Pig International - January/February 2017 - 25

PigInternational ❙ 25
Although very fine particle size offers nutrient
digestibility advantages, health and feed logistics
concerns force us to use a much coarser particle size.

prefer to use the Pfost and Headley equations (Pfost,
H. and V. Headley, 1976, Methods of determining and
expressing particle size):
dgw= log-1[Σ(Wi log di)/ΣWi]
Sgw= log-1[ΣWi (log di-log dgw)2/ΣWi]0.5
Wi = weight fraction at the sieve
i and di = geometric mean diameter (dodu)0.5
du= geometric mean diameter of the sieve holes
through which the feed was passed and the following
sieve which the feed was withheld (do)

Adam Witczak | Dreamstime.com

Not all types of grains require
the same approach
Although the basic principles in terms of optimizing the grinding process are the same for every ingredient processed and can be summarized to the motto
"grinding should produce a uniform feed size and
optimal particle size distribution," not all raw materials
should be treated the same way.
Plenty of literature and field trials demonstrate
that grains rich in fiber like barley can significantly
improve their feeding value when more finely grinded.
January/February 2017 ❙ www.WATTAgNet.com

The consensus of research data suggests sizes of below
700 microns for ideal feed utilization and daily gain
for fiber rich raw materials.
On the other hand, other cereal grains rich in proteins such as soft and hard wheat, which tend to become
floury when excessively ground, should be differently
processed targeting a coarser size of 800-850 microns.

Read more: Measuring feed fineness
by sieving, www.WATTAgNet.com/
articles/4826

Particle size and pig performance
Pig performance is associated with many factors
related to feed such as type and quality of grains, feed
manufacturing process, heat processing (hydrothermal
or other) and grinding equipment (hammer mill screen,
tip speed, etc.). It is well-accepted that within reason
and not at the extreme that the finer the feed is, the better the performance for the finishing pigs. But what we
also have to remember is that in addition to the particle


http://www.WATTAgNet.com/articles/4826 http://www.WATTAgNet.com/articles/4826 http://www.Dreamstime.com http://www.WATTAgNet.com

Table of Contents for the Digital Edition of Pig International - January/February 2017

Pig International - January/february 2017
Contents
Managing livestock antibiotic resistance with diagnostics
How to quantify health status in farm animals
6 major piglet diarrhea causes and their management
Boosting piglet immunity with colostrum
Practical grinding guidelines for pig feeds
How to train gilts for electronic sow feeding systems
Fermented liquid pig feed benefits outweigh drawbacks
5 new smart farming pig products from EuroTier
VIV Asia 2017 to represent entire animal protein chain
Pigs and Money
Industry Happenings
Products
Marketplace
Pig International - January/February 2017 - Pig International - January/february 2017
Pig International - January/February 2017 - Cover2
Pig International - January/February 2017 - Contents
Pig International - January/February 2017 - Pigs and Money
Pig International - January/February 2017 - Industry Happenings
Pig International - January/February 2017 - 5 new smart farming pig products from EuroTier
Pig International - January/February 2017 - 5
Pig International - January/February 2017 - 6
Pig International - January/February 2017 - 7
Pig International - January/February 2017 - 8
Pig International - January/February 2017 - 9
Pig International - January/February 2017 - Managing livestock antibiotic resistance with diagnostics
Pig International - January/February 2017 - 11
Pig International - January/February 2017 - 12
Pig International - January/February 2017 - 13
Pig International - January/February 2017 - How to quantify health status in farm animals
Pig International - January/February 2017 - 15
Pig International - January/February 2017 - 6 major piglet diarrhea causes and their management
Pig International - January/February 2017 - 17
Pig International - January/February 2017 - Boosting piglet immunity with colostrum
Pig International - January/February 2017 - 19
Pig International - January/February 2017 - 20
Pig International - January/February 2017 - 21
Pig International - January/February 2017 - 22
Pig International - January/February 2017 - VIV Asia 2017 to represent entire animal protein chain
Pig International - January/February 2017 - Practical grinding guidelines for pig feeds
Pig International - January/February 2017 - 25
Pig International - January/February 2017 - 26
Pig International - January/February 2017 - 27
Pig International - January/February 2017 - How to train gilts for electronic sow feeding systems
Pig International - January/February 2017 - 29
Pig International - January/February 2017 - 30
Pig International - January/February 2017 - 31
Pig International - January/February 2017 - Fermented liquid pig feed benefits outweigh drawbacks
Pig International - January/February 2017 - 33
Pig International - January/February 2017 - 34
Pig International - January/February 2017 - Products
Pig International - January/February 2017 - Marketplace
Pig International - January/February 2017 - Cover3
Pig International - January/February 2017 - Cover4
http://www.piginternational-digital.com/201711
http://www.piginternational-digital.com/201710
http://www.piginternational-digital.com/201709
http://www.piginternational-digital.com/201707
http://www.piginternational-digital.com/201705
http://www.piginternational-digital.com/201703
http://www.piginternational-digital.com/201701
http://www.piginternational-digital.com/201611
http://www.piginternational-digital.com/201610
http://www.nxtbook.com/nxtbooks/watt/pigi_201609
http://www.piginternational-digital.com/201607
http://www.piginternational-digital.com/201605
http://www.piginternational-digital.com/201603
http://www.piginternational-digital.com/201601
http://www.piginternational-digital.com/201511
http://www.piginternational-digital.com/201510
http://www.nxtbook.com/nxtbooks/watt/pigi_201509
http://www.piginternational-digital.com/201507
http://www.piginternational-digital.com/201505
http://www.piginternational-digital.com/201503
http://www.piginternational-digital.com/201501
http://www.piginternational-digital.com/201411
http://www.piginternational-digital.com/201410
http://www.piginternational-digital.com/201409
http://www.piginternational-digital.com/201407
http://www.piginternational-digital.com/201405
http://www.piginternational-digital.com/201403
http://www.piginternational-digital.com/201401
http://www.nxtbook.com/nxtbooks/watt/pigi_201311
http://www.piginternational-digital.com/201310
http://www.piginternational-digital.com/201309
http://www.piginternational-digital.com/201307
http://www.piginternational-digital.com/201305
http://www.piginternational-digital.com/201303
http://www.piginternational-digital.com/201301
http://www.piginternational-digital.com/201211
http://www.piginternational-digital.com/201210
http://www.piginternational-digital.com/201209
http://www.piginternational-digital.com/201207
http://www.piginternational-digital.com/201205
http://www.piginternational-digital.com/201203
http://www.piginternational-digital.com/201201
http://www.nxtbookMEDIA.com