High Nutrient Density Diet Research Articles

Effects of spray-dried plasma on performance, carcass parameters, tibia quality and Newcastle disease vaccine efficacy in broiler chicken fed corn-soy diets with two varying levels of digestible amino acids and AMEn density.

This study aimed to determine the effects of spray dried plasma (SDP) on growth performance, carcass traits, tibia quality, and hemagglutination inhibition titers in broilers fed two nutritional strategies with high or low nutrient density. In the study, 816 one-day-old Ross 308 male broiler chickens were divided into a 2 × 2 factorial arrangements consisting of four treatment groups with 12 replicates (17 birds/replicate) based on diets with high nutrient density (HND) or low nutrient density (LND) from d 0 to 42 and receiving either control or 1% SDP diets during d 0 to 10. The results showed that feed intake (FI) and body weight gain (BWG) were increased (P < 0.05) and feed conversion ratio (FCR) was significantly reduced (P = 0.003) for broilers fed HND diets from d 0 to 42. The inclusion of SDP increased the BWG (P < 0.001), FI (P < 0.001), and FCR (P < 0.05) during d 0 to 10 of broiler life but not effect of SDP was observed for the whole 0-42 d period. Carcass yield increased with HND (P < 0.001) and dietary SDP (P = 0.002). However, HND feeding significantly decreased liver (P < 0.001), bursa of Fabricius (P = 0.002), abdominal fat (P < 0.001), proventriculus (P < 0.001) and gizzard weight (P < 0.001), but increased heart weight (P = 0.013), although spleen weight remained unaffected (P > 0.05) on d 42. Tibial bone morphometric and mechanical properties improved (P < 0.05) with SDP supplementation, and bone ash, Ca, and P remained unaffected (P > 0.05) on d 14. With the exception at d 28 (P = 0.037), the antibody titer to ND virus was similar among all treatment groups (P > 0.05) at d 0, 14, and 42. In conclusion, HND diets improve performance of broilers during the whole period and SDP supplementation during starter phase improve performance at this period, but also increased carcass yield, and tibial quality. Therefore, inclusion of SDP in the starter diet could be a beneficial nutritional strategy to improve the health and production of broilers provided feeding strategies using various nutrient densities.

PSV-15 Effects of Supplementation of Protease to Different Nutrient Density of Diets on Growth Performance, Nutrient Digestibility, Blood Profile, Gas Emission, Fecal Microflora in Growing-Finishing Pig

Abstract This study was conducted to investigate the effects of protease supplementation and different nutrient density of diets on growth performance, nutrient digestibility, blood profiles, gas emissions, and fecal microflora in growing-finishing pigs. Crossbred growing pigs (n = 180; [Landrace × Yorkshire] x Duroc) with an initial body weight (BW; 18.74 ± 3.46 kg) were used for 15 weeks. Pigs were randomly assigned to 6 dietary treatments with 6 replicates of 3 pigs per pen in a 3 ⅹ 2 factorial through the following arrangement: Three groups of protease (1, Basal diets; 2, Protease A: 125 mg/kg protease derived from Streptomyces spp; 3, Protease B: 100 mg/kg protease derived from Bacillus licheniformis) at two different nutrient density diets (1; Basal requirement 2; 0.94-0.98% greater than requirement in dietary protein and 50 kcal/kg in energy). Supplementation of protease significantly increased (P &amp;lt; 0.05) BW at weeks 4 and 6. Also, supplementation of protease increased (P &amp;lt; 0.05) ADG at grower periods and weeks 13 to 15. In addition, improvement (P &amp;lt; 0.05) of ADG was observed in pigs fed a high nutrient density diet (HN) compared with basal nutrient density diet (BN) at grower periods and weeks 13 to 15. In apparent total track digestibility (ATTD) of crude protein (CP), there was increased (P &amp;lt; 0.05) in supplementation of protease at weeks 6 and 13. The HN showed increased (P &amp;lt; .0001) ATTD of CP at 6 weeks. BN increased (P &amp;lt; 0.01) ATTD of CP at week 13. Also, there was interaction (P &amp;lt; 0.05) between nutrient density of diets and supplementation of protease. In ATTD of gross energy, supplementation of protease showed increased (P &amp;lt; 0.05) at week 13. The supplementation of protease in diets decreased (P &amp;lt; 0.05) the concentration of blood urea nitrogen (BUN) at week 13. The supplementation of protease in diets decreased (P &amp;lt; 0.05) the emission of NH3 at weeks 6 and 13. Also, H2S was decreased (P &amp;lt; 0.05) due to supplementation of Protease A in diets. At weeks 6 to 9, average daily feed intake showed a tendency to increase (P &amp;lt; 0.10) when the BN diets were fed. Also, during the entire period, feed conversion ratio tended to increase (P &amp;lt; 0.10) when the BN diets were fed. In conclusion, supplementation of protease reduces NH3 in feces and BUN in whole blood by increasing the digestibility of CP and improved growth performance. Also, diets with high nutrient density improved growth performance and nutrient digestibility in grower periods.

Ascites in Broiler: Updates

In recent years, intensive selection has resulted in the development of metabolic diseases, including ascites, in chickens as a consequence of their genetic potential to grow rapidly. Many factors interact to cause ascites, including management practices, environmental conditions, and genetic makeup. In the modern broiler industry, ascites syndrome (AS), also called pulmonary hypertension syndrome (PHS), is regarded as the main reason for morbidity and mortality. Current meat chicken lines have a faster metabolic process, which requires a greater amount of oxygen, particularly when they are fed high nutrient density diets or when they are kept in cold environments, Due to their underdeveloped cardiorespiratory systems, broilers cannot get enough oxygen to meet their requirements and suffer from hypoxemia, which in turn leads to pulmonary hypertension syndrome. A wide range of management practices as controlled feeding protocols, and limited lighting periods, besides adding antioxidants to feed, are outlined for reducing ascites incidence in broiler chickens. Also, the use of higher levels of dietary vitamins such as C and E, besides selenium, is believed to help lower the incidence of ascites. The improvement of low-temperature environmental shelter conditions appears to reduce the prevalence of PHS. Molecular genetics employed to diagnose and select against susceptible broilers' grandparents is being employed to eliminate involved genes.

Evaluation of Lactobacillus Plantarum Additive on Growth Performance, Excreta Microbiota, Nutrient Digestibility, Gas Emission, and Meat Quality in Ross308-Broilers

The intention of this study was to analyze the effects of Lactobacillus plantarum (L. plantarum) additive with different nutrient density diets on growth performance, excreta microbiota, nutrient digestibility, gas emission, and meat quality in Ross308-broilers. A total of 576 mixed-sex, 1-d old Ross-308 chicks were randomly allocated to one of four treatment groups with 8 replication and 18 chicks/cage. For a period of 35 days, HD and LD group chicks were fed with commercial corn and soybean meal-based basal diet which contains high and low nutrient density diet, respectively. The other treatment groups LP1 and LP2 chicks were fed with LD+ 0.05% and 0.01 % of L. plantarum, respectively. During day 21 and the overall experimental period, the body weight gain of broilers significantly increased (p<0.05) in HD and L. plantarum groups compared to the LD group. On day 35, broilers fed L. plantarum additive had significantly increased (p<0. 05) the nutrient digestibility of dry matter and nitrogen compared to those fed HD and LD diets. Moreover, dietary inclusion of L. plantarum additive had significantly increased (p<0.05) lactobacillus population and decreased (p>0.05) E. coli and ammonium emission. However, the meat quality traits were not affected by experimental diets. In conclusion, we infer that a low-density diet with 0.1% of L. plantarum additive could serve as an excellent alternative feed additive to enhance the performance of broilers.

Inclusion of probiotic (Lactobacillus plantarum) in high- and low-nutrient-density diets reveals a positive result on the growth performance, nutrient digestibility, gas emission, and blood profile in growing pigs

A total of 160 growing pigs (24.69 ± 1.89 kg) were randomly assigned to one of four treatments in a 2 × 2 factorial design with two different levels of nutrient density diet with or without 0.3% probiotic (Lactobacillus plantarum). Each treatment had eight replicates with five pigs (three gilts and two barrows) per pen. At the end of the trial, pigs fed 0.3% probiotic supplement had significantly increased body weight, whereas the average daily gain and gain to feed ratio was significantly increased in both probiotic and high-nutrient density (HD) diet. The nutrient digestibility of dry matter was significantly increased in pigs fed HD diet, whereas nitrogen and gross energy digestibility and blood characters immunoglobulin and lymphocyte counts were significantly increased in both HD and probiotic groups. Inclusion of HD diet with 0.3% probiotic significantly decreased NH3 and H2S gas emission. Moreover, nitrogen and energy showed a significant interaction between probiotic and density diet. In summary, dietary probiotics with HD diet increased the growth performance, nutrient digestibility, blood profile, and reduced gas emission. We suggest that 0.3% probiotic with HD diet could serve as an alternative feed additive to enhance the growth performance of growing pigs.

Effect of dietary fermented oats in different nutrient-density diets on growth performance, nutrient digestibility and ileal microorganisms of weanling pigs

A total of 160 crossbred weanling pigs [(Landrace × Yorkshire) × Duroc, 28 days old] with an initial bodyweight of 8.01 ± 0.74 kg were used in a 42-day trial (Phase 1: Days 1–14, Phase 2: Days 14–42). The experiment was conducted to evaluate the effects of the inclusion of fermented oats (FO) to a corn and soybean meal-based diet on the performance of weanling pigs fed with high nutrient-density (HD) and low nutrient-density (LD) diets. Pigs were randomly distributed into one of four dietary treatments in a 2 × 2 factorial arrangement. Two levels of nutrient density [LD = 3323 (Phase 1: 1–14 days) and 3269 kcal/kg (Phase 2: 14–42 days); HD = 3446 (Phase 1: 1–14 days) and 3325 kcal/kg (Phase 2: 14–42 days), the differences in dietary energy were based on differences in the content of fish meal, animal fat, corn and FO [0%, 5% (Phase 1) or 2.5% (Phase 2)] were used according to the bodyweight and sex of pigs [8 replicate pens per treatment with 5 pigs in a pen (3 gilts and 2 barrows)]. During the overall trial period (Days 1–42), the average daily gain and gain:feed ratio of pigs fed HD and FO diets were significantly higher (P ≤ 0.05) than those of pigs fed with LD and non-fermented oats diets respectively. On Day 14, the apparent total tract digestibility of dry matter and nitrogen of the HD groups were significantly greater (P ≤ 0.05) than those of the LD groups. The apparent total tract digestibility of energy of the FO groups was significantly greater (P ≤ 0.05) than that of the non-fermented oats diet groups during the whole experimental period. Pigs fed with FO showed higher (P ≤ 0.05) ileal Lactobacillus and lower (P ≤ 0.05) Escherichia coli counts compared with those fed with the non-fermented oats diet. In conclusion, administration of FO to a LD diet demonstrated beneficial effects on the growth performance, nutrient digestibility and ileal microorganisms balance of weanling pigs.

Guanidinoacetic acid supplementation in broiler chickens fed on corn-soybean diets affects performance in the finisher period and energy metabolites in breast muscle independent of diet nutrient density

ABSTRACT(1) Guanidinoacetic acid (GAA) is the single immediate endogenous precursor of creatine (Cr). It was hypothesised that dietary GAA would have different effects on performance and energy metabolites in breast muscle depending on the nutrient density (ND) of corn-soybean-based diets.(2) A total of 540 one-day-old male Ross 308 broilers were allocated to 9 dietary treatments with 6 replicates (10 birds each) in a 3 × 3 factorial arrangement with three levels of ND (low, 2800; medium, 2950 and high, 3100 kcal metabolizable energy (ME)/kg; and with the other nutrients being constant relative to ME) and supplemented with three levels of GAA (0, 0.6 and 1.2 g/kg) in a 42-d feeding trial.(3) In the starter and grower periods, increasing levels of ND improved body weight (BW), average daily gain (ADG), average daily feed intake (ADFI) and feed conversion ratio (FCR), with the exception of ADFI in the starter period. GAA supplementation did not affect performance characteristics. All performance indicators responded markedly to increasing ND in the finisher period, whereas the highest GAA level reduced ADFI compared to the unsupplemented control (156 vs. 162 g/d) and concomitantly FCR (1.81 vs. 1.93). No interactive effects were noted for any performance trait. The high ND diet resulted in more breast meat yield on d42, associated with higher fat content and darker colour compared to the other ND levels. The GAA supplementation did not affect carcass and breast traits. At the end of the experiment, Cr was elevated when feeding GAA at 1.2 g/kg (5455 vs. 4338 mg/kg fresh muscle).(4) To conclude, ND had a substantial effect on performance and carcass traits, whereas any effect of GAA was limited to FCR in the finisher period and independent of diet ND level.

A high nutrient dense diet alters hypothalamic gene expressions to influence energy intake in pigs born with low birth weight

The low birth weight (LBW) individual had greater risk of developing metabolic dysfunction in adulthood. The aim of this study was to test whether the LBW individual is more prone to glucose intolerance on a high nutrient dense (HND) diet, and to investigate the associated hypothalamic gene expressions using pigs as model. The intake of digestible energy intake, if calculated on a body weight basis, was greater in LBW pigs than that of normal birth weight (NBW) pigs. The LBW pigs fed the HND diet had greater digestible energy intake than those fed the NND diet at adulthood, which did not occur for NBW pigs. Notably, up-regulated hypothalamic toll-like receptor 4, interleukin 6 and phospho-NFκB p65 expressions, and the altered expressions of hypothalamic leptin receptor, suppressor of cytokine signaling 3, agouti-related protein and proopiomelanocortin predicted the overconsumption of energy intake and development of glucose intolerance in LBW pigs fed the HND diet. Collectively, pigs born with LBW had a distinct hypothalamic leptin signaling to a high nutrient dense diet, which contributed to greater energy intake and glucose intolerance.

Food security is related to adult type 2 diabetes control over time in a United States safety net primary care clinic population

Background/Objectives:Successful Type 2 diabetes management requires adopting a high nutrient-density diet made up of food items that both meet dietary needs and preferences and can be feasibly obtained on a regular basis. However, access to affordable, nutrient-dense foods often is lacking in poorer neighbourhoods. Therefore, low food security should directly impair glucose control, even when patients have full access to and utilize comprehensive medical management. The present study sought to determine whether food security is related longitudinally to glucose control, over-and-above ongoing medication management, among Type 2 diabetes patients receiving comprehensive care at a Midwestern multi-site federally qualified health centre (FQHC).Subjects/Methods:In this longitudinal observational study, we completed a baseline assessment of patients’ food security (using the US Household Food Security Module), demographics (via Census items), and diabetes history/management (using a structured clinical encounter form) when patients began receiving diabetes care at the health centre. We then recorded those patients’ A1C levels several times during a 24-month follow-up period. Three hundred and ninety-nine patients (56% with low food security) had a baseline A1c measurement; a subsample of 336 (median age=52 years; 56% female; 60% Hispanic, 27% African American, and 9% White) also had at least one follow-up A1c measurement.Results:Patients with lower (vs higher) food security were more likely to be on insulin and have higher A1c levels at baseline. Moreover, the disparity in glucose control by food security status persisted throughout the next 2 years.Conclusions:Although results were based on one multi-site FQHC, potentially limiting their generalizability, they seem to suggest that among Type 2 diabetes patients, low food security directly impairs glucose control—even when patients receive full access to comprehensive medical management—thereby increasing their long-term risks of high morbidity, early mortality, and high health-care utilization and cost.

Effect of early post-hatch nutrition on production performance of commercial broiler chicken

The study was conducted to access the effect of early post-hatch nutrition regimens on the productive performance of 384 number of commercial broiler chicken (Cobb 400). Different nutrient regimens include glucose and probiotic alone in hatcher tray and first day in pen and a high and very high density diet of 25 and 27 per cent dietary crude protein respectively and 3100 kcal ME/kg diet in hatcher tray and subsequent three days in pen along with glucose and probiotic alone in hatcher tray and first day in pen was provided. Later, all broiler chicks were switched over to the recommended commercial Cobb broiler diet up to 42 days. Body weight, feed efficiency and breast muscle fibre diameter were significantly higher in treatment groups. No significant difference existed between different treatment groups for hatchability, livability percent, carcass characteristics and cut up parts. Trimmable fat per cent was significantly higher (P less than 0.01) in control birds. It may be concluded that early post hatch nutrition with high nutrient dense diet resulted in better production performance in commercial broiler chicken.

Effects of Lactobacillus acidophilus supplementation in different energy and nutrient density diets on growth performance, nutrient digestibility, blood characteristics, fecal microbiota shedding, and fecal noxious gas emission in weaning pigs

This study was conducted to evaluate the effects of Lactobacillus acidophilus supplementation in different energy and nutrient density diets on growth performance, nutrient digestibility, blood characteristics (blood urea nitrogen and creatinine), fecal microbiota shedding, and fecal noxious gas emission in weaning pigs. A total of 140 crossed [(Landrace×Yorkshire)×Duroc] weaning pigs with an initial body weight (BW) of 7.51±0.79kg were used in a 42-day trial. Pigs were randomly allocated into one of four treatment groups in a 2×2 factorial arrangement with two levels of energy and nutrient density (Phase1: 3750 and 3900kcal/kg; Phase2: 3550 and 3700kcal/kg) and L. acidophilus (0 and 0.1%) according to sex and BW (7 replicates each with 2 gilts and 3 barrows). Pigs fed high energy and nutrient density diets increased (P<0.05) average daily gain (ADG), gain:feed (G:F) ratio, as well as H2S and acetic acid emission than those fed low energy and nutrient density diets. Pigs fed L. acidophilus supplementation diets increased ADG and G:F (P<0.05) compared with pigs fed diets without L. acidophilus supplementation. Moreover, L. acidophilus supplementation led to a significant (P<0.05) increase in DM digestibility on day 14 and shift microbiota by increasing fecal Lactobacillus, while decreasing E.coli counts, as well as a significant (P<0.05) decrease in serum BUN concentration and fecal noxious gas emission. The interactive effects (P<0.05) of dietary energy and nutrient density and L. acidophilus supplementation were observed on the fecal H2S and acetic acid gases emission. In conclusion, dietary supplementation of L. acidophilus improved growth performance, ATTD of DM, shifted microbiota by increasing fecal Lactobacillus and decreased E. coli counts, decreased BUN concentration and fecal noxious gas emission in weaning pigs. No interactive effects of L. acidophilus supplementation and dietary energy and nutrient density on growth performance, nutrient digestibility (DM, N, and GE), blood characteristics (BUN and creatinine) and microbiota (Lactobacillus and E. coli). While the beneficial effects of L. acidophilus supplementation on H2S and acetic acid gases emission are more dramatic with high energy and nutrient density diets.

Effect of feeding wheat- or barley-based diets with low or and high nutrient density on nutrient digestibility and growth performance in weaned pigs

Barley grain is commonly fed to growing-finishing pigs as the major cereal feed energy source in western Canada. However, its nutritional value for weaned pigs is poorly characterized. Formulating low nutrient dense diets may reduce feed cost. Weaned pigs may be able to maintain growth performance by adjusting feed intake to meet nutrient requirement. Four diets based on either 644g wheat/kg or 676g barley/kg with either 9.63 or 10.0MJ net energy (NE)/kg were fed to 208 weaned pigs (9.0kg) as a 2×2 factorial arrangement with 13 replicate pens per diet. Diets were formulated to have 1.07g standardised ileal digestible lysine/MJ NE and were fed for 21 days. Feed added, feed remaining and pig body weight were measured weekly to calculate pen average daily feed intake (ADFI), average daily gain (ADG) and feed efficiency (G:F). Faeces were collected to calculate diet apparent total tract digestibility (ATTD) of dry matter (DM), gross energy (GE) and crude protein (CP). Compared with wheat-based diets, feeding barley-based diets reduced (P<0.001) ATTD of DM, GE and CP by 2.7, 3.0 and 4.4%, respectively. Compared with high nutrient density (ND) diets, feeding low ND diets reduced (P<0.001) ATTD of DM, GE and CP by 2.6, 1.8 and 2.3%, respectively. For the entire trial (day 0–21), feeding barley increased (P<0.001) ADG by 41.2g/d and G:F by 0.04 compared with feeding wheat but did not affect ADFI (P>0.05). Diet ND did not affect (P>0.05) ADFI, ADG or G:F. In conclusion, feeding barley as cereal energy for weaned pigs instead of wheat grain may increase growth performance. Reducing dietary NE value by 0.37MJ/kg while maintaining the SID AA content/NE ratio did not affect growth performance in weaned pigs.

Influence of low or high density corn and soybean meal-based diets and protease supplementation on growth performance, apparent digestibility, blood characteristics and noxious gas emission of finishing pigs

This study was conducted to evaluate the influence of dietary supplementation of high and low nutrient density diets and protease on growth performance, apparent nutrient digestibility, blood metabolites, and excreta noxious gas emission in finishing pigs. A total of 140 pigs [(Landrace×Yorkshire)×Duroc] with an initial average body weight (BW) of 50.69±1.91kg were used in a 12-week trial. Pigs were blocked and stratified based on sex and body weight in a 2×2 factorial design with the following factors: 1) low or high nutrient density diet and 2) with or without Protease, 125g/t (Prot). Each treatment consisted of 7 replicate pens with 5 pigs (3 barrows and 2 gilts) per pen. Supplementation of protease significantly increased (P<0.05) ADG and G: F ratio during week 6 to12 and the G: F ratio was also significantly increased (P<0.05) overall. Trends in increased (P=0.08, 0.09 and 0.08) ADG was observed in pigs fed high density diet compared with low density diet during weeks 0–6, 6 to12 and overall respectively. Likewise, feed efficiency was significantly increased (P<0.05) in pigs fed high density diets compared with low density diets. A trend in interactive effect between diets and protease was observed for feed efficiency during wk 6–12. The co-efficient of apparent digestibility (CATTD) of DM, N and Energy was significantly higher (P<0.05) in pigs fed protease supplemented diet during wk 12. Nitrogen digestibility tended to increase (P=0.06) in high density diet than low density diet during wk 6. The supplementation of protease in the diet led to significantly higher (P<0.05) level of creatinine during wk 6 and lower (P<0.05) levels of cortisol and epinephrine in blood serum during wk 12. The concentration of creatinine tended (P=0.08) to be higher in high than low density diets during wk 12. The noxious gases were not affected (P>0.05) by density diets and protease. No interactions were observed between the diets and protease for nutrient digestibility, blood profiles and noxious gases emission.In conclusion, dietary supplementation with 125g/t of protease has beneficial effects on growth performance and CATTD. The stress related hormones were also reduced in pigs fed protease supplemented diets. In addition to tendency in weight gain, feed efficiency was improved in pigs fed high density diets than low density diets.

Inclusion of phytogenic blends in different nutrient density diets of meat-type ducks

A total of 160 1-day-old ducklings (average initial body weight of 53 g), were used in a 42-d feeding trial to evaluate the effects of reducing nutrient density of diets, and supplementing the diets with a phytogenic blend (quillaja, anise, and thyme) on their growth, carcass quality, and nutrient digestibility. After checking body weight on d 1, the birds were sorted into pens with 5 birds/pen and 8 pens/treatment. The treatments were: T1, Basal diet; T2, T1 + 150 ppm phytogenic blend; T3, T1 – (1% CP, 0.04% Lys, 0.05% Met+Cys, 0.02% Ca, and 0.02% P, and 50 kcal ME); T4, T3 + 150 ppm phytogenic blend. The results indicated that reducing nutrient density of the diets had an adverse effect (P < 0.05) on body weight gain (BWG) on d 1 to 21, d 21 to 42, and the overall experimental period. Supplementing the diets with the phytogenic blend improved (P < 0.05) BWG and feed conversion ratio (FCR) on d 21 to 42 and the overall experimental period. Feed intake was not affected by treatments. Low nutrient density diets increased (P < 0.05) the cooking loss percentage of breast meat. Supplementing the diets with the phytogenic blend decreased (P < 0.05) the lightness of breast meat. The percentage of drip loss was influenced (P < 0.05) by nutrient density and the phytogenic blend on d 1 and d 7. The relative weights of breast meat, abdominal fat, gizzard, liver, spleen, and bursa of Fabricius, pH, and TBARS values were not affected by the treatments. The digestibility of dry matter, energy, nitrogen, ADF, and NDF was decreased (P < 0.05) by reducing nutrients density of the diets, but addition of the phytogenic blend alleviated (P < 0.05) the negative effects of lowering the nutrient density. The results indicated that the ducks fed high nutrient density diets supplemented with the phytogenic blend showed higher BWG and nutrient digestibility and lower FCR, cooking loss, drip loss, and TBARS value, without any negative effect on meat quality and relative organs weights.

EFFECTS OF FEEDING HIGH-NUTRIENT-DENSITY DIETS ON PERFORMANCE OF BOVANS WHITE HENS REARED UNDER SUMMER CONDITIONS IN EGYPT

The present study was undertaken to determine the effects of feeding diets containing high nutrient concentrations on laying performance and egg quality of Bovans White laying hens during the summer season in Egypt. Two hundred hens were randomly distributed into five equal experimental groups, each composed of five replications. Hens were maintained at community cages (8 birds/cage) and subjected to similar hygienic and managerial conditions.A corn-soybean meal-based diet, containing 17.40% crude protein, 2880 kcal/kg of metabolizable energy, 4.35% calcium, 0.43% nonphytate phosphorus, 0.84% lysine, 0.41% methionine, and 0.70% methionine plus cysteine, was formulated in mash form and used as a control. The concentration of nutrients was increased to be 102.5, 105, 107.5 and 110% of those present in the control diet through some dietary manipulations, thus five mash experimental diets were formulated and fed to hens. The laying performance was evaluated in terms of egg production rate, egg weight, daily egg mass, daily feed intake and feed conversion ratio during three 28-day periods, from 44 to 56 weeks of age. An egg quality test was also performed to determine the effects of feeding the high-nutrient-density diets on egg components and some exterior and interior parameters of egg quality at the last week of study. At the first 4-week period, feeding the high-nutrient-density diets had no significant effect on laying performance of hens but daily feed intake was inconsistently affected.At the second period, hens fed high-nutrient-density diets achieved significantly higher egg production rate (EPR) and daily egg mass (DEM) compared with the control group while egg weight (EW), daily feed intake and feed conversion ratio (FCR) were not affected. At the third period, hens fed 105 and 107.5% diets consumed significantly more feed and displayed higher EPR and DEM than those of other dietary treatments but EW and FCR were not affected. Feeding the high nutrient density diets produced significant improvements in egg weight, yolk index and Haugh units compared with their control counterparts while percentages of egg components, shell weight per unit surface area (SWUSA), egg shape index and yolk color score were not affected. It is concluded that increasing dietary nutrient density up to 110% of the recommended requirements of Bovans White laying hens can positively affect some egg quality traits but had inconsistent effect on their productive performance under Egyptian summer conditions.

Influence of protected organic acid blends and diets with different nutrient densities on growth performance, nutrient digestibility and faecal noxious gas emission in growing pigs

This study was conducted to evaluate the effects of dietary supplementation of protected organic acid blends including medium chain fatty acids and different nutrient density diets on growth performance, nutrient digestibility and faecal noxious gas content in growing pigs. A total of 80 crossed [(Landrace &amp;times; Yorkshire) &amp;times; Duroc] growing pigs with an initial body weight (BW) of 22.61 &amp;plusmn; 2.32 kg were used in a six-week trial. Pigs were randomly allocated into one of four treatment groups in a 2 &amp;times; 2 factorial arrangement with two levels of nutrient density (high and low) and protected organic acid (0% and 0.1%) according to their sex and BW (five replicates with two gilts and two barrows per pen). Pigs fed high nutrient density diets had increased (P &amp;lt; 0.05) average daily gain (ADG0 and gain: feed (G : F) than those fed low nutrient density diets. Likewise, pigs fed protected organic acid diets exhibited increased (P &amp;lt; 0.05) ADG compared with pigs fed no additional protected organic acids. An interactive effect (P = 0.03) between organic acid and nutrient density was observed on feed conversion by pigs. Dry matter (DM) digestibility tended to improve (P = 0.08) in pigs fed high nutrient density diets compared with low nutrient density diets. However, nitrogen (N) and energy (E) digestibility was not influenced by the nutrient density. Likewise, protected organic acid supplementation did not influence (P &amp;gt; 0.05) DM, N or E digestibility. Organic acid supplementation reduced (P &amp;lt; 0.05) H&lt;sub&gt;2&lt;/sub&gt;S content from faeces on Day 1, Day 3, Day 5 and Day 7 of incubation. Low nutrient density diets led to a reduction (P &amp;lt; 0.05) in H&lt;sub&gt;2&lt;/sub&gt;S gas content on Day 1 of incubation. No interactive effect on faecal noxious gas content was observed between nutrient density and organic acid. In conclusion, dietary supplementation of protected organic acids with a high nutrient diet improved growth performance and reduced H&lt;sub&gt;2&lt;/sub&gt;S acid emission. &amp;nbsp;

Changes of haematic parameters, redox status and mitochondrial complex activity in the heart and liver of broilers fed with different density diets under low ambient temperature

This experiment was conducted to investigate the influence of dietary nutrient density on haematic parameters, oxidative status and mitochondrial complex activity in the heart and liver of broilers under low ambient temperature. Eight-day-old male ROSS-308 chickens were randomly divided into two treatments fed with normal (control) and high metabolizable energy (ME) and crude protein density (H) diets. A high nutrient density diet increased body weight gain and reduced the feed conversation ratio during the first 3 weeks. Increased ascites-related mortality (weeks 4 to 6), right ventricle/total ventricle (week 6), blood haemoglobin (weeks 2 and 4) and mean corpuscular haemoglobin (week 2) were observed in treatment H. Levels of malonaldehyde and protein carbonylation were increased at week 4, and activities of glutathione peroxidase at week 4 and CuZn superoxide dismutase and catalase at week 6 were decreased in the heart; only malonaldehyde (week 6) was increased in the liver in treatment H. Relative mRNA expression of hypoxia inducible factor-1 (heart) was increased and heme oxygenase-1 (heart and liver) was decreased at week 4 in broilers fed with high ME and protein diet. Activities of mitochondrial complex III and IV (week 6) in the heart, and complex I (week 6) and complex III and IV (week 4) in the liver were decreased in treatment H. In conclusion, high levels of dietary ME and protein resulted in oxidative stress and high incidence of ascites in broilers under low ambient temperature. Heart dysfunction was primarily attributed to ascites development, in which oxidative injury and inhibition of mitochondrial complex activity were involved.

Effect of dietary nutrient density and vitamin premix withdrawal on performance and meat quality of broiler chickens

The objective of this study was to evaluate the effects of feeding high- and low nutrient density diets, and three different vitamin premix withdrawal regimes on broiler performance and meat quality. Male broiler chicks (480 days old) were reared on the floor in a 2 × 3 factorial arrangement for 42 days. Chickens were slaughtered at 42 days of age and meat samples kept at -20 ± 1°C and analysed after 1, 90 and 180 days of storage. Broiler performance was significantly affected by dietary nutrient density. Vitamin premix withdrawal had no significant effect on body weight. The results showed no significant differences between nutrient density and vitamin premix withdrawal on lightness (L*), redness (a*) and yellowness (b*). Oxidative stability of thigh muscle lipids during frozen storage was significantly affected by nutrient density, while vitamin premix withdrawal had no significant impact on lipid oxidation. High nutrient density diet led to a significantly (P < 0.05) decreased pH compared with the low nutrient density diet. Increasing dietary nutrient density improved broiler performance but impaired meat quality while vitamin premix withdrawal during finisher periods had no negative effect on broiler performance and meat quality.

Effect of probiotics supplementation in diets with different nutrient densities on growth performance, nutrient digestibility, blood characteristics, faecal microbial population and faecal noxious gas content in growing pigs

A total of 144 pigs with initial BW of 29.48±0.58 kg were used in a 6-wk experiment to evaluate the probiotics supplementation (Enterococcis faecium, 1.0×1010 CFU/g) with different nutrient densities in growing pigs. Pigs were randomly allotted to one of four treatments in a 2×2 factorial arrangement of treatments with two levels of nutrient density and probiotic (0 or 0.1%) according to their sex and BW (nine replicate pens with two gilts and two barrows per pen). Pigs fed the higher nutrient density diets led to a higher (P<0.05) ADG and G:F ratio than those fed low nutrient density diet. The inclusion of probiotic increased (P<0.05) ADG, ADFI, G:F, and the apparent total tract digestibility of DM, N, energy. Dietary high nutrient density led to a higher (P<0.05) faecal H2S and NH3 content, whereas the probiotic supplementation led to a reduced (P<0.05) faecal H2S and NH3 content. An increased faecal lactobacillus concentration was observed with probiotic supplementation. An interactive effect between energy and nutrient density diet and probiotic was observed on the ADG and G:F ratio, faecal lactobacillus, apparent total tract digestibility and faecal noxious gas content. In conclusion, both dietary probiotic supplementation and a high nutrient diet could improve growth performance and nutrient digestibility in growing pigs. The beneficial effect of probiotic supplementation in pigs could be enhanced with the high energy and nutrient density diets.

Phase feeding in a big-bird production scenario: Effect on growth performance, yield, and fillet dimension

Phase feeding (PF) has been effective at maintaining broiler growth while reducing production cost, but the effect on different broiler strains and sex has not been assessed. An experiment was conducted using 4 commercial broiler strains grown up to 63 d of age (n = 1,440), comparing a PF approach to an industry-type diet. At d 17, birds began either the industry or PF regimen. The industry regimen consisted of average industry nutrient levels with periods from 17 to 32 d, 32 to 40 d, 40 to 49 d, and 49 d to the end of trial. For PF, diets were prepared that contained Lys, sulfur amino acids, and Thr levels matching the predicted requirements for birds at the beginning (high nutrient density) and end (low nutrient density) of PF. Pelleted high and low nutrient density diets were blended to produce rations containing amino acid levels that matched the predicted PF requirements over 2-d intervals. Weight gain, feed intake, and feed efficiency were calculated through d 58. Birds were commercially processed at 59, 61, or 63 d; yield and fillet dimensions were measured. Phase feeding did not effect weight gain or feed intake of broilers during the overall growth period (17-58 d). For most strains, PF did not effect final BW, yield, or fillet dimensions. However, strain and sex had greater effects on growth performance, yields, and fillet dimensions. Strains B and D had greater breast yield than strains A and C. Reduced feed costs ($0.01 to $0.04 per kilogram of gain, depending on strain) were observed for all strains with PF for the overall growth period (17-58 d). Therefore, potential savings on feed costs are possible for all strains used in this study with the incorporation of the PF regimen.