SUMMARY
Improving the crumble/pellet percentage of feed has been argued to be difficult to obtain in the commercial industry due to the necessity of feed mills producing adequate feed volume within a time constraint. Broiler performance research often utilizes small numbers of birds per pen or experimental unit that may affect the estimation of variance components, potentially producing pen performance metrics that are less valuable for industry guidance. The objective of this study was to compare the performance of straight run Hubbard × Cobb broiler chickens receiving a standard crumble/pellet percentage (50%) vs a modestly improved crumble/pellet percentage (70%), in either large pen (46 birds) or small pen (23 birds) experimental units. All diets were batched, mixed, steam conditioned to approximately 82°C, extruded through a 4.8 × 38.1 mm pellet die, and crumbled at the West Virginia University pilot feed mill. Crumble/pellet percentage differences were obtained by grinding a portion of the complete feed then remixing. Treatments were replicated 10 times and fed for 1 to 38 d using a 2 × 2 factorial arrangement in a randomized complete block design to measure growth performance. Bird density and feeder space access was 0.06 m2/bird and 1.2 cm/bird, respectfully for both experimental units. Crumble/pellet percentage and pen size main effects did not interact for any growth performance metric. Broilers consuming improved crumble/pellet percentage had a tendency towards decreased feed intake (P = 0.07) and feed conversion ratio by 3 points (P = 0.1), but maintained a similar weight gain (P = 0.3). Large pens decreased live weight gain (P = 0.03). Improved crumble/pellet percentage increased pen coefficient of variation for ending weight (P = 0.05), likely due to competitive feeding behavior. These data suggest that modest improvements in crumble/pellet percentage may provide performance benefits, and feed quality variation effects on growth performance can be satisfactorily evaluated utilizing a small pen experimental unit.
Key words: crumble, pellet, broiler, pen size, feed conversion ratio.
Abstract published in The Journal of Applied Poultry. Research, 2016. 25:21–28 http://dx.doi.org/10.3382/japr/pfv054.
I consider it opportune to specify that the benefactor effect in the modulation of the intestinal microbiota, it is through its antimicrobial activity or through the same stimulation of eubiosis (balance of beneficial microflora). This will be repeated, apart from its other properties (eg control of avian coccidia, innunoimulation, etc); in an encouraging performance in the productive parameters: greater weight increase / day, lower feed intake, improved feed conversion and higher final weight at the time of the benefit. It is not in vain that phytobiotics are classified as modern growth promoters, as alternatives to antibiotics used as a premix, and that since 2006 the EU has banned their use.
Greetings from Peru.
I have evaluated a lot of essential oil products in my research lab with little effectiveness in a well balanced corn-soy diet. That said, a good quality pellet certainly aids in improved FCR and especially in hot weather conditions.
Interesting article (as mentioned by Steffen) and interesting discussion; reaching even the sanitation of feeds. Just a few words on the side topic. I fully agree with Luis and Gleen- the influence of butyrates on gut health and its positive influence on production results in broilers. Many organic acids, etheric oils and other eubiotics (used separate or as a mixture) have positive influence on Salmonella and/or other pathogenic microbes in feed and the gut. But we know also that none is enough effective to eliminate it. Similar problem we have with Clostridium or E.coli (eg. benzoic acid is very effective). As all above opinions, we agree that only combination of physical factors (pelleting/expanding), disinfection, organic acids, phytobiotics, etc., could solve/ minimize the problem.
Coming back to the main topic- there is evidence that poor quality pellets (too soft, much fines, small particle size <0,8mm) are worse than good mash feed (bigger particles 0,8-2,5 mm, not much fines).
The use of phytochemicals is an effective option in the context of avian pathology. But it is not the reason of this forum. So, focusing on the subject, it is propitious to mention that:
Because of its strong and pungent odor, butyric acid is commonly used in its Butyrate form (as a calcium or sodium salt). Recurrent studies have concluded that after supplementation with Butyrate, there has been an increase in the height of the villi and the depth of the crypts in pigs and birds (Galfi and Bokori, 1990, Leeson et al., 2005). The growth in the height of the villi favors the absorption surface of the small intestine and improves the perfomance in the utilization of nutrients, for which recent work has shown that when the Butyrate is orally ingested it can have beneficial effects on the productive parameters in monogastrics (Bergman, 1990; Smulikowska et al., 2006; Biagi et al., 2007; Hu and Guo, 2007; Mazzoni et al., 2008; Czerwinski et al., 2012).
Greetings from Peru.
The blend of herbal products has two main results: improvement in gut health by synergism effects but slightly lowered growth due to the reduction of feed consumption, which broiler producers do not desire.