Authors
Department of Poultry Science, Faculty of Agriculture, Zagazig University, Zagazig, Egypt
Abstract
Keywords
INTRODUCTION
One of challenges which was and still facing the poultry industry in the developing countries is high prices of soybean meal and corn which mainly used in poultry diets. So, nutritionists should exert more efforts to find nutritious and affordable feedstuffs from untraditional sources. Increasing costs of poultry feeds have continued to be a major drawback in the developing countries, as the cost of feed is nearly about 65 to 70% (Nworgu et al. 1999) and 70 to 75% (Opara, 1999) of the total cost of production vs. about 50 to 60% in the developed countries as reported by Tackie and Flenscher (1995). One of the best strategies to reduce the costs of poultry feeds is using alternative, available and locally cheaper ingredients (Abd El-Hack, 2015). Several researchers have emphasized the dire need for utilizing alternative feed ingredients derived from human or industrial uses (Durunna et al. 1999; Fanimo et al. 2007; Nsa et al. 2007). In this respect, nutritionists used a lot of alternatives in formulating poultry diets such as distillers died grains with solubles (DDGS) (Abd El-Hack et al. 2015a; Abd El-Hack et al. 2015c; Abd El-Hack and Mahgoub, 2015), raw Faba bean (Abd El-Hack et al. 2015b), sun flower meal (Alagawany et al. 2015) and broken rice (Ashour et al. 2015). By-products of rice are extensively abundant wastes from rice industry and the amount of their production depends mainly on type of rice and the milling rate (Esa et al. 2013). Recent studies showed the use of rice by-products as functional foods as a result of their content of phenolic compounds, vitamins, minerals and fiber which have the ability in lowering cholesterol as well as anti-atherogenic activity (Wilson et al. 2002). The reproductive part is known as rice germs, which germinate and grow into plants (OECD, 2004). The content of vitamin E in rice germ is about 5 times higher than that in rice bran. α-Tocopherol is the major component of vitamin E in rice germ; it is the best active form of vitamin E. Furthermore, rice germ involves a good amount of vitamins (B1, B2 and B6), fiber and neurotransmitter γ–aminobutyric acid (GABA), which is reported to have several beneficial health effects. It could help in lowering the blood pressure, enhancing cognition and lowering blood glucose levels. The level of γ–aminobutyric in rice bran is 5 times higher than the level in rice germ (Shanggong et al. 2007). Corn is the main cereal grain used in poultry feeds and production. The logistic costs caused an increase in corn price, particularly during off-season periods as reported by Moura et al. (2010). So, agro-industrial by-products such as broken rice could be a good alternative to corn due to its low price and high availability, as well as similar metabolizable energy and crude protein contents to that of corn gain (Daghir, 2008). Broken rice is consisting of broken grains derived from the process of sieving after rice hulls are removed. According to Central Laboratory for Food and Feed in Cairo, chemical composition of broken rice is: crude protein 8%, crude fiber 10.1%, ash 2% and metabolizable energy 3090 kcalkg diet (Ashour et al. 2015). Sugar beet pulp (SBP) is also one of alternatives that could be used in poultry diets. It is the solid residue which remains after sugar extraction from sugar beet roots that represents 6% of roots weight (Kjaergaard, 1984). Dried SBP is a rich by-product in carbohydrates, so it was used as a partial source of energy in the rations of growing calves, dairy cattle, lambs (Hemingway et al. 1986; Ayaşan et al. 2012) and rabbit (Volek et al. 2002). The majority of previous studies concluded that the nutritive value of SBP is comparable to corn or barley. The crude protein level in SBP is considered low. Abedo (2006) found that SBP content of crude protein averaged from 6.6 to 13.3% with an average value of 9.9%. Sugar beet pulp also includes high content of crude fiber which represents about 19.7% in average (Abedo, 2006). It is worthy to note that the fibrous carbohydrates of SBP are easily digested as a result of low content of its lignin and the amorphous structure of its cellulose. On the other hand, SBP is deficient in phosphorus, fat, certain β-carotene and vitamins which have been confirmed as the reason for even lower bioavailability of SBP nutrients. There are investigations on using either BR or SBP in laying Japanese quails diets (Swain et al. 2006; Oliveira et al. 2007), but little literature are available on the use of these feedstuffs for growing quails (Ashour et al. 2015). Therefore, this study aimed to evaluate the effects of the inclusion of BR and SBP together in the same diet as a substitute for corn in growing Japanese quails diets on growth performance, carcass yield and economics of production.
MATERIALS AND METHODS
Experimental design and husbandry
The present study was carried out at Poultry Research Farm, Poultry Department, Faculty of Agriculture, ZagazigUniversity, Zagazig, Egypt. All procedures of the experiment were carried out according to the Local Experimental Animal Care Committee and approved by the ethics of the institutional committee of Poultry Department, Faculty of Agriculture, ZagazigUniversity, Zagazig, Egypt. A total number of 324 unsexed one week old Japanese quails with average initial body weight of (24.14±0.54) were randomly assigned in a complete randomized design into 6 treatment groups, (54 chicks in each group). Each group of birds was subdivided into three replicates, each of 18 chicks. Each replicate was housed in a cage (90×40×40 cm3). Six experimental diets were formulated according to NRC (1994) to have a basal diet and five diets with graded levels of BR and SBP mixture (1:1) (3, 6, 9, 12 and 15%) as a substitution for yellow corn (Table 1). Chicks were grown in brooders with raised wire floors and were reared under the same managerial and hygienic conditions. The lighting pattern was 23 hours light: 1 hour dark. Feed and water were ad libitum throughout the whole experimental period (1-5 weeks of age). All chicks received feeds from placement until 35 days of age in mash form, according to its treatment.
Collection of the data
Growth performance
Chicks were weekly weighed individually at intervals. Mortality was daily recorded. Average daily feed intake (ADFI), body weight gain (BWG) and feed to gain ratio (FCR) were calculated from these data by period and cumulatively. Feed wastage was daily recorded and the data were used to estimate the feed consumption. Protein efficiency ratio (PER) was calculated from body weight gain divided by protein intake (Kamran et al. 2008).
Carcass characteristics
At the termination of the experiment, 30 birds (five each group) were sampled randomly for carcass evaluations at 5 weeks of age, weighed and manually slaughtered. The carcasses were weighed and the weights of the liver, gizzard and heart were recorded and expressed as g/kg of slaughter weight (SW). Carcass and dressed weights studied (dressed weight=carcass weight plus giblets weight) / live body weight.
Economic efficiency
Economic efficiency of the product (growth rate) was calculated from the input and output analysis based upon the differences in growth rate and feeding cost (Heady and Jensen, 1954).
Statistical analysis
Data was subjected to ANOVA procedure using a completely randomized design using the GLM procedures of SAS (SAS, 2001). The differences among means were determined using the post-hocTukey’s test. Statements of statistical significance are based on (P<0.05) unless otherwise stated.
RESULTS AND DISCUSSION
Growth performance
Results in Table (2) show live body weight and body weight gain of growing Japanese quails fed the different levels of BR and SBP replaced maize from 1 to 5 weeks of age. The results indicated that LBW and BWG were significantly (PMedugu et al. (2010) and Ashour et al. (2015) who found that the use of rice is a potential energy source and feeding trials using broken rice in poultry diets have produced good results. Furthermore, Swain and Barbuddhe (2008) pointed out that broken rice (rice kani) can replace maize in diets of Japanese quail chicks up to a level of 20% in the diet without any adverse impact on their performance with appreciable reduction in the cost of feed. Sethi et al. (2006) demonstrated that broken rice could replace up to 50% of dietary maize corn with no bad effects on quails growth performance. Nanto et al. (2012) observed that the final weight of broilers was higher when dehulled paddy rice was totally replaced corn in the diets. Also, Gonzalez-Alvarado et al. (2007) found that broilers fed a diet containing dehulled paddy rice as main energy source yielded better performance in compare with those fed corn and belonged this impact to the lower fiber and higher starch contents in rice. Similarly, Tester et al. (2006) reported that the good performance of birds fed diets containing dehulled rice can be attributed to lower amylase and non-starch polysaccharide contents, in addition to its smaller particle size. Contrarily, Edwin et al. (2002) reported no significant differences in body weight of broilers at eight weeks of age when fed diets in which broken rice replaced maize corn. For SBP effect, Pettersson and Razdan (1993) found that chickens fed diets contained 23 g of SBP/kg diet gave higher live body weights compared with the control group. On the other hand, Alagawany and Attia (2015) found no significant effect of SPB inclusion on live body weight and body weight change of laying Japanese quails. Feed intake (FI) was significantly (PVicente et al. (2008) who stated that broken rice is one of feedstuffs that relatively stimulate high glucose and insulin postprandial responses, so it could increase feed intake and weight gain. On the other hand, Edwin et al. (2002) found that feed intake and feed efficiency did not show any significant differences among treatments included different levels of broken rice. Also, Almirall et al. (1997) who stated that increasing SBP inclusion in the diet from 0 to 75 and 150 g kg–1 feed from 22 to 55 weeks of age had no effect on overall feed consumption of Hi‑sex laying hens. Gonzalez-Alvarado et al. (2010) found that the inclusion of 3% SBP in the diet declined feed intake from 25 to 42 days of age as compared to the control group. Furthermore, Filgueira et al. (2014) found that increasing levels of broken rice (0, 20, 40, 60, 80 and 100%) in replacement of corn did not affect feed intake, weight gain or feed conversion ratio (P>0.05). Brum et al. (2007) did not find any significant effects (P>0.05) on feed intake, weight gain, or feed conversion ratio by broken rice in broiler diets at the levels of 0, 20 and 40%. Ashour et al. (2015) found that feed intake was significantly (P
Table 1 Composition and calculated analysis of the experimental diets
1 Protein concentrate (48%) contains: crude protein: 48%; ME: 2533 kcal/kg deit; Calcium: 6.2%; Available phosphorus: 2.9%; Lysine: 2.3% and Methionine + cystine: 2.4%.
2 Calculated analysis according to NRC (1994).
3 According to AOAC (2003).
4 Caculated according to the price of feed ingredients when the experiment was started.
Table 2 Effects of treatment on live body weight and body weight gain of growing Japanese quail
The means within the same row with at least one common letter, do not have significant difference (P>0.01).
SEM: standard error of the means.
Table 3 Effects of treatment on daily feed consumption and feed conversion ratio of growing Japanese quails
The means within the same row with at least one common letter, do not have significant difference (P>0.01).
SEM: standard error of the means.
Authors added that the best FI was obtained in quails fed broken rice at level of 50% replaced corn maize diet, whereas quails fed broken rice at level of 30% replaced by corn maize diet had the best FCR compared to other treatments. Data in Table 4 illustrate the effect of treatments on PER for growing Japanese quails. The inclusion of BR and SBP significantly (P<0.01) impacted PER only at the first period (1-3 weeks of age).
Table 4 Effects of treatment on protein efficiency of growing Japanese quails
The means within the same row with at least one common letter, do not have significant difference (P>0.01).
SEM: standard error of the means.
The level of 12 % recorded the highest value (1.92) of PER followed by the level of 15% (1.91) compared by the control group and the other treatments. The improvement in FCR, BWG and protein efficiency ratio found in groups fed of 9, 12 and 15% of BR and SBP replaced maize diet in the entire period 1-5 weeks of age could be due to the existence of phenolic base compounds in rice by products and SBP, in addition to having good amounts of minerals, vitamins and fiber that can help to lower cholesterol and enact anti-atheogenic activity (Wilson et al. 2002; Alagawany and Attia, 2015; Ashour et al. 2015). Moreover, Shanggong et al. (2007) theorized that rice germ has a substantial concentration of vitamins such as B1, B2 and B6, fiber and neurotransmitter γ–aminobutyric acid (GABA), which is suggested to have several beneficial health effects which reflect finally in improving FCR and BWG. In addition, Swain and Barbuddhe (2008) reported that broken rice is free of aflatoxins that pose threat to the survivability of livestock's and poultry. Vicente et al. (2008) demonstrated that feedstuffs that stimulate relatively high insulin and glucose postprandial responses, such as BR and SBP, could improve feed intake and weight gain by animals fed diets containing increasing levels of these feedstuffs. These results are in agreement with those reported by Swain and Barbuddhe (2008) who found that broken rice can replace maize up to a level of 20% in Japanese quails diets without any adverse effect on their performance. Furthermore, Medugu et al. (2010) and Nanto et al. (2012) postulated that using rice by-products as potential energy source in poultry diets have produced good results. On the other hand, Brum et al. (2007) did not find any significant impact (P>0.05) on FI, BWG or FCR when evaluating the replacement of corn by broken rice in broiler diets at the levels of 0%, 20% and 40%. Moreover, Cancherini et al. (2008) also observed no significant effect of 22.5% dietary inclusion of broken rice on broiler growth performance.
Carcass characteristics
Results in Table (5) showed the carcass characteristics involving dressing, carcass, giblets, heart, liver and gizzard yield percentages. The evaluation of carcass traits showed that the inclusion of BR and SBP in the diets did not significantly affect dressing and carcass yield percentages of meat-type quails compared to the control group. Heart, liver, gizzard and giblets yield percentages were significantly (PSethi et al. (2006) who reported that growth performance was not influenced by replacing 50% of dietary corn by broken rice. Since, carcass and gizzard pigmentation linearly depressed with increasing levels of broken rice in broiler diets because of the lower content of carotenoids of this feedstuff (Brum et al. 2007). Our obtained results are in accordance with those of Filgueira et al. (2014) and Ashour et al. (2015) who assured that the substitution of broken rice for maize corn in the diets did not significantly affect dressing percentage, breast and leg yields of meat-type quails. The results of carcass yield are in line with those found in broilers by Brum et al. (2007) and Cancherini et al. (2008) who found no effect of corn replacement by broken rice at levels of 0, 20 or 40% in the diet on broiler carcass or cuts yields. In a partially agreement with our results, Nanto et al. (2012) observed that increasing the substitution level of corn by broken rice and dehulled paddy rice reduced gizzard weight. Authors attributed this effect to the declined activation of this organ as a result of the higher content of starch and lower non-starch polysaccharide in broken rice as previously reported by Choct (2002). In this context, Alabi et al. (2014) suggested that increasing the size of gizzard could occur due to the need for more grinding activities resulting from increased fiber content of the diet. This may explain the reasonable result of the weight of the gizzard in the present study, although the weight did not increase linearly, the existence of SPB played a good role in maintain the shortage of fibers which resulted from BR inclusion.
Economics
The economic feasibility evaluation is presented in Table 6. Data showed that the feed cost per kilogram of live weight gain was gradually depressed as the inclusion level of BR and SBP increased.
Table 5 Effects of treatment on carcass yield of growing Japanese quails at 5 weeks of age
The means within the same row with at least one common letter, do not have significant difference (P>0.01).
SEM: standard error of the means.
Table 6 Effects of treatment on the economics of growing Japanese quails
* Net revenue= price/kg meat - price of feed to produce one kg meat.
LE: Egyptian pound.
Net revenue and economic efficiency were gradually increased as the inclusion level of BR and SBP increased in replacement of corn in quails diets. It is clear that the economic feasibility was higher when birds fed the highest level of BR and SBP (15%) in the diet being 1.64 compared with the control and other treatments. Our findings are in agreement with those reported by Rao et al. (2000) who reported that BR could be completely used instead of corn in the diets of broiler breeder to reduce the costs of production at prices prevailing in that situation. Swain et al. (2006) pointed out that the cost of feed was reduced when 30% of corn was replaced by broken rice.
CONCLUSION
Based on the present findings, BR and SBP can be considered a potential substitute of corn in growing Japanese quail together in the same diet up to 15%. Since it is a by-product of rice processing or sugar beet pulp which composition may vary, studies for determination of metabolizable energy and digestible amino acid contents may allow maximizing its inclusion in quail diets.
ACKNOWLEDGEMENT
The authors acknowledge the Department of Poultry, Faculty of Agriculture, Zagazig University, (Egypt) for their cooperation.