Impacts of feeding different nutrients and additives to pigs after weaning on diarrhoea

Transcription

1 SvineKongres 2018, Herning, Denmark Impacts of feeding different nutrients and additives to pigs after weaning on diarrhoea John Pluske School of Veterinary and Life Sciences AND Chief Scientist/CEO, APRIL

2 Outline of today s presentation 1. Current situation of the Australian pork industry 2. Diarrhoea after weaning - emphasis on protein and amino acids 3. Other nutritional considerations for diarrhoea 4. Perspectives

3 1. Current situation of the Australian pork industry Not fantastic

4 Australia average pig price versus average grain price, comparison AU c/kg carcass AU $/tonne 18.4 DKK/kg 1,840 DKK 13.8 DKK/kg 1,380 DKK 9.2 DKK/kg 920 DKK ($1 AU = ~4.6 DKK) (as of October 5, 2018)

5 Australia current grain price comparison (wheat, barley and sorghum) AU $/tonne 1,840 DKK 1,380 DKK 920 DKK ($1 AU = ~4.6 DKK) (as of October 5, 2018)

6 Estimated (average) cost of production (COP) (as of September, 2018) Carcass weight, kg * kg kg kg More than 85 kg Average price, AU $/kg Average price, DKK/kg Estimated COP, AU $/kg Estimated COP, DKK/kg $ DKK (Based on feed cost at AU $420/tonne and selling 23 pigs/sow/year) (* Top of weight range used)

7 Australia - Monthly pig slaughters (as of July, 2018); all pigs (Sources: APL, ABS) x 1,000 ~ 5% more pigs and 6% more meat than 2017 oversupply

8 Business and performance indicators for selected countries, (all AU $) (courtesy Dr. Roger Campbell; September 2018) AUSTRALIA New Zealand USA United Kingdom DENMARK COP (AU$/kg) Feed ($/tonne) Feed ($/tonne carcass weight) Other costs ($/t CW) % 12% 33% Herd feed conversion Pigs sold/sow/year Carcass weight, kg Carcass (kg) per sow per year Mortality after weaning (%) % 10% 50%

9 2. Examining nutrients after weaning: emphasis on protein and amino acids

10 Diarrhoea after weaning: compromised health of the gastrointestinal tract Infectious and non-infectious aetiology (risk factors) Infectious = pathogenic, e.g., bacteria, viruses, that cause diarrhoea, production losses, morbidity & mortality However, presence of pathogens does not mean pigs will succumb to clinical disease, ß-haemolytic E. coli found in both healthy and diarrhoeic piglets Weber et al. (2015; Denmark); No statistical association between numbers of pathogens and diarrhoea status Level of pathogen excretion identical between pigs with/without diarrhoea Non-infectious = environmental, management considerations May predispose pigs to infection and clinical disease

11 A major challenge: diarrhoea Pathogenic E. coli serotypes after weaning (F18), other pathogens, e.g., Lawsonia intracellularis, Brachyspira spp. (e.g., pilosicoli, hyodysenteriae); viruses Mixed infections can occur ~ days after weaning, often associated with e.g.,stress (moving, mixing), diet change, stopping medication treatment, Changes can cause episodes of diarrhoea - microbial origin or nutritional origin Current nutritional strategies effective for some pathogenic bacteria might not be effective or appropriate for other pathogenic bacteria

12 Overview of different feeding concepts to replace zinc oxide after weaning Concepts FRAmelco Trouw Nutrition Evonik Vitfoss Reduced protein Increased Threonine:Lysine Monoglycerides Organic acids Probiotics Fibre Additional enzymes Organic minerals Drinking water (courtesy Kjeldsen and Bache, SEGES PRC, 2018)

13 Total number of antibiotic treatments for diarrhoea (pigs with different feed concepts) Diet change Diet change (Complete removal of ZnO; 14 days) (courtesy Kjeldsen and Bache, SEGES PRC, 2018)

14 Lower protein diets after weaning Content of crude protein (CP), amino acids (AA), or both, influences formation and concentrations of compounds/metabolites, from bacterial metabolism Higher dietary CP levels can increase bacterial growth and metabolism, and increases production of osmotic and inflammatory compounds, in younger pigs Reducing dietary CP concentrations and balancing with synthetic essential AA can reduce formation of bacterial metabolites, and reduce diarrhoea However, performance of pigs should not be compromised as a result of feeding lower CP diets to enhance commercial adoption

15 Reducing protein supply to the hindgut reduces protein fermentation (14 d after weaning) Crude protein content, g per kg diet Item Statistics NH 3 -N, mg/l Yes Amines, mm Putrescine Yes Cadaverine No Acids, mm Isobutyric acid Yes Isovaleric acid Yes Total acids Yes (Htoo et al., 2007; J. Anim. Sci., 85: )

16 Ammonia content in the gut increases with more protein intake (7-21 d after weaning) Faecal ammonia nitrogen, mg/l Average daily protein intake, grams per day (Heo et al., 2015; An. Sci. J. 86: )

17 Feeding a lower protein diet without antimicrobials for only 5-7 days after weaning can reduce diarrhoea without affecting performance % pigs 30.0 HP LP5 LP7 LP10 LP Days after weaning 1-28 days after weaning HP = 243 g/kg (13.8 g Lys/kg) LP = 173 g/kg (12 g Lys/kg; + Val and Ile) Pigs then fed 215 g/kg diet (Heo et al., 2008; Arch. Anim. Nutr., 62: )

18 Apparent ileal digestibility varies with time after weaning and E. coli F4 (K88) diarrhoea Healthy pigs Sick pigs (E. coli) Day 7 Day 14 Day 7 Day 14 Crude protein Lysine Methionine Threonine Isoleucine Valine Average (AA) (Pigs fed 239 or 193 g crude protein/kg; 11.6 v 10.2 g Lys/kg) (Heo et al., 2010; Anim. Feed Sci. Technol. 160: )

19 Apparent and true protein digestibility in piglets fed milk replacer or weaner diet (pigs weaned 28 d; measurement at 35 d) Milk replacer Weaner diet % Higher digestibility = less protein into large intestine Apparent ileal digestibility True ileal digestibility (Kluess et al., 2010; Animal4: )

20 Flow of crude protein (CP; g/d) into hindgut affected by protein level, infection, and age Healthy pigs Sick pigs (E. coli) Day 7 Day 14 Day 7 Day 14 High CP (23o g/kg) Lower CP (190 g/kg) Summary: Higher protein diets cause greater flow on nitrogen into large intestine Pigs infected with E. coli have a greater flow of protein into large intestine Flow of protein into the large intestine increases with more time after weaning (Heo et al., 2010; Anim. Feed Sci. Technol. 160: )

21 Relationships between average daily protein intake (~21 d) and incidence of diarrhoea In E. coli-infected piglets, exceeding ~50-60 g protein/day worsens diarrhoea (Heo et al., 2015; An. Sci. J. 86: )

22 Nitrogen balance in pigs fed lower protein diets from ~ 3 weeks after weaning (10 20 kg) Item Crude protein level, g/kg Statistically significant? Digestibility, % No N retained, % of intake N retained, % of absorbed Yes Yes (Gloaguen et al., 2014; J. Anim. Sci. 92: )

23 Digestibility and nitrogen retention increase with age, allowing for greater use of free amino acids Item Exp. I: Cereals + soybean meal + free amino acids Exp. II: Cereals + free amino acids Protein level, % EAA:NEAA 46:54 46:54 49:51 53:47 46:54 42:58 SID % Lysine SID Lys:CP Start BW, kg End BW, kg ADG, g Gain:feed SID Lys:CP ratio not > ~6.9%; N or NEAA become limiting (Gloaguen et al., 2014; J. Anim. Sci. 92: )

24 Reducing protein reduces loose faeces and urine but has no affect on production (12-26 kg) Dietary CP level, % of diet Item % change (22.4 v 16.9%) BW, kg Start Final Consistency of feces (% of total number of days in the experiment): Soft % Liquid % Urine production (g/day) % (Le Bellego and Noblet, 2002; Livest Prod Sci. 76: 45 58)

25 Future considerations Examine different protein/aa levels in the second and third stages of growth, up until 30 kg body weight, Is there an intake cut-off point (g per day) in older pigs to reduce diarrhoea? Examine interactions between protein levels and other nutrients and dietary components, e.g., fibre, mineral levels Pathogen-specific nutritional interventions

26 3. What are some other possible nutritional considerations?

27 Lauric acid (dodecanoic acid): saturated fatty acid (12-carbon atom chain), having many properties of medium-chain fatty acids (MCFA) As a component of triglycerides (joined to glycerol), is ~ 50% of fatty acids in coconut milk and oil, laurel oil, and and palm kernel oil Experiments examining (i) lauric acid, (ii) monolaurin (glycerol monolaurate; a monoglyceride) addition to diets for late finishing swine (production, microbiome), and (iii) lauric acid and ileitis (infection) Antimicrobial (Gram positive) and growth promoting properties for swine?

28 Porcine proliferative enteritis (PPE), ileitis Agent = Lawsonia intracellularis

29 Pure lauric acid (20 g/kg) reduced number of Lawsonia excreted and sick pigs given antibiotic Item Lawsonia numbers (per g faeces); days after infection Day 7 Day 11 Day 14 Day 18 Day 21 Control g/kg lauric acid % reduction 11% 5% 6% 4% 9% Summary: No differences in faecalconsistency (looseness of faeces); also seen in other studies 20% of Control pigs treated (antibiotic) for severe diarrhoea, o% for lauric acid (Collins and Pluske, unpublished data)

30 Distillers dried grains with solubles (DDGS) In the US swine industry, DDGS is thought to help protect pigs against ileitis Rationale / perception is that any protective effect derives from its high insoluble fiber content (~ 43%), Effects of residual yeast from the fermentation cannot be discounted Several experiments conducted

31 Effects of DDGS (~ 3% extra fiber) with and without antibiotics on a Lawsonia challenge Treatment Negative control (no infection) Diet Antibiotics % pigs passing Lawsonia; 14 d after infection Corn-soybean meal No 0 Infected (control) Corn-soybean meal No 62 Infected + 10% DDGS Corn-soybean meal + DDGS No 23 Infected + antibiotics Corn-soybean meal Yes 23 Infected + 10% DDGS + antibiotics Corn-soybean meal + DDGS Yes 40 (Bacitracin Methylene Disalicylate (BMD ) and Chlortetracycline (Aureomycin )) (Whitney et al., 2006; J. Anim. Sci. 84: )

32 Gain to feed is similar feeding pure medium-chain fatty acids compared on G:F d to 0-14 antibiotic (14 d) ~ 1% in diet MCFA: different ratios C6:C8:C10 G:F G:F a 0.76 a 0.90 b 0.90 b ab ab Control CTC 1:1:1 MCFA 0.82 ab ab, P < 0.05 Product A 0.90 b Product B Control CTC 1:1:1 MCFA Product A Product B Cochrane et al.,

33 4. Perspectives Emphasis on reducing protein intake in first days after weaning, but what are the impacts of feeding lower protein diets beyond 9 kg? But, protein is not the entire solution Promising feed additives and diet concepts for diarrhoea and growth, but limited by higher cost and require more research to develop the optimum solution(s) Greater precision needed in the diagnosis and administration of batch-delivered antibiotics to prevent/treat enteric infections Continued emphasis on vaccines, management influences, breeding