Optimizing an AI boar feeding program based on backfat measurements

4. Optimizing an AI boar feeding program based on backfat measurements

12. Innovation: Big Quill AI Feeding Grid

14. Location: Big Quill Boar Stud, Big Sky Farms, Quill Lake, SK

21. Name: Tanya Anderson, B.S.A.

22. Contact Information:

23. Box 3643

24. Humboldt, SK

25. Ph. (306) 682-9925

26. Wk. (306) 682-5041

27. tanderson@bigsky.sk.ca

29. Nominator: John Harding, D.V.M., MSc

30. Contact Information:

31. Ph: (306)682-2747

32. harding_hsvs@qlo.com

33. Optimizing an AI boar feeding program based on backfat measurements

35. Introduction

36. Using the Renco Lean-meater digital backfat indicator, we have designed a feeding grid to allow AI stud staff to customize feeding based on the backfat levels of individual boars.

38. Research indicates that high-quality rations fed at appropriate levels will lead to improved boar performance (Dalrymple, 1994). In January 2002, Big Sky Farms built a 100-head boar stud to provide semen for our multiplication and commercial units. With little experience feeding adult boars, it was a challenge to design feeding guidelines for this unit and overfeeding was a major concern.

40. Innovation

41. Based on the digestible energy level in the boar diet and the metabolizable energy requirements for AI boars (Kemp and Soede, 1991), we are able to calculate daily feed allocation using a factorial approach (Table 1). We increased the ME required for maintenance by 20% due to the damp, cool conditions in the boar stud, and some wastage. In order to make the program more user-friendly for the AI stud staff, feed allocation is rounded to the nearest ½ lb. The feeding grid also calculates the daily intake of total and digestible lysine to ensure that we have no deficiencies or excesses. The nutrient specifications will be updated to reflect diet changes.

43. In order to achieve accurate data, backfat levels are measured quarterly or more frequently as required. For example, when new boars enter the system it is essential that we determine the amount of feed necessary to achieve optimum body condition. Measurements are taken at the last rib, 6.5 cm from the midline using the Renco Lean-meater. In order to achieve more accurate data, readings are taken from both sides of the animal and averaged. Boar weight is estimated visually by the AI stud staff as no scale is available at Big Quill. Using backfat level and the estimated weight of the boar, staff is able to determine feed allocation, according to the grid. The backfat level is recorded on the Boar Card so that the staff can make a quick reference to the feeding grid.

45. Discussion and Implications

46. The ideal backfat level is between 17-18 mm. Backfat levels of 14 to 15 mm require a 25% increase in feed and a backfat level of less than 14 mm requires a 50% increase in feed allocation. Backfat levels exceeding 20 mm will result in a 10% decrease in feed allocation, compared to baseline.

47. In addition, with the grid completed it was evident that the current diet had excessive lysine levels, compared to the target lysine level of 18 grams of total lysine per day(Kemp and Soede, 1991). Based on the feeding levels outlined in the grid the lysine level was reduced from 0.75% to 0.70% in the diet in order to reach that target. By eliminating the excess lysine in our ration we will reduce feed costs by an additional $204.17 annually (Table 2). Once again the diet cost is subject to change based on the price and availability of feed ingredients. The annual savings achieved by implementing the Big Quill Feeding Grid is $1127.87 per year

50. Table 2. Annual Savings of Feed Grid Implementation Feed Grid $923.70 Reduced Lysine Levels $204.17 Total Savings per year $1127.87