Nutrition
WHITE PAPER
Broiler starter feeds
Reaching the growth potential of newly hatched broilers relies on several factors such as feed, feeding strategy, housing and management. Feeding a starter feed with a high content of digestible protein is one important factor to reach the full growth potential. HAMLET PROTEIN has specifically created HP AviStart to meet the feeding requirements that young broilers have.
HAMLET PROTEIN
WHITE PAPER / Broiler Starter Feeds / 2
Importance of starter period Efficiency in broiler production has over the years improved and every day becomes more important as production periods become shorter (Knowles, 2008). From the 1970’s till today the production cycle has decreased from 60 days to approximately 34-42 days, which makes the starter period (from hatch to 10 days) even more important in broiler production (Figure 1).
Production cycle Starter period as a % of total broiler production cycle
1970's
Today
60 days
38 days
Figure 1. S tarter period as a % of total broiler production cycle. Importance of starter period (from hatch to 10 days), (Uni, 2014).
Young chick development and growth Chick growth and development take place at an incredible rate during the first week after hatching. The hatchling’s weight quadruples (Aviagen, 2014) as it develops the organs – heart, liver and digestive tract (Uni, 2006; van den Brand et al., 2010) – to support the development of muscles and bones. The development of the digestive tract is much faster than the rest of the body (Uni, 2006). Young chicks have a limited ability to thermoregulate, and the digestive tract and immune system are very immature at hatch (van den Brand et al., 2010). The immune system starts to develop during the embryonic phase and continues developing for the first weeks after hatching (Amit-Romach et al., 2004; Bigot et al., 2001). This means newly hatched chicks have a very low resistance to pathogenic bacteria and viruses in early life. Chicks have passive immunity through the amniotic fluid and yolk. During the first week post hatch, the microbiota change rapidly, while at the same time the risk of exposure to Salmonella and Campylobacter increases the risk of colonization of the gut (Amit-Romach et al., 2004). A sub-optimal feed will contribute to more challenges a chick has to overcome, and will force the chick to draw on its yolk as an energy source for immunity. Therefore, feeding a more optimal diet with highly digestible nutrients will save nutrients and energy towards other important functions like gut development and muscle growth in chicks. Many nutrients are necessary to assure proper growth. Due to the chick’s undeveloped digestive tract, however, the capacity to absorb nutrients is impaired. Ordinary diets cause the chick to draw on the immunoglobulins and unsaturated fatty acids in its yolk sack for energy rather than for development and immunity (Noy and Uni, 2010). On top of this, the time from hatch to first intake of feed in the hatchery can be as much as 36-48 hours (Noy and Uni, 2010) putting further strain on the chicks.
HAMLET PROTEIN
WHITE PAPER / Broiler Starter Feeds / 3
The digestive and nutritional requirements of young chicks are far different from the requirements of older broilers so using differentiated feeds in more feeding phases (e.g. starter, grower and finisher) is optimal. Broiler digestion Digestion and absorption of nutrients early in life depend primarily on pancreatic enzyme activity. Pancreatic enzymatic reserves (especially trypsin, chymotrypsin and amylase) are low at time of hatch (Bigot, 2001; Uni, 2006). Due to the low enzyme production and activity, the feed has to be highly bioavailable / easily digestible – otherwise a large proportion of the feed will pass undigested through the digestive tract and be excreted in the droppings (Noy and Uni, 2010). This feed specific endogenous loss is related to the undigested dry matter, fibre content and composition, level of anti-nutritional factors in the ingredient and feed processing and is also related to the age of broilers: young chicks are more sensitive and generally have the highest feed specific nitrogen (N) loss (Ravindran and Bryden, 1999; Adedokun et al., 2007), making the bioavailability of starter feed ingredients important. In other words, feed ingredient choices (highly digestible sources) for the starting period need to be aligned with the immature digestive processes of the bird else, a loss in growth potential or feed efficiency will be evident. In addition to feed specific N loss, due to low feedstuff digestibility, the chicks have an increased endogenous N loss due to excretion of digestive enzymes, shed epithelial cells and intestinal microbes in digesta (Nyachoti et al., 1997). This endogenous N loss represents a negative nutritional value (Rérat, 1978; Just et al., 1981) as only a part of the endogenous N is reabsorbed (Nasset, 1972; Ravindran and Bryden, 1999). The relevance of age on endogenous loss is demonstrated in a study finding that the relative endogenous loss in 5d old chicks was twice the loss in 15d or 20d old broilers, independent of feedstuff fed (Adedokun et al., 2007). As a consequence, protein digestibility is lower at d5 than in older broilers, so feeding highly digestible protein in the starter feed is even more important. A controlled digestibility trial shows that the ileal digestibility of HP AviStart (Feeding Trial FTB09GB, 2012, HAMLET PROTEIN), measured as the weighted average of all amino acids, was approximately 102% (Figure 2, replacing 10% soybean meal in 22 day old broilers), which indicates that the protein digestive capability is boosted by introducing HP AviStart – the whole diet is more easily digested. Similar values for protein and amino acids digestibility in broilers have been found for HP 300 (another product from HAMLET PROTEIN) (Feeding Trial FTB07GB, 2010, HAMLET PROTEIN).
HAMLET PROTEIN
WHITE PAPER / Broiler Starter Feeds / 4
Ileal digestibility, % 120 115
113
110 105
107
104
98
100
97
99
95
95
93
91
90 85 80 CP
Lys
Thr
Met
Ile
Leu
Val
Phe
His
Figure 2. Ileal digestibility of HP AviStart of crude protein (CP) and some selected amino acids (AA). (Feeding Trial FTB09GB, 2012, HAMLET PROTEIN).
Several factors influence ileal digestibility of protein in broilers, e.g. age of broilers and level of anti-nutritional factors. However, HP AviStart is found to be a very highly digestible protein rich ingredient.
HAMLET PROTEIN
WHITE PAPER / Broiler Starter Feeds / 5
Improved digestibility with HP AviStart A recent study from the University of New England, Australia (Iji & Swick, 2014 ; Feeding Trial FTB05GB, 2013, HAMLET PROTEIN) compared feeding either spray dried plasma protein or HP AviStart during the first 10 days in both maize and wheat based diets with the control being a soybean meal based diet. Broilers fed spray dried plasma improved average daily gain (ADG) during the starter period while for birds fed HP AviStart no difference in performance during the starter period was found. For both treatments, performance improved significantly at the end of the trial (day of slaughter: day 34). The way the two ingredients HP AviStart and plasma positively improved the overall performance, after only having been fed during the starter period, was found to be very different. For HP AviStart, the ileal protein digestibility at day 24 (2 weeks post-feeding a starter diet) was significantly higher (5-10% units) (Figure 3). For spray dried plasma protein, ileal digestibility of protein was found to be higher in the wheat based diets and lower in the maize based diets. At day 24 there was no difference in gut enzyme activity among diets.
Ileal CP digestibility, %
Maize Wheat
85
85
80
80
75
75
70
70
65
0.0%
2.5%
5%
HP AviStart Inclusion
10%
65
0.0%
0.5%
1.0%
2%
Blood Plasma Inclusion
Figure 3. Ileal digestibility of protein in soybean meal + maize and soybean meal + wheat based diets, in 24 day old broilers fed increasing levels of HP AviStart or blood plasma during the starter period (day 1-10). (Iji & Swick, 2014 ; Feeding Trial FTB05GB, 2013, HAMLET PROTEIN).
At day 24 higher villus/crept ratios were measured when HP AviStart was fed during the starter period, in contrast for birds on the spray dried plasma protein, where this was lower. An explanation for these differences could be that the immunoglobulins from plasma help passive immunity in the first days while HP Avistart affects intestinal development and likely endogenous losses leading to the improvements in performance observed.
In summary, how single ingredients fed during the starter period positively improve overall performance is ingredient specific, with spray dried plasma protein giving an improved performance during the starter period, while HP AviStart improved digestibility later in life (Iji and Swick, 2014).
HAMLET PROTEIN
WHITE PAPER / Broiler Starter Feeds / 6
HP AviStart early in life affects end weight The chemical composition of the diet, content of digestible amino acids, energy, minerals and vitamins, are nutritional factors that determine the bird’s development in the early period of life. The interaction of intestinal growth, digestive functions and diet is critical during the post hatch period (Uni and Ferket, 2004). Adequate protein availability in the starter phase is essential to increase muscle development in later phases (Uni and Ferket, 2004). Feeding a diet with highly digestible protein during the starter period has shown to improve performance later in life (Iji and Swick, 2014). Swidersky (2004) found feeding a highly digestible starter feed for a period as short as 4 days to significantly increase the end weight. This is the effect of feeding HP AviStart during the starter period as it is shown that gain and lower FCR (feed/gain) come after the starter period (Feeding trials FTB01GB, FTB02GB, FTB03GB, FTB04GB, HAMLET PROTEIN) (Figure 4).
FCR (feed/gain) 2.5
HP AviStart Inclusion 0%
2.3
5 %
2.1
10%
1.9 1.7 1.5 Trial 1
Trial 2
Trial 3
Trial 4
Site 1
Trial 4
Site 2
Trial 4
Trial 4
Site 3
Site 4
End weight, g HP AviStart Inclusion
3000
0%
2800
5% 10%
2600 2400 2200 2000
Trial 1
Trial 2
Trial 3
Trial 4
Site 1
Trial 4
Site 2
Trial 4
Trial 4
Site 3
Site 4
Figure 4. FCR and end weight (Feeding trials FTB01GB, FTB02GB, FTB03GB and FTB04GB, HAMLET PROTEIN).
The trials show that feeding HP AviStart early in life – in the starter feed – pays off as increased weight at slaughter and improved FCR (feed/gain).
HAMLET PROTEIN
WHITE PAPER / Broiler Starter Feeds / 7
HAMLET PROTEIN Broiler Calculator HP AviStart has been tested in several university and commercial trials and based on the results, a broiler calculator has been developed to pre-calculate the return on investment (ROI) in HP AviStart in starter feed (www.hamletprotein.com). Based on your cost and production data and market prices, a ROI is calculated (Figure 5). Because of the limited quantity of HP AviStart eaten by chicks, the higher cost for the first diet is usually compensated very well by the results, with ROI’s of 5-15, depending on the market prices etc.
HAMLET PROTEIN – Broiler Calculator
Figure 5. HAMLET PROTEIN broiler calculator – the easy tool to calculate your potential net profit (HAMLET PROTEIN).
Foot Pad Lesions Foot pad lesions (Figure 6) are often an issue in the broiler industry. However, the prevention of foot pad lesions needs to be addressed in young broilers (<20 days) (Personal communication, 2014), as the foot pads are more sensitive (thinner skin) in chicks than in older broilers. Foot pad lesions are due to foot pad dermatitis, and an increased risk of infections is found in broilers with lesions (de Jong and van Harn, 2012). Higher incidences of foot pad lesions are often associated with increases in litter moisture which can be associated with the mineral level of the diet (primarily K) as well as the caustic nature of excreta causing inflammation of the skin of the foot. Foot pad management is therefore a combination of several factors: ventilation, diet mineral formulation, manipulation of diet formulation to manage uric acid excretion and water intake. High losses of N from undigested protein in droppings can potentially contribute to problems with foot pad dermatitis (Francesch and Brufau, 2004; de Jong and van Harn, 2012). Feeding young broilers a starter diet with more highly digestible protein is hypothesized to help the underdeveloped digestive track to develop and lead to better digestion and lower N-loss in droppings later.
Figure 6. Left: No foot pad lesion. Right: Severe foot pad lesion, (Feeding Trial FTB06GB, 2014, HAMLET PROTEIN).
HAMLET PROTEIN
WHITE PAPER / Broiler Starter Feeds / 8
In a recent study (Feeding trial FTB06GB, 2014, HAMLET PROTEIN), HP AviStart was found to reduce foot pad lesion scores more than potato protein, fish meal and corn gluten, when all were fed at 5% during the starter period (Figure 7). It is common to use potato protein, fish meal and corn gluten as they all have a higher protein content and lower K content than soybean meal or HP AviStart. However, as noted below, HP AviStart resulted in improved foot pad lesion scores suggesting that HP AviStart’s improved N digestibility may be associated with improved foot pad lesion scores regardless of the K level in the diet.
Foot Pad lesion score 1.0 0.9 0.8
0 = no lesions
0.7
1 = small lesions
0.6
2 = affected skin
0.5
3 = lesions through the skin
0.4 Soybean meal
Potato protein
Fish meal
HP AviStart
Corn gluten
Figure 7. Average foot pad lesion score at day 42 in broilers fed starter diet with reference (soybean meal) or 5% of potato protein, fish meal, HP AviStart or corn gluten. (Feeding Trial FTB06GB, 2014, HAMLET PROTEIN).
These new results show that HP AviStart might offer an alternative to manage foot pad lesion in broilers.
HAMLET PROTEIN
WHITE PAPER / Broiler Starter Feeds / 9
Perspectives The value of feeding a highly digestible starter feed is found in several key elements in commercial broiler production – survival rate, uniformity during production, end weight and FCR (feed conversion ratio). All are highly related to the under-developed digestive tract (van den Brand et al., 2010; Noy and Uni, 2010). Together with the shorter production cycle, this implies great importance of and focus on the starter period and starter feeds now and going forward. The importance of using a highly digestible starter feed is also related to the increased focus on reducing the use of antibiotics (Castanon, 2007). Without the possibility of using antibiotics as a growth promoter, followed by the demand to bring down overall antibiotic usage, the importance of optimal nutrition and management has further increased.
The starter period is an important period in efficient broiler production: the period corresponds to about 26% of the broiler’s life and quality feed is a big factor in growth and development during this period leading to carryover effects throughout the full production period. Investing in quality broiler starter feed pays off at slaughter.
HAMLET PROTEIN
WHITE PAPER / Broiler Starter Feeds / 10
References References available upon request at info@hamletprotein.com and further information is available on www.hamletprotein.com • Adedokun S.A., C.M. Parsons, M.S. Lilburn, O. Adeola and T.J. Applegate, 2007. Endogenous amino acid flow in broiler chicks is affected by the age of birds and method of estimation. Poultry Science 86:2590-2597. • Amit-Romach, E., D Sklan and Z. Uni., 2004. Microflora ecology of the chicken intestine using 16S ribosomal DNA primers. Poultry Science, 83:1093-1098. • Aviagen, 2014. Ross 708 broiler: Performance objectives. • Bigot, K., S. Tesseraud, S., M. Taouis and M. Picard, 2001. Alimentation neonatale et development prococe du poulet de chair. INRA Prod. Anim., 14(4:219-230). • Castanon, J.I.R. 2007. Review – history of the use of antibiotic as growth promotes in European poultry feeds. Poultry Science, 86:2466-2471. • de Jong, I. and J van Harn, 2012. Footpad dermatitis in broilers. Management tools to reduce footpad dermatitis in broilers. Aviagen, 0912-AVN-34, 26 pp. • Francesch, M. and J. Brufau, 2004. Nutritional factors affecting excreta/litter moisture and quality. World´s Poultry Science Journal, vol. 60. • HAMLET PROTEIN Feeding Trial Report, FTB01GB, 2013. HAMLET PROTEIN. • HAMLET PROTEIN Feeding Trial Report, FTB02GB, 2011. HAMLET PROTEIN. • HAMLET PROTEIN Feeding Trial Report, FTB03GB, 2011. HAMLET PROTEIN. • HAMLET PROTEIN Feeding Trial Report, FTB04GB, 2012. HAMLET PROTEIN. • HAMLET PROTEIN Feeding Trial Report, FTB05GB, 2013. HAMLET PROTEIN. • HAMLET PROTEIN Feeding Trial Report, FTB06GB, 2014. HAMLET PROTEIN. • HAMLET PROTEIN Feeding Trial Report, FTB07GB, 2010. HAMLET PROTEIN. • HAMLET PROTEIN Feeding Trial Report, FTB09GB, 2012. HAMLET PROTEIN. • HAMLET PROTEIN Broiler Calculator. www.hamletprotein.com • Iji, P.A. and R.A. Swick, 2014. Use of novel protein sources and improved starter feed formulation for broiler chicks. Australia poultry CRC P.O. Box U242, University of New England, Armidale NSW 2351, Australia, 35pp. • Just, A., H. Jørgensen and J.A. Fernandez, 1981. The digestive capacity of the caecum colon and the value of nitrogen absorbed from the hind gut for protein synthesis in pigs. Br. J. Nutr. 46:209-219. • Knowles, T.G., S.C. Kestin, S.M. Haslam, S.N., Brown, L.E. Green, A. Butterworth, S.J. Pope, D. Pfeiffer, and C.J. Nicol, 2008. Leg disorder in broiler chickens: prevalence, risk factors and prevention. PLoS ONE 3(2): e1545. doi:10.1371/journal. pone.0001545. • Nasset, E.S., 1972. Amino acid homeostatis in the gut lumen and its nutritional significance. World Rev. Nutr. Diet. 14:134-153. • Noy, Y. and Z. Uni, 2010. Early nutritional strategies. World’s poultry science journal, 66:639-646. • Nyachoti, C. M., C.F.M de Lange, B.W. McBride and H. Schulze, 1997. Significance of endogenous gut nitrogen losses in the nutrition of growing pigs: A review. Can. J. Anim. Sci. 77:149-163. • Personal communication, 2014. Aviagen. Technical team, Aviagen, UK.
HAMLET PROTEIN
WHITE PAPER / Broiler Starter Feeds / 11
• Ravindran, V. and W.L. Bryden, 1999. Amino acid availability in poultry – In vitro and in vivo measurements. Aust. J. Agric Res. 50:899-908. • Rérat, A., 1978. Digestion and absorption of carbohydrates and nitrogenous matters in the hindgut of the omnivorous non-ruminant animal. J. Anim. Sci. 46:1808-1837. • Swidersky, 2004. Unpublished data. In: Leeson, S. and J.D. Summers, 2008. Commercial poultry nutrition, third edition. University books, P.O. Box 1326, Guelph, Ontario, Canada. • Uni, Z. and R.P. Ferket, 2004. Methods for early nutrition and their potential. World’s poultry science journal, 60:101-111. • Uni, Z., 2006. Early development of small intestinal function. In: Avian Gut Function in Health and Disease. G.C. Perry, ed. Carfax Publishing Co., Abingdon, UK. • Uni, Z., 2014. Feeding Newly Hatched Chicks. Presentation given at HAMLET PROTEIN´s Feed Your Brain-seminar held at EuroTier November 11, 2014.
Saturnvej 51 / DK-8700 Horsens / +45 7563 1020 info@hamletprotein.com / www.hamletprotein.com
MAHPAVIWPB01GB02
• van den Brand, H., R. Molenaar, I. van der Star and R. Meijerhof, 2010. Early feeding resistance against cold exposure in young broiler chickens. Poultry Science 89:716-720.