Change of an index of reproductive characteristics of a sow depending on age

Work goal: the analysis of change of an index of reproductive characteristics of a sow depending on age. For achievement of this goal, raise the following objektives: 1) to estimate change of reproductive characteristics of investigated sows from the first to the last farrows; 2) to calculate indexes (R) reproductive characteristics for each sow, separately on everyone farrow; 3) to estimate index change (R) reproductive characteristics at number increase farrow. The work has been executed in 2008 in the enterprise of pigs of the Kaunas area. It was made 14 groups of sows of breed landrace. Test sows were from first to seventh farrows. The analysis of a reproduction and calculations of an index of a reproduction are executed on everyone farrow (from 1 to 7). For an estimation of efficiency and a reproduction index were analyzed the following indicators: 1. Fertility of sows, in units; 2. Quantity of piglets 21 days old, in units; 3. Weight of nest of piglets 21 days old, in kilo; 4. Quantity of piglets at weaning, in units; 5. Weight of nest of piglets at weaning, in kilo. The analysis of the sow's fertility changes, depending on the quantity of farrows, found that the fertility increased from the first farrow. The lowest fertility was at first pigs sow – 9.93 piglets, the highest fertility was found during the fourth farrow – 10.63 units or 0.70 piglets more that the first farrow. From the fourth farrow was found the tendency of reduction of fertility, i.e. fertility of the fifth farrow was 0.06 units, sixth – 0.13 units and seventh – 0.30 inits lower than the fourth farrow. Quantity of piglets 21 days old and at weaning, the fourth farrows were also the largest - accordingly on 9.25 piglets. These indicators had a tendency to increase from the first farrow, and from the fourth - to decrease. Worst results were during at the seventh farrows time, i.e. quantity of piglets 21 days old and at weaning was on 7.33 piglets, or 1.92 piglets less that the fourth farrow. The analysis of the sow's milkiness (weight of nest of piglets 21 days old) changes, depending on farrows, found that more milkiness was a first pig sows – 54.71 kilo. By the third farrow, sow milkiness was similar level, while the fourth farrows found a marked reduction tendency. The lowest milkiness was the seventh farrow sows – 39.33 kilo, or 14.21 kilo (p< 0,05) less that the third farrow and 15.38 kilo (p< 0,05) less that the first. The largest weight of weaning nest was found of the third farrow sows – 82.00 kilo, or 4.14 kilo more that the first pig sow. From the third farrow the weight of weaning nest also had a tendency to reduction. The lowest weight of weaning nest was found of the seventh farrow sows – 66.33 kilo or 15.67 kilo less that the third farrow. On the basis of the average data of each farrow, it was calculated the index (R) of reproductive characteristics. From the first to the fourth farrow (except the second) the reproduction index increased. The index of reproduction of the fourth farrow was the highest 36.99, or 1.36 units more that the first farrow. From the fourth farrow the reproduction index decreased. By the seventh farrow, it was lowest – 31.17, or 5.82 units less that the fourth farrow and 4.46 units less that the first farrow. On the basis on the received results it is possible to do following conclusions: 1. Fertility of sows of the fourth farrow, quantity of piglets 21 days old and at weaning was the highest: accordingly 0.70; 0.39 and 0.46 piglets more that the first farrow. 2. The largest weight of weaning nest was found of the third farrow sows – 82.00 kilo, or 4.14 kilo more that the first pig sow. 3. Value of an index of reproductive in regular intervals reflected changes of indicators of each farrow: more the best signs of value having farrows have been estimated by the best index of a reproduction – 36.99 of the fourth farrow sows. 4. The index of reproductive, as the main of reproductive characteristics rates, increased until the fourth farrow, and then began to steady decreased. Also it is possible to present such offers: 1. Based on the regularity of change of indications of reproductive characteristics, in a prominent decrease in the level of the fifth farrow, advisable in the pig enterprises, in the reproductive sector sows kept up to the fifth farrow. 2. More than five farrow sows in a herd to keep only considering of their productivity and health status