9 research outputs found
The effects of an organic rearing system and dietary supplementation of an essential oil mixture on performance and meat yield of slow-growing broilers in two seasons
In this study, performance and carcass characteristics of slow-growing broiler chicks, reared in organic or conventional systems, and fed a diet with an essential oil mixture (EOM, 48 mg/kg diet), were evaluated in the autumn and spring seasons. The rearing system affected several performance indices, including body weight, feed intake and feed conversion ratio (FCR), but not mortality, within a high statistical significance at 42 and 81 days of age. However, this was observed only from 1 to 42 days in the spring trial. Dietary administration with EOM worsened the FCR at 42 and at 81 days of age in the autumn trial, but not in spring. Organically reared slow-growing chickens consumed less feed mixture per unit of body weight gain, but attained a higher final weight compared with those kept indoors. However, the effect was more pronounced in autumn, which displayed cooler temperatures and robust plant cover availability (i.e. lucerne and trifolium). The carcass yield and cut-up carcass yield were not affected by the rearing system, but EOM diet supplementation increased breast yield only in the spring. The results suggest that autumn conditions promote efficient organic chicken production in the subtropical climatic zone. The amount of herbage consumed represented up to 10% and 3% of the birds’ daily protein and ether extract requirements, respectively. Supplementing the diet with a mixture of plant essential oils did not support the hypothesis that phytogenic compounds may favourably affect gut function and poultry performance.Keywords: Broiler, carcass characteristics, essential oil, organic, performanc
Comparing the profitability of organic and conventional broiler production
Recently, organic broiler chicken production has received more attention worldwide. This study has carried out an economic analysis to compare the profitability of organic versus conventional growing systems per unit of broiler meat production. To achieve this goal, 400 slow-growing broiler chickens (Hubbard Red-JA) were reared in an organic production system, and the same number of fast-growing birds (Ross-308) in a conventional system. The profitability was deduced with an economic analysis that compared total costs and net income. Results showed that organic broiler meat can cost from 70% to 86% more with respect to variable and fixed costs when compared with conventional production. The main reasons for the higher cost of organic broiler meat were feed, labor, certification, and outdoor area maintenance. The proportion of fixed costs in total costs was 1.54% in the conventional system and 7.48% in the organic system. The net income per kg of chicken meat in the organic system was € 0.75, which is 180% higher than chicken meat grown in a conventional system (€ 0.27); however, the price of organic broiler meat sold in the present study was twice as high as that obtained for conventional broilers. In conclusion, organic broiler meat production was more profitable than conventional rearing
Performance and egg quality of aged laying hens fed diets supplemented with meat and bone meal or oyster shell meal
Meat and bone meal (MBM) and oyster shell meal (OSM) were supplemented to a basal diet (LMS), either alone or in combination, in order to assess the dietary influences of those complementary Ca sources on performance and egg quality of laying hens. Four hundred and thirty-two Brown-Nick hens, at the beginning of their second production period, were divided into four treatment groups with six replicates each. The final body weight of OSM-fed hens was highest, whereas others did not differ significantly. Hens receiving OSM produced more eggs and egg mass along with considerably greater feed intake than those on all the other treatments. Egg weight was not affected by the treatments except for the lower egg weight of the MBM+OSM treatment. Hens fed a diet supplemented with MBM laid at a rate of 1.14%, 3.66% points lower than those on the control and OSM treatments, respectively. Feed efficiency was not influenced by origin of calcium source. Egg shape index and eggshell weight did not differ among treatments. Eggshell thickness and eggshell breaking strength were higher in hens fed with MBM as compared to control and OSM fed birds. Similar to the tendency in shell quality, MBM inclusion in the diet tended to enhance albumen height and Haugh unit. Dietary treatment with OSM resulted in the highest serum Ca and P concentrations. These results indicate that partially replacing limestone with OSM in the laying hen diet provided significant improvements in egg production performance, whereas most of the egg quality traits were enhanced bydietary supplementation with MBM at 4%.Keywords: Animal by-product, egg shell traits, performance, serum mineral concentratio
Comparative evaluation of dietary supplementation with mannan oligosaccharide and oregano essential oil in forced molted and fully fed laying hens between 82 and 106 weeks of age
The aim of this study was to investigate the efficacy of feed-grade preparations of mannan oligosaccharides (MOS) and oregano essential oil (OEO) in forced molted or fully fed 82-week-old, laying hens. A 2 x 3 factorial experiment investigated the influence of molting vs. full feeding and dietary supplements [i.e., unsupplemented control, MOS (1 g/kg) diet, and OEO (24 mg/kg) diet] on production parameters, egg quality, serum stress indicators, blood constituents, tibial characteristics, liver antioxidant status, and cecal microflora composition. A total of 864 Single Comb White Leghorn hens were randomly assigned to 6 treatments, each with 6 replicates of 24 hens each, and studied for 25 wk. Hens were fed a molt diet containing of 50% alfalfa and 50% wheat bran (aa+wb) for 12 d, then returned to the laying ration. Results indicate that molt vs. full feed impacted more on most variables measured than supplementation or supplement type. Significant (P < 0.01) interactions between molting and diet were observed for the egg production, egg weight, egg mass, and feed conversion ratio (FCR). In fully fed hens, MOS supplementation improved (P < 0.01) the egg production, egg weight, and FCR, and an OEO addition significantly improved the egg production and FCR in forced molted hens. Molting improved egg quality despite the significant regression in ovary and oviduct weight (P < 0.01), though supplements showed no influence. The bone ash (P < 0.01) and mineral content (P < 0.05) of molted hens were significantly lower than those of fully fed counterparts; however, poor mineralization was not reflected in the bones' mechanical properties. No significant differences were observed among treatments for hematological characteristics. Both the MOS and particularly the OEO supplementation improved (P < 0.01) liver antioxidant status and mitigated the significant increase in cecal pathogenic bacteria after molt. Our results indicate that full feeding with an aa+wb diet is an effective non-feed-removal method for molted hens, the benefit of which can be improved with MOS and OEO supplementation
Effect of anticoccidial monensin with oregano essential oil on broilers experimentally challenged with mixed Eimeria spp
Essential oil of oregano (OEO) has proven to be a potential candidate for controlling chicken coccidiosis. The aim of the current study is to determine whether OEO and an approved anticoccidial, monensin sodium (MON), as in-feed supplements could create a synergism when combined at low dosages. Day-old broiler chickens were separated into six equal groups with six replicate pens of 36 birds. One of the groups was given a basal diet and served as the control (CNT). The remaining groups received the basal diet supplemented with 100 mg/kg MON, 50 mg/kg MON, 24 mg/kg OEO, 12 mg/kg OEO, or 50 mg/kg MON + 12 mg/kg OEO. All of the chickens were challenged with field-type mixed Eimeria species at 12 d of age. Following the infection (i.e., d 13 to 42), the greatest growth gains and lowest feed conversion ratio values were recorded for the group of birds fed 100 mg/kg MON (P < 0.05), whereas results for the CNT treatment were inferior. Dietary OEO supplementations could not support growth to a level comparable with the MON (100 mg/kg). The MON programs were more efficacious in reducing fecal oocyst numbers compared to CNT and OEO treatments (P < 0.05). Serum malondialdehyde and nitric oxide concentrations were decreased (P < 0.01), whereas superoxide dismutase (P < 0.05) and total antioxidant status (P < 0.01) were increased in response to dietary medication with MON and OEO. All MON and OEO treatments conferred intestinal health benefits to chickens by improving their morphological development and enzymatic activities. The results suggest that OEO supported the intestinal absorptive capacity and antioxidant defense system during Eimeria infection; however, it displayed little direct activity on the reproductive capacity of Eimeria. This might be the reason for inferior compensatory growth potential of OEO compared to that MON following the challenge. Combination MON with OEO was not considered to show promise for controlling chicken coccidiosis because of the lack of a synergistic or additive effect