Starter Diets Research Articles

Administration of Branched-Chain Amino Acids in the Pre- or Post-Hatch Period Improves the Fiber Characteristics of Pectoralis major Muscle in Turkey Poults Subjected to Early or Delayed Feeding

Poultry meat quality is controlled by muscle fiber properties associated with body weight gain in the immediate pre- or post-hatch period. This study aimed to determine the effect of administration of branched-chain amino acids blend (BCAAb, 3 L-leucine:1 L-isoleucine:2 L-valine) in the pre- or post-hatch period on the growth performance and fiber characteristics of the Pectoralis major (PM) muscle in turkey poults subjected to early or delayed feeding. Newly hatched poults from eggs injected in ovo with BCAAb or received no injection were used in a 21-d study. Poults (n=192) produced without injection of BCAAb received a starter diet supplemented (BCAA) or not (C) with the BCAAb (2 g/kg) immediately or with a delay of 48 h (48BCAA and 48C) after hatching. Poults (n=36) produced with (IOBCAA) in ovo injection of BCAAb (2 mg /ml) received the diet and water immediately. The BCAA and IOBCAA poults had higher body weight than those of the C, 48C, and 48BCAA birds. The body weight of the C poults was higher than those of the 48C and 48BCAA birds. The BCAA poults had higher PM muscle weight than those of the C and 48C poults, while that of the IOBCAA poults was higher than that of the 48C poults. The IOBCAA treatment increased the protein content of the PM muscle meat, compared with the C and 48C treatments. The 48C treatment increased the type IIB fiber area and the type I and type IIA fiber percentages but decreased the type IIB fiber, compared with other treatments. The numbers of type IIB and total fibers in the IOBCAA poults were higher than those of the 48C birds. In conclusion, administering BCAAb in ovo or in a starter diet enhanced early growth performance and improved the fiber characteristics of the PM muscle in turkey poults.

Effect of Different Water Quality with and Without Vitamin C on Some Physiological Parameters of Broiler Chickens

The current study was designed to investigate the effect of different water quality with and without vitamin C on some blood parameters and the relative weight of the heart, liver, gizzard, spleen and bursa gland of broiler chickens. A total of 252 one day old, unsexed chicks of broiler chicken (ROSS 308), average body weight 42 g were used in this study. The birds were randomly distributed into seven treatment groups (each group 36 birds), with three replicates per each (12 birds per replicate) based on completely randomized design for 35 days. The first group drank reverse osmosis (R.O) without any addition containing 28.16 total dissolved solids mg.l-1 (TDS), whereas the second, third and fourth groups drank water containing 1849.6, 1452.8 and 1356.8 TDS mg.l-l respectively. The fifth, sixth and seventh group drank water containing 1849.6, 1452.8 and 1356.8 TDS mg.l-1 with 100 mg.l-1 vitamin C respectively. The birds fed ad libitum a starter diet for 21 days and thereafter, on a grower diet. Increasing water TDS resulted in a significant increase in AST and ALT enzymes. On the other hand, increasing water TDS causing a decrease in the total protein and globulin. Addition vitamin C to different water quality causing a significant decrease in AST and ALT enzymes and increase in the total protein and globulin. Different water quality with or without vitamin C had no effect on albumin in serum and relative weight of heart, liver, gizzard and spleen. Increasing water TDS resulted in a significant increase in the relative weight of bursa gland. On the other hand, addition vitamin C to different water quality causing a significant decrease in the relative weight of bursa gland. It can be concluded that an increasing the level total dissolved solids (TDS) in broiler chickens drinking water caused stress for birds. The addition of vitamin C by 100 mg per liter led to a reduction in the stress of birds.

Dietary Addition of Black Cumin (Nigella Sativa) Seed on the Performance of Broiler Chicken during Summer Season

A experiment was conducted with a total number of 120 Cobb-400 strains of broilers were selected and subjected to four dietary treatments with 30 birds each having five replications per treatment. The birds of control group 1were offered standard broiler starter diet till 21 days and thereafter standard finisher diet up to 42 days. The birds of other groups were also offered the same diet as in group 1 along with black cumin seed powder supplementation at the rate of 1.0 (Group 2), 2.0 (Group 3) and 3.0 (Group 4) % of the diet. The values for average body weight, gain in weight, feed consumption,feed conversion efficiency, performance index and carcass weight per bird during the summer season had not shown any impact irrespective of treatments but it had significant (p<0.05) effect on haemoglobin, red blood cells, white blood cells, packed cell volume, low density lipoprotein, high density lipoprotein and Cholesterol. There was no mortality and hence liveability percentage was 100 % in all groups. The dressing percentage, carcass yield and organ weight was found to be best in treatment groups than control. The haematological and biochemical parameters were found to have positive effect in the treatment groups than control. However, the control group had the highest net profit return than treatment groups. Hence, it was concluded that using of black cumin seed as herbal feed additive helps in the improvement of health condition of the birds.

Preference of Broiler Chicken for Cassava-Moringa Based Diet

The poultry industry is under pressure from the rising cost of imported feed ingredients. In order for the industry to be profitable and sustainable, it has to reduce the cost of production by using locally available feedstuff. A study was carried out to evaluate feed preference of broiler chicken for cassava root chip, for three diets made by mixing different proportion in percentage of cassava root chip and ground Moringa leaf (90:10, 80:20, 70:30) and compare it to the preference for commercial starter diet. These diets were offered as free choice to five 20-days old chicken, one at a time over a period of five days. The three feed preference criteria assessed were (i) the visiting frequency to each diet station, (ii) time spent feed at each diet station, and (iii) amount of different treatment diet consumed. The hypothesis is that the preferred food will be visited more often; the chicken will spend longer time feeding on it and therefore consume it more. We found that broiler chicken consumed cassava root chip the least (2 g), visited it less often (9 visits) and spent less time (3.5 minutes) feeding on it. In contrast, feed consumption (6.12 g) and time spent (17 minutes) was highest for mixed diet containing 80% cassava and 20% Moringa leaf meal. Visiting frequency was highest for commercial starter diet (29 visits) and second highest (24 visits) for mixed diet of 80% cassava: 20% Moringa and 70% cassava: 30% Moringa. It is concluded that broiler chicken preferred the diet containing 80% cassava root chip and 20% Moringa leaf meal among all diets on offer.

Forage for Pre-weaning Calves: An Update

Forage nutrition for pre-weaning calves hosts numerous practical questions and on-farm challenges. The present review article aimed to update and address the biological consequences of forage provision to pre-weaned dairy calves. Health, nutrient intake (milk plus solid feed), and rumen development are the most important factors related to calf growth in pre- and post-weaning periods. A growing body of evidence suggests that the health and growth performance of dairy calves in the pre-weaning period are associated with their later performance as dairy cows. It seems that starter feeding strategies, including grain type, processing method, feed texture, and forage inclusion during the critical pre-weaning period may have profound effects on rumen function and calf performance. It is well understood that grain fermentation by-products are essential for increased growth and absorptive capacity of the rumen papillae. Forage provision as a part of a starter diet has been a topic of recent research. The rumen pH is the main factor altering the fate of fermentation and eventually animal health. In the pre-weaned calf, two major hypotheses exist regarding forage feeding. The first hypothesis describes that the rumen is not completely developed in pre-weaned calves and forage provision during this period might increase gut fill, and hence, decrease starter intake. It is believed that depressed starter intake may limit energy intake and finally suppress calf growth rate. The second hypothesis indicates that the rumen pH may decline as calves age and starter intake increases. Accordingly, forage inclusion in calf starter diets could prevent further rumen pH decline and subsequent negative consequences while improving starter intake and calf growth. Research data regarding these hypotheses are controversial. Many factors, such as milk feeding method, grain, forage type, and experimental conditions could affect calf responses to dietary forage. The current review focused on the biological consequence of forage provision to young calves to provide a practical framework for better use of forages in pre-weaned calves feeding programs. Keywords: Forage, Growth, Pre-weaned calf, Rumen development

Effect of using raw and treated quinoa seeds (Chenopodium quinoa) in the diets on some microbial, physical and chemical properties of broiler carcass

The experiment aimed to study the use of different proportions of raw and treated Chenopodium quinoa seeds by soaking in the diet in order to identify the effect in the physical and chemical traits of meat and the numbers of bacteria in the duodenum of 42 days of age. A 336 sexed broilers (Ross 308) were distributed randomly at one day old, with an average initial weight of 39 g/chick, divided into seven treatments, 48 ​​chicks/treatment, each treatment included three replicates, 16 chicks/replicate (8 males and 8 females). The chicks were fed on the starter diet (1-14) days of age, the grower diet of (15-28) days of age, and finisher diet (29-42) days of age, supplemented with raw quinoa seeds and treated by soaking as the first treatment (T1) was a control treatment without any addition. (T2) added 0.5% raw quinoa seeds, (T3) added 1% raw quinoa seeds, (T4) added 1.5% raw quinoa seeds, (T5) added 0.5% quinoa seeds treated with soaking, (T6) added 1% quinoa seeds treated with soaking, (T7) added 1. 5% quinoa seeds treated with soaking. The results showed a significant (P<0.05) increase in the average numbers of Lactobacillus bacteria in favor of treatments T4, T6, T7. In contrast, there was a significant decrease in the numbers of coliform bacteria in favor of the addition treatments T3, T4, T5, T6, and T7 compared to control treatment. As for the results of the physical traits, it achieved a significant decrease in the percentage of each of the drip loss and the weight lost when dissolve for all addition treatments, and in favor of the T4 treatment the percentage of loss during cooking and a significant increase in the water holding capacity in favor of all the addition treatments compared to the control treatment. As for the chemical properties, it was found that there was a significant increase in the pH values ​​and myoglobin pigment for meat in all the addition treatments compared to the control treatment (T1).

Effects of milk replacer allowances and levels of starch in pelleted starter on nutrient digestibility, whole gastrointestinal tract fermentation, and pH around weaning

The objectives of this study were to examine the effects of pelleted starter diets differing in starch and neutral detergent fiber (NDF) content when fed differing levels of milk replacer (MR) on nutrient digestibility, whole gastrointestinal tract fermentation, pH, and inflammatory markers in dairy calves around weaning. Calves were randomly assigned to 1 of 4 dietary treatments (n = 12 per treatment) in a 2 × 2 factorial design based on daily MR allowance and amount of starch in pelleted starter (SPS): 0.691 kg of MR per day [dry matter (DM) basis] with starter containing low or high starch (12.0% and 35.6% starch on DM basis, respectively), and 1.382 kg of MR per day (DM) with starter containing low or high starch. All calves were housed in individual pens with straw bedding until wk 5 when bedding was covered. Calves were fed MR twice daily (0700 and 1700 h) containing 24.5% crude protein (DM) and 19.8% fat (DM), and had access to pelleted starter (increased by 50 g/d if there were no refusals before weaning and then 200 g/d during and after weaning) and water starting on d 1. Calves arrived between 1 and 3 d of age and were enrolled into an 8-wk study, with calves undergoing step-down weaning during wk 7. Starting on d 35, an indwelling pH logger was inserted orally to monitor rumen pH until calves were dissected at the end of the study in wk 8. Higher SPS calves showed an increase in rumen pH magnitude (1.46 ± 0.07) compared with low SPS calves (1.16 ± 0.07), a decrease in rumen pH in wk 8 (high SPS: 5.37 ± 0.12; low SPS: 5.57 ± 0.12), and a decrease in haptoglobin in wk 8 (high SPS: 0.24 ± 0.06 g/L; low SPS: 0.49 ± 0.06 g/L). The majority of differences came from increased starter intake in general, which suggests that with completely pelleted starters the differences in starch and NDF do not elicit drastic changes in fermentation, subsequent end products, and any resulting inflammation in calves around weaning.

Comparative study of locally premix (its carrier Malva parviflora leaves meal) with imported premixes in diets on hematological bloodand Intestinal Microflora in broilers (Ross 308)

The study was carried out at the Animal Production Department, Faculty of Agriculture, University of Kufa to investigate the effect of feeding locally premixes comparable with imported premixes the broiler diets. Starter diets (23.3% C.P and 3021.0 kcal ME/kg) feed were gave to the birds from week 1 to week 3 of age, and finisher diets which contained 20.0% C.Pand 3204.0 kcal ME/kg were gave from 4thweek to 5th week of age. Five hundred seventy-six one day old Ross 308 chicks were randomly divided into eight groups with three replicate (24 bird /replicate)per group, Each group was subjected to the one of the following treatments: (T1)control contained 2.5% locally premix; (T2) 2.5%Provimi premix imported; (T3) 2.5%Turkish premixes imported; (T4) 2.5% Dutch premixes;(T5)1.25%locally+1.25%provimipremixes;(6)1.25%locally+1.25%Turkis;(7) 1.25%locally+1.25%Dutchpremixes;(8)0.625% from each one. Randomized Completely Block Design (RCBD) was used. Results showed that white blood cell, Hemoglobin, lymphocyte (L), Hetrophil (H) were improved significant (P≤0.05).The serum biochemical indices showed significant reductions values ofalkaline phosphatase(ALP),Aspartate aminotransferase (AST),phosphorus (P) compared with importedpremix.Harmful bacterial account were decreased significantly in local premix control. Additionally, beneficial bacteria were increased (p≤0.05) inlocal premix compared with imported. Based on the results obtained, the feeding of local premix(itscarrierMalva parviflora leavesmeal)2.5% of diet,the local premix gave promising results through the efficiency and ability that competed with the importer very strongly is recommended.

Exploring the functional and metabolic effects of adding garra fish meal to a plant-based broiler chicken diet.

The present study evaluated the metabolic and functional effects of adding garra meal to a broiler chicken diet. Three hundred twenty Sasso-breed day-old chicks were randomly assigned to four dietary treatments with either 0, 10, 20 or 30% garra meal added on top of formulated starter and grower basal diets. The experiment lasted for 42days. Feed intake and body weight gain increased at the starter and grower phases of broilers with garra meal addition (P < 0.05). Broiler chickens fed 30% garra meal were more efficient in converting feed to body weight and yielded the highest carcass weight (P < 0.05). Crude protein ileal digestibility coefficient was higher with 20% (76.2%), and crude fat with 20 (92.1) and 30% (92.6%) garra meal receiving groups (P < 0.05). The increase in individual and total esterified carnitine concentrations in dried blood spots demonstrated the elevated metabolic rate with garra meal addition (P < 0.05). A better supply of glucogenic substrate to the citric acid cycle was seen with garra meal addition due to the increase of propionylcarnitine to acetylcarnitine ratio (P < 0.05) without any apparent effect on ketogenesis in terms of serum 3-hydroxybutyrylcarnitine to acetylcarnitine ratio. Yet, it likely showed that part of the amino acids from garra meal were used as glucogenic substrate (P < 0.05). Histomorphometry data showed 20% garra meal addition elevated villus height, crypt depth and their ratio in the proximal parts of the small intestine (duodenum and jejunum) with the opposite results observed in the more distal part (ileum) with the highest for the control group (P < 0.05). It can be concluded that garra meal improved broiler performance when added to a plant-based diet and only few parameters warranted for caution when using more up to 30% garra meal addition. Beyond growth performance, garra meal generated a shift to a more efficient digestion, absorption and nutrient metabolism.

P47. Feeding low resistant protein content in starter diets reduced microbial protein fermentation and antibiotic treatment in weaned piglets

P47. Feeding low resistant protein content in starter diets reduced microbial protein fermentation and antibiotic treatment in weaned piglets

Effects of early feeding of enzymatically treated yeast on growth performance, organ weights, intestinal histomorphology, and ceca microbial metabolites in broiler chickens subjected to Eimeria challenge

The study evaluated effects of early feeding of enzymatically treated yeast on growth performance and selected physiological responses in broiler chickens. A total of 480-day-old (male) Ross × Ross 708 broiler chicks were placed in 24 floor pens (20 birds per pen) and allocated to 2 diets (control vs. yeast) in a completely randomized block design (n = 12). Diets were formulated for a 5-phase feeding program: Pre-starter; d 0 to 6 Starter; d 7 to 15, Grower: d 16 to 28, Finisher 1; d 28 to 42 and Finisher 2; d 43 to 56. The yeast was applied in pre-starter and starter diets at 0.6 and 0.2%, respectively. Birds received a common diet from d 16 to 56. Feed intake (FI) and body weight (BW) were recorded by phase for calculation of BW gain (BWG) and FCR. On d 10, all birds received an oral dose of 25,000 E. acervullina and 5,000 E. maxima sporulated oocysts in 1 mL of sterile saline. On d 15 post-hatch, one bird per pen was sacrificed for organ weights (gizzard, small intestine, ceca, liver, spleen, liver, and bursa), jejunal tissues for histomorphology and ceca digesta for microbial activity. On d 56, one bird per pen was sacrificed for organs and breast weight. In pre-starter phase, yeast fed birds showed improved (P < 0.05) BWG and FCR than control fed birds. Combining pre-starter and starter phases, the FCR of yeast fed birds showed improved FCR (1.115 vs. 1.135; P < 0.05) than control. The overall BWG (d 0–56) was 3.920 and 3.962 kg/ bird and corresponding values for FCR were, 1.808 and 1.755, for the control and yeast, respectively. Diets had no (P > 0.05) effects on physiological responses evaluated on necropsied birds except that yeast birds had (P < 0.05) lighter bursa than control birds on d 15. The current data indicated that yeast could support growth in early life of broiler chickens, but these effects were not sustained after the transitioning birds to common grower and finisher diets.

Early phase dietary supplementation of lipase and lecithin affects performance, haematology and immunology of broilers

A total of 192 one-day-old Ross 308 chicks were weighed individually (42.0 ± 0.8 g live weight) and randomly assigned to four dietary groups, each with three replicates of 16 birds. One group was a control (CON) and fed a starter diet without supplementation. The other three groups were fed the same starter diet during the starter phase (1 - 10 days old) supplemented with lecithin (LEC) at 0.05 g/kg diet or lipase (LIP) at 0.05 g/kg, or a combination (LEC+LIP) at 0.05 + 0.05 g/kg. No significant effects of supplementation with LEC and LIP on feed intake of broilers were observed during the starter phase, whereas bodyweight gain increased after the combined addition of these supplemental ingredients. Thus, final bodyweight was greater in LEC+LIP broilers compared with the other groups. Dietary supplementation with LEC or LIP had a positive effect on final bodyweight. However, the effect was less than the simultaneous supplementation of LEC+LIP. Moreover, the feed conversion ratio in the LEC+LIP group improved (P &lt;0.05) in the finisher phase (25 - 42 days old). Carcass traits and blood parameters were not influenced significantly by treatments, whereas supplementing LEC+LIP stimulated the immune system of broilers significantly. Thus, it can be concluded that supplementing LEC and LIP in early-stage broilers supported their performance and immune response positively up to finisher rearing phase.

Effects of sulfur amino acid supplementation on broiler chickens exposed to acute and chronic cyclic heat stress

Chronic heat stress can result in oxidative damage from increased reactive oxygen species. One proposed method to alleviate the chronic effects of HS is the supplementation of sulfur amino acids (SAA) which can be metabolized to glutathione, an important antioxidant. Therefore, the objective of this experiment was to determine the effects of dietary SAA content on broiler chickens exposed to HS from 28 to 35 d on broiler performance, body temperature, intestinal permeability, and oxidative status. Four experimental treatments were arranged as a 2 × 2 factorial consisting of HS (6 h at 33.3°C followed by 18 h at 27.8°C from 28 to 35 d of age) and Thermoneutral (TN- 22.2°C continuously from 28 to 35 d) and 2 dietary concentrations of SAA formulated at 100% (0.95, 0.87, and 0.80% for starter, grower, and finisher diets) or 130% SAA (1.24, 1.13, and 1.04% for starter, grower, and finisher diets). A total of 648-day-old, male Ross 708 chicks were placed in 36 pens with 18 chicks/pen and 9 replicates per treatment. Data were analyzed as a 2 × 2 factorial in JMP 14 (P ≤ 0.05). No interaction effects were observed on broiler live performance (P > 0.05). As expected, HS reduced BWG by 92 g and increased FCR by 11 points from 28 to 35 d of age compared to TN, respectively (P ≤ 0.05). The supplementation of SAA had no effect on live performance (P > 0.05). Cloacal temperatures were increased by 1.7, 1.4, and 1.2°C with HS at 28, 31, and 35 d compared to TN, respectively (P ≤ 0.05) and dietary SAA did not alter cloacal temperatures. At 28 d of age, supplementation of SAA to birds exposed to HS interacted as serum FITC-dextran (an indicator of intestinal permeability) was reduced to that of the TN group (P ≤ 0.05). The interaction was lost at 31 d, but HS still increased intestinal permeability (P ≤ 0.05). By 35 d, broilers were able to adapt to the HS conditions and intestinal permeability was unaffected (P > 0.05). Potential oxidative damage was reduced by increased SAA supplementation as indicated by an improvement in the reduced glutathione to oxidized glutathione ratio of 5 and 45 % at 28 (P = 0.08) and 35 d (P ≤ 0.05). These data suggest that intestinal permeability is compromised initially and to at least three d of heat exposure before the bird can adjust. However, oxidative damage in the liver of broilers exposed to HS is more chronic, building over the entire 7 d HS period and increased dietary SAA might have some protective effects on both broiler intestinal permeability and oxidative stress responses to HS.

Cereal type and combined xylanase/glucanase supplementation influence the cecal microbiota composition in broilers

Dietary fiber-degrading enzyme supplementation in broilers aims at off-setting the anti-nutritive effect of non-starch polysaccharides and at promoting broiler health. Recently, we demonstrated that xylanase/glucanase addition in wheat-based diet improved nutrient digestibility, arabinoxylan fermentability and broiler growth. Conversely, maize arabinoxylan was found to be recalcitrant to xylanase action. These findings suggested that enzyme-mediated improvement of nutrient digestion and carbohydrate fermentation depended on the cereal type present in the diet, and may have contributed to broiler growth. Hence, we aimed at further investigating the link between dietary enzymes and carbohydrate fermentation in broilers, by studying the impact of enzyme supplementation in cereal-based diets, to the microbial communities in the ileum and ceca of broilers. For that purpose, 96 one-day-old male broilers were randomly reared in two pens and received either wheat-based or maize-based starter and grower diets. At d 20, the broilers were randomly assigned to one out of four dietary treatments. The broilers received for 8 d the wheat-based or maize-based finisher diet as such (Control treatments; WC, MC) or supplemented with a xylanase/glucanase combination (Enzyme treatments; WE, ME). At d 28, samples from the digestive tract were collected, and the ileal and cecal microbiota composition was determined by 16S ribosomal RNA gene amplicon sequencing. A similar phylogenetic (alpha) diversity was observed among the four treatments, both in the ileal and the cecal samples. Furthermore, a similar microbial composition in the ileum (beta diversity) was observed, with lactobacilli being the predominant community for all treatments. In contrast, both cereal type and enzyme supplementation were found to influence cecal communities. The type of cereal (i.e., wheat or maize) explained 47% of the total variation in microbial composition in the ceca. Further stratifying the analysis per cereal type revealed differences in microbiota composition between WC and WE, but not between MC and ME. Furthermore, the prevalence of beneficial genera, such as Faecalibacterium and Blautia, in the ceca of broilers fed wheat-based diets coincided with arabinoxylan accumulation. These findings indicated that fermentable arabinoxylan and arabinoxylo-oligosaccharides released by dietary xylanase may play an important role in bacterial metabolism.

Effect of Graded Levels of Dietary Editan (Lasianthera africana) Leaf Meal on Productivity of Broiler Chickens

An experiment was conducted to determine the dietary effect of Editan ( Lasianthera africana ) leaf meal (ELM) on the growth performance and carcass characteristics of broiler chickens. One hundred and five (105) day-old unsexed Ross 308 broiler chicks were used in a 56-day feeding trial. There were five dietary treatments (T1, T2, T3, T4, T5) replicated three (3) times and each had seven (7) birds per replicate with a total of 21 birds per treatment in a completely randomized designed (CRD).T1 was the control diet which had no Editan leaf meal (0% ELM), T2 contained 1% Editan leaf meal, T3 contained 2% Editan leaf meal, T4 contained 3% Editan leaf meal and T5 contained 4% Editan leaf meal respectively. The Editan leaf meal was incorporated into starter and finisher diets. Feed and water were given ad libitum . Results showed that at the starter phase diets had no significant (P&gt;0.05) effect on all the parameters measured for growth performance. During the finisher phase, inclusion of Editan leaf meal up to 4% improved the final weight gain, total weight gain, daily weight gain, feed intake and feed gain ratio. Editan leaf meal up to 4% did not also show any negative effect on the breast, thigh wing, and drumstick and on the internal organs: gizzard, pancreas, heart, bile duct and large intestine. In conclusion, inclusion Editan N ( Lasianthera Africana) leaf meal up to 4%at both the starter and finisher phases showed positive influence on productivity of broilers and recommended. Keywords: Editan Leaf Meal; Growth performance; Internal Organs; Broiler Chickens DOI: 10.7176/JBAH/12-10-04 Publication date: May 31 st 2022

Abductive statistical methods improve the results of calibration curve bioassays: An example of determining zinc bioavailability in broiler chickens.

In this paper, we discuss the theory behind calibration curve experiments and their application to a zinc (Zn) bioavailability study with broiler chickens. Seven replicates of 16 male commercial broiler chicks were fed starter diets for 14 days. Six diets had different levels of a potential Zn source and one was a positive control with standard industry levels of Zn for comparison. Four commonly used methods of calculating bioavailability means and confidence intervals (CI) from a calibration curve (standard curve) experiment to estimate the bioavailability of a new zinc source in broiler chickens were compared. The methods compared were the following: 1) the Counter-Intuitive Method uses a multiple-range test to compare unknown test and standard samples; 2) the Intuitive Method uses standard linear regression and inverts the equation to predict Zn bioavailability for each replicate of test samples; 3) the Abductive Method uses Graybill's Equation, based on theory and observation, to estimate CI's; and 4) the Sophistic Method uses reverse regression, and calculates Zn bioavailability values directly from the equation. The Counter-Intuitive Method only gives information about which standards the test samples are, or are not, significantly different from respectively (average available Zn not predicted). The Intuitive Method ignores error about the standard curve and theoretically cannot estimate the CI directly ( = 107.5 ± 15.8 mg Zn/kg). The Sophistic Method underestimates and overestimates the test sample mean values above and below the mean of the standards, respectively ( = 96.6 mg Zn/kg). The Abductive Method has an advantage over the other methods: The mean prediction estimation is consistent with theory (107.5 ± 6.1 mg Zn/kg; ). When test or “unknown” samples are near the mean of the standard samples, the CI is smaller than when near the extremes of the calibration curve. When calibration curve error is small (R2 > approximately 0.95), there is little advantage to using the Abductive Method, but when calibration curve error is larger, as in many bioassays with growing animals, the Abductive Method improves the accuracy of the CI calculations. The Abductive Method was used to demonstrate the influence of the number of replicate samples on experimental power and cost.

Effect of β-Mannanase Supplementation on Growth Performance, Ileal Digestibility, Carcass Traits, Intestinal Morphology, and Meat Quality in Broilers Fed Low-ME Diets.

Simple Summaryβ-mannans, an example of non-starch polysaccharides, is one of the important anti-nutritional factors found in many leguminous feedstuffs used as raw material in poultry feed formulation. β-mannans bind to nutrients, reduce their bioavailability, and also increase the viscosity of intestinal digesta, which prevents the proper mixing of enzymes with digesta and affects the digestibility of nutrients. All these conditions ultimately reduce the growth performance of poultry birds. So, the objective of present study was to lower the effect of β-mannans by using β-mannanase in broiler diets. Results suggested that β-mannanase supplementation improved the intestinal morphology, which helped to increase the dry matter and crude fiber digestibility in broilers fed low energy diets. In addition, growth performance of broilers was not affected by reducing dietary energy levels with added β-mannanase than the Control group. Similarly, carcass traits were not affected by decreasing dietary energy levels with supplementation of β-mannanase. In conclusion, it could be stated that a low caloric diet with added β-mannanase had no negative effect on growth performance and carcass characteristics; however, it improved the dry matter and crude fiber digestibility.Experiment was designed to analyze the effect of low caloric diets, supplemented with β-mannanase on growth performance, carcass characteristics, nutrient digestibility, and other parameters in broilers. In this study, 400 broiler chicks were randomly divided into four treatments (Cont: without β-mannanase; LM-30, MM-60, and HM-90: supplemented with 200, 400, and 600 mg/kg β-mannanase, respectively). Dietary metabolizable energy (ME) in Cont was standard (starter diet 3100 kcal/kg; finisher diet 3200 kcal/kg) and reduced by 30, 60, and 90 kcal/kg, correspondingly in β-mannanase-supplemented treatments. The results exhibited that growth performance was not affected by reducing dietary energy levels with supplementation of β-mannanase. Ileal digestibility of DM and CF was improved (p < 0.01) by supplementation of β-mannanase at low dietary ME levels. Concerning carcass traits, the relative weight of breast meat, drumstick, and abdominal fat increased (p < 0.05) with β-mannanase supplementation in low-ME diets. Treatment HM-90 showed significantly (p < 0.05) better results regarding villus height and VH:CD. It could be concluded from the present results that supplementation of β-mannanase could improve the nutrient digestibility so that it is possible to reduce the dietary energy level without compromising production performance, carcass trails, and meat quality in broilers.

Evaluation of early feed access and algal extract on growth performance, organ development, gut microbiota and vaccine-induced antibody responses in broiler chickens

Hatching concepts such as on-farm hatching provide an opportunity to supply newly hatched chickens with optimal nutrition that support growth and development of a healthy gut. Brown algae contain bioactive compounds, especially laminarin and fucoidan that may improve intestinal health and immune responses. This study aimed to examine the effects of early access to feed and water posthatch and feed supplementation with algal extract rich in laminarin from Laminaria digitata, on growth performance, organ and microbiota development and antibody production. A total of 432 Ross 308 chicks were allotted to 36 rearing pens in a 2 × 3 factorial design with two hatching treatments and three dietary treatments. During chick placement, half of the pens were directly provided access to feed and water (Early) while half of the pens were deprived of feed and water for 38 h (Late). The chicks were fed three different starter diets until day 6; a wheat-soybean meal-based control diet, a diet with low inclusion of algal extract (0.057%) and a diet with high inclusion of algal extract (0.114%). Feed intake and BW were registered on pen basis at placement, days 1, 6, 12, 19, 26, 33 and 40. To induce antibody responses, all chicks were vaccinated against avian pneumovirus on day 10. Three chicks per pen were selected as focal animals and used for blood sampling on days 10 and 39. On days 6, 19, and 40, two birds per pen were killed and used for organ measurement and caecal digesta sampling for gut microbiota analysis using the Illumina Miseq PE 250 sequencing platform. Results showed that algal extract did not influence gut microbiota, gut development or vaccine-induced antibody responses. However, during the first 38 h, early-fed chicks consumed on average 19.6 g of feed and gained 27% in BW, while late-fed chicks lost 9.1% in BW which lowered BW and feed intake throughout the study (P < 0.05). Late chicks also had longer relative intestine, higher relative (g/kg BW) weight of gizzard and proventriculus but lower relative bursa weight on day 6 (P < 0.05). No effects of hatching treatment on microbiota or antibody response were detected. The microbiota was affected by age, where alpha diversity increased with age. In conclusion, this study showed that early access to feed but not algal extract improved the growth performance throughout the 40-day growing period, and stimulated early bursa development.

Effects of linseed oil supplementation in Holstein dairy calves received starters based on either corn or barley grain on growth performance and immune response.

This study evaluated the effects of linseed oil (LO) and two-grain sources on growth performance, microbial protein yield (MPY), blood metabolites, and inflammatory markers in Holstein dairy calves. Forty-eight 3-day-old dairy calves (24 males and 24 females) with starting BW of 40.3 ± 1.6 kg were allocated in a completely randomised block design with a 2 × 2 factorial arrangement as follows; (1) Corn grain (CG) with no LO supplementation (CG-NLO), (2) CG with 2.5% LO supplementation (CG-LO), (3) Barley grain (BG) with no LO supplementation (BG-NLO), and (4) BG with 2.5% LO supplementation (BG-LO). The calves were weaned on d 59 but the study lasted for 14 days after weaning (Day 73 of experiment). The results showed that starter feed intake was influenced neither by grain source nor linseed oil. However, average daily gain, BW, hip height, and MPY were improved in calves received BG compared to CG diets. Linseed oil supplementation had no significant effects on growth performance and MPY. During preweaning period, calves fed BG-LO had the greatest feed efficiency and the highest wither height. However, the greatest tumour necrosis factor and serum amyloid A were observed in BG-NLO. Despite, LO supplementation did not influence growth performance of animals per se; however, it reduced circulating inflammatory markers in calves during preweaning period. Based on this study condition, BG is more favourable than CG in dairy calves from the daily gain and microbial protein synthesis perspectives, and supplementing the starters with n-3 FA can be strategy to improve immune performance of calves fed barley-based starter diets.

49 Determining the Phosphorus Release of Grainzyme Phytase in Diets for Nursery Pigs

Abstract A total of 360 pigs (Line 200 × 400, DNA, Columbus, NE, initially 9.9 ± 0.19 kg) were used in a 21-d growth study to determine the available P (aP) release curve for GraINzyme phytase (Agrivida Inc., Woburn, MA). Pigs were weaned at approximately 21-d of age, randomly allotted to pens based on initial body weight (BW) and fed common starter diets. From d 18 to 21 post-weaning, all pigs were fed a diet containing 0.11% aP. On d 21 post-weaning, considered d 0 of the study, pens were blocked by BW and randomly allotted to 1 of 8 dietary treatments with 5 pigs/pen and 9 pens/treatment. Dietary treatments were formulated to include increasing aP derived from either an inorganic P source (0.11, 0.19, or 0.27% from monocalcium P) or increasing phytase (150, 250, 500, 1,000, or 1,500 FTU/kg). Diets were corn-soybean meal-based and contained 1.24% standardized ileal digestible (SID) Lys. On d 21 of the trial, 1 pig/pen (weighing closest to the mean pen BW) was euthanized and the right fibula was collected to determine bone ash using the non-defatted processing method. Overall (d 0 to 21), pigs fed increasing aP from inorganic P or phytase had increased (linear, P &amp;lt; 0.002) ADG, ADFI, and G:F (quadratic, P &amp;lt; 0.05). Bone ash weight (g) and percentage bone ash increased (linear, P &amp;lt; 0.001) with increasing inorganic P or added phytase. The release equations developed for GraINzyme for ADG, G:F, bone ash weight, and percentage bone ash are: aP = (0.255 × FTU) ÷ (1,299.969 + FTU), aP = (0.233 × FTU) ÷ (1,236.428 + FTU), aP = (45,999.949 × FTU) ÷ (462,529,200 + FTU), and aP = (0.272 × FTU) ÷ (2,576.581 + FTU), respectively.