Body Weight Of Broilers Research Articles

PSVI-2 Identification of correlations between aldehyde profiles of thermally oxidized soybean oils and growth performance of broilers

Abstract Feeding oxidized oils can cause adverse effects on the growth performance of broilers, which have largely attributed to the presence of lipid oxidation products (LOP) in oxidized oils. This study was conducted to identify the potential correlations between growth performance and aldehyde profiles of differently-prepared thermally oxidized soybean oils. Seventy-seven broilers were randomly assigned to one of seven diets containing 7.5% fresh soybean oil or thermally oxidized soybean oil (OSO), including 1) 22.5°C, 0h; 2) 45°C, 336h; 3) 67.5°C, 168h; 4) 90°C, 84h; 5) 135°C, 42h; 6) 180°C, 21h; 7) 225°C, 10.5h, respectively. Broilers were provided ad libitum access to experimental diets for 28 days. Broilers body weight (BW) and feed intake were recorded weekly to calculate the average daily gain (ADG), average daily feed intake (ADFI), and gain to feed (GF) ratio. The aldehydes in these oils were determined by the liquid chromatography-mass spectrometry (LC-MS) analysis. The correlations between individual aldehydes and ADG, ADFI, or GF were examined by partial least squares (PLS) analysis. Feeding 135°C, 42h oxidized oil significantly decreased the ADG, ADFI, and GF value compared with other groups (p < 0.001). Among 17 aldehydes identified in thermally oxidized soybean oils, C9-C11 unsaturated alkenals, including 2-decenal, 2-undecenal, 2,4-nonadienal, 4-hydroxy-2-nonenal, 2,4-decadienal, and 2,4-undecadienal, had better inverse correlations with growth performance than C5-C8 saturated alkanals in broilers, suggesting different toxic effects from these aldehydes.

Effect of Trichoderma reesei Degraded Date Pits Supplementation on Growth Performance, Immunoglobulin Levels, and Intestinal Barrier Functions of Broiler Chickens.

Date palm (Phoenix dactylifera L.) is a dominant fruit crop in most Arabian countries. Date pits, as a major byproduct which remained after consumption of date flesh, proved to be a valuable source of energy. The impact of degraded date pits (DDP) on growth performance, intestinal bacterial population, and expression profiles of intestinal genes in broilers was determined. Recent patents have been established on DDP from the European patent office (EP2586318B1), Hong Kong patent registry office (HK1184642) and by the United States patent and trademark office (US8968729B2 and US10265368B2). Solid-state degradation system (SSD) was used for the preparation of DDP using Trichoderma reesei. One-day-old Brazilian broiler chicks "Cobb 500" were randomly divided into six treatments with six replicates, which consisted of a normal diet containing only corn-soy (control), diet containing corn-soy + (20%, 50g/100Kg oxytetracycline), diet containing corn-soy + 10% (DDP), diet containing corn-soy + 0.2% mannan oligosaccharides (MOS), diet containing corn-soy + 0.1% mannose, and diet containing corn-soy + 0.2% mannose. There were no significant differences in body weight, feed intake, and feed conversion ratio (FCR) in broilers among the treatments. The bacterial count was significantly decreased in 10% DDP diet-fed broilers, 0.2% MOS and antibiotic diet-fed broilers. Immunoglobulin levels in serum and intestinal contents and expression pattern of genes in jejunum were upregulated in 10% DDP and 0.2% MOS diet-fed broilers. DDP can be used as an energy source for replacing part of corn, mannan oligosaccharide and also recommended as a potential alternative to antimicrobials in broilers diet.

Validation of genomic predictions for body weight in broilers using crossbred information and considering breed-of-origin of alleles

BackgroundPig and poultry breeding programs aim at improving crossbred (CB) performance. Selection response may be suboptimal if only purebred (PB) performance is used to compute genomic estimated breeding values (GEBV) because the genetic correlation between PB and CB performance (r_{pc}) is often lower than 1. Thus, it may be beneficial to use information on both PB and CB performance. In addition, the accuracy of GEBV of PB animals for CB performance may improve when the breed-of-origin of alleles (BOA) is considered in the genomic relationship matrix (GRM). Thus, our aim was to compare scenarios where GEBV are computed and validated by using (1) either CB offspring averages or individual CB records for validation, (2) either a PB or CB reference population, and (3) a GRM that either accounts for or ignores BOA in the CB individuals. For this purpose, we used data on body weight measured at around 7 (BW7) or 35 (BW35) days in PB and CB broiler chickens and evaluated the accuracy of GEBV based on the correlation GEBV with phenotypes in the validation population (validation correlation).ResultsWith validation on CB offspring averages, the validation correlation of GEBV of PB animals for CB performance was lower with a CB reference population than with a PB reference population for BW35 (r_{pc} = 0.96), and about equal for BW7 (r_{pc} = 0.80) when BOA was ignored. However, with validation on individual CB records, the validation correlation was higher with a CB reference population for both traits. The use of a GRM that took BOA into account increased the validation correlation for BW7 but reduced it for BW35.ConclusionsWe argue that the benefit of using a CB reference population for genomic prediction of PB animals for CB performance should be assessed either by validation on CB offspring averages, or by validation on individual CB records while using a GRM that accounts for BOA in the CB individuals. With this recommendation in mind, our results show that the accuracy of GEBV of PB animals for CB performance was equal to or higher with a CB reference population than with a PB reference population for a trait with an r_{pc} of 0.8, but lower for a trait with an r_{pc} of 0.96. In addition, taking BOA into account was beneficial for a trait with an r_{pc} of 0.8 but not for a trait with an r_{pc} of 0.96.

Profil Darah Merah dan Bobot Badan Ayam Broiler dipelihara pada Ketinggian Tempat yang Berbeda

The aims of this research was determine the difference in the profile of red blood and body weight of broilers kept in the highlands and lowlands. The material of this study used 40 starter and finisher period chickens aged 21 and 35 days. The parameters observed were the profile of red blood and body weight. Data were analyzed using a t-test to test an average of 2 populations. The results showed that differences in place height were not significantly different (P> 0.05) in the number of erythrocytes and hemoglobin but were significantly different (p <0.05) in hematocrit and body weight. The conclusion of this study the profile of red blood broilers kept at different altitudes is still normal under the erythrocyte and hemoglobin level but the increase in temperature in the lowlands increases hematocrit values and decreases production seen from the body weight of broilers falling below normal.

Discovery and characterization of functional modules associated with body weight in broilers

Aim of the present study was to investigate whether body weight (BW) in broilers is associated with functional modular genes. To this end, first a GWAS for BW was conducted using 6,598 broilers and the high density SNP array. The next step was to search for positional candidate genes and QTLs within strong LD genomic regions around the significant SNPs. Using all positional candidate genes, a network was then constructed and community structure analysis was performed. Finally, functional enrichment analysis was applied to infer the functional relevance of modular genes. A total number of 645 positional candidate genes were identified in strong LD genomic regions around 11 genome-wide significant markers. 428 of the positional candidate genes were located within growth related QTLs. Community structure analysis detected 5 modules while functional enrichment analysis showed that 52 modular genes participated in developmental processes such as skeletal system development. An additional number of 14 modular genes (GABRG1, NGF, APOBEC2, STAT5B, STAT3, SMAD4, MED1, CACNB1, SLAIN2, LEMD2, ZC3H18, TMEM132D, FRYL and SGCB) were also identified as related to body weight. Taken together, current results suggested a total number of 66 genes as most plausible functional candidates for the trait examined.

Proizvodni pokazatelji brojlera hranjenih dodatkom propolisa i pčelinjega peluda

The aim of this study was to determine the effect of diet supplementation with propolis and/or bee pollen on the performance indicators of broilers. This experimental study was conducted on 200 Ross 308 broilers equally distributed by sex and divided into five groups. Throughout the whole study the control group of chickens was fed feed mixture. Feed mixture fed to the experimental groups of chickens contained additives (propolis and/or bee pollen, each supplement separately or in combination in a certain proportion). The average values of broilers body weight were significantly higher on 7th (p=0.001), 14th, 21st, 28th, 35th (p<0.001) and 42nd (p=0.002) day of feeding in the experimental groups of broilers compared to the control group. The average values of broilers weight gain were significantly higher on 1st (p<0.001), 2nd (p=0.002), 3rd (p<0.001), 4th (p=0.029) and 5th (p=0.009) week of feeding in the experimental groups of broilers compared to the control group. This study has undoubtedly shown that propolis and bee pollen have significant positive effect on performance indicators of broilers.

Thermal manipulation of the broilers embryos: expression of muscle markers genes and weights of body and internal organs during embryonic and post-hatch days

BackgroundIn broilers chickens, the molecular bases for promoting muscle development and growth requires further investigation. Therefore, the current study aimed to investigate the effects of daily thermal manipulation (TM) during embryonic days (ED) 12 to 18 on body, carcass and internal organ weights as well as on the expression of muscle growth markers genes during late embryogenesis and post-hatch days. 1500 fertile Cobb eggs were divided into five groups. The first group was a control group and incubated at 37.8°C. The other four groups were thermally manipulated (TM) and exposed to 38.5°C (TM1), 39°C (TM2), 39.5°C (TM3) and 40°C (TM4) daily for 18 h, respectively, with a relative humidity of 56%. Body weights (BW) from ED 12 to 18 and on post-hatch days 1, 2, 3, 4, 5, 6, 7, 14, 21, 28 and 35 were recorded. mRNA expression levels of muscle growth factor genes (IGF-1 and GH) and muscle marker genes (Myogenic Differentiation Antigen; MyoD), Myogenin, Pax7, and PCNA) during ED 12 to 18 and on post-hatch days 1, 3, 5, 7, 14 were analyzed. On post-hatch day 35, the carcass and internal organ weights have been also evaluated.ResultsTM during certain days of embryogenesis (ED 12 to 18) did not affect the BW of broilers during their embryonic lives. However, TM, particularly TM1 and TM2, significantly increased BW, carcass and internal weights of hatched chicks near to the marketing age (post-hatch days 28 and 35). Most of TM protocols induced up-regulation of muscle growth factor genes (IGF-1 and GH) and muscle marker genes (MyoD, Myogenin, Pax7, and PCNA) during embryonic life (ED 12 to 18) and on post-hatch days.ConclusionAmong the various TM conditions, it seems that,TM1 and TM2 induced a significant increase in BW, carcass and internal weights of hatched chicks near to the marketing age. This increase in BW induced presumably via up-regulation of muscle growth factor genes and muscle growth markers genes during embryonic life (ED 12 to 18) and on post-hatch days. Both protocols (TM1 and TM2) can be used in real-world applications of poultry industry for maximum benefit.

Evaluation of Calendula officinalis L. (marigold) flower as a natural growth promoter in comparison with an antibiotic growth promoter on growth performance, carcass traits and humoral immune responses of broilers.

The objective of this experiment was to investigate the effects of dried powder of Calendula officinalis L. (marigold) flower as an antibiotic growth promoter substitute on growth performance, organ weights, and immunological parameters in broilers. A total of 240 mixed sex broilers (Ross 308) at 1 d of age were individually weighed and randomly assigned to 4 treatments with 4 replicates of 15 birds for 6 wk. The dietary treatments were: 1) a basal diet (control); 2) control plus 4.5 mg flavophospholipol/kg of diet; 3) control plus 5 g marigold/kg of diet; 4) control plus 10 g marigold/kg of diet. Antibody responses against Newcastle (NDV), influenza (AI) viruses, and sheep red blood cells (SRBC) were measured. Supplementing 4.5 mg flavophospholipol/kg of diet enhanced body weight (BW) of broilers at 14 and 28 d of age (P < 0.05), but final BW at 42 d was not markedly affected. At 14 and 28 d of age, broilers fed diets supplemented with 10 g marigold/kg of diet had significantly lower BW compared with broilers fed the basal diet supplemented with antibiotic or 5 g marigold/kg of diet. During the starter period, broilers fed diets supplemented with antibiotic had significantly (P < 0.05) better FCR compared with broilers supplemented with 10 g marigold/kg of diet, but did not differ from broilers fed the basal diet or basal diet supplemented with 5 g marigold/kg of diet. There were no significant differences in FCR between treatments, during grower, finisher phases as well as for the whole experiment. Carcass yield was significantly (P < 0.05) higher in broilers supplemented with 5 g marigold/kg of diet compared with broilers in other groups. The treatments failed to induce any marked effect on immune parameters. In conclusion, the results of this experiment showed that supplementation of 5 and 10 g dried powder of marigold/kg of diet has no affirmative influence on growth performance of broilers.

Summer Savory (Satureja hortensis L.) Extract as Natural Feed Additive in Broilers: Effects on Growth, Plasma Constituents, Immune Response, and Ileal Microflora.

Simple SummaryThe growth-promoting effect of many herbs and their extracts in poultry has been reported in literature. Therefore, the objective of this feeding trial was to determine the effect of different levels of summer savory (Satureja hortensis L.) extract in diet on broilers performance, immune response, hematology, and microbiota. Based on findings, dietary supplementation with summer savory extract, as natural feed additive, sustained growth traits and improved the feed efficiency and health status of broilers.This study investigated the effects of summer savory (Satureja hortensis L.) extract (SSE) on growth, plasma constituents, immune response, and gut microbiota of broiler chickens. A total of 300 day-old broiler chicks were randomly assigned to five dietary treatments containing five replicates of 12 birds each. The treatments consisted of a controldiet without feed additive and experimental diets supplemented with four levels of SSE (100, 200, 300, and 400 mg/kg, respectively). Results showed no significant effect of SSE supplementation on broiler body weight gain (p > 0.05), but feed conversion ratio was significantly (p < 0.05) improved when fed 400 mg/kg SSE compared to control. Most of the blood parameters and immune response criteria studied were improved (p < 0.05) by SSE supplementation. There was no dietary effect on Lactobacilli count (p > 0.05); conversely, Escherichia coli count was reduced and the Lactobacilli/E. coli ratio improved with SSE (p < 0.05). Based on our findings, it was concluded that supplementation of the diet with SSE up to 400 mg/kg sustained growth traits and improved the feed efficiency and health status of broilers. However, more research is needed on this subject in order to better understand the mode of action of the extract used.

Estimating the purebred-crossbred genetic correlation of body weight in broiler chickens with pedigree or genomic relationships

BackgroundIn pig and poultry breeding programs, the breeding goal is to improve crossbred (CB) performance, whereas selection in the purebred (PB) lines is often based on PB performance. Thus, response to selection may be suboptimal, because the genetic correlation between PB and CB performance (r_{pc}) is generally lower than 1. Accurate estimates of the r_{pc} are needed, so that breeders can decide if they should collect data from CB animals. r_{pc} can be estimated either from pedigree or genomic relationships, which may produce different results. With genomic relationships, the r_{pc} estimate could be improved when relationships between purebred and crossbred animals are based only on the alleles that originate from the PB line of interest. This work presents the first comparison of estimated r_{pc} and variance components of body weight in broilers, using pedigree-based or genotype-based models, where the breed-of-origin of alleles was either ignored or considered. We used genotypes and body weight measurements of PB and CB animals that have a common sire line.ResultsOur results showed that the r_{pc} estimates depended on the relationship matrix used. Estimates were 5 to 25% larger with genotype-based models than with pedigree-based models. Moreover, r_{pc} estimates were similar (max. 7% difference) regardless of whether the model considered breed-of-origin of alleles or not. Standard errors of r_{pc} estimates were smaller with genotype-based than with pedigree-based methods, and smaller with models that ignored breed-of-origin than with models that considered breed-of-origin.ConclusionsWe conclude that genotype-based models can be useful for estimating r_{pc}, even when the PB and CB animals that have phenotypes are closely related. Considering breed-of-origin of alleles did not yield different estimates of r_{pc}, probably because the parental breeds of the CB animals were distantly related.

Impact of Dietary Supplementation with Cress Seeds (Lepidium Sativum L.) on Growth Performance, Carcass Characteristics and Behavior of Broilers

The aim of this study was to investigate the effect of cress seeds supplementation on growth performance, carcass characteristics and behavior of broilers. A total of sixty-one- month day old cockerels were utilized for this study, obtained from a local commercial farm. They were randomly distributed to four groups (n=15, each) with three replicates within group. In the first group, birds were fed on basal diet without addition of cress seeds (CS) which was assigned as control. In second, third and fourth groups birds were fed on basal diet with supplementation of different concentrations of cress seeds (0.5 (T1), 1(T2) and 1.5 (T3) % respectively). The treatment was continued for 5 weeks period. The obtained results showed that supplementation with cress seeds at concentration of 1% has positive effect on broiler body weight, weight gain, feed consumption, production efficiency factor, broiler index and ingestive and sitting behavior. The relative weights of proventriculus, gizzard and heart were significantly affected by dietary inclusion of CS into broiler diets. Serum total protein and globulin were significantly (P

A growth model to predict body weight and body composition of broilers

Models predicting the nutrient partitioning and animal performance have been developed for decades. Nowadays, growth models are used in practical animal nutrition, and they have particular importance in precision livestock farming. The aim of the present study was to introduce a broiler model and to provide examples on model application. The model predicts protein and fat deposition as well as the body weight of an individual broiler chicken from digestible nutrient intake over time. Feed intake (FI) and the digestible nutrient content of the feed are inputs as well as some animal factors like: initial BW, feed intake at 1 and 2 kg of BW, precocity and mean protein deposition. The protein and energy metabolism is represented as in the classical nutrient partitioning models. The protein deposition (PD) is driven by digestible amino acid supply and is under “genetic control”, the so-called potential PD limits the actual PD if protein is oversupplied.&#x0D; The authors discuss how the model can be used to simulate the animal response upon different scenarios. Examples are given to show that the diet might be limiting if some animal trait is changed. Applicability of the model has shown through running the model by using different feed strategies (three- vs five-phase-feeding) and variations with animal factors. In conclusion, growth models are useful tools to support decision making for defining the most suitable feeds used in a broiler farm. The model presented in this paper shows a high sensibility and flexibility to test different scenarios. By challenging the model with different inputs, the animal response in terms of changes in body weight and feed conversion can be understood more by studying the shift in deposition of chemical constituents. The examples provided in the present paper shows the benefit of using mathematical models and their applicability in precision nutrition. It can be concluded that the growth model helps to apply “from desired feed to desired food” concept.

Effect of wood shaving litter density on the growth, leg disorders and manurial value in broiler

&#x0D; The study was conducted with an aim to investigate the effect of litter density on growth, leg health and litter quality of broiler chickens from d1-42 days. Day-old male broiler chicks (n=400; Cobb 500) were distributed randomly into four litter densities [T1, T2, T3 and T4] treatments, each treatment had 5 replicates with 20 birds per replicate cage in a completely randomized design. Wood shaving was used as litter materials to a thickness of 5 cm, 8 cm, 11 cm and 14 cm on the floor of the pen. Birds were reared on the litter floor open-sided housing condition with ad libitum feed and water throughout the trail period. Data on feed intake (FI), body weight (BW), feed conversion ratio (FCR) and mortality were measured weekly. Litter sample was collected on day 42 to assess the nitrogen content (N2 %), dry matter (DM%) and moisture level (%). Footpad dermatitis (FPD) and hock burn (HB) incidences were measured on day 42 to assess the leg quality of birds. Results demonstrated that litter thickness had no significant (P&gt;0.05) effect on FI, BW, FCR and mortality of broilers from d1-42 days. The N2, DM or moisture levels (%) of litter were also unaffected (P&gt;0.05) between treatment. Leg disorders such as HB and FPD were influenced (P&lt;0.01) by treatment. The incidences of HB and FPD were higher (P&lt;0.01) in T1 and T2 than other treatments. It can be inferred from our current study that, leg health may be deteriorated by using low density wood shaving without affecting growth and litter quality of broiler chickens.&#x0D; Bang. J. Anim. Sci. 2018. 47 (1): 21-27&#x0D; &#x0D;

한국 재래계의 HNF4α 유전자 내 SNP와 성장과의 연관성 분석

The hepatocyte nuclear factor 4 alpha (<italic>HNF4α</italic>) gene is related to lipid transport, including abdominal fat and growth, in chickens. Interestingly, the A543G SNP within the <italic>HNF4α</italic> gene has previously been reported to be associated with body weight in both broilers and Korean native chickens (KNCs). However, its exact position within the <italic>HNF4</italic> is not yet reported. This study aimed to identify the position of the A543G SNP and to identify additional SNPs that can be used as genetic markers in KNCs. A total of 128 KNCs were used for the sequencing and analysis of these genetic associations. As a result, A543G SNP was located in intron 4 of the <italic>HNF4α</italic> gene; it is reported as rs731246957 in the NCBI database. Fourteen SNPs were detected in the sequenced portion of the <italic>HNF4α</italic> gene; three of these, rs731246957, rs736159604 and new SNP, intron 6 (249), were significantly related with growth in the chickens. In this study, the TT genotype of rs731246957, previously reported as A543G SNP, the GG genotype of rs736159604 and GT of new SNP have are highly associated with body weight from birth to 40 weeks of age in KNCs (<italic>P</italic>&lt;0.01). These results suggest that rs736159604, rs731246957 and intron 6 (249) SNPs within the <italic>HNF4α</italic> gene could function as growth-related markers in the selective breeding of KNCs.

Survey on broiler pre-slaughter mortality in a commercial abattoir of central Italy.

The pre-slaughter mortality was investigated on broilers, in the Mediterranean climate condition, considering the most significant risk factors as the journey length, waiting time, season and the space allowance in cages. At first, the pre-slaughter mortality was studied considering the totality of birds and then by examining in detail three broiler categories: large, medium and small size. The average dead on arrival (DOA) recorded on the totality of birds throughout the year was 0.38% and the values obtained in winter, spring, summer and autumn were 0.52, 0.48, 0.31 and 0.22%, respectively. The mortality rate observed during the year was 0.52, 0.47 and 0.31% for large, medium and small broilers, respectively. In all three groups, the maximum values of mortality were obtained in winter, whereas the minimum ones were recorded in autumn, spring and summer for large, medium, and small size birds, respectively. The increase of journey length could cause a higher mortality rate whereas the increase of the waiting time in the facilities at controlled environmental conditions did not seem to be a risk factor, but rather a mean to reduce the number of dead animals (all P < 0.05). It is concluded that the resistance to the hostile weather conditions, long journeys and extended waiting times was strongly related with the body weight of broilers; therefore, the planning of the slaughtering activity should consider this aspect, in order to avoid animal suffering and the economic loss.

Effect of Sex and Day-Old Weight on Subsequent Body Weight and Body Mass Index in Commercial Broilers

Effect of Sex and Day-Old Weight on Subsequent Body Weight and Body Mass Index in Commercial Broilers

The effect of purslane hydroextract and zinc on performance, antioxidant capacity and immunity of broiler chickens during summer conditions

Abstract. Due to negative effects of high ambient temperature, the present study was conducted to investigate the effects of Portulaca oleracea hydroextract (PHE) and zinc (Zn) on the growth performance and immunity of broiler chickens reared under high summer ambient temperature conditions. A total of 420 day-old male broiler chickens (Ross 308) were randomly allocated to seven dietary treatments each replicated four times with 15 birds per replicate. The basal diet as the control diet was supplemented with 100 mg kg−1 butylated hydroxytoluene (BHT), or 300 and 600 mg kg−1 of PHE, 100 mg kg−1 of zinc and 100 mg kg−1 of zinc plus 300 or 600 mg kg−1 of PHE (ZP300 and ZP600). The result of the present study showed that Zn, PHE and their combination did not alter daily feed intake and feed conversion ratio. Although there was a tendency toward an increase in broiler body weight at 24 and 44 days of age (P=0.059 and P=0.061), the body weight of birds fed the basal diet supplemented with Zn reduced at day 10. The birds fed diets supplemented with BHT or ZP600 showed lower aspartate aminotransferase (ASAT) and lactate dehydrogenase activity at 24 days of age (P&lt;0.05), but it remains lower in the ZP600 group only for ASAT activity level at day 44. The results of the present study suggest that dietary PHE and Zn supplementation partially improved body weight and serum antioxidant capacity, superoxide dismutase activity and antibody titer against sheep red blood cells and Newcastle diseases in the broiler chickens during summer conditions.

DEVELOPMENT OF A TRANSFER FUNCTION FOR WEIGHT PREDICTION OF LIVE BROILER CHICKEN USING MACHINE VISION

The objective of this study was to process digital images to investigate the possibility of broilers body weight estimation based on the dynamic model. For this experiment, 2440 images were recorded by a top-view camera from 30 birds. An ellipse fitting algorithm was applied to localize chickens within the pen, by using generalized Hough transform. Chickens’ head and tail were removed efficiently using the Chan-Vese method. After that, using image processing, six body measures were calculated. Next, they were used to design a Transform Function (TF) model with weight measurements as output. Second-order dynamic models were used to predict the weight of life broiler chicken, without delay, stable and with the highest R2 were predominantly selected according to the Young Identification Criterion (YIC) criterion chosen models. It was observed that predicted values rigorously follow the real values. Moreover, the relative body weight errors of chickens in the early days of grow-out was much more than last days. The accuracy of TF for body weight prediction from a comparison between measured (absolute) and predicted total life body weights were estimated for all studied broiler chicken (R2=0.98).

Effect of different level of rosemary leave powder in diet on blood metabolites, carcass characteristics and broiler performance

This experiment was conducted to investigate the effect of rosemary powder in diet on blood metabolite and performance of broiler chickens. 180 one day broiler chicks were distributed in a completely randomize design with 4 treatments and 3 replicates and 15 bird in each. Experimental treatments were included: Control (without additive), 0.05, 0.1 and 0.2 percent of rosemary in diet. In 42 day of age one bird from each replicate was selected and slaughtering for carcass traits. The results were sowed use of 0.05 percent of rosemary could be significantly increased feed intake of broiler in starter period (p&lt;0.05). Also use of 0.1 percent of rosemary caused to significantly increase broiler body weight gain in overall of rearing period than 0.2 percent group (p&lt;0.05). Use of 0.1 percent rosemary in diet had a significantly feed conversion ratio (FCR) than T4 (0.2% rosemary). Experimental treatments had no significant effect on carcass traits, except in liver percent weight, which had significantly higher in T2 group (p&lt;0.05). Also experimental treatments had no significant effect on glucose, cholesterol, triglyceride level of broiler chickens in 42 day of age. The results of this experiment showed use of rosemary powder could be improved broiler feed intake in starter period.

Effect of different vitamin D3 metabolites on intestinal calcium homeostasis-related gene expression in broiler chickens

ABSTRACT The purpose of this study was to investigate the effects of vitamin D3 metabolites 1α-hydroxycholecalciferol (1α(OH)D3), 25-hydroxycholecalciferol (25(OH)2D3), and 1,25-dihydroxycholecalciferol (1,25(OH)2D3) on growth performance, bone quality, and intestinal calcium homeostasis-related gene expression in broiler chickens. One-day-old broilers were fed a basal diet and basal diet containing different vitamin D3 metabolites. The body weight, feed intake, and feed conversion ratio in control and experimental broilers were measured to assess the growth performance, mineral levels, and bone breaking strength. The duodenum [...]