not evaluated in this group. The time between eCG treatment and the onset of oestrus (hours) 38.069±0.789, 36.837±0.743; mean duration of estrus (hours) 29.655±0.958, 26.093±0.872; the incidence of oestrus is 87%, 86%; conception rate 75.86%, 73.25%; pregnancy rate 66%, 63%; lambing rate 62%, 59%; singleton birth rate is 59.67%, 59.32%; multiple birth rate 40.32%, 40.67%; twin birth rate 35.48%, 35.59%; triplet birth rate 4.83%, 5.08%; dystocia rate were 14.51%, 10.16% in Group trace and control, respectively. Ninety lambs from group trace and 86 lambs from group control were obtained. It was observed that the mean duration of oestrus lasted longer in group trace and this was statistically significant (p<0.05). In Group trace, the time between eCG treatment and the onset of estrus, estrus, conception, pregnancy, lambing, single birth, difficult birth rate and total number of lambs; in the control group, the rate of multiple, twins and triplets was higher numerically, but no statistically significant difference could be determined between the groups (p>0.05). As a result, it was concluded that injectable trace minerals before estrus synchronization in Awassi sheep fed a balanced ration in terms of vitamins and minerals could not statistically significantly affect serum trace mineral levels during the application and removal of intravaginal sponges and reproductive parameters.