Copper and zinc in diets of growing pigs

Transcription

1 Copper and zinc in diets of growing pigs New insights in requirements Paul Bikker and Age Jongbloed

2 Outline Introduction Copper and zinc as essential trace element Present: recommendations, allowance and practice Two studies into zinc and copper requirements Objectives Experimental design Results and discussion Conclusions Practical implications

3 Copper and Zinc as essential trace elements Numerous physiological functions of zinc and copper Component of >200 metalloenzymes Zn, required for DNA transcription (zinc fingers) almost all metabolic processes depend on zinc Cu, red blood cells, iron metabolism, anti-oxidant Consequences of Cu and Zn-deprivation Loss of appetite reduced growth rate (Zn) Skin abnormalities (parakeratosis, thickening, lesions) (Zn) Bone development, growth, reproduction (Cu, Zn) Cu-deprivation only after experimental induction

4 Cu and Zn: recommendations in mg/kg Source Zinc Copper Weaned pigs BSAS, GfE, NRC, INRA, GF pigs BSAS, GfE, NRC, INRA,

5 Zinc and copper allowance, max. levels Zinc Copper EC PDV EC 2004 EC EC total content, PDV added via premix From ingredients: mg Zn, 5-8 mg Cu per kg PDV EC 2004 Pigs < 12 wk Pigs wk Pigs >16 wk Breeding pigs

6 Zinc in Complete feed for Pigs C onte nt (m g/k g) Num ber of sam ples limit Avg Median 90per Number trend avg y= 3.6x + 96 R 2 = 0.72 N = 1228 Adamse et al., 2011

7 Intermediate conclusions 200 Copper in Compleet feed for Piglets (< 12 wk) 45 Content (mg/kg) Number of samples limit Avg Median 90per Number trend avg y= 0.5x R 2 = 0.01 N = 211 Adamse et al., 2011

8 Adamse et al., 2011

9 Copper and zinc balance BW, kg Cu, mg/kg Zn, mg/k g Cu, g Zn, g Nursery GF-pigs Retention Excretion Excretion, % Not included Grower diet 2 wk Grower diet 4 wk

10 Intermediate conclusions Recommendations poorly documented and applied Dietary copper and zinc levels close to EC maximum >90% excretion in manure Aim: reduction in excretion without loss of animal performance and health Required: reliable recommendations for practical use Assumption: highest requirements in weaned piglets

11 Experimental objectives Effect of dietary zinc and copper levels on performance and health in young growing pigs Zinc and copper requirements Nutrient digestibility Effect of microbial phytase Effect of organic acid inclusion (only zinc) Effect of growth promoting level of copper

12 Experiment zinc, treatments Treatment Added Zn mg/kg Total Zn Analysed Zn Phytase FTU/kg Lactic acid, % Cu, added 160 mg/kg Phytase, analysed, 300 (intrinsic) and 1100 FTU/kg

13 Experiment zinc, design 720 weaned piglets, females and castrates 8 Treatments x 10 pens x 9 piglets 2 wk adaptation / depletion, low zinc diet (+10 ppm) 1 piglet sacrificed or excluded from each pen 6 wk main period: d post weaning Water and feed ad libitum Practical diets, adequate nutrient levels Digestibility in 6 replicates

14 Experiment zinc, observations D14, 28, 42, 56: body weight, feed intake D34, 55: faecal samples digestibility D0, 14, 35, 56: blood samples ALP, Zn, Cu D14, 56: body tissues liver, bone tissue Daily: health, medical treatments, losses 3x / wk: faecal consistency D56: score of skin and legs

15 Results zinc, faecal consistency Piglets with soft faeces: wk 1 20% wk 6 <1% No effects of dietary treatments Zn, Phy, LA Note dietary treatments in wk 3-8 post weaning No obvious effects of low zinc in prestarter diet (10 ppm)

16 Results zinc, health T 1 T 2 T 3 T 4 T 5 T 6 P- value 1 Added Zn, mg/kg Piglets, n Skin lesions - Light, n 28 b 0 a 2 a 1 a 0 a 1 a < Severe, n 16 b 0 a 0 a 0 a 0 a 0 a <0.001 Lesions of legs - Light, n 25 b 0 a 0 a 0 a 0 a 0 a < Severe, n 24 b 0 a 0 a 0 a 0 a 0 a <0.001

17 Results zinc, feed intake

18 Results, body gain

19 Results zinc, body weight (BW) and homogeneity Added Zn (mg/kg) T 1 T 2 T 3 T 4 T 5 T 6 P-value Model BW d 56, kg 32.7 a 39.5 b 39.8 b 39.7 b 39.9 b 39.5 b <0.001 SD BW d 56, kg 6.13 b 3.73 a 3.61 a 3.23 a 4.10 a 3.49 a <0.001

20 Results, feed conversion ratio

21 Results, serum alkaline phosphatase

22 Results, serum zinc concentration

23 Results, liver and bone zinc content

24 Results of phytase on digestibility (%) T 2 T 7 T 8 SEM 1 P- value 2 Phytase No Yes Yes Model Organic acid Yes Yes No Mean Ca 47.8 a 59.1 b 57.2 b 0.77 *** P 52.8 a 64.2 b 63.5 b 0.77 *** Cu -9.2 a -3.7 b -2.9 b 1.48 * Zn 0.9 a 10.1 b 15.2 c 1.18 ***

25 Estimates of zinc requirements Characteristic Linear-plateau max. breakpoint Performance ADG, g/d 676 ± ± 1.5 FI, g/d 1119 ± ± 1.5 FCR 1.65 ± ± 2.5 Blood serum ALP D35, U/L 202 ± ± 2.6 Zinc D35, µmol/l 12.6 ± ± 2.6 ALP D56, U/l 169 ± ± 2.1 Zinc D56, µmol/l 12.3 ± ± 2.7 Liver, mg/kg Zinc in DM 167 ± ± 8.5

26 Conclusions zinc Zinc requirements No added zinc: reduced intake and severe clinical signs of deficiency mg/kg adequate for body gain and health mg/kg adequate for blood parameters Substantial contribution of phytase to Zn supply No added value of organic acid inclusion

27 Experiment copper, treatments Treatment Added Cu mg/kg Total Cu mg/kg Analysed Cu mg/kg Phytase FTU/kg Zn, added 45 mg/kg, analysed Phytase, analysed, 165 (intrinsic) and 760 FTU/kg

28 Experiment copper, design 640 weaned piglets, females and castrates 8 Treatments x 10 pens x 8 piglets No depletion period 2 wk prestarter, 6 wk starter diets 8 wk experimental period: 1-56 d post weaning Water and feed ad libitum Practical diets, adequate nutrient levels Digestibility in 6 replicates

29 Experiment copper, observations D0, 14, 28, 42, 56: body weight, feed intake D27, 55: faecal samples digestibility D0, 28, 56: blood samples Zn, Cu, Hb, Ht D0, 56: body tissues liver, bile Daily: health, medical treatments, losses 3x / wk: faecal consistency D56: score of skin and legs

30 Results, feed intake

31 Results, body gain

32 Results copper, feed conversion ratio

33 Results copper in liver and bile

34 Effect of phytase on nutrient digestibility (%) T 1 - T FTU SEM P-value DM Ca P Cu <0.001 Zn <0.001

35 Effect of high copper on growth performance T mg T mg SEM P-value BW D56, kg <0.001 SD BW D56, kg ADG, g/d <0.001 FI, kg/d <0.001 FCR

36 Effect of high copper, T 7 as % of T1-6

37 Effect of phytase on tissue levels T 1 - mg T FTU SEM P-value Day 28 Copper, µmol/l Zinc, µmol/l <0.001 Day 56 Copper, µmol/l Zinc, µmol/l <0.001 Liver, mg/kg DM Bile, mg/l

38 Effect of high copper on tissue levels T mg T mg SEM P-value Day 28 Copper, µmol/l Zinc, µmol/l Day 56 Copper, µmol/l Zinc, µmol/l Liver, mg/kg DM <0.001 Bile, mg/l <0.001

39 Effect of high copper (T7) on faecal consistency

40 Effects (ns) of withdrawal of high copper, T 7 (160/15) as % of T 5 (12/15 mg/kg)

41 Conclusions copper Copper requirements No effect of added copper on growth performance 7 mg/kg adequate for body gain and health 7-10 mg/kg adequate for blood parameters No consistent effect of phytase on copper supply Substantial effect of 160 mg Cu on growth performance and faecal consistency Numerical reduction in growth performance after withdrawal of high copper level

42 Copper and zinc balance, implications BW, kg Cu, mg/kg Zn, mg/kg Cu, g Zn, g Nursery GF-pigs Retention Excretion Excretion, % Reduction, % 41% Not included Grower diet 2 wk Grower diet 4 wk

43 Implications Reduction of zinc to 80 mg/kg 244 tons lower Zn excretion 30% reduction of annual accumulation Further reduction possible taking into account the phytase contribution More insight required in growth promoting effect of Cu; level, duration, withdrawal Validation of low copper content in GF pig diets

44 Copper in diet and liver (Jondreville et al., 2002)

45 Copper and zinc balance, future challenge? BW, kg Cu, mg/kg Zn, mg/kg Cu, g Zn, g Nursery GF-pigs Retention Excretion Excretion, % Reduction, % 24% 65% Not included Grower diet 2 wk Grower diet 4 wk

46 Acknowledgements We highly appreciate The financial contribution of the Product Board Animal Feed (PDV) and the Ministry of Economic Affairs, Agriculture and Innovation (EL&I). The input of their representatives E.R. Deckers (EL&I), H. Boelrijk, M.C. Blok, A. Cazemier, M. Hessing, C.A. Makkink, J. Michels, and A. van Wesel (PDV) Co-operation with staff of VIC Sterksel

47 Thank you for your kind attention