Feed Conversion Ratio Of Broilers Research Articles

Effect of Metabolizable Energy and Crumble Quality of the Diet on Growth Performance of Broilers

In order to optimize the growth performance of broilers, diets are formulated to a recommended ME concentration. In addition, broilers (chicks) are often fed diets in the form of crumbles in early production to improve growth performance. Thus, the objective of this study was to determine the effect of ME concentration in diets and if removal of crumble fines influenced the growth performance response of broilers. At hatch, a total of 300 one-day-old male broilers (Cobb 500, initial BW 0.093 lb) were used in an 18-day study. Broilers were housed in 3 Petersime batteries with ad libitum access to feed and water. Treatments were randomly assigned to 60 cages balanced by location, resulting in 10 cages per treatment with 5 broilers per cage. Treatments were arranged in a 2 × 3 factorial of ME content (1,376 and 1,346 ME, kcal/lb) and crumbled diets with or without fines (removed particles < 1,532 µm or < 864 µm). Crumble treatments were fed with no sifting (NS) or sifted using either a screen with 0.06-in. openings (removed particles < 1,532 µm) or a screen with 0.03-in. openings (removed particles < 864 µm). Data were analyzed as a completely randomized design using the GLIMMIX procedure of SAS (v. 9.4, SAS Institute, Inc., Cary, NC). There was no evidence of an interaction between crumble fines removal and ME or main effect of ME. Body weight gain (BWG) and total feed intake (TFI) increased (P < 0.05) when broilers were fed crumbles sifted with a 0.06-in. screen compared to NS and crumbles sifted with a 0.03-in. screen. Broiler feed conversion ratio (FCR) improved (P < 0.001) when broilers were fed crumbles sifted with a 0.06-in. screen compared to those fed NS and sifted with a 0.03-in. screen. In conclusion, broilers fed crumbles with particles < 1,532 µm removed had an improved FCR and an increased BWG and TFI regardless of the ME content of the diet. Increasing ME from 1,346 to 1,376 kcal/lb did not influence growth performance of broilers from d 0 to 18 d of age.

Effect of novel natural feed additive containing Averrhoa bilimbi L. fruit filtrate, wheat bran, and Saccharomyces cerevisiae on growth performance and meat characteristics of broilers.

Background and Aim:In the post-antibiotic era, consumer demand for healthy and safe meats has prompted poultry producers to seek alternative effective feed additives. This study aimed to investigate the effects of a novel natural feed additive based on a mixture of Averrhoa bilimbi L. fruit filtrate, wheat bran, and Saccharomyces cerevisiae on the growth rate, internal organ weight, and breast meat characteristics of broilers.Materials and Methods:A total of 280 1-day-old chicks were divided into one control (CNTRL; feed without additives) and three treatment groups: NOV25, feed with 2.5 g/kg novel additive; NOV50, feed with 5.0 g/kg novel additive; and NOV100, feed with 10 g/kg novel additive. The body weight (BW), feed intake (FI), and feed conversion ratio (FCR) were measured weekly. On day 35, the chickens from each group were slaughtered, and their internal organs and breast meat samples were collected.Results:The BW of broilers in NOV100 was greater (p=0.016) than that in the other groups. The FCRs in the treatments groups were lower (p<0.001) than that in the control group. Elevated levels of the novel additive increased (p=0.051) the relative weight of the duodenum. The pH values in the breast meat of broilers receiving the novel additive were higher (p<0.001) than that in control. The C20:3n-6 of the NOV100 breast meat was lower (p=0.012) than that of NOV25 and NOV50, but it did not differ from that of the control. The unsaturated fatty acid-to-saturated fatty acid ratio in the breast meats of the treatments was higher (p=0.032) than that in control. The L-tyrosine content in NOV50 breast meat was higher (p=0.036) than that in CNTRL and NOV100 but did not differ from that in NOV25.Conclusion:The proposed feed additive improved the live BW and FCR of broilers and the physical and nutritional qualities of broiler breast meat.

Effect of Dietary Supplementation of Prebiotics, Synbiotics, and Essential Oils on Growth Performance of Broiler Chicken

This study was performed to compare the effect of dietary supplementation of probiotics, prebiotics, essential oils and synbiotics on feed conversion ratio, live body weight and total feed intake of broiler chicken. A total of 800, day-old Arbor acres broiler chicks of either sex were randomly assigned into four dietary treatments. Each treatment had four replicates of 50 birds and were reared for over five weeks. Basal diet was supplemented with probiotics (control, T1), essential oils (T2), synbiotics (T3), and prebiotics (T4) as dietary treatments. The birds were provided with ad libitum feed and drinking water during the entire experimental period. At the end of 35 days experimental period there was no significant difference in live body weight, total feed intake and feed conversion ratio of broilers fed prebiotic, synbiotic and essential oil groups compared with probiotic supplemented control group. These findings reveal that, there is a potential to use prebiotics, EOs, and synbiotics as non-antibiotic growth promoters to improve broiler chicken’s growth performances.

Dietary metabolizable energy, digestible lysine, available phosphorus levels and exogenous enzymes affect broiler chicken performance

The nutritional composition of diets and the provision of exogenous enzymes play important roles in animal performance. Here, we evaluated the individual and combined impact of nutrients (metabolizable energy (ME), digestible lysine (dLys), available phosphorus and calcium (avP–Ca)) and exogenous multicarbohydrase and phytase complex (MCPC) enyzmes on the growth performance and feed efficiency of broiler chickens from 10 to 42 days (d) of age. Experimental diets were formulated in a Box-Behnken design to contain various levels of ME (11.89, 12.21, 12.54 or 13.06 MJ/kg), dLys (0.91%, 0.93%, 0.96% or 1.00%) and avP/Ca (0.12/0.47%, 0.21/0.58% or 0.33/0.68%). The effect of MCPC was expressed in terms of the extra nutrients released. The diets were formulated to have consistent substrate contents (i.e., arabinoxylan and phytate). Feed intake (FI), BW gain (BWG) and feed conversion ratio (FCR) were described via polynomial equations (R2 = 0.99, 0.98 and 0.81, respectively), with interconnections between variables (ME, dLys and avP–Ca). Available P–Ca was the most important factor affecting FI (quadratically), and BWG and FCR (linearly). Reducing the avP content from 0.33% to 0.12% in diets lacking MCPC resulted in 25% and 33% decreases in FI and BWG, respectively, and a 12% increase in FCR. The ME and dLys contents also linearly affected these performance parameters to a lesser degree; FI decreased by 400 g when the ME was reduced by 1.17 MJ/kg, and by 300 g following a 0.09% reduction of dLys, while the same reductions in ME and dLys decreased BWG by 120 g and 150 g, respectively. The inclusion of MCPC alleviated the reduction of FI, BWG and FCR by decreasing the avP–Ca. Thus, ME and dLys were the most important factors affecting BWG and FCR in broilers fed diets containing MCPC. When MCPC was added, ME negatively affected FI (r = −0.89, P < 0.001), whereas the dLys content was correlated with BWG (r = 0.74, P < 0.001). Both ME and dLys affected FCR (r = −0.83 and −0.85, respectively). Supplementing MCPC allowed the reduction of ME, dLys and avP–Ca in the diet without affecting performance. Indeed, MCPC’s effect promoted with the release of the following nutrients: 0.56 MJ ME/kg, 0.06% dLys, and 0.15% and 0.13% avP and Ca, respectively. The results indicate nutrient effect and interaction on performance and feed additive potential for nutrient release.

Effects of dietary amino acid density and exogenous protease inclusion on growth performance and apparent ileal amino acid digestibility in poultry

Two experiments were conducted to evaluate the effects of dietary amino acid density and exogenous protease inclusion on growth performance and amino acid digestibility in poultry. In experiment 1, Cobb 500 broiler chicks (n = 480) were fed to 21 d of age. Treatments were arranged as a 2 × 4 factorial design with main effects of commercial protease (with or without) and amino acid density which corresponded to approximately 95, 97.5, 100, or 102.5% of breeder recommendations for digestible Lys. In experiment 2, hybrid turkey poults (n = 780) were fed diets formulated to provide low or adequate amino acid density (approximately 91 and 100% of the NRC-recommended requirement for digestible Lys, respectively) with each diet being fed with or without an exogenous protease. Poults received experimental diets from day 1 to 42 of age. Growth performance metrics were calculated from pen weights and feed consumption recorded throughout each experiment, and digestibility data were obtained from analysis of ileal contents. Data were analyzed using SAS 9.4 with pen as the experimental unit and pen location as the blocking factor. Results of these experiments demonstrated broilers fed 1.12 and 1.21% digestible Lys diets with added protease had a 2-point improvement in feed conversion ratio ( FCR ) compared with chicks fed these diets without protease. Increasing amino acid density improved FCR in broilers and poults and improved BW, ADG, and ADFI in poults. There was no evidence that added protease had an effect on BW, ADG, or ADFI in broilers or poults. Finally, ileal amino acid digestibility was not affected by amino acid density or protease inclusion for either 20-day-old broiler chicks or 42-day-old turkey poults.

The Laetiporus sulphureus Fermented Product Enhances the Antioxidant Status, Intestinal Tight Junction, and Morphology of Broiler Chickens.

Simple SummaryThis study investigated the effects of the Laetiporus sulphureus fermented product (FL) as a feed supplement on antioxidant activities, intestinal Tight Junction (TJ) mRNA expression, and the intestinal morphology of broiler chickens. FL supplementation could potentially enhance the feed conversion ratio in broilers by improving their antioxidative status, TJ mRNA expression, and intestinal morphology. Broilers supplemented with 5% FL exhibited the best overall results on improving antioxidant status, TJ mRNA expression, and intestinal morphology.The Laetiporus sp. is a fungal species that is traditionally used for medicinal purposes. This study investigated the effects of the Laetiporus sulphureus fermented product (FL) as a feed supplementation on the antioxidant activities, the intestinal Tight Junction (TJ) mRNA expression, and the intestinal morphology of broiler chickens. Four-hundred one-day-old male broilers (Ross 308) were randomly allocated to five experimental diets: (1) a corn-soybean meal basal diet (control), (2) a basal diet replaced with 5% Wheat Bran (5% WB), (3) a basal diet replaced with 10% WB (10% WB), (4) a basal diet replaced with 5% FL (5% FL), and (5) a basal diet replaced with 10% FL (10% FL). The FL-supplemented groups exhibited a better feed conversion ratio in the overall experimental period compared to the WB and control groups. The serum antioxidant profiles of 35-day-old broilers showed that, compared to the control and 10% WB groups, the 5% FL supplementation group had a significantly increased superoxide dismutase activity, while it down-regulated the concentration of malondialdehyde in the serum (p < 0.05). The assessment of selected antioxidant gene expression showed that the 5% FL group significantly elevated heme oxygenase-1 and nuclear factor erythroid 2–related factor 2 expression, compared to the control and WB groups (p < 0.05). Furthermore, both of the FL supplemented groups had a significantly higher expression of glutathione peroxidase and catalase, compared to that of the WB and control groups in the jejunum (p < 0.05). The TJ mRNA expression in the jejunum showed that 5% FL significantly elevated the zonula occludens-1, claudin-1, and mucin-2 expression (p < 0.05), while 5% and 10% FL supplementation significantly improved OCLN expression in both the jejunum and ileum, compared to control group (p < 0.05). The intestinal morphology of 35-day-old broilers showed that a 5% FL supplementation significantly increased the villus height in the ileum and jejunum, compared to the WB and control groups (p < 0.05). Moreover, the 5% and 10% FL supplementation groups had a significantly higher villi:crypt ratio in the ileum, compared to the WB and control groups (p < 0.05). To conclude, FL supplementation improved the antioxidative status, the TJ mRNA expression, and the intestinal morphology, and it was accompanied by a lowered feed conversion ratio in broilers. Finally, 5% supplementation had the overall best results in improving the antioxidant status, TJ mRNA expression, and intestinal morphology of broilers.

Effects of ND vaccination combined LPS on growth performance, antioxidant performance and lipid metabolism of broiler

Newcastle Disease Virus (NDV) is the important pathogen of Newcastle Disease (ND) attacking chicken, turkey and other birds. Therefore, the purpose of this study was to assess the effects of immune stress induced by ND vaccination and lipopolysaccharide (LPS) on growth performance, antioxidant ability, and lipid metabolism of broilers. In total, 128 one-day-old broilers were randomly assigned to the following four groups and were treated as indicated: normal control (NC); vaccinated with live LaSota ND vaccine (CV); administered ND vaccine and 0.25 mg/kg body weight (BW) LPS (L-LPS); and administered ND vaccine and 0.5 mg/kg BW LPS (H-LPS). The results demonstrated that broiler feed conversion ratio (FCR) was increased in the groups CV, L-LPS and H-LPS from d 0 to 42 days compared with the group NC. The antioxidant function of broilers was decreased as indicated by the malondialdehyde (MDA) and glutathione peroxidase (GSH-Px) levels in the serum of the treated groups. ND vaccination combined LPS increased the concentration of total cholesterol (TC), triglyceride (TG) and low-density lipoprotein cholesterol (LDL-C), but decreased the concentration of high-density lipoprotein cholesterol (HDLC) compared with the group NC. The reverse transcription (RT)-PCR results revealed that the mRNA expression of acetyl-CoA carboxylase gene (ACC) and 3-hydroxy-3-methylglutaryl coenzyme-A reductase (HMGR) in the liver were downregulated, whereas the mRNA expression of carnitine palmitoyltransferase-1 (CPT-1) and peroxisome proliferator-activated receptor (PPAR)-α were upregulated compared with the group NC. These results suggest that ND vaccination combined LPS reduced broiler growth performance and antioxidant ability, whereas it activated AMPK-mediated lipid metabolism.

Effects of replacing dietary Aureomycin with a combination of plant essential oils on production performance and gastrointestinal health of broilers

The objective of this study was to investigate the effects of replacing antibiotics with a combination of plant essential oils on the growth performances and gastrointestinal health of broilers. A total of 720 1-day-old male AA broilers were randomly divided into 3 treatments: the control treatment (CON), the Aureomycin supplementation treatment (AGP), and the combined plant oils supplementation treatment (POC), with a 42-D period feeding procedure. Growth performances, carcass performances, intestinal sections, and cecal microbiota were investigated. Results indicated that POC supplementation decreased the feed conversion ratio compared with CON and AGP treatments, though not significantly. No significant differences were found for feed intake, BW gain, and culling rate among the 3 treatments (P > 0.05). In addition, no significant differences were seen on carcass performance. For the aspects of intestinal section, POC supplementation did not make significant effects on intestinal wall thickness, villus heights, crypt depths, and the ratio of villus heights/crypt depths compared with CON and AGP treatments. Cecal microbiota results demonstrated that bacterial diversity and some representative probiotic bacteria were significantly increased in numbers (P < 0.05) after POC supplementation. In conclusion, the combination of essential oils promoted intestinal health through improving gut bacterial diversity and probiotic bacteria, as well as improving feed conversion ratio of broilers. These results indicated that the combination of essential oils may benefit the gastrointestinal health and be applied as an antibiotic alternative.

Efficacy of dietary supplemental insoluble fibrous materials in ameliorating adverse effects of coccidial challenge in broiler chickens

ABSTRACT The current experiment was designed to examine effects of dietary supplemental sunflower hulls (SH) and rice hulls (RH) on growth performance, carcass traits, intestinal morphology, lesion score and oocyst shedding in broiler chickens exposed to coccidial challenge. A total of 540 broiler chickens (Ross 308) were assigned to six dietary treatments based on a factorial arrangement (2 × 3) across 1–14, 14–28 and 28-42-d periods. Experimental treatments consisted of broiler chickens without or with coccidial challenge each offered with three different diets: a basal diet or basal diet supplemented with either RH or SH at 40 g/kg diet, respectively. Infection with Eimeria impaired daily weight gain (DWG) and feed conversion ratio (FCR) of broiler chickens during growing period (p < 0.05) while supplementation of SH or RH reduced the adverse effect of coccidiosis so that birds had similar DWG to those fed the basal diet without infection. However, only dietary SH improved the FCR of broilers challenged with coccidiosis. Regardless of coccidial challenge, dietary access to insoluble fibre improved performance of broilers across the growing period (p < 0.05); however, this effect was not observed during the entire rearing period. Relative weights of liver and pancreas were increased in birds subjected to coccidial challenge on d 21 of age (p < 0.05). Moreover, relative weights of the intestinal segments were enhanced (p < 0.05). Furthermore, gizzard weights were higher in birds receiving diets added with fibre (p < 0.05). Infection with coccidiosis decreased villus height and villus height to crypt depth ratio in duodenum of broilers which received the basal diet compared with those fed the same feed without coccidial challenge (p < 0.05). However, supplemental SH could decrease the negative effect of infection on the noted intestinal morphometric attributes. Similarly, a marked reduction was observed for lesion score and faecal oocyst excretion of challenged broilers fed on dietary supplemental fibre (p < 0.05). In conclusion, supplementation of insoluble fibre could ameliorate negative effects of coccidial challenge on DWG of broiler chickens and inclusion of SH in diet of birds exposed to Eimeria infection could be recommended.

Influence of Dietary Multiple Phase Feeding on Growth Performance of Commercial Broiler Chicken

The experimental trial was carried out to study the effect of multiple phase feeding on the growth performances and the economics of broiler production for a period of six weeks. Day-old chicks (n=160) were divided into two treatment groups, each containing 80 chicks with four replicates in each treatment. The birds of the control group (A) were fed prestarter, starter and finisher diets as per nutrient requirement of commercial broiler strain used in the experiment and the multiple phase feeding was followed in group-B by changing the nutrient densities (Energy, Crude protein, lysine and methionine) of diet per week. The different performance parameters were studied such as live body weight, gain in live body weight, feed conversion ratio and feed consumption at weekly interval. Mortality was recorded daily and the economics was calculated at the end of experiment. The results of experiment showed that the body weight and weight gain of broilers of group-B was significantly higher (p less than 0.05) than that of broilers of group-A during first, second, fifth and sixth week of age and also during overall duration of the experiment. Further, the feed intake of broilers of group-B was significantly higher (p less than 0.05) than that of group-A during second, fifth and sixth weeks of age and also during the overall feed intake of broilers. The Feed Conversion Ratio of broilers of group-B was significantly better (p less than 0.05) than that of group-A during fifth week and also during the overall performance. The multiple phase feeding has not put any adverse effect on percentage mortality of broilers. However, broilers fed with the multiple phase feeding showed higher net profit per bird and also per kg of body weight as compared to the broilers of control group (A).

Feeding high-oleic peanuts to meat-type broiler chickens enhances the fatty acid profile of the meat produced

Early feeding trials using peanut meal prepared from normal-oleic peanuts helped to identify peanuts as a suitable alternative feed ingredient for poultry. Yet no studies to date have examined the use of high-oleic peanuts (HO-PN) as a feed ingredient for meat type chickens. Therefore, this study aimed to determine the effect of feeding whole unblanched HO-PN on the fatty acid profile of the meat produced from broilers. At hatch male chicks were randomly placed in raised wire cages, in 10 replicate pens per treatment with 10 chicks per pen, and fed with one of the 3 isocaloric, isonitrogenous diets ad libitum for 42 days: (1) conventional control of soybean meal + corn, (2) 10 to 12% HO-PN and corn diet, or (3) control diet spiked with ≈6.0% oleic acid oil. All body weights (BW) were collected, and broiler selection for processing was determined by individual BW within one-half a standard deviation of the experiment 42-D mean BW, with one bird selected per pen (10 replicate pens per treatment, 3 treatments, 10 birds selected per treatment, yielding a total sample size of 30 birds). Performance was determined weekly and breast samples were analyzed for fatty acid and amino acid profile. All data was analyzed using analysis of variance, with t-test mean comparisons at P < 0.05. BW were similar between broilers fed the HO-PN and control diet, while feed conversion ratio of broilers fed the HO-PN diet was significantly higher at weeks 2, 4, and 6 in comparison to the other treatments (P ≤ 0.03). Broilers fed with HO-PN diet had reduced carcass and pectoralis major weights in comparison to the other treatments. Chicken breast from broilers fed the HO-PN diet had significantly reduced saturated and trans fatty acid content in comparison to the controls (P ≤ 0.0002). Although additional studies must be conducted, this study suggests that feeding whole unblanched HO-PN to broiler chickens may serve as a means to enrich the meat produced with unsaturated fatty acids.

Response of broilers to supplementation of branched-chain amino acids blends with different valine contents in the starter period under summer conditions.

ObjectiveThe objectives of this study were to compare the effects of normal and low protein content (PC) of starter diet supplemented or not with blends of branched-chain amino acids (BCAAs) on growth performance of broilers under summer conditions and to investigate whether these effects altered some quality traits and the characteristics of gastrointestinal tract.MethodsA total of 768 mixed-sex broiler chicks (Ross 308, one-d-old) with an average initial body weight (BW) of 47.6±1.03 g were allocated into six treatments with four replications in 2×3 factorial arrangement. Factors were: PC, normal (N, 22% to d 15); and low (L, 20% to d 15); and added BCAA blends, L-leucine, L-isoleucine, and L-valine at zero (0L:0I:0V); 1.0, 0.25, and 0.25 (4L:1I:1V); or 1.0, 0.25, 0.75 (4L:1I:3V) g/kg of diet. Hence, six dietary treatments were named as N0L:0I:0V, N4L:1I:1V, N4L:1I:3V, L0L:0I:0V, L4L:1I:1V, and L4L:1I:3V. Average indoor temperature and humidity were 32.8°C±1.7°C and 61.1% ±4.12%, respectively.ResultsBW, feed conversion ratio (FCR) and carcass weight were not affected by PC, BCCA and their interaction (p>0.05). The L diets decreased the water holding capacity of the breast (p = 0.002) and thigh (p = 0.050) meats and dressing percentage (p = 0.005) compared to the N diets. The 4L:1I:1V diet decreased breast yield compared to the 0L:0I:0V diets (p = 0.041). The effect of PC on feed intake, mortality and gastrointestinal trait weight were depended on the L:I:V ratios under summer conditions due to interactions between factors (p<0.05). The FI and mortality of L4L:1I:1V broilers were lower than those of N4L:1I:1V birds (p<0.05).ConclusionIt was concluded that the blends of BCAAs used failed to improve performance and to promote breast yields, because diets with normal or with reduced protein supplemented or not with BCAAs up to d 15 produced a similar BW and FCR in broilers raised in hot-climate conditions.

Effects of gingerols-rich extract of ginger on growth performance, serum metabolites, meat quality and antioxidant activity of heat-stressed broilers.

In order to investigate the effects of dietary ginger extract (GE) enriched in gingerols on broilers under heat stress (HS) from 21 to 42 days of age, a total of 144 Ross 308 male broilers were randomly allocated to three groups with six replicates of eight broilers per replicate. Broilers in the control group were raised at 22°C and fed a basal diet, and broilers in the other two groups were raised under cyclic HS (34°C from 9:00 to 17:00 and at 22°C for the rest of the time) and fed the basal diet with or without 1000mg/kg GE. Supplementation of GE improved (P<0.05) final body weight, average daily gain and feed conversion ratio of broilers under HS, and tended (P<0.1) to increase breast muscle yield. The alterations of serum total protein, albumin, total cholesterol levels and aspartate aminotransferase activity under HS were reversed (P<0.05) by GE, which also decreased (P<0.05) serum triglyceride level and alanine aminotransferase activity. The decreased redness (a* value) and increased drip loss of breast muscle induced by HS were restored (P<0.05) by GE. Moreover, GE supplementation increased (P<0.05) total antioxidant capacity and decreased (P<0.05) malondialdehyde content in liver and breast muscle, and increased (P<0.05) glutathione peroxidase activity in serum and breast muscle. In conclusion, dietary GE supplementation restored growth performance, serum metabolites and meat quality of broilers under HS possibly by improving antioxidant activity.

Comparative aspects of phytase and xylanase effects on performance, mineral digestibility, and ileal phytate degradation in broilers and turkeys

Two experiments were performed, using broilers or turkeys, each utilizing a 3 × 2 factorial arrangement, to compare their response to phytase and xylanase supplementation with growth performance, nutrient digestibility, and ileal phytate degradation as response criteria. For both experiments, 960 Ross 308 or 960 BUT 10 (0-day-old) birds were allocated to 6 treatments: (1) control diet, containing phytase at 500 FTU/kg; (2) the control diet with xylanase (16,000 BXU/kg); (3) the control diet supplemented on top with phytase (1,500 FTU/kg); (4) diet supplemented with 1,500 FTU/kg phytase and xylanase (16,000 BXU/kg); (5) the control diet supplemented with phytase (3,000 FTU/kg); and (6) diet supplemented with 3,000 FTU/kg phytase and xylanase (16,000 BXU/kg). Each treatment had 8 replicates of 20 birds each. Water and diets based on wheat, soybean meal, oilseed rape meal, and barley were available ad libitum. Body weight gain and feed intake were measured from 0 to 28 D, and feed conversion ratio (FCR) corrected for mortality was calculated. Ileal digestibility for dry matter and minerals on day 7 and 28 were analyzed in addition to levels of inositol phosphate esters (InsP6-3) and myo-inositol. Statistical comparisons were performed using ANOVA. Xylanase supplementation improved 28D FCR in broilers and turkeys. Increasing doses of phytase reduced FI and improved FCR only in broilers. In broilers, the age × phytase interaction for phosphorous digestibility showed that increasing phytase dose was more visible on day 7, than on day 28. Mineral digestibility was lower in 28-day-old turkey compared with 7-day-old turkey. InsP6 disappearance increased with increasing phytase levels in both species, with lower levels analyzed in turkeys. InsP6 disappearance was greater in younger turkeys (day 7 compared with day 28). In conclusion, although broilers and turkeys shared several similarities in their growth and nutrient utilization responses, the outcomes of the 2 trials also differed in many aspects. Whether this is because of difference in diets (InsP or Ca level) or differences between species needs further investigation.

Effects of Elevated Platform and Robotic Vehicle on Broiler Production, Welfare, and Housing Environment

HighlightsUsing an elevated platform with a manure catcher reduced litter moisture content and ammonia concentration.A robotic vehicle encouraged bird movement and use of the elevated platform.Using the elevated platform and robotic vehicle jointly improved broiler paw quality and plumage cleanliness.Abstract. Elevated platform (EP) and robotic vehicle (RV) are two emerging systems aiming to improve environment enrichment and bird activity in broiler housing systems. However, the impacts of these systems on broiler production, welfare, and housing environment have not been evaluated. The objective of this study was to evaluate the effects of using EP and RV individually or jointly on broiler feed conversion ratio (FCR), litter moisture content (LMC), ammonia (NH3) concentration, gait score (GS), paw quality (PQ), plumage cleanliness (PC), and bird activity index (AI). Broilers were reared for eight-week production cycles. Four experimental rooms (54 birds room-1) were randomly assigned four treatments: EP only, RV only, EP and RV (EP+RV), and neither EP nor RV (Ctrl). Broiler GS, PQ, and PC were assessed following welfare protocols. Bird AI was determined through image processing. The experiment was repeated three times. The results showed that overall FCR values were 1.806 for EP, 1.804 for RV, 1.797 for EP+RV, and 1.791 for Ctrl. The normalized LMC values were 23.2% ±4.1% for EP, 32.8% ±4.1% for RV, 23.4% ±2.5% for EP+RV, and 35.7% ±7.0% for Ctrl over the eight-week production cycles. NH3 concentrations were 40% lower in the rooms with EP than in the rooms without EP at the end of the production cycle. Broilers had better PQ in the rooms with EP than in the rooms without EP. Broiler PC seemed better in the rooms with RV compared to those without RV. Operation of RV increased bird AI; however, the benefits in activity encouragement diminished as the broilers grew. The number of broilers on the EP was higher in the EP+RV rooms than in the EP rooms. It is concluded that using EP and RV together may improve broiler welfare and activity without compromising their production performance. Keywords: Behavior, Broiler, Elevated platform, Robotic vehicle, Welfare.

The length of the feed restriction period affects eating behavior, growth performance, and the development of the proximal part of the gastrointestinal tract of young broilers

We studied the effects of restricting the access to feed on the anticipatory eating behavior, growth performance, and the development of the proximal part of the gastrointestinal tract (GIT) in broilers. The experiment consisted in physical restriction of the access of broilers to feed for 0, 4, 6, or 8 h per day from 7 to 19 D of age. At 10, 13, 16, and 19 D of age, immediately before the start of the feed restriction (FR) period, 2 birds per cage were euthanized to evaluate crop and gizzard development. The experimental design was completely randomized, and the linear (L) and quadratic (Q) effects of fasting length on growth performance and GIT traits were determined. In addition, the effect of broiler age on GIT development was studied. From 7 to 19 D of age, ADFI (L, Q; P ≤ 0.05) and BW gain (L; P ≤ 0.01) decreased as the length of the FR period increased, with most of the differences observed with 6 or more hours of fasting. However, feed conversion ratio was not affected by FR length. The relative weight of the crop (% BW) and its fresh content increased (L; P ≤ 0.001) and the moisture of the digesta (%) decreased (L; P ≤ 0.001) as the FR period increased. The DM content (g) of the crop increased with FR, with most of the differences observed with 6 or more hours of fasting (L, Q; P ≤ 0.001). At 19 D of age, the Lactobacillus spp. count in the crop increased (L; P ≤ 0.05) with increase in the FR period. Fasting did not affect any gizzard trait at any age. In summary, physical restriction of the access to feed for 6 h or more reduced BW gain but did not affect feed conversion ratio in broilers from 7 to 19 D of age. Feed restriction for 4 to 8 h stimulated the anticipatory feeding behavior and crop development in broilers.

Growth Performance of Broilers as Influenced by Different Levels and Sources of Methionine Plus Cysteine

Simple SummaryThe current work evaluated the utilization of different sources of methionine either from DL-methionine (DL-Met) or L-methionine (L-Met) using different concentrations of dietary methionine plus cystine (Met + Cyst) in broiler chickens. Results showed that a better edible meat yield could be obtained by supplementing Met + Cyst at the rate of 80% of the digestible lysine.The objective of this work was to evaluate the utilization of methionine from DL-methionine (DL-Met) and L-methionine (L-Met) with different levels of dietary methionine plus cystine (Met + Cyst) in broilers. The experimental diets were formulated by using three levels of Met + Cyst, i.e., 74%, 77% and 80% of digestible lysine. Met + Cyst was provided either from DL-Met or L-Met. A total of 450 day-old broilers were divided into six groups (five replicates of 15 birds each) in a 3 × 2 factorial arrangement under completely randomized design. Weight gain (WG), feed intake (FI) and feed conversion ratio (FCR) was determined. At the end of the experiment (35 days), two birds from each replicate were slaughtered to determine carcass characteristics and serum homocysteine. Results indicate that the combined effect of L-Met and DL-Met significantly affected (p < 0.05) the WG in the starter period and FI in the finisher period. Neither source nor level of methionine influenced (p > 0.05) the FI, WG and FCR of broilers during the starter, finisher or overall phase of growth. The interaction between sources and levels of methionine did not influence (p > 0.05) the feed intake, weight gain and FCR during the overall phase of growth. Source of methionine had no (p > 0.05) effect on carcass characteristics. Methionine levels had a significant effect (p < 0.05) on carcass weight, chest weight and thigh weight. The interaction between sources and levels of methionine had a significant (p < 0.05) effect on the liver weight. The sources of methionine had significant (p < 0.05) effects on the liver and heart weight, while methionine levels significantly influenced (p < 0.05) the liver and gizzard weight. Finally, it was concluded that if DL-Met and L-Met are included in feed at a standard level, they are equally effective as a source of methionine for broilers.

Effects of yeast cultures with different fermentation times on the growth performance, caecal microbial community and metabolite profile of broilers.

The objective of this study was to investigate the effects of yeast culture (YC) on the growth performance, caecal microbial community and metabolic profile of broilers. A total of 350 1-day-old healthy Arbor Acres broilers were randomly assigned to seven treatment groups. The first group received a basal diet without YC supplementation, whereas the remaining groups received a basal diet supplemented with either YC fermented for 12, 24, 36, 48 or 60hr, or a commercial YC product (SZ2). MiSeq 16S rRNA high-throughput sequencing was used to investigate the bacterial community structure, and gas chromatography-mass spectrometry was used to identify the metabolites in the caeca of broilers. The broilers that received a diet supplemented with YC had a higher average daily gain and average daily feed intake than those received YC-free or SZ2-enriched diets. The feed conversion ratio (FCR) of YCs fermented for 24hr resulted in the best feed efficiency, whereas the FCR of YC fermented for 60hr resulted in poor feed efficiency (p<.05). In the caeca of broilers, the bacterial communities were well separated, as determined by principal component analysis, and the proportions of the eight genera were significantly different among the seven groups (p<.05). The genus Akkermansia was the most abundant when the diet supplemented with YC fermented for 24hr (p<.05). Furthermore, the Firmicutes/Bacteroidetes ratio was positively correlated with the FCR in the caecum (r=.47, p<.005). Five differentially expressed metabolites (i.e., L-alanine, benzeneacetic acid, D-mannose, D-arabitol and cholesterol) were identified in the caeca of broilers that received diets supplemented with YCs fermented for 24 or 60hr. In summary, the different fermentation times of the YCs can markedly improve the growth performance and FCR of broilers by altering the caecal microbial community, and the growth performance which is related to the changes in key metabolic pathways.

Effects of Colombian oregano essential oil (Lippia origanoides Kunth) and Eimeria species on broiler production and cecal microbiota

The gut microbiota has an important effect on poultry health and production. The aim of this study was to evaluate the effect of Colombianoregano (COO), Lippia origanoidesKunth, essential oil supplementation on broiler chicken performance and their cecal bacterial microbiome by 16S-based sequencing. Essential oil was extracted by steam distillation and analyzed by Gas chromatography/mass spectrometry. Two COO levels in feed, 0 ppm control (C) and 100 ppm (O), were evaluated in 2 groups of broilers either unchallenged (U) or challenged (E) with a viable attenuated Eimeria (coccidia) oocytevaccine. Four treatments, UC, UO, EC, and EO, were distributed among 720 one-day-old male Ross broilers randomly placed in 24 pens. Cecal contents DNA was extracted and pyrosequencing was performed following a standard procedure. Pyrosequencing data were processed, and sequence reads were phylogenetically classified. Similarity of membership and structure in the communities were calculated.At the end of the study, the greatest COO effect was found in coccidia-challenged broilers, with an OE body weight of 1,889 ± 52.4 g with respect to 1,799 ± 36.2 g for CE (P < 0.01). Broiler cecal samples were consistent in that phylum Firmicutes and class Clostridia were highly prevalent; COO had no effect on these taxa levels between the 4 treatments (P > 0.05). A positive correlation (P < 0.01) was observed between the Firmicutes:Bacteriodetes phyla ratio against body weight at 35 D of age. This study provided both positive and negative correlations between broiler body weight against some bacterial groups identified, offering perspectives regarding bacterial groups and their impact on host health and metabolism. Lippia origanoides Kunth high thymol content showed a beneficial effect on body weight and the feed conversion ratio in broilers under coccidia challenge.

Dietary Supplementation with Lysine and Threonine Modulates the Performance and Plasma Metabolites of Broiler Chicken.

Here, we investigated whether the optimal threonine (Thr) to lysine (Lys) ratio in high Lys diet improves the growth performance of modern broiler chickens at finisher period and determined the possible mechanism underlying improvement in the growth performance of chickens fed with high Lys or Lys + Thr diet using metabolome analyses. Eighteen 21-day-old chickens housed in individual cages were randomly divided into three groups of six chickens fed with different diets as follows: control diet, high Lys diet (150% Lys content of National Research Council requirement), and high Lys + Thr diet (0.68 of Thr/Lys in high Lys diet). Body weight gain (BWG) increased in chickens receiving high Lys diet as compared with those fed with the control diet (P<0.05); no significant difference was observed in BWG of chickens from high Lys + Thr and high Lys groups. Feed conversion ratio (FCR) was lower in chickens fed with high Lys or high Lys + Thr diet than in those on the control diet. Serotonin concentration increased in the plasma of chickens fed with high Lys diet as compared to those fed with other diets. A negative correlation was observed between plasma serotonin concentration and FCR. These results provide the first evidence on the use of high Lys in broiler diets to reduce FCR during finisher period, which may be associated with change in plasma serotonin concentration. These findings suggest that high Lys content in finisher diet, but not high Thr + Lys diet, may affect the peripheral serotonergic metabolism and improve FCR. Thus, plasma serotonin may serve as a biomarker of FCR in broilers.