Feathers make up 6-10% of a mature broiler chicken (Ajayi, 2014)
Feathers contain 83-87% crude protein (CP) (Tiwary and Gupta, 2012;
Ajayi, 2014). Hydrolysed feather meal (HFM) has low digestibility
leading to poor performance in poultry (Shiroma and Hongo, 1974).
Exogenous enzymes improve digestibility and nutrient availability of
poorly digestible materials (Kocher et al., 2002, Cowieson and Adeola,
2008), they can be used in targeted part production (Ajayi, 2015).
Keratin (the protein of feathers) can be hydrolyzed by keratinases
which are not produced by animals. CIBENZA DP100 is a commercial
protease feed enzyme that is believed to have keratinase activity.
Enzyme use in animal feeding can also lead to a reduction in the
nutrient level in diets and subsequent reduction of voided nutrients
(Oxenboll et al., 2011).
Protein feedstuffs are more expensive compared to other nutrient
feedstuffs (Ajayi and Iyayi, 2014).
A feeding trial was conducted to investigate the effect of feeding
hydrolysed feather meal (HFM) in low crude protein (CP) diets
supplemented with a protease (CIBENZA DP100)on performance
indices and carcass measures of broiler chickens.
Materials and methods
Two hundred and forty, day old broiler chickens were randomly
allotted to 8 treatment diets.
There were three replicates and 10 birds per replicate in a 2x2x3
HFM was fed at 0% and 2%, protease at 0g and 5g/kg diet and
the CP were 15.5%, 17.5% and 23% based on the matrix value of
the serine protease used.
Four diets had 23% CP, two of which contained 0% HFM, while
two contained 2% HFM; the remaining four diets all contained
HFM, two had 17.5% CP and the other two had 15.5% CP; all
with and without protease.
All birds were given feed and water ad libitum in deep litter pens
Body weight gain (BWG), feed intake (FI) and feed conversion
ratio (FCR); and carcass weights were assessed at 42days.
We thank N. C. Ugorji for farm assistance, D. F. Ajayi and
A. Oyedeji for assistance with sample collection. Protease
for this work was provided by Norgem Nigeria limited, a
subsidiary of Novus USA.
HFM significantly decreased BWG from 1083g to 896g/bird and FI from
1895g to 1404g/bird.
Protease significantly increased BWG from 872g to 1013g/bird The
interaction between HFM and protease improved BWG significantly but
had no effect on the FI and FCR.
Interaction between all variables significantly improved BWG of birds
fed inadequate CP diets.
HFM had a significant decreasing effect on the live weight and dressed
weight while protease significantly improved dressed percent from 72.5
to 74.1 while breast meat deposition is improved with protease
supplementation across treatments.
A two-way ANOVA of GLM procedure in SAS (2004) was employed for
data analysis and means separated by Tukeys (p<0.05).
Ajayi, H.I. and Iyayi, E.A.
Department of Animal Science and Animal Technology, FAAT, Benson Idahosa University Benin City, Edo state. Nigeria
Ajayi, H. I. 2015. Effect of protease supplementation on
performance and carcass weights of broiler chickens fed low
protein diets. Nigerian Journal of Agriculture, Food and
Environment Vol.11(1) 29-32
Ajayi, H. I. 2014. Ileal crude protein digestibility of feather meal
supplemented with protease in broiler chicks. PhD Thesis,
University of Ibadan, Ibadan. Nigeria.
Ajayi, H. I. and Iyayi, E. A. 2014. Ileal nutrient digestibility and
performance in broiler chickens fed graded levels of feather
meal. Ibadan Journal of Agricultural Research Vol.
Cowieson, A. J. and Adeola, O. 2008. Carbohydrases, Protease and
Phytase have an additive beneficial effect in nutritionally
marginal diets for broiler chicks. Poultry Science 1860-
Kocher, A. Choct, M. Porter, M. D. and Broz, J. 2002. Effects of
feed enzymes on nutritive value of soyabean meal fed to
broilers. Australian Journal of Agricultural Research
Oxenboll, K. M. Pontoppidan, K. and Fru-Nji, F. 2011. Use of a
protease in poultry feed offers promising environmental
benefits. International Journal of Poultry science
Tiwary, E. and Gupta, R. 2012. Rapid conversion of chicken feather
to feather meal using dimeric keratinase from Bacillus
licheniformis ER-15. Journal of Bioprocessing and
Biotechnology 2(4): 123.
Figure 1. Photograph of day old broiler
chickens in deep litter pens
Feeding Hydrolysed feather meal with a serine protease to broiler
chickens significantly improved weight gain and dressed percent.
Birds fed adequate CP diets containing HFM and protease performed
comparably to birds fed a normal diet without HFM and protease.
Birds fed 15.5% CP containing HFM and protease produced breast
meat comparable to birds fed the control diet.
Figure 2. Detail of treatment diets
For further information
Please contact the corresponding author:
email@example.com +234803 608 6864
Department of Animal Science and Animal Technology
Faculty of Agriculture and Agricultural Technology
Benson Idahosa University
Benin City, Edo state.
Performance and Carcass Weights of Broiler Chickens Fed Low Protein Diets Containing
Hydrolysed Feather Meal (HFM) With Protease Supplementation
Table 1: Performance indices of broiler chickens fed protease, different CP and
HFM levels (0-42days)
HFM 0 0 2 2 2 2 2 2
Protease 0 5 0 5 0 5 0 5
CP 23 23 23 23 17.5 17.5 15.5 15.5 SEM
BWG 1077.7a 1088.3a 848.7c 1115.3a 733.7d 862.3c 828.7c 989.3b 76.6
FI 1853.7c 1935.8c 1484.3b 1280.0a 1429.1b 1450.9b 1445.6b 1332.4ab 147.4
FCR 1.8cd 1.8cd 1.6bc 1.3a 1.9d 1.7c 1.6bc 1.5b 0.2
a,b,c Figures along the row with same superscript are not significantly different statistically. HFM= Hydrolysed Feather Meal, CP= Crude Protein,
BWG= Body weight Gain, FI= Feed Intake, FCR= Feed Conversion Ratio, SEM= Standard Error of Mean, (P= 0.05)
1 2 3 4 5 6 7 8
BWG of birds fed diet containing HFM with adequate CP and
supplemented with protease (treatment 4) performed best
1 2 3 4 5 6 7 8
Birds fed diet treatment 4 had best FCR
No. 1 2 3 4 5 6 7 8
HFM (%) 0 0 2 2 2 2 2 2
(g/kg) 0 5 0 5 0 5 0 5
CP (%) 23 23 23 23 17.5 17.5 15.5 15.5
+ve Control -ve Control 1 -ve Control 2 -ve Control 3
Table 2: Combined effect of protease supplementation, HFM inclusion and
different CP levels on carcass weights of broilers (0-42d)
Treatment 1 2 3 4 5 6 7 8 SEM
DP (%) 73.1a 74.3a 72.8b 74.2a 71.6b 73.4a 72.6b 74.7a 1.8
Breast (g) 171.6a 192.4a 155.9b 176.3a 136.2b 141.6b 143.3b 163.0a 32.7
Thigh (g) 100.4ab 109.3a 90.4ab 101.8a 70.9c 83.8bc 91.8ab 88.2b 17.2
Drumstick (g) 97.8ab 104.9a 90.5bc 106.8a 70.7d 72.1d 79.2cd 88.9bc 14
a,b,c Figures along a row with same superscript are not significantly different statistically. HFM= Hydrolysed Feather Meal,
DP= Dressed Percent, SEM= Standard Error of Mean, (P= 0.05)
1 2 3 4 5 6 7 8
Protease supplementation improved breastmeat deposition
1 2 3 4 5 6 7 8
Protease supplementation improved dressed
percent in all treatments