INFLUENCE OF BREEDING METHODS AND AGE OF DANISH SOWS ON THEIR PRODUCTIVITY
Authors: Povod M. G. , Mykhalko О. G. , Andreychuk V. F. 
Published: August 2021

The article compares the reproductive qualities of sows of Danish selection obtained by different breeding methods during their seven farrowings in one farm. It was found that local sows F1 obtained from mothers of Landrace breed and boars of Danish Large White breed had a significant excess of the total number of piglets at birth over analogs obtained by backcrossing of two-breed sows with boars of Danish Landrace breed by 0.90 head or 5.92 % (p<0,001). Both purebred sows of Danish Landrace and local sows significantly exceeded their peers obtained by the method of backcrossing by the number of stillborn piglets by 1.17 heads or 45.88% (p<0.001) and 0.5 heads or 26.60% (p<0.001) respectively. The probable lag of sows obtained by backcrossing in terms of the proportion of stillborn piglets from both purebred analogs by 5.03% (p<0.05) and from local analogs – by 9.29% (p<0.05). The complex indicator of reproductive qualities, calculated as an evaluation index, showed that the best such qualities were possessed by livestock for purebred breeding, where animals scored 0.05 and 0.74 points more than their peers F1 and Fr, respectively. The calculation of the estimated selection index of reproductive qualities of sows allowed to state that sows obtained from backcrossing had a higher value of 109.66 points, which is more than their purebred peers – by 4.48 points and local peers – by 3.96 points. According to the results of the first farrowing, a significant difference in the total number of piglets at birth, fertility, number of piglets at weaning, safety, nest weight at weaning, the weight of 1 head at weaning between livestock groups is not established but found that purebred sows relative to analogs obtained from backcrossing had a significantly higher number of stillborn piglets by 0.75 head or 60.00% (p<0.01) and the proportion of stillborn piglets by 5.09% (p<0.01). Evaluation of the data of the second, fourth, fifth and seventh farrowings revealed no significant difference in the bulk of the indicators of reproductive qualities of sows between the livestock of all groups. The study of the third farrowing allowed claiming that the number of stillborn piglets in this period was probably higher in sows of the first control group relative to analogs of the second experimental (F1) by 0.73 heads or 31.88% (p<0,05) and relative to analogs Experimental III (Fr) by 0.97 heads or 42.36% (p<0.01). According to the sixth farrowing piglets of the II experimental group (F1) exceeded the number of births by 1,77 heads or 12.46% (p<0.05) – control analogs, the fertility rate – by 2.32 heads or 19.66% (p<0.01) – analogs of the control and 1.41 head or 9.99% (p<0.05) – analogs of the III experimental group (Fr), but at the same time inferior in terms of safety to peers of the control group by 13.25% (p<0.01). Intergroup analysis of data showed that during the sixth farrowing piglets of the II experimental group (F1) exceeded the fertility rate – by 2.32 heads or 19.66% (p<0.01) – control analogs and 1.41 heads or 9.99% (p<0.05) – analogs of the III experimental group (Fr). The study of the dynamics of absolute, average daily, and relative growth of piglets revealed that both in the control group (purebred Danish Landrace) and in the third experimental group (Fr) in terms of seven farrowings, the indicators did not differ statistically. However, piglets of group II (F1) during the sixth farrowing had the highest values: the absolute increase was 6.18 kg, exceeding the first by 0.58 kg or 10.36% (p <0.05), the average daily gain – 221 g, which is higher than the average for the first farrowing in the group by 20 g or 10.50 % (p<0.05) and a relative increase of 138.62%, which is higher than the results of the first by 7.23% (p <0.01).