Table 1 – Impact of hydrothermal processing on gastro-intestinal physiology in pigs.
Body weight range in kg 50-100 5-100
References are available on request.
Processing, main cereal Pelleting, corn Pelleting, corn
Effects (processed vs mash) Increased stomach keratosis Increased stomach ulcers
Feed processing parameters can influence the pigs’ gastro- intestinal health.
composition and/or metabolic activities) in the gastrointesti- nal tract of pigs. According to data in the literature, reducing the quantity of fine particles in pig feed is strongly recom- mended. Generally, based on existing literature the quantity of finer particles (<0.4 mm) should be as low as possible due to the negative effect on gastrointestinal tract health, and the quantity of the coarsest fractions (>1.6 mm) should also be low due to reduced nutrient utilisation. The proportion of medium-sized particles (>0.5 to <1.6 mm), which are consid- ered optimal for the pig’s digestive system, should be as high as possible.
Benefits are beyond doubt The benefits of feed processing in terms of animal perfor- mance and economics are beyond doubt. However, with evolving pig production practices, the regimens for feed processing will no longer be appreciated only in terms of optimising nutrient utilisation, but also in terms of their impact on feed hygienic status, the efficacy of feed additives, animal health and food safety. Feed processing should take into consideration an increasing focus on dietary approaches (ingredients and physical characteristics) for maintaining a healthy and functional gastrointestinal tract. Understand- ing the mechanisms involved in the complex interactions between the diet, intestinal microbiota and intestinal tissue can assist in supporting gastrointestinal tract function and health via targeted modifications of the diet. Optimal par- ticle size could be designed in the grinding process using a roller or hammer mill. However, since most pigs are fed diets subjected to hydro- thermal processing, additional reduction of feed particle size is inevitable. Because fine grinding is generally favoured for high pellet quality, and because it is difficult to avoid further
reduction in feed particle size during the pelleting process, fine particle size will almost inevitably be found in pelleted feeds. The options to reduce the intensity of grinding of particles during pelleting, by varying the parameters of the pelleting process, are very limited. A modified extrusion process (i.e. processing using an expander) followed by a shaping ele- ment as applied in the pet industry could be an alternative for pelleting to preserve particle size. Strategies such as adding concentrated fibrous material may be more suit- able in pelleted feed, but data are largely lacking as to its applicability in practical diets.
This article is edited from the original paper: Role of Feed Pro- cessing on Gut Health and Function in Pigs and Poultry: Conun- drum of Optimal Particle Size and Hydrothermal Regimens, published in Frontiers in Veterinary Science (2019,6:19).
Table 2 – Impact of feed particle size on gastro- intestinal physiology in pigs.
Body weight range in kg Particle size range, cereal Effects (larger vs smaller) 5-18.0
0.30-0.90mm, corn, hard sorghum
5-18.0
50-100 30-60
60-90 5-100
0.40-1.00mm, corn 0.43-1.10mm, barley
Reduced stomach ulcerations. No effects on intestinal histomorphology
0.30-0.90mm, soft sorghum Reduced stomach ulcerations. No effects on small intestine histomorphology Reduced stomach keratosis
0.40-1.30mm, wheat 0.50-1.25mm, corn
References are available on request. ▶ PIG PROGRESS | Volume 38, No. 3, 2022 53
Reduced stomach ulcerations. No effect on small intestine histomorphology Reduced stomach ulcerations Reduced stomach ulcers
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68
