BONE CHARACTERISTICS OF BROILERS SUPPLEMENTED WITH VITAMIN D

Effect of 25-hydroxycholecalciferol supplementation with different dietary available phosphorus levels for broilers

1. Based on the hypothesis that 25-hydroxycholecalciferol (25-OH-D3) inclusion would optimise dietary mineral digestibility and ameliorate growth performance and bone mineralisation in available phosphorus (AvP) deficient-fed broilers, a trial was conducted to evaluate its effect on diets with different levels of AvP.2. Broilers aged 1-21 d were randomly assigned one of the eight treatments, consisting of four dietary levels of AvP (0.45%, 0.42%, 0.39%, and 0.36%) and with or without supplementation with 25-OH-D3 at 69 μg/kg of feed. All diets contained 100 µg/kg of vitamin D3 (cholecalciferol).3. The addition of 25-OH-D3 resulted in higher feed intake and body weight gain, and lower FCR (P < 0.05) compared to non-supplemented diets, whereas AvP levels had a quadratic effect only on feed intake. There were no interactions between treatment factors.4. Increasing AvP levels linearly reduced the ileal digestibility of Ca and P (P < 0.01) and supplementing 25-OH-D3 increased both Ca and P ileal digestibility (P < 0.05), without any interactions observed for ileal digestibility.5. There was an interaction, whereby 25-OH-D3 inclusion increased serum metabolites in broilers fed 0.36% to 0.42% AvP compared to the non-supplemented diets (P < 0.001), whereas, at 0.45% AvP, diets with or without 25-OH-D3 had similar results.6. The P content in bone linearly increased in line with AvP levels (P < 0.05) and supplementation of 25-OH-D3 increased ash bone content (P < 0.001).7. Broilers can benefit from 25-OH-D3 supplementation combined with cholecalciferol with regard to Ca and P utilisation and vitamin D status, allowing for a reduction of dietary AvP levels down to 0.36% without impairing growth performance or bone status.

Dietary vitamin D: growth, physiological and health consequences in broiler production

Vitamins are needed in trace amounts in dietary formulations for poultry; however, they are critical for the health, maintenance, and performance of important body organs. Broilers have a lot of leg issues because of their rapid development and lack of exercise. Because of commercial broilers have limited access to direct sunlight, vitamin D supplementation in the feed is critical to reducing the risk of bone deformation and maximizing development. Vitamin D deficiency causes skeletal abnormalities, which may lead also to financial problems. The latest scientific findings on the source, metabolism, mechanisms of action, and functions of vitamin D in broilers are the subject of this review paper.

Classic and Non-Classic Effects of the Duration of Supplementation of 25-Hydroxicholecalciferol in Broiler Chicken Diets

Simple Summary

Genetic programs of modern commercial-type broiler chickens are based on growth performance parameters associated with muscular growth, feed efficiency, and meat and breast yield. Therefore, highly bioavailable vitamin D₃ to sustain optimal muscle and bone development is necessary. In the present study the effect of different durations of supplementing of 25-hydroxycholecalciferol (25(OH)D₃) in broiler chickens was evaluated. Growth performance response, carcass and cuts yield, bone resistance, plasma concentration of 25(OH)D₃, and expression of the mTOR gene were evaluated. The use of 25(OH)D₃ in the diets for broilers during different feeding periods did not influence growth performance but increased the plasma concentration of 25(OH)D₃, and increased breast yield as the duration of the supplementation was extended. The supplementation of 25(OH)D₃ increased breast yield and protein deposition in the breast muscle which may have been a result of the epigenetic changes caused by this vitamin D (Vit D) metabolite.

Abstract

The present study aimed to determine the effect of different times of supplementation of 25-hydroxycholecalciferol (25(OH)D₃) in broiler chickens on the performance, carcass and cuts yield, bone resistance, plasma concentration of 25(OH)D₃, and expression of the mTOR gene. The treatments were a control diet (CD) supplemented with 3000 IU vitamin D₃/kg of feed from 1 to 46 d, or the CD + 2760 IU (69 mcg) of 25(OH)D₃/kg of feed from 1 to 21 d, from 1 to 35 d, or from 1 to 46 d. The period of supplementation of 25(OH)D₃ did not affect the growth performance of broilers, but the breast meat yield was linearly increased in response to increasing days of supplementation (p < 0.05). Birds supplemented with 25(OH)D₃ at the time of the analysis showed an increase (p < 0.05) in the plasma concentration of 25(OH)D₃ when compared to non-supplemented birds. The mTOR gene expression (p < 0.05), and breast protein deposition (p < 0.05) presented a quadratic response related to the supplementation period of 25(OH)D₃. The fat content of the breast linearly decreased (p < 0.05) as the period of supplementation was extended. The results also showed a positive linear correlation between mTOR expression and 25(OH)D₃ plasma levels (r = 0.593; p < 0.05).

Dietary supplementation with glycosaminoglycans reduces locomotor problems in broiler chickens

This study aimed to assess the influence of glycosaminoglycan (chondroitin and glucosamine sulfates) supplementation in the diet on the performance and incidence of locomotor problems in broiler chickens. A completely randomized design was carried out in a 3 × 3 factorial scheme (3 levels of chondroitin sulfate -0, 0.05, and 0.10%; and 3 levels of glucosamine sulfate -0, 0.15, and 0.30%). Each treatment was composed of 6 replications of 30 broilers each. The performance of broilers (average weight, weight gain, feed intake, feed conversion, and productive viability) was assessed at 7, 21, 35, and 42 d of age, whereas the gait score, valgus and varus deviations, femoral degeneration, and tibial dyschondroplasia were assessed at 21 and 42 d of age. Increasing levels of glucosamine sulfate inclusion linearly increased the weight gain from 1 to 35 and from 1 to 42 d of age of broilers (P = 0.047 and P = 0.039, respectively), frequency of broilers with no femoral degeneration in the right and left femurs, and the proliferating cartilage area of proximal epiphysis at 42 d of age (P = 0.014, P < 0.0001, and P = 0.028, respectively). The increasing inclusion of chondroitin and glucosamine sulfates led to an increase in the frequency of broilers on the gait score scale 0 (P = 0.007 and P = 0.0001, respectively) and frequency of broilers with no valgus and varus deviations (P = 0.014 and P = 0.0002, respectively) also at 42 d of age. Thus, chondroitin and glucosamine sulfates can be used in the diet of broiler chickens to reduce their locomotor problems.