Effect of different levels of sorghum inclusion and the addition of a serine protease on live performance of broilers from 1 to 35 days of age
Published:June 22, 2018
By:Albaraa Sarsour*1, Hernan Cordova-Noboa1, Edgar Oviedo-Rondón1, Pedro Ferzola1.
1 North Carolina State University, Raleigh, NC. Novus International, St. Charles, MO.
Sorghum can be utilized to replace corn in areas where corn is not readily available. Serine protease has been proposed to improve the digestibility of sorghum because it could degrade disulfide bonds of kafirin proteins. One experiment was conducted to evaluate the effects of sorghum inclusion level and the addition of a serine protease on chicken live performance from 1 to 35 d of age. Eight treatments from a 4x2 factorial arrangement with 4 inclusion levels of sorghum (0, 25, 50, and 100% replacement of corn) and presence or absence of protease (0 or 500 g/ton for 600,000 U/g), as main factors. A total of 1,280 Ross 708 d-old male chicks were placed in 64 pens with 20 chicks per pen raised on used litter. Group BW and feed intake (FI) were recorded at 0, 14, and 35 d. BW gain and FCR corrected by mortality BW weights were calculated at the end of each phase. Data were analyzed as a randomized complete block design with a 4x2 factorial arrangement with 8 replicates per treatment combination. There was an effect of sorghum level (P < 0.05) on BW at 35 d. The heaviest broilers were associated with the treatments that were fed 100% corn diets which were not different from 25 and 50% sorghum, but were heavier (P < 0.05) than the ones fed 100% sorghum diets. Similar effect (P < 0.05) was observed on BW gain from 14 to 35 d, and BW and FI from 1 to 35 d. There was a 2-way interaction effect (P < 0.05) observed on FI for sorghum level and enzyme. Broilers fed diets with 100% sorghum without the addition of a protease consumed less (P < 0.05) feed than the same diet with the addition of protease. Protease improved FCR in the starter from 1 to 14 d only in diets with 100% corn. This positive effect of protease (P < 0.05) on FCR was detected again from 14 to 35 and 1 to 35 d of age in diets with 100% corn. It was concluded that corn can be replaced with up to 50% sorghum and that the addition of a protease could improve FCR of broilers fed corn diets and FI in 100% sorghum diets.
Dr Albaraa, with the results presented, some points that I believe are part of the objectives of this study were not properly clarified; - there is no information on the effect of protease on diets containing sorghum. It should be considered that the use of the enzyme was in the sense of enable the inclusion of sorghum in diets to replace corn; - when reporting that up to 50% of sorghum can be included, it does not describe whether it is with the inclusion of the enzyme or not; - how the inclusion of the enzyme had a positive effect on the feed containing 100% maize, it was not specified whether using this treatment as a reference the use of up to 50% sorghum remains viable.; - another detail to be considered is that the conclusions of the study must be consistent with the title and objectives of wo
It is a good study but anticipated effects and interactions sorghum inclusion and tannin levels in diets were not considered. Serine protease act and improve digestibility of kafirin in sorghum-based diets. However, there is a positive correlation between kafirin and tannin content in grain sorghum. Therefore, it was quite important to consider not only levels of sorghum but also tannin levels. The effect serine protease will depend very much on the level of tannin content in the diet.
Excellent work. In Colombia, during the first semester of the year, the Nutrianalisis laboratory, analyzing the samples of sorghum sent by the clients, found that a high percentage of them (75%) correspond to the category high in tannins, content of condensed tannins of 3% (catechin equivalent). The application of enzymes, a solution to take better advantage of this resource that is often rejected.
Dr. John Kaijage, Your point of view on tannins content of sorghum is important to consider. In a study titled 'Cibenza DP 100 improves performance and energy utilization in chickens fed high tannin sorghum', it was concluded that the negative effects of using high tannins sorghum (Tannin value of 1.63%; catechin equivalent and a kafirin index of 5.20) in diets were decreased with the addition of serine protease enzyme.
Reference: Carvajal-Jiménez, J. G., Rincón, K., & Oviedo-Rondon, E. O. (2012). Poster #P340 Protease improves performance and energy utilization in broilers fed diets with high tannin sorghum. Poultry Science Vol. 91 (E-suppl. 1) 2012 Poultry Science Association Annual Meeting Abstracts (Vol. 82).
When we use Sorghum to replace Corn, normally there is more deposition of fat in broilers .The energy requirement of maintenance increases compared to corn.Need to study energy balance with or without out protease enzyme along with nitrogen balance study.
