  (3 Sent)
Who saw this article? New!
Author: Neville J. Chandler
The following article is a special collaboration
from AFMA (Animal Feed Manufacturers Association) www.afma.co.za
We thank their kind support.
Feathers – The Raw Material
The American Association of Feed Control Officials (AAFCO) defines Hydrolysed
Poultry Feathers as the product resulting from the treatment under pressure of
clean, undecomposed feathers from slaughtered poultry, free of additives and or
accelerators. Not less than 75% of its crude protein content must be digestible
by the pepsin digestibility method.
There are over 1 million tonnes of feathers produced each year in the U.S. and
as the consumption of poultry meat increases so will the production of this valuable
raw material. Feathers have a protein content of around 84 percent and does not
suffer from the disadvantages of anti-nutritional factors, such as tannins, glucosinolates,
lectins and trypsin inhibiting factors. However raw feathers are relatively insoluble
and have a very low digestibility of five percent due to the high keratin content
and the strong disulphide bonding of the amino acids. Fortunately with the controlled
technology available to us today, we are able to convert a relatively insoluble
protein into a palatable and highly digestible protein source as seen in Table
1.
Table 1. Crude Protein content and Digestibility of various proteins.
| Protein |
C.P. % |
Ruminant Digestibility % |
Dig C.P. % |
Feather meal |
80.4 |
75 |
60.3 |
Fishmeal |
65.0 |
92 |
59.8 |
Meat & Bone |
50.2 |
86 |
43.2 |
Soybean Meal |
45.3 |
90 |
40.8 |
Rapeseed Meal |
35.9 |
84 |
30.1 |
Sunflower Meal |
30.1 |
85 |
25.6 |
Production of Feather Meal
Feather meal (FM) is produced from fresh feathers that are steam hydrolysed
under high pressure and temperature (140Ý C) for a period of time sufficient
to hydrolyse the chemical bonds of the feathers. Hydrolysing can be carried
out in batch cookers or continuos hydrolysers and is then followed by drying.
Different processing conditions such as time, temperature, pressure and moisture
can have an effect on the digestibility of the protein. Basically there is a
rapid increase in the time required for processing when the pressure drops below
207 kPa and a rapid fall in time as the pressure rises above 207 kPa. More recently
at least one company has proposed the use of enzymes as a ‘preconditioning
agent’ prior to processing in a pressure vessel. The aim of this process
is to increase amino acid availability and digestibility.
Feather meal produced under standard conditions from fresh feathers will have
the following approximate analysis, Table 2:
Table 2. Typical Analysis of Feather Meal – Ewing 1997
|
Dry Matter |
90% |
|
Crude Protein |
82% |
|
Digestibility |
75% min. |
|
Fat |
6% |
|
Ash |
4% |
|
Crude Fibre |
0.6% |
|
Available Lysine |
1.8% |
|
Methionine + Cysteine |
4.9% |
|
TMEn |
3.07 Kcal/g (12.8 MJ/kg) |
A note on the digestibility values. The official method for determining the
in vitro digestibility of feather meal is to use a 0.2% pepsin solution, however
recent research work has shown that if a 0.002% solution is used, then the values
obtained are more highly correlated with biological assays. The actual value
measured is lower than with 0.2% solution however the method appears to be more
sensitive and therefore of value in comparing one feather meal to another.
The Energy Value of Feather Meal
Initially work was carried out using broilers as it was considered that the
NRC values were too low. Upon investigation of the initial data, Pesti (1990),
found that when FM was included in diets at 40% of the ration then the energy
value was low, as the animals were unable to digest and absorb the amount of
protein offered. However when levels of 20% FM were added to the ration the
energy value was much higher than NRC published values (2.36 kcal/g)and it was
suggested that a value of 3.07 Kcal/g (12.8MJ/kg) was more appropriate. Similarly
Fuller & Dale 1986 found a TME value of 3.07 Kcal/g in feather meals being
used commercially in SE USA.
A prediction equation was formulated to predict the nitrogen corrected True
Metabolisable Energy:
TMEn (kcal/kg DM) = 2862 + 77(% fat)
The use of this formula showed that a feather meal with 7% fat had an ME value
46 percent higher than that reported by the NRC.
The Quality of Feather Meal Protein
Much of the direct work has been carried out with broilers and as these animals
are more sensitive to nutritional change. There is value in considering the
results since the feather protein that bypasses the rumen will be subjected
to the same digestion, absorption and utilisation that occurs in a broiler.
There is no doubt that in the 50’s and 60’s there was considerable
prejudice against feather meal as a result of its low and variable digestibility
which at that time was a reflection of the processing conditions. However, a
considerable amount of research was carried out at several U.S. universities,
(Fuller 1967, Naber et al. 1961, Summers 1969 and Thomas, 1972) which in effect
demonstrated that feather meal was a useful protein supplement for inclusion
in broiler diets. Corn – soya rations are equally deficient in methionine
and cystine. Fuller examined whether feather meal or fish meal could be the
sole source of animal protein in a corn soya diet. In order to determine how
much of the total sulphur amino acid (TSSA) needs could be met by cystine in
the feather meal, only enough methionine was added in each diet to keep the
TSAA content equal. There were no significant differences in body weight gain
or feed efficiency, demonstrating that at least half of the TSSA requirement
can be met with cystine and that feather meal is a good source of this amino
acid (Table 3).
Table 3. Feather Meal as a source of total sulphur amino acids.
(Fuller, 1967)
| Calculated Analysis |
Corn-Soya basal ration |
5% Fish meal |
5% Feather meal |
| ME (MJ/kg) |
12.72 |
12.72 |
12.71 |
| Protein % |
24.2 |
24.3 |
24.2 |
| Methionine added % |
0.1 |
0.04 |
0.075 |
| Methionine total % |
0.484 |
0.479 |
0.432 |
| Cystine % |
0.373 |
0.378 |
0.425 |
| Total Sulphur AA % |
0.857 |
0.857 |
0.857 |
| LWG (2-8 weeks) g |
1660 |
1687 |
1683 |
| FCR (feed/gain) |
2.25 |
2.20 |
2.24 |
Summers 1969 reported on the extent to which feather meal can be used in practical
broiler rations. The corn-soy and corn-soy-feather meal rations were calculated
to be equal in energy and protein. Feather meal protein replaced soy protein up
to the point where the first limiting amino acid became limiting in the diet.
Hence the starter diet contained 6% and the finisher diet 4.1% feather meal. No
differences were observed in growth or feed efficiency of chicks fed the two diets,
Table 4.
Treatment |
9 week weight (g) |
FCR |
Corn-soy
diet |
2077 |
2.27 |
Corn-soy-feather
diet |
2082 |
2.27 |
More recently Baler (1981) has demonstrated that as long as there was methionine
and lysine supplementation, up to 40% of the crude protein could be supplied
by feather meal without affecting growth or feed efficiency.
The data obtained with chicks indicates that upon absorption from the GI tract,
that the protein in feather meal can be well utilised. An interesting observation
from Cabel et al. (1986), was that when feather meal was included in rations
at a level of 4-6% for 7-14 days prior to slaughter, a significant reduction
in abdominal fat was observed, without affecting growth or FCR.
Amino Acid Availability
Liu et al. (1989) examined 3 samples of feather meal to determine true amino
acid availability (AAA). They found that true AAA ranged from 59.2 lysine to
82.8% arginine, with an overall mean of 72.3% (Table 5). Although these values
are lower than other studies they do compare well with studies by Nordheim &
Coon (1984).
Table 5. True Amino Acid Availability of feather meal (Liu et al 1989).
Amino Acid |
TAAA % |
| Lysine |
59.2 |
| Methionine |
74.4 |
| Methionine added % |
0.1 |
| Cystine |
64.2 |
| Leucine |
76.9 |
| Phenylalanine |
79.2 |
| Arginine |
82.8 |
| Overall Average |
73.2 +/- 2.4 |
Feather Meal in Ruminant Diets
Having established from monogastric studies that FM is a valuable protein source
in a post ruminal phase of digestion it would therefore be appropriate to investigate
the effect of feeding feather meal to the total ruminant. A substantial amount
of work with beef cattle has been conducted by Klopfenstein and his colleagues
at Nebraska University with dairy trials being conducted at a number of different
sites.
Dairy
Moderately producing dairy cattle have been able to obtain all of their protein
needs from the passage and subsequent digestion of bacterial and protozoal protein.
However with increased genetic merit and the need to produce more per cow, ways
have been sought to feed both the cow and the rumen microbial population. Since
the amount of bacterial protein produced is maximised, nutritionists have examined
the need to supply greater amounts of protein post-ruminally by using either chemically
treated or naturally occurring by-pass proteins. Rendered proteins are a source
of by-pass protein and in recent times the use of feather meal has been examined
in the diets of high producing dairy cattle.
Harris et al. (1997) examined the effect of three levels of feather meal on two
protein content diets (Table 6).
Table 6. Effect of various levels of FM
on dairy production
| |
|
14% |
Diet |
|
18% |
Diet |
| |
0% FM |
3% FM |
6% FM |
0% FM |
3% FM |
6% FM |
| DMI |
ns |
Ns |
ns |
ns |
ns |
ns |
| BWt Ý |
ns |
Ns |
ns |
ns |
ns |
ns |
| MF% |
ns |
Ns |
ns |
ns |
ns |
ns |
| MY |
0 |
++ |
+ |
0 |
0 |
0 |
| MP% |
0 |
- |
-- |
0 |
- |
-- |
They concluded that up to 6% FM had no negative effect on intake or body weight,
a positive effect upon milk yield at the lower protein diet and a linear negative
effect upon milk protein content. They suggested that the balance of amino acids,
low lysine and methionine, was inadequate for maximising milk protein synthesis.
Similarly Herbein and Webb (1997), found that 2.2% feather meal was not detrimental
to milk production or feed intake. However, the potential for feather meal to
increase milk components might be linked to the simultaneous feeding of other
high bypass proteins that have complimentary amino acid profiles such as blood
meal (BM) which provides more lysine and methionine. With the advent of protected
methionine supplements, these combined with low cost feather protein could prove
to be very economic for high producing dairy cattle.
Beef
Klopfenstein (1990) evaluated the protein value of urea, soy bean meal, FM, BM
and a 50:50 combination of FM and BM when fed to 260 kg calves for a 112 day period.
The basal diet was 50% ground corn cobs, 40% corn silage and 10% supplement and
supplied 11.5% crude protein and 57% TDN. The urea control calves gained 376 g/day
compared to BM alone which gave 735 g/day. The most efficiently used protein sources
were BM and FM:BM combination compared to soy bean meal and FM. The excellent
performance of the BM:FM combination was suggested as being due to the provision
of lysine in the BM.
Table 7. Protein efficiency* of various
sources of protein, measured in calves.
Ingredient |
Protein efficiency
|
| Blood
Meal (BM) |
2.92 |
| FM:BM
(50:50) |
2.62 |
| Feathe
Meal (FM) |
1.65 |
| Soy
Bean Meal |
1.21 |
- Protein efficiency measured by using the weight gain of the calves on the
urea diet as the base for comparing the weight gains obtained with the other
protein treatments. A high protein efficiency indicates that a protein source
is being converted more efficiently to Live Weight Gain compared to a protein
source that may have a low protein efficiency.
Conclusion
From monogastric studies we can see that feather meal has a high protein content
with a reasonable degree of digestibility. The amino acid composition of the
feather meal protein does require supplementation to balance out the low level
of lysine and methionine. When incorporated into ruminant diets consideration
needs to be given to the amino acid mix and supplement needs to be done, where
necessary. Based upon the price of feather meal, nutritionists should consider
more regular use of the commodity.
Neville J Chandler -- National
Renderers´ Association, 52 Packhorse Road,Gerrards Cross, Buckinghamshire
SL9 8 EF
References
Ewing, W.N. 1997 The Feeds Directory. Published by Context, UK.
Fuller, H.L. and N.M. Dale 1986. Proc 1986 Georgia Nutrition Conf., p98.
Fuller, H.L. 1967. Proc 1967 Georgia Nutrition Conf. p24.
Harris, B. Jr., Dorminey, D.E. and Van Horn, H.H. 1997 www.poultyegg.org/research/
Herbein, J.H. Jr. and Webb, K.E. Jr. 1997.>www.poultyegg.org/research/
Klopfenstein,T. 1990 Director’s Digest No 177: Fats & Protein Research
Foundation
Lui, J.K., Waibel, P.E. and Noll, S.L. 1989 Poultry Science 68:1513
Naber, E.C., Touchburn, S.P., Barnett, B.D. and Morgan, C.L. 1961.
Poultry Science 40:1234.
Nordheim, J.P. and Coon, C.N. 1984. Poultry Science 63:1040
Pesti, G.M., L.D. Faust, H.L. Fuller, H.M. Dale and F.H. Benhoff 1986
Poultry Sci. 65:2258
Pesti, G.M. 1990 Fats & Proteins Research Foundation, Directors Digest 172
Summers, J.D. 1969. Feedstuffs, March16. p.36.
Thomas, O.P., bossard, E.H., Nicjolson, J.L. and Twinning, P.V. Jr. 1972. Proc.
Maryland Nutrition Conf. p86.
Appendix 1: COMPARITIVE FEATHER MEAL
ANALYSES (as fed basis /kg product)
| |
NRA |
NRC |
INRA |
ACV |
MAAF |
| |
** |
(USA) |
(France) |
(Neth.) |
(UK) |
| Dry Matter % |
91 |
93 |
93 |
90.6 |
90.7 |
| POULTRY |
|
|
|
|
|
| ME broilers |
3240 |
2360 |
2800 |
3150 |
2968 |
| ME layers |
3240 |
- |
2800 |
3200 |
- |
| RUMINANT |
|
|
|
|
|
| TDN% |
70 |
65 |
- |
- |
- |
| ME kcal |
3350 |
2480 |
2892 |
- |
- |
| PIGS |
|
|
|
|
|
| TDN % |
66 |
62 |
- |
- |
- |
| DE kcal |
3730 |
2731 |
3730 |
- |
- |
| ME kcal |
3240 |
2215 |
3240 |
- |
- |
| CRUDE ANALYSIS |
|
|
|
|
|
| Crude Protein % |
83 |
84.9 |
85.8 |
85.7 |
80.9 |
| Fat % |
5.0 |
2.9 |
3.5 |
5.4 |
5.8 |
| Ash % |
3.0 |
3.5 |
3.17 |
2.1 |
2.3 |
| Crude Fibre % |
1.5 |
1.4 |
- |
0.0 |
4.3 |
| DCP % ruminants |
85 |
- |
86 |
86 |
- |
| DCP % pig |
85 |
- |
75 |
87 |
- |
| DCP % poultry |
75 |
- |
- |
77 |
- |
| MINERALS |
|
|
|
|
|
| Calcium % |
0.45 |
0.26 |
0.20 |
0.34 |
0.51 |
| Phosphorous % |
0.40 |
0.67 |
0.70 |
0.18 |
0.28 |
| Magnesium % |
0.15 |
0.20 |
0.18 |
0.20 |
0.03 |
| Potassium % |
0.20 |
0.29 |
0.24 |
0.15 |
0.14 |
| Sodium % |
0.20 |
0.70 |
- |
0.01 |
0.13 |
| Sulphur % |
1.50 |
1.50 |
0.90 |
- |
1.64 |
| Iron mg |
70.0 |
76.0 |
70.0 |
- |
61.00 |
| Manganese mg |
15.0 |
13.0 |
7.0 |
- |
18.00 |
| Selenium mg |
0.10 |
0.84 |
0.30 |
- |
0.07 |
| Zinc mg |
40.0 |
69.0 |
70.0 |
- |
13.80 |
| AMINO ACIDS |
|
|
|
|
|
| Lysine % |
1.85 |
2.32 |
1.84 |
1.63 |
1.82 |
| Methionine % |
0.55 |
0.55 |
0.53 |
0.60 |
0.55 |
| Cysteine % |
3.50 |
3.24 |
3.55 |
3.34 |
3.76 |
| Met + Cys % |
4.05 |
3.79 |
4.08 |
3.94 |
- |
| Threonine % |
4.00 |
3.97 |
3.91 |
4.20 |
4.10 |
| Tryptophan % |
0.50 |
0.52 |
0.43 |
0.51 |
- |
| Isoleucine % |
4.10 |
4.06 |
3.95 |
4.54 |
4.10 |
| Leucine % |
7.00 |
6.94 |
11.58 |
7.03 |
6.90 |
| Valine % |
5.00 |
3.06 |
6.88 |
7.20 |
6.30 |
| Histidine % |
0.75 |
0.99 |
0.58 |
0.51 |
1.20 |
| Arginine % |
6.00 |
7.05 |
5.66 |
5.91 |
5.39 |
| Glycine % |
6.50 |
6.44 |
- |
6.86 |
6.52 |
| Serine % |
10.0 |
9.26 |
- |
12.34 |
9.80 |
| Phenylalanine % |
4.00 |
3.05 |
- |
4.03 |
4.21 |
| Tyrosine % |
2.00 |
2.32 |
- |
- |
1.84 |
** NRA recommended values.
Author: Neville J. Chandler
(3 Sent)
Who saw this article? New!
MAKE A COMMENT ABOUT THIS ISSUE.
 
|
Technical Articles
