Age Of Broiler Chickens Research Articles

Relative biological efficacy of methionine hydroxy analogue-free acid compared to dl-methionine in the broiler chickens.

In the broiler's diets based on corn-soya bean meal, methionine (Met) and cystine (Cys), known as sulphur amino acids (SAAs), are the first limiting indispensable amino acids because of their limited presence, which are supplemented with different synthetic sources. Evaluation of the biological effectiveness of these sources can be important in their correct replacement, especially in the starter and growth diets. The current study was done to assess the relative biological efficacy (RBE) of liquid Met hydroxy analogue-free acid (MHA-FA) in comparison with dl-Met (dl-Met) based on broiler performance traits at different levels of digestible SAA in the 1-11 (starter) and 11-25 (grower) days of age periods. Two experiments were developed with treatments consisting of a basal diet without Met addition that met the nutrient and energy requirements of broilers with the exception of SAAs (Met+Cys) and five increasing Met doses for both sources (dl-Met and/or MHA-FA), resulting in digestible SAA concentrations from 0.62% to 1.02% of diet in the starter period (Trial 1) and 0.59% to 0.94% of diet in the grower period (Trial 2). The multi-linear regression model and slope ratio method were employed to calculate the RBE of MHA-FA compared with dl-Met for measured variables. In both experiments, the results obtained during the starter and grower periods with the different Met supplementations show significant growth responses to digestible SAAs levels. By increasing dietary dl-Met and/or MHA-FA levels, the growth performance traits and immune responses were improved (quadratic; p<0.05). The RBE of MHA-FA compared to dl-Met on an equimolar basis was estimated 66%-89% (59%-79% on a weight-to-weight basis). It is concluded that the RBE of MHA-FA in comparison with dl-Met depends on broiler chicken age and what attribute is being evaluated.

Short communication: In ovo injection of all-trans retinoic acid causes adipocyte hypertrophy in embryos but lost its effect in posthatch chickens.

The regulation of adipose deposition in broiler chickens is an important factor for production efficiency to poultry producers and health concerns to customers. Although vitamin A and its metabolite [all-trans retinoic acid (atRA)] have been used for studies on adipogenesis in mammals and avian, effects of embryonic atRA on adipose development in embryonic (E) and posthatch (D) ages in broiler chickens have not been studied yet. Different concentrations of atRA (0M-2μM) were injected in broiler eggs at E10, and adipose tissues were sampled at E16. Percentages of adipose tissues in chicken embryos were significantly increased in the group injected with 500nM of atRA compared to the 0M group (P<0.05). In addition, the adipocyte cross-sectional area (CSA) was significantly greater by in ovo injection of 500nM atRA compared to the injection of 0M (P<0.01). Moreover, in ovo atRA-injected embryos were hatched and BWs were measured at D0, D7, and D14. BWs were not different from those of the 0M group. Percentages of adipose tissues and CSA of the in ovo atRA-injected group (500nM) were not different from those of the 0M group at D14. Taken together, the current study clearly showed that in ovo injection of atRA promoted adipose deposition with hypertrophy during embryonic development, but its effects were not maintained in early posthatch age in broiler chickens, implying that embryonic atRA has an important role in the regulation of adipose development in chicken embryos.

Broiler Age Influences the Apparent Metabolizable Energy of Soybean Meal and Canola Meal.

The effects of broiler age on the apparent metabolizable energy (AME) and nitrogen-corrected AME (AMEn) of soybean meal (SBM) and canola meal (CM) were examined. A corn-SBM basal diet was developed, and two test diets were formulated by substituting (w/w) 300 g/kg of the basal diet with SBM or CM. Six groups of broiler chickens, aged 1-7, 8-14, 15-21, 22-28, 29-35 or 36-42 d post-hatch, were utilized. Each diet, in pellet form, was randomly allocated to six replicate cages in each age group. Except for the 1-7 d age group, the birds were fed a starter (d 1-21) and/or a finisher (d 22-35) diet prior to the introduction of the experimental diets. The number of birds per cage was 10 (d 1-7), 8 (d 8-14) and 6 (d 15-42). The AME and AMEn of SBM and CM were determined by total excreta collection. The data for each protein source were subjected to orthogonal polynomial contrasts using the General Linear Models procedure. Bird age decreased the retention of dry matter quadratically (p &lt; 0.001) for both SBM and CM. The retention of nitrogen decreased linearly (p &lt; 0.001) with the advancing age of broilers for SBM and CM. The AMEn of SBM and CM decreased quadratically (p &lt; 0.001) as the birds grew older. The highest AMEn was observed during week 1 for both SBM and CM, then declined until week 3, followed by increases thereafter. The current results showed that the age of broiler chickens influenced the AMEn of SBM and CM and supported the use of age-dependent AMEn of feed ingredients in diet formulations.

Effects of broiler chicken age and dietary protease on the standardised ileal digestibility of amino acids in seeds from two lupin species

Abstract The extent to which lupin seeds can replace soybean meal in diets for broiler chickens is limited, and one of the reasons for this may be a lack of careful consideration given to the age-related amino acid availability differences in the feed formulation process. This study aimed to determine and compare standardised ileal digestibility (SID) coefficients of amino acids (AA) in raw seeds of the Lupinus luteus (YL) and the Lupinus angustifolius (NLL) cultivars as sole sources of AA in the diet of broiler chickens aged 14 or 28 days. An additional purpose was to check the influence of exogenous mono-component protease added to lupin-based assay diets on AA SID in birds at both ages. Each assay diet was offered to six replicatecages. On both sampling days, the contents from the lower half of the ileum were collected for determination of the apparent digestibility values. The SID coefficients were calculated using the age-appropriate basal ileal endogenous AA losses determined from birds fed a N-free diet. Results indicated a substantial advantage of YL over the NLL in SID of Met, Cys, His, Leu, Gly, Asp, Glu, Pro, Tyr and the average of total AA for 14-d-old chickens. With the exception of Cys and Tyr, there was no significant difference between these Lupinus species in the SID of AA in 28-d-old birds. The significant age-related differences within species were found only for the seeds of NLL, where the higher SID for Met, His, Ala, Pro, and the averages of total and indispensable AA were noted in birds aged 28 d. The protease increased SID of most AA from L. luteus in older broilers, whereas for L. angustifolius its efficacy was more pronounced in younger birds, giving the SID values similar to those determined at 28 d on an enzyme-unsupplemented diet. In conclusion, the SID coefficients of indispensable AA determined at 14 or 28 days of age for yellow lupin should not be applied to the precise formulation of starter-type feeds containing seeds of NLL.

Age quadratically affects intestinal calcium and phosphorus transporter gene expression in broiler chickens.

This research aimed to evaluate the effects of age on growth, tibia development, and intestinal calcium (Ca) and phosphorus (P) transporter gene expressions in broiler chickens. A total of 224 male Arbor Acres broilers were fed with nutrient-adequate diets and reared in eight cages (28 broilers per cage). Eight broilers (one broiler per cage) were selected and killed at 5, 10, 15, 20, 25, 30, 35, and 40 days of age, respectively. Body weight continuously increased with age of broiler chickens from 5 to 40 days. The bone weight, ash weight, diameter, and length of the tibia also increased with broiler age. By contrast, the tibia ash, Ca, and P percentages quadratically changed with age (p<0.001), and the highest values of mineral contents were observed at 20, 25, and 25 days of age, respectively. The mRNA abundances of calcium-binding protein 28-kDa (CaBP-D28k), sodium-calcium exchanger 1 (NCX1), and plasma membrane ATPase 1b (PMCA1b) increased from 5 to 25 days and then decreased up to 40 days. Similar results were noted in the mRNA abundances of IIb sodium-phosphate cotransporter (NaPi-IIb), inorganic phosphate transporter 1 (PiT-1), inorganic phosphate transporter 2 (PiT-2), nuclear vitamin D receptor (nVDR), and membrane vitamin D receptor (mVDR). The mRNA abundances of Ca and P transporters and VDRs were the highest at 25 days of age. These data indicate that age quadratically affects intestinal Ca and P transporter gene expression and mineral absorption capacity in broiler chickens.

Research Note: Estimation of individual feed intake of broiler chickens in group-housing systems

In most experiments, broiler chickens are group-housed and share the same feeder in a given cage or pen. Correction of feed intake in a given pen is sometimes required in the event of mortality or identification of birds within a pen as outliers. For this reason, an accurate estimation of individual feed intake (IFI) is important. The objective of this study was to compare 3 different methods of estimating the IFI of broiler chickens in group-housing systems. The methods utilized in the current study consisted of an averaging method, a ratio method, and a partitioning method. The assumption of the averaging method is that birds in a cage consume an equal amount of feed, whereas feed intake of a given bird is proportional to its BW gain in the ratio method. The partitioning method bifurcates IFI into IFI for maintenance and growth. To validate these methods, 32 male broiler chickens (initial BW = 161 ± 19 g) at d 7 post hatching were individually housed in cages. Birds were fed a corn-soybean meal-based diet for 28 d, and body weight and feed disappearance were recorded on d 14, 21, 28, and 35. Excreta were collected over the last 3 d of each week. As age of broiler chickens increased, body weight gain, feed intake, and dietary metabolizable energy both linearly and quadratically increased, whereas gain-to-feed ratio both linearly and quadratically decreased (P < 0.05). The partitioning method estimated IFI more accurately compared with the averaging method and the ratio method (P < 0.05). The current result implies that the partitioning method would accurately estimate IFI of broiler chickens in group-housing systems.

ANALYSIS OF PRODUCTION PERFORMANCE AND FINANCIAL VIABILITY OF A BROILER CHICKEN FARMING BUSINESS IN A CLOSED HOUSE SYSTEM (Case Study At Ud. Pande In Pejeng Village, Tampaksiring Sub-District, Gianyar District)

&#x0D; &#x0D; &#x0D; This study aims to determine the performance of production, the feasibility of financial and Break Even Point of broiler chicken with the closed house system. The research starting from February 2020 until March 2020 in UD. Pande located in Pejeng Village, Tampaksiring District, Gianyar Regency. This study used primary and secondary data. Variables observed in this study is the performance of production broiler chickens include: body weight, we- ight gain, Feed Conversion Ratio (FCR), depletion and Performance Index (IP), as well as the feasibility of financial include: Net Present Value (NPV), Internal Rate of Return (IRR), Net Benefit per Cost (Net B / C), Pay Back Period (PBP) and Break Even Point (BEP). The data research analyzed with quantitative descriptive analysis. The results of the research study show that the average harvesting age of broiler chickens is 34 days, the average harvest weight 1,880 kg, the average body weight gain 1,836 kg, the average FCR 1.583, the average depletion 3,82%, the average performance index 328,81. Based on the results of financial analysis, this farm produces NPV 103,772,930, IRR 16,35%, Net B/C 1.40, Pay Back Period within 0.37 years, BEP within 9.97 years, BEP of production live chickens of 132,600 kg/year, BEP, of the price of live chickens Rp. 14.924/kg. Based on these results, it can be concluded that the broiler chickens reared with the closed house partnership system are good and feasible to run.&#x0D; &#x0D; &#x0D;

Theoretical basis of obtaining poultry products of «organic» status

The authors considered organic poultry production and presented a qualitative analysis of the diets used in raising broiler chickens. The authors also evaluated the possibility of switching from traditional diets to diets without chemical and microbial synthesis ingredients based on comparative data on the performance and economics of broiler chicken meat production. Organic requirements prohibit the use of microbial and chemical synthesis and genetically modified products in poultry feed. Obtaining large quantities of poultry products in a short period and at an affordable price involves using all kinds of additives that do not allow the products to qualify as organic. Surveys and opinion polls show that a new layer of consumers is today willing to buy organic poultry meat at a higher price. The aim of this work is to evaluate the possibility of producing organic meat from broiler chickens. The research was carried out at the Berdskaya poultry farm, and the test object was broiler chickens of the Iza cross. The age of broiler chickens ranged from one to 40 days old. The authors compared the effectiveness of traditional industrial diets and diets without microbial and chemical synthesis products. During the experiment, live poultry weight, average daily and gross gains, survival, feed costs and cost-effectiveness were considered. In commercial broiler chickens raised on diets without chemical and microbial synthesis ingredients during slaughter, the average live weight was 64.0% lower than that of broiler chickens in the experimental group. The average daily gain of these same broilers was also 52.9% lower. Feed costs per unit of production in industrial broiler chickens increased 1.7 times with the same survival rate of young animals (92.2%). Increasing the rearing period to 70 days resulted in a 1.4-fold increase in feed costs. The level of profitability decreased by 61.2 %, with a decrease in productivity. Increasing the price per kg of meat by 25 50 100 % would increase the profitability level by 22.4 4.7 -133.5 %, respectively, compared to the traditional method.

A chicken DNA methylation clock for the prediction of broiler health

The domestic chicken (Gallus gallus domesticus) is the globally most important source of commercially produced meat. While genetic approaches have played an important role in the development of chicken stocks, little is known about chicken epigenetics. We have systematically analyzed the chicken DNA methylation machinery and DNA methylation landscape. While overall DNA methylation distribution was similar to mammals, sperm DNA appeared hypomethylated, which correlates with the absence of the DNMT3L cofactor in the chicken genome. Additional analysis revealed the presence of low-methylated regions, which are conserved gene regulatory elements that show tissue-specific methylation patterns. We also used whole-genome bisulfite sequencing to generate 56 single-base resolution methylomes from various tissues and developmental time points to establish an LMR-based DNA methylation clock for broiler chicken age prediction. This clock was used to demonstrate epigenetic age acceleration in animals with experimentally induced inflammation. Our study provides detailed insights into the chicken methylome and suggests a novel application of the DNA methylation clock as a marker for livestock health.

Effect of probiotic supplementation on performance, morphology and gene expression associated with immune responses in early age of broiler chickens exposed to stress induced by corticosterone injection

Context Broiler chickens are exposed to various stressors, which can affect production performance. The use of dietary probiotics is one of the feasible methods to maintain performance, intestinal health, humeral immunity, and ameliorating physiological stress in the broiler. Aims In all, 288 1-day-old male broiler chicks were used to evaluate the effect of probiotic supplementation on performance, morphology, and gene expression associated with immune responses in the starter phase of broiler chickens exposed to stress. Methods In total, 288 1-day-old male broiler chicks (Ross 308) were assigned to evaluate the effects of Bacillus subtilis spore (BSS; Gallipro®200) supplementation at three levels (0, 0.8 × 105 colony-forming units (CFU) and 1.6 × 105 CFU/g feed) with corticosterone (CORT; 4 mg/kg BW at 7–9 days of age) or without CORT (oil) subcutaneous injection. The experiment was conducted in a completely randomised 2 × 3 factorial design. Key results CORT injection and probiotic supplementation led to an increase and decrease respectively, in food conversion ratio compared with the control group (P &lt; 0.05). CORT injections reduced the expression of TLR4, HSP70 and IgA in all parts of the intestine. However, the TLR4 gene expression increased in jejunum by CORT injections. BSS supplementation induced the expression of TLR4 in all sections of the intestine, both in stress and non-stress conditions. In stress-exposed chickens, IgA expression in the jejunum was affected by BSS supplementation. Interaction effects between CORT injections and BSS supplementation on the gene expression were significant in different parts of the intestine. Conclusions Chicks exposed to stress conditions induced by CORT injection showed that the ileum was more susceptible than were the other parts, especially for TLR4 and HSP70 gene expression. BSS-supplemented birds showed more capability to face the stress condition, probably due to intestinal health and immunity-modulated effect of BSS. Implication Formulating a ration with a probiotic can be more effective in stress conditions, through modulating immune-responsive genes in the intestine.

Additivity of apparent and standardised ileal digestibility of phosphorus in corn and canola meal mixed diets; basal endogenous loss of phosphorus responses to phytase and age in broiler chickens

ABSTRACT 1. The additivity of apparent ileal digestibility (AID) and standardised ileal digestibility (SID) of phosphorus (P) in mixed diets containing corn and canola meal (CCM) with or without phytase supplementation and the impact of age on the basal ileal endogenous loss (BEL) of P were investigated in broiler chickens. 2. Treatments were arranged as a 2 × 3 × 2 factorial with two ages (13 d or 21 d post hatching), three diets (corn, canola meal, or CCM), and two phytase levels (0 or 1,000 FYT/kg diet) in a randomised complete block design. There were eight or six birds per cage at 13 d and 21 d of age, respectively, and six replicate cages per treatment, with a total of 588 birds. A P-free diet (PFD) treatment was included at each age to determine the basal endogenous loss (BEL) of P. 3. Birds were fed a commercial starter diet from d 1 to d 10 or d 18 and then fed the experimental diets for 3 d until d 13 or d 21, respectively. Predicted digestibility values calculated from the individual feed ingredients were used to test additivity in the mixed diets. Chromium oxide was included in diets as an indigestible marker. 4. The ileal digesta, collected from birds at d 13 or d 21, was used to determine nutrient digestibility. 5. The AID and SID of P at d 13 was higher (P < 0.01) when compared with older birds at d 21, regardless of dietary phytase supplementation. Regardless of age or phytase supplementation, AID and SID of P were additive, as there were no differences between predicted and determined values in the mixed diets. The BEL of P (g/kg DM intake) in birds at d 13 was higher (P < 0.05) than birds at d 21 (0.197 vs. 0.159). 6. In conclusion, age had an impact on the BEL of P and the utilisation of minerals in the diets. The apparent and standardised ileal digestibility of P in the mixed diet containing corn and canola meal were additive, regardless of age or phytase supplementation.

Prevalence and characteristics of extended-spectrum β-lactamases-producing Escherichia coli from broiler chickens at different day-age

Commensal Escherichia coli from the poultries have been considered as reservoirs of extended-spectrum β-lactamases (ESBL)-encoding genes. Between May 2018 and March 2019, a total of 340 E. coli isolates were obtained from apparently healthy broiler chickens from 20 to 40 D old, distributed in 17 small-scale commercial farms. Finally, 45 isolates (8 from 20-day-old broiler chickens, 14 from 30-day-old ones, and 23 from 40-day-old ones) were identified as ESBL producers, which were further investigated to shed light on the virulence gene profiles, phylogenetic groups, and multilocus sequence types and to detect the ESBL plasmid-mediated quinolone resistance determinant (PMQR) genes as well as the mutations in the quinolone resistance-determining regions (QRDR) of gyrA and parC. Molecular analysis showed that phylogenic group A and B1 accounted for 66.7% of the ESBL producers. The overall occurrence of virulence genes ranged from 5.1% (cva) to 86.7% (papC). Twenty (44.4%) ESBL producers were considered as biofilm producers with moderate or heavy biofilm formation. The most predominant specific CTX-M subtype was blaCTX-M-14 (n = 19), followed by blaCTX-M-9 (n = 17), blaCTX-M-55 (n = 9), blaCTX-M-15 (n = 6), blaCTX-M-1 (n = 5), and blaCTX-M-65 (n = 4). Additionally, PMQR genes were identified in 86.7% of ESBL producers, qnrS (n = 21) was the most dominant PMQR gene, followed by the aac(6′)-Ib-cr (n = 15), qnrB (n = 12), and qnrA (n = 9), and all of them co-expressed with β-lactamase genes. All PMQR-positive isolates harbored simultaneously at least 1 mutation in the QRDR of gyrA and parC. Forty-five ESBL producers were assigned to 33 sequence types, and the most frequent sequence types (STs) was ST10 (n = 5) and followed by ST95 (n = 3). Additionally, ST302, ST88, ST410, ST187, and ST23 were represented by 2 ESBL producers, respectively, and the remaining ones exhibited diverse ST. Moreover, the prevalence of ESBL producers, the biofilm-forming ability, and the occurrence of the QRDR mutations among the E. coli isolates were characterized by gradually increased with advancing age of broiler chickens.

Effect of Environmental Enrichment on the Body Weight in Broiler Chickens

ABSTRACT The present study had the objective of analysing the impact of the use of environmental enrichment (music and light stimuli), broiler sex, and age in broiler chickens’ weight during growth. The observational study was carried out on a commercial farm. The environmental enrichment consisted of broilers’ stimulation by sound and light, and a house was kept without stimulus (control). The music stimuli consisted of different music styles and was played during the experiment to promote motivation for the birds. The light stimuli came from a coloured (red and green) LED strobe projector. Both stimuli were applied once a day for about 6 minutes, for five weeks. The broilers were weighed at the end of each week of growth. Throughout the growth period, broiler behaviours were analysed weekly through videos, and the leg disorders of the birds were put into score evaluations. The effects of the environmental enrichment type, gender, and age, and the probable interactions of these variables, on the weight of the broiler chickens were analysed by the comparative analysis of means, analysis of variance (ANOVA), and Tukey test of multiple comparisons. 7, 14, and 21 day old broiler chickens did not differ on body weight when compared with age, gender, and environmental enrichment (broiler house) (p>0.05). Males from 21 days of age had an increase in body weight when compared with females. Light enrichment presented the lowest body weight when compared with all studied houses, while the absence of enrichment presented the highest broiler weight.

Influence of supplementation of vitamin E on amelioration of ochratoxicosis in broiler chickens

In the present study, the effect of vitamin E supplementation in ochratoxin A (OTA) contaminated diet in amelioration of ochratoxicosis in broiler chickens was investigated. Day-old broiler chicks (n=240) were divided into six treatment groups (T1-control (basal diet); T2–T1 + 200 ppb OTA; T3–T1 + 100 mg vitamin E; T4–T1 + 200 mg vitamin E; T5–T2 + 100 mg vitamin E and T6–T2 + 200 mg vitamin E). Each diet was fed to 5 replicated groups of 8 birds each from 0 to 42 days of age. During overall growth period (0–6 week of age), the body weight gain (BWG) in ochratoxin contaminated diet (T2) fed group was lower than that of control. The BWG in group T5 was statistically similar to that of T2 fed diet and lower than that of control (T1). However, BWG in group T6 (200 mg vitamin E/kg) was higher than T2 and statistically similar to that of control group. Ochratoxin contamination in diet caused significant reduction in feed consumption, feed efficiency and livability percentage in broiler chickens. Addition of vitamin E (200 mg/kg) to the ochratoxin contaminated diet ameliorated the adverse effects on feed intake, FCR and livability percentage. Supplementation of vitamin E (200 mg/kg) to the ochratoxin contaminated diet also resulted in significant improvement in the relative weight of liver and bursa. It was concluded that experimentally induced ochratoxicosis with 200 ppb ochratoxin resulted in reduced production performance, enlargement of liver and regression of bursa. Addition of vitamin E (200 mg/kg) to the ochratoxin contaminated diet improved the production performance and relative weight of liver and bursa during 0–6 weeks of age of broiler chickens in experimentally induced ochratoxicosis caused by 200 ppb of dietary ochratoxin.

Apparent and standardised ileal digestibility of amino acids in wheat, triticale and barley for broiler chickens at two different ages

ABSTRACT1. The influence of the age of broiler chickens on ileal amino acid (AA) digestibilities in three cereals was examined. The digestibility estimates, including both apparent (AID) and standardised (SID) coefficients, for wheat, triticale and barley samples were determined using 14 and 28 d old broilers of mixed sex, fed diets containing the test grains as the only source of protein.2. Each assay diet was offered to five replicate cages of 14 and eight birds respectively, for the 14 and 28 day samplings. On both sampling days, the contents from the lower half of the ileum were collected for determination of the AID coefficients. The SID coefficients were calculated using ileal endogenous amino acid (EAA) losses previously determined from birds fed an N-free diet.3. The average AID for essential AA (EAA) in triticale and barley were significantly higher at 28 day compared to those at 14 days. In contrast, the magnitude of AID coefficients of AA in wheat was found to be in larger in the younger chickens.4. Correction of AID for EAA losses increased the values of digestibility coefficients by an average of about 7%. The SID values of AA in wheat was not influenced by the age of broilers. The SID of most AA in triticale, and of all the AA in barley, were higher in 28-day-old chickens compared with their 14-day-old counterparts. The results suggested that the SID coefficients of EAA in wheat determined at day 28 could be applied to feed formulations for 14-day-old broilers, but in the case of triticale and barley, the values obtained in older chickens were not applicable in younger birds and vice versa.

Active transport of glucose across the jejunal epithelium decreases with age in broiler chickens

Intestinal glucose absorption varies with growth; however, the dynamics of these variations has not been yet fully elucidated in broiler chickens. The present study aimed to compare jejunal glucose uptake and maltose digestion in broilers of 2 different ages, i.e., 1- vs. 5 wk old. Oral D-maltose gavage, everted sac, and Ussing chamber experiments were carried out to investigate intestinal glucose absorption and mRNA expression of glucose-transport-related genes as well as jejunal maltase activity. Upon gavage, glucose concentrations peaked at 10min post-administration in 1-wk-old chicks, while they peaked at 40min in 5-wk-old chickens. Glucose concentrations at 10min were significantly higher in the 1-wk-old chicks (P = 0.010). Using the everted sacs experimental setup, 5 intestinal regions i.e., duodenum, proximal jejunum, distal jejunum, proximal ileum, and distal ileum, were targeted to examine D-maltose digestion and glucose transport across the intestinal mucosa. In the distal and proximal ileum, glucose concentrations were found to be significantly higher in the serosal compartment of the 1-wk-old chicks upon incubation with D-maltose (25mM) (P < 0.05), while in the mucosal compartment the levels were significantly higher in the 5-wk-old chickens (P < 0.05). An Ussing chamber setup was employed to measure glucose-induced short-circuit current (ΔIsc) in the mucosal epithelium of the jejunum. In response to the addition of D-maltose (10mM) into the mucosal compartment, ΔIsc was significantly higher in the 1-wk-old chicks (P = 0.018). Furthermore, no variations in jejunal maltase activity were observed between the 2 age groups. While jejunal glucose absorption was lower in the 5-wk-old chickens, the mRNA expression levels of jejunal SGLT1, GLUT2, and Na+/K+-ATPase did not show any significant differences between the 2 age groups. Our results suggest that the active transport of glucose across the jejunal epithelium decreases upon growth in broiler chickens but is not accompanied by any variations in maltase activity or in the expression of glucose-absorption-related genes.

Effects of the biological age of broiler chickens and feed access after hatching on growth performance, serum biochemical parameters and intestinal morphology at slaughter age

Abstract The current study was designed to investigate the effects of the biological age (BA) of broiler chickens and feed access at hatching on growth performance, serum biochemical parameters, and intestinal morphology at slaughter age. A total of 720 chickens (Ross 308) were randomly allocated into 6 treatment groups as follows: 1–475Â h of BA with direct feed access, 2–475Â h of BA with delayed feed access, 3–489Â h of BA with direct feed access, 4–489Â h of BA with delayed feed access, 5–503Â h of BA with direct feed access, and 6–503Â h of BA with delayed feed access. The chickens at 489Â h of BA with direct feed access were found to be the heaviest with a value of 167.8Â g at 7 d of age, whereas a higher body weight was observed in chickens at 475 and 489Â h of BA with direct feed access with a value of 524.3Â g at 14 d of age. The highest body weight gain was found with a value of 2527Â g in broilers at 489Â h of BA with direct feed access. Broilers at 475Â h of BA with direct feed access had the worst FCR compared to the other groups. Small intestine morphological characteristics showed alterations for the duodenum, jejunum and ileum. The broilers at 489Â h of BA had a higher ratio of villus height and crypt depth than the broilers at 475 and 503Â h of BA. It resulted in a decreased turnover of the jejunum and ileum, which meant a lower maintenance demand and subsequently a higher body weight gain of broilers at 489Â h of BA with direct feed access. The present findings show that chickens at different BA (475, 489, and 503Â h) benefit from feed access in different ways, showing differences in body weight gain, feed efficiency, and small intestine morphological characteristics.

Effect of High Dietary Level of Some Amino acids and Coccidial Infection on Growth Performance and Health Status of Broiler Chicken

A total of 320 one-day-old Cobb chicks of mixed sex were used to investigate the impact of some amino acids supplementation and coccidial infection of broiler chicken on the growth performance, Immune response, some blood serum biochemical changes and intestinal morphology of broiler chickens. The chicks were randomly allotted into 10 equal groups, the first group were fed on the basal diet contain requirement of lysine (Ly), methionine (Met) and threonine (Thr) according to recommended catalog of the Cobb breed. Group 2 – 4 fed on the basal diet with 30% extra Ly, Met or Thr than recommended requirement respectively. Group 5 fed on the basal diet with extra combination of Ly, Met and Thr. Groups 6 – 10 fed on the same design as described for groups 1 – 5 with coccidial infection. It was found that the excess Ly, Met or Thr non-significantly increased the final body weight and significantly (P≤0.05) improved the feed efficiency and the performance index. Our data revealed that extra amino acids supplementation improved the blood picture and enhanced the immune response via increase the WBCs count and antibodies titer and significantly (P≤0.05) decreased blood serum carotenoids at 20th days of broiler age also reduced the coccidial fecal oocyst output at 14th or 28th days post-infection. It can be concluded that using of 30% extra methionine supplementation during the early age of broiler chickens and using 30% extra lysine supplementation during the grower and finisher period improved the performance and ameliorated the severity of coccidiosis.

Effect of Moringa (Moringa oleifera) Leaf Meal Supplementation in Broiler Chicken Ration on Weight of Internal Organs, HDL and Triglyceride Levels

This study aims to examine the effect of Moringa leaf meal on broiler chicken ration to the weight of internal organs, triglyceride levels and HDL. The material used in the study was 60 broiler chicken age 2 weeks strain CP707. The design used Completely Randomized Design (RAL) with five treatments and four replications in each treatment. The five treatments are 100% commercial rations without moringa leaf meal as control and 100% commercial rations with 3%, 6%, 9% and 12% moringa leaf meal. Parameters observed included, liver weight, gizzard weight, meat triglyceride levels, and HDL levels of meat. The data obtained were analyzed by completely randomized design. If among the treatments showed significant differences, then the study will be continued by Duncan's multiple-range test. From the results of this study it can be concluded that the addition of moringa leaf meal at level 10% in the ration is the optimal level to decrease the triglyceride of meat without disturbing the HDL content in the meat and the addition of moringa leaf meal up to 12% in the ration does not give a negative effect on the weight of internal organs.&#x0D; &#x0D; Keywords: Broiler Chickens, HDL, Internal Organ, Triglycerides

Response of broiler chickens fed diets supplemented with selenium during hotdry summer

In the process of understanding patho-physiology and developing packages for mitigation of heat stress during extreme summer (hot-dry) Selenium was tried individually in broiler pre-starter (0-14d), starter (14-21d) and finisher diets (21-42d of age) at four supplementary levels (0-control, 0.15, 0.3 and 0.45 mg/kg) during hot-dry (April-May, 29.0±0.700 to 36.0±1.400C, Rh,%: 61.0±1.3–70.1±0.82) conditions and the efficacy was judged through growth performance, carcass traits and feed-cost of production at 42nd day of age in broiler chickens. Therefore, total numbers of treatments were four. Each dietary treatment was fed to four replicated groups of 8 birds each. There was difference (P 0.05) due to dietary treatments during any growth phase. Supplementation of Se did not alter the yield of visceral organs and abdominal fat but supplemental Se increased (P<0.05) breast and eviscerated yields. Feed-cost per unit body weight gain or per kg meat yield did not differ statistically but numerically lower cost was incurred in Se supplemented groups than control.