Using Processed Feeds For Laying Quails ( Coturnix coturnix japonica )

The aim of this experiment was to determine the productive performance and egg quality of Japanese quails fed different types of processed rations (mash, extruded, or pelleted). One hundred and fortyfour 18-w-old quails (Coturnix coturnix japonica) were housed in galvanized wire cages and fed a 21.50% CP and 2850 kcal ME/kg basal feed supplied in mash, extruded, or pelleted form. Experimental data were analyzed by ANOVA as a complete randomized design, with three treatments (ration forms) and six replicates of eight quails each. When necessary, means were compared by Tukey's test at 5% significance. Quails fed pelleted feed presented higher egg production, feed intake, and egg mass weight as compared to mashand extruded-diet-fed birds. Under the conditions of the present experiment, it was possible to conclude that the feed physical form did not affect egg quality, except for pelleted diets, which promoted good production performance and high egg mass. However, the use of feed pelleting should be economically analyzed considering the final cost of egg production.


INTRODUCTION
All-mash feed is the typical physical form of layer diets.However, pelleted, ground, or extruded processed feed may increase layer productivity by reducing feed loss, preventing selective feeding, increasing feed nutritional density, improving feeding program characteristics, and destroying pathogenic microorganisms from feedstuffs (Behnke, 1992).
The supply of ground/pelleted feeds as alternatives to mash physical form is currently used as a method to obtain higher feed intake by layers, and consequently, better body weight gain and feed conversion ratio (Botura, 1997).
Despite the growth of quail egg market, breeding and nutrition of Japanese quails (Coturnix coturnix japonica) have received little attention from researchers, and are mainly based on producer expertise.In addition, there are few scientific evidences on the benefits of the physical processing of laying quail feeds in literature.Ariki et al. (1996) studied the effect of processed feeds on the performance and quality of laying hen eggs, and verified that birds need to be adapted to the processed diet before the production period.Production parameters were not influenced by feed physical form, except for egg weight.
According to Furlan et al. (1998), time of digesta transit in the quail intestine is very fast, which impairs nutrient digestibility.In addition, this parameter is related to diet composition, feed intake level, and to diet physical form (Leandro et al., 2001).
In this context, the present trial aimed at determining the performance and egg quality of laying quails fed different types of processed feeds (mash, pelleted, or extruded).) )

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Feed intake and feed conversion ratio (kg feed/ dozen eggs and kg feed/kg eggs) data were obtained every 21 days.Egg production per replicate was daily recorded to calculate total egg production per experimental group during three 21-d cycles.
Internal and external egg qualities were evaluated during the last four days of each production period,.All intact eggs from each replicate were individually identified, and weighed on a precision scale (0.01g).A sample of three eggs per replicate was used to determine eggshell thickness and Haugh Units.
Eggshells were washed, dried at environmental temperature for 72h, and then individually weighed for determination of shell weight relative to egg weight.
Eggshell thickness was measured at three points equally distant from the central part of the eggshell using a manual micrometer (Mitutoyo ® ).
Egg Haugh unit was determined by measuring albumen height as the distance between external albumen border and yolk of broken eggs placed on a flat glass surface, using a manual micrometer.Albumen height was correlated to weight, as suggested by Brant et al. (1951), according to the following equation: Haugh Units = 100 log (H + 5.57 -1.7 W0.37) Where: H = albumen height (mm); W = egg weight (g).
The obtained data were submitted to analysis of variance (ANOVA), and means were compared by Tukey's test at 5% of significance with the aid of SAEG (1998) software.

RESULTS AND DISCUSSION
Quail performance and egg quality results are presented in Table 2. Processed feeds affected (p>0.05)egg production, egg mass, and daily feed intake.As compared to the groups fed mash and extruded feeds, quails fed the pelleted feed presented higher egg production and mass weight.This may be attributed to improved diet digestibility caused by the process of pelletization, which changes the tertiary structure of proteins, favoring their digestion, and increasing amino acid availability for egg production (Vargas et al., 2001).However, these results are not consistent with those reported by Ariki et al. (1996), who did not observe any differences in egg production or feed intake of layers fed processed diets.In addition, those authors verified detrimental effects of the Birds were submitted to artificial light immediately after sunset, receiving a total of 17h of light daily.Feed and water were provided ad libitum during the entire experimental period.

MATERIALS AND METHODS
The experiment was performed at the poultry house of Iguatemi Experimental Farm of Maringá State University.One hundred forty four 18-w-old quails were evaluated for 63 days, during three laying period of 21 days.Maximum and minimum average temperatures were 32 °C and 20 °C, respectively.
Birds were housed in 38x25x14cm battery cages equipped with a nipple drinker and a trough feeder.A complete randomized experimental design, with three treatments (3 feed physical forms: mash, pelleted, and extruded) and six replicates of 8 quails each, was applied.
Basal feed was formulated taking into account feedstuff composition, as suggested by Rostagno et al. (2000) (Table 1).After mixing, one third of the feed was pelleted, one third was extruded, whereas the last third remained in the mash form.Both processed feeds were then ground to achieve a particle size that is accepted by quails, i.e., 1mm geometric diameter.) )

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disadvantages, such as higher production costs and reduction of the stability of some vitamins and/or enzymes added to the feeds (Nilipour, 1993).However, some benefits on bird performance are attributed to the use of pelleting, such as improvement of the digestibility of some nutrients, lower feed waste (Ávila et al., 1995;Maiorka, 1998), prevention of particle selection (Cherry, 1982), lower feed microbiological contamination (Nilipour, 1993), feed efficiency improvement, and higher egg production (Almirall et al., 1997) as compared to mash diets.

CONCLUSION
Under the conditions of the present experiment, it was possible to conclude that the physical form of the feed did not affect egg quality; however, it promoted better quail performance and higher egg mass.Nevertheless, the decision to pellet feeds must be economically analyzed taking into account the final cost of egg production.extruded feeds on eggshell percentage and thickness, which was not detected in the present experiment.The higher daily feed intake of quails fed the pelleted diet may be attributed to an enhancement of feed palatability and digestibility (Nakage et al., 2002), as pelletization improves nutrient digestibility due to the mechanical action, and the temperature and humidity employed in the process.Flemming et al. (2002) also observed higher feed intake of broilers fed pelleted feed as compared to a mash-fed group, as well as Parsons et al. (2006) with growing chickens.
According to López & Baião (2004), pelleted feed determines increase in feed intake and prevents the selection of large particles.Amerah et al. (2007), testing diet particle size and processing, observed higher weight gain and feed intake, as well as better feed conversion in broilers fed pelleted diets as compared to those fed mash diets.The authors suggested that this increase in feed intake was due to an improvement in dietary starch digestibility.The temperature used for pelleting, if adequately controlled, promotes partial starch gelatinization, solidifies protein, and favors the action and the access of the endogenous enzymes, promoting higher diet digestibility.In addition, pelleted feeds require less physical efforts to ingest them, with consequent lower energy expenditure by birds.According to Nilipour (1993), pelleted feeds results in higher feed intake, because it does not allow particle selection by the birds, as pelleting promotes better aggregation of the diet components, avoiding nutrient imbalance and feedstuff segregation during feed transportation and handling.In addition, pelleting increases feed physical density anddecreases feed volume with better adjustment to bag space, dust, and feed intake time by the bird, consequently improving feed efficiency.
The pelleting process may present some economical

Table 1 -
Ingredient and calculated composition of the basal feed.

Table 2 -
Effects of feed processing on the performance, and internal and external egg quality of laying quails.