Growth performance of Hubbard × Cobb 500 and Ross × Ross 708 male broilers fed diets varying in apparent metabolizable energy from 14 to 28 days of age

The cost of energy-contributing ingredients has increased over the last several years. Defining minimum dietary energy specifications for broilers is a strategy to mitigate high diet cost. Two experiments were conducted to evaluate the effects of diets with graded concentrations of AME_n fed to Hubbard × Cobb 500 (experiment 1) and Ross × Ross 708 (experiment 2) male broiler chicks from 14 to 28 d of age. Both experiments were identical in experimental procedures with the exception of genetic strain. Broilers were fed a common corn-soybean meal-based starter diet from 1 to 13 d of age. At 14 d of age, dietary treatments were provided with 1 of 6 concentrations of AME_n (3,000, 3,030, 3,060, 3,090, 3,120, and 3,150 kcal/kg). In experiment 1, BW gain, feed intake, and FCR of Hubbard × Cobb 500 broilers decreased linearly with increasing AME_n. Linear broken-line response of FCR was estimated at 3,062 kcal of AME_n/kg based on broken-line methodology. In experiment 2, Ross × Ross 708 broilers did not respond to graded concentrations of energy, as indicated by linear and quadratic regression of BW gain, feed intake, caloric conversion, and FCR data. Therefore, Hubbard × Cobb 500 male broilers respond to AME_n from 14 to 28 d of age and may be fed diets formulated at 3,062 kcal of AME_n/kg without loss of performance. Conversely, growth performance of Ross × Ross 708 male broilers was not affected by varying AME_n (3,000 to 3,150 kcal/kg) from 14 to 28 d of age. In addition, the response to AME_n may not be as pronounced with the modern broiler compared with broilers used in previous research.     

Evaluation of a high-protein DDGS product in broiler chickens: performance,nitrogen-corrected apparent metabolisable energy,and standardised ileal amino acid digestibility

ABSTRACT

1. New production processes and additional uses for corn co-products have increased the availability of distiller’s dried grains with solubles (DDGS) with varying energy and amino acid digestibility, for use in poultry feed. The objective of this study was to determine the performance, N-corrected metabolisable energy (AME_n), and amino acid (AA) digestibility of a 34% CP (as fed) high-protein DDGS (HP-DDGS) included in poultry diets for Cobb 500 broiler chickens.

2. A total of 832 Cobb 500 broilers were randomly assigned to four dietary treatments containing 5% conventional DDGS (CV-DDGS) as a control or 10%, 15% and 20% HP-DDGS and fed for 42 d. After the performance trial, 240 birds from the original 832 were selected for a concurrent AME_n and AA digestibility experiment consisting of two AME_n diets and two AA diets.

3. Birds fed diets containing 15% and 20% HP DDGS gained less weight than birds fed the CV-DDGS (P < 0.05) but did not differ in feed intake (FI), and therefore had a less efficient FCR than the control (P < 0.05). The AME_n of HP-DDGS was determined to be 11.4 MJ/kg. The standardised ileal amino acid digestibility (SIAAD) of the essential amino acids Lys and Met were determined to be 80.9% and 88.6%, respectively.

4. HP-DDGS can be included in broiler diets up to 10% without any negative impact on performance or requiring supplemental Lys and Arg. The results from the AA digestibility study indicated that HP-DDGS could be a good source of digestible Lys.     

Nutrient Composition and Digestibility of Organic Broiler Diets and Pasture Forages

Poultry diets are formulated based on requirements of birds reared without access to pasture. Consumer demand for organic and free-range poultry has resulted in an increase in the use of certified organic feed. Organic poultry may have the opportunity to utilize nutrients found in forage. The addition of exogenous enzymes and manipulation of cecal microbial populations may affect the utilization of forage nutrients. The objectives of this study were as follows: 1) to determine AME_n and TME_n of organic grower diets with or without nonstarch polysaccharide enzyme supplementation and compare these values to a conventional grower diet, 2) to determine AME_n, TME_n, and true amino acid digestibility (TAAD) of forage samples with or without nonstarch polysaccharide enzyme supplementation, and 3) to determine if cecum modification affects forage AME_n, TME_n, and TAAD. The experiment was conducted using cecectomized, intact, and intact grass-fed roosters as models. Enzyme supplementation increased AME_n and TME_n values for organic feeds but not forage. Bird type had no effect on AME_n and TME_n for any treatment. The TAAD of forage was not significantly affected by enzyme supplementation. However, trends in bird type effect were observed for several amino acids.     

The effect of dietary fish oil soapstock on the performance,carcass fat and flavour of broilers 1

Three hundred and thirty six male broilers were fed on diets containing two levels (2% and 4%) of either acidulated soybean oil soapstock (SOS), acidulated fish oil soapstock (FOS), or a combination of the two. Some of the replicates were changed from FOS diets to diets containing 4% SOS at 5 or 6 1/2 weeks of age.

Dietary FOS was slightly, but significantly, inferior to SOS with regard to live performance, apparently due to an adverse effect on food intake. All birds fed on FOS were unpalatable due to a pronounced “fishy” flavour, thigh meat being more objectionable than breast meat and cooked broth more than roasted meat. About 3 to 4 weeks after transfer to SOS diets, the broilers were acceptable.

Both soapstocks contained over 65% free fatty acids, but their fatty acid composition differed, with the FOS containing more C₁₂ to C₁₆ saturated fatty acids, palmitoleic acid and the typical long‐chain polyenoic fatty acids, but much less linoleic acid. These patterns were reflected in the total dietary lipids and in the abdominal adipose tissue. After the type of dietary soapstock was altered, there was a gradual change in the composition of body fat, which, after about 3 weeks, approached the fatty acid pattern of the birds fed on a diet containing 4% SOS throughout their growing period.     

Effects of xylanase supplementation of corn-soybean meal-dried distiller's grain diets on performance,metabolizable energy,and body composition when fed to first-cycle laying hens

The increased cost of energy for laying hen diets has resulted in the use of enzymes, such as xylanase, to increase energy digestibility and thereby reduce the need for dietary energy. A 24-wk-long experiment was conducted using 432 twenty-week-old Hy-Line W36 first-cycle laying hens to determine the effects of energy concentrations and xylanase supplementation (Hostazym X 100) on hen performance, ME, and body composition. Three concentrations of dietary energy were fed with and without xylanase supplementation in a 3 × 2 factorial arrangement of treatments. Diets were reformulated twice over the experiment (wk 30 and 40) due to increased feed intake or changes in egg production. Dietary energy main effect treatments included a control (C), C − 77 kcal/kg, and C − 154 kcal/kg diets. Egg production, feed intake, BW, egg weight, egg mass, and FE data were collected during the experiment. Nitrogen-corrected AME was determined at 32 and 44 wk of age, and featherless body composition (crude fat, CP, and ash) was determined at 44 wk of age. Hen-day egg production was increased in hens fed dietary xylanase during wk 31 to 40 and 20 to 44. Feed intake was increased with reduced dietary energy during all periods evaluated. Egg mass and FE were improved with xylanase supplementation during wk 31 to 40 and 20 to 44. Hen BW was not different among treatments and egg weight was only significantly different at select time periods with no consistent responses over time. Main effects at hen wk 32 showed that reduced energy resulted in reduced AME_n and xylanase increased AME_n. In contrast, xylanase treatment resulted in reduced AME_n when measured at the end of wk 44. Overall, supplementation of xylanse to laying hens increased egg production, egg mass, and FE, although AME_n results were inconsistent and body composition data were dependent on dietary energy.     

Fatty acid composition of intramuscular fat from Nellore steers fed dry or high moisture corn and calcium salts of fatty acids

The purpose of this work was to evaluate the fatty acid composition of the Longissimus muscle from carcasses of Nellore steers fed diets with calcium salts of fatty acids (CSFA) and high moisture corn. Forty eight steers were fed during 70 days four diets containing dry corn (DC), high moisture corn (HM), dry corn plus CSFA (DC-CSFA) or high moisture corn plus CSFA (HM-CSFA). Fatty acid composition of the Longissimus muscle was determined by gas chromatography. Corn type had no effect on the ether extract percentage and in the content of the majority of the fatty acids, although steers fed HMC showed higher levels of polyunsaturated fatty acids and polyunsaturated/saturated ratio. Feeding CSFA increased ether extract percentage but had no effect on total of saturated, unsaturated and saturated: unsaturated ratio. Both high moisture corn and calcium salts of fatty acids increased CLA (cis9, trans11) and total CLA concentrations in intramuscular fat.     

L-肉碱对肉鸡脂质代谢的影响

160只1日龄艾维茵肉仔鸡随机分为4组,每组40只,分别饲喂添加0、30、50和100m gk/gL-肉碱的玉米-豆粕型日粮,以研究L-肉碱对肉鸡脂质代谢的影响。经7周试验,结果表明:L-肉碱显著影响了肉鸡血清中甘油三酯、胆固醇、游离脂肪酸、高密度脂蛋白胆固醇的含量和肉鸡腹脂率(P<0.05或0.01),但对肉鸡的生长性能未产生显著影响P(>0.05)。综合各项指标的变化,似100mg k/g L-肉碱对肉鸡的脂肪和胆固醇代谢有较明显的影响。     

Effect of high-oil corn or added corn oil on ruminal biohydrogenation of fatty acids and conjugated linoleic acid formation in beef steers fed finishing diets

Three Angus steers (410 kg) cannulated in the proximal duodenum were used in a replicated 3 x 3 Latin square to evaluate the effects of dietary lipid level and oil source on ruminal biohydrogenation and conjugated linoleic acid (CLA) outflow. Dietary treatments included: 1) typical corn (TC; 79.2% typical corn), 2) high-oil corn (HOC; 79.2% high-oil corn), and 3) the TC diet with corn oil added to supply an amount of lipid equal to the HOC diet (OIL; 76.9% TC + 2.4% corn oil). Duodenal samples were collected for 4 d following 10-d diet adaptation periods. Data were analyzed with animal, square, period, and treatment in the model and planned, nonorthogonal contrasts were used to test the effects of dietary lipid content (TC vs HOC and OIL) and oil source (HOC vs OIL) on ruminal biohydrogenation. Intake and duodenal flow of total long-chain fatty acids were increased (P < 0.05) by over 63% for diets containing more lipid regardless of oil source. Apparent ruminal dry matter and long chain fatty acid digestibilities were not altered (P > 0.05) by dietary lipid level or oil source. Ruminal biohydrogenation of total and individual 18-carbon unsaturated fatty acids was greater (P < 0.05) for diets with higher lipid content. Biohydrogenation of oleic acid was greater (P < 0.05) for HOC than OIL, but biohydrogenation of linoleic acid was lower (P < 0.05) for HOC than OIL. Duodenal flows of palmitic, stearic, oleic, linoleic, and arachidic acids were more than 30% greater (P < 0.05) for diets containing more lipid. Flow of all trans-octadecenoic acids was greater (P < 0.05) for diets containing more lipid. Corn oil addition increased (P < 0.05) the flow of trans-10 octadecenoic acid and the trans-10, cis-12 isomer of CLA by threefold compared to feeding high-oil corn. Feeding high-oil corn or adding corn oil to typical corn rations increased intake, biohydrogenation, and duodenal flow of unsaturated long-chain fatty acids. Compared with high-oil corn diets, addition of corn oil increased duodenal flow of trans-10, trans-12 and cis-12 isomers of octadecenoic acid and the trans-10, cis-12 isomer of CLA. The amount of cis-9, trans-11 isomer of conjugated linoleic acid flowing to the duodenum was less than 260 mg/d, a value over 20 times lower than flow of trans-11 vaccenic acid indicating the importance of tissue desaturation for enhanced conjugated linoleic acid content of beef.     

Influence of high dose of phytase and an emulsifier on performance,apparent metabolisable energy and nitrogen retention in broilers fed on diets containing soy oil or tallow

1. The effects of high dose of microbial phytase and an emulsifier on the performance, apparent metabolisable energy (AME) and nitrogen (N) retention in broilers fed on diets containing different fat sources were examined in a 5-week trial. Two fat sources (soy oil and tallow), two inclusion levels of E. coli phytase (500 or 1000 phytase units (FTU)/kg diet) and two inclusion levels of lysolecithin emulsifier (0 or 3.5 g/kg of diet) were evaluated in a 2 × 2 × 2 factorial arrangement of treatments.

2. Throughout the 5-week trial, soy oil supplementation improved weight gain and feed per gain compared with tallow, but had no effect on feed intake.

3. The high dose of phytase increased the weight gain and feed intake and lowered the feed per gain during d 1–21, but had no effect on performance parameters over the whole trial period.

4. An effect of emulsifier was observed for feed intake during d 1–21 and over the whole trial period. Addition of emulsifier increased feed intake compared with diets without emulsifier.

5. During weeks 1, 2, 3 and 5, birds fed on soy oil–based diets had higher nitrogen-corrected AME (AME_N) compared with those fed on tallow-based diets. During weeks 2, 3 and 5, the effect of phytase was significant for AME_N, with the high dose increasing the AME_N. During week 2, AME_N was increased with emulsifier addition.

6. During weeks 1, 2, 3 and 5, birds fed on soy oil–based diets had higher fat retention compared with those fed on tallow-based diets. The high dose of phytase improved the retention of fat during week 5 and the addition of emulsifier resulted in higher fat retention during week 1.

7. During weeks 2, 3 and 5, an interaction between fat source × phytase × emulsifier was observed for N retention. In soy oil–based diets, emulsifier plus 1000 FTU/kg phytase increased N retention compared with other groups, while in tallow-based diets, emulsifier addition increased N retention in diets with 500 FTU/kg, but not in 1000 FTU/kg diet.

8. Overall, the present data suggest that the dietary fat source influenced performance, AME_N and fat retention in broiler chickens. There is opportunity to improve bird performance during d 1–21, AME_N and fat retention with higher doses of microbial phytase. Addition of the emulsifier increased the AME_N during week 2 and tract retention of fat during week 1, but this effect was not translated into improvements in performance.

     

Chronic effects of moniliformin in broiler and turkeys fed dietary treatments to market age

Floor pen studies were conducted, with broilers from 1 to 7 wk of age and with turkeys from 1 to 14 wk of age, to evaluate the chronic effects of moniliformin (M). Fusarium fujikuroi (M-1214) culture material was added to typical corn-soybean basal diets to supply 0, 25, or 50 mg M/kg diet (broilers) or 0, 12.5, 25, 37.5, or 50 mg M/kg diet (turkeys). Compared with controls, chicks fed diets containing 50 mg M/kg consumed more feed, had lower body weight gain, were less efficient in converting feed to body weight gain, and had increased relative heart and proventriculus weights. Chicks fed the diet containing 50 mg M/kg also had significantly higher mortality and decreased mean corpuscular volumes compared with controls. Broilers fed 25 and 50 mg M/kg also had increased serum gamma glutamyltransferase activities. Feed intake, body weight gain, and feed conversion of turkeys fed dietary M were not affected. At 6 and 14 wk, turkeys fed 25, 37.5, or 50 mg M/kg diet had increased (P < 0.05) relative heart weights when compared with controls. At week 14, turkeys fed diets containing 37.5 or 50 mg M/kg also had increased (P < 0.05) relative liver weights compared with turkeys fed 0, 12.5, or 25 mg M/kg diet. Lesions, observed only in the hearts of broilers and turkeys fed 50 mg M/kg, were loss of cardiomyocyte cross striations, increased cardiomyocyte nuclear size, and an increased number of cardiomyocyte mitotic figures (turkeys only). Results indicate that > or = 37.5 mg M/kg is hepatoxic and > or = 25 mg M/kg is cardiotoxic to turkeys and 50 mg M/kg diet is toxic to broilers fed to market age.     

A comparison of methods for estimating the metabolisable energy of a sample of grass meal

1. The inclusion of grass meal in the diets of broilers and laying hens reduced food intake and, as a consequence, the apparent metabolisable energy (AME) and nitrogen‐corrected AME (AME_N) values estimated for the grass meal were artificially low.

2. With young broilers the AME and AME_N values of a sample of grass meal were estimated to be 5.97 ± 0.45 and 6.05 + 0.46 MJ/kg dry matter respectively.

3. With adult laying hens the AME and AME_N values of the sample of grass meal were estimated to be 5.36 ± 1.04 and 6.26 ± 0.96 MJ/kg dry matter respectively and the corresponding true metabolisable energy (TME) and nitrogen‐corrected TME (TME_N) values were shown to be 9.12 ± 1.25 and 8.66 ± 1.33 MJ/kg dry matter.

4. It was further illustrated that if the dietary intake of the adult birds had been 100 g/d, the AME value of the grass meal would have been estimated as 8.33 MJ/kg dry matter.     

Effects of sex,age and food intake upon metabolisable energy values in broiler chickens

1. Nitrogen‐corrected apparent metabolisable energy (AME_n) values of 2 diets with different energy: protein ratio were estimated in an experiment with 8 groups of female and 8 of male chickens in 15 sequential 3‐day balance periods from the 12th to the 56th d of age.

2. The effect of sex on AME_n values was not significant.

3. The effect of age was highly significant. AME_n values of the mixture with the narrower energy: protein ratio increased with age. The dependence of AME_n of the diet with the wider energy: protein ratio on age was parabolic, AME_n values increasing only until the 37th day of life.

4. Under conditions of ad libitum feeding, AME_n of the mixture with the wider energy: protein ratio given to female chickens decreased significantly with increasing food intake.     

Performance of Commercial Laying Hens When Fed Diets with Various Sources of Energy

Two experiments were conducted to determine the influence of adding various fat sources to the diet of the aged (76 to 84 wk) commercial laying hen. In experiment 1, corn-soybean meal diets were fed with 0, 2 and 4% corn oil. A diet containing 13.85% wheat bran was fed with and without 4% corn oil. A sixth diet contained 2% corn oil and 26.21% sugar. No difference in egg production among the 6 treatments was observed. The addition of 4% corn oil produced a nonsignificant increase in egg weight. The corn-soybean meal diet containing no corn oil also was used as the control in experiment 2. Seven treatment diets were fed with 4% fat from various sources. No difference in egg production among the 8 treatments was observed. Egg weight was higher when the diet contained added fat except when tallow was added.     

Fatty acid composition,fat deposition,lipogenic gene expression and performance of broiler fed diet supplemented with different sources of oil

The present study assessed the effect of feeding palm oil (PO), sunflower oil (SO) and their combination on performance, fat deposition, fatty acid composition and lipogenic gene expression of broilers reared for 42 days. A total of 144 1‐day‐old broilers (Cobb500) were randomly allotted into four treatment diets with each having six replicates of six chicks in each replicate following a completely randomized design. Live weight gain and feed efficiency was significantly (P < 0.05) higher in birds fed with a combination of oil sources compared to controls. Birds fed with the combination of oil and SO alone had higher carcass yield and lower abdominal fat. Higher (P < 0.05) concentrations of unsaturated fatty acids (UFA) and lower concentrations of palmitic acid and saturated fatty acid (SFA) was found in birds fed SO alone and combinations of SO and PO. Furthermore, the outcomes showed that birds fed diet supplemented with SO and the combination of SO and PO down‐regulated gene expression of key hepatic lipogenic enzymes of fatty acids synthase (FAS), acetyl‐CoA carboxylase (ACC) and stearoyl‐CoA desaturase (SCD). These findings suggest that the diet containing the combination of 2% PO and 4% SO may reduce hepatic lipogenesis, as well as lower abdominal fat content of broilers.     

Effects of dietary distillers dried grains with solubles (DDGS) on growth performance,oxidative stress,and immune function in broiler chickens

Distillers dried grains with solubles (DDGS) from corn contain relatively large amounts of polyunsaturated fatty acids and some yeast components, which may increase oxidative stress and alter immune function, respectively, when fed to broilers. Therefore, the study was undertaken to assess the effects of distillers dried grains with soluble (DDGS) on broilers under immunosuppressive challenge. One-day-old male broiler chickens (300) were assigned to 2 treatments with 6 replicates pretreatment. Birds were fed diets formulated to contain 0, 15% corn-based DDGS, respectively. The experimental diets were fed for 6 weeks in 2 phases. On day 21, serum IgA, IgG content and malondialdehyde (MDA), glutathione peroxidase (GSH-Px), total superoxide dismutase (T-SOD), and total antioxidant activity (T-AOC) capacity were analyzed. Chickens were then randomly allotted to 1 of 4 treatment groups: negative control (NC) corn-soybean meal diet without dexamethasone (DEX) challenge, positive control (PC) corn-soybean meal diet with (DEX) challenge, 15% DDGS without DEX challenge (D), 15% DDGS with DEX (D+DEX). Based on these results, dietary DDGS did not influence ADG, ADFI and F:G of 21 d, 28 d and 42 d chicks (P > 0.05), however, DEX affected ADG and F:G of 28 d chicks remarkably (P < 0.05). Relative weights of liver, abdominal fat, spleen, thymus, and bursa were influenced by DEX challenge on d 28 (P < 0.05). DDGS reduced serum T-AOC, T-SOD, whereas increased IgA, IgG and MDA of 21-day-old broilers significantly (P < 0.05). Dietary DDGS also reduced liver T-SOD of 21-day-old broilers significantly (P < 0.05). Based on real-time PCR, 28 d chicks fed DDGS had a greater relative abundance of mRNA encoding IL-4 and IL-6 (P < 0.05), whereas DEX decreased the expression of GPX, IL-6, IL-10 (P < 0.05). Thus, 15% dietary DDGS inclusion has the beneficial effects on immune functions for broilers to some degree.     

Performance and digestibility characteristics of finishing diets containing distillers grains, composites of corn processing coproducts, or supplemental corn oil

Three experiments evaluated the lipids in distillers grains plus solubles compared with corn or other sources of lipid in finishing diets. Experiment 1 utilized 60 individually fed yearling heifers (349 +/- 34 kg of BW) fed treatments consisting of 0, 20, or 40% (DM basis) wet distillers grains plus solubles (WDGS), or 0, 2.5, or 5.0% (DM basis) corn oil in a finishing diet based on high-moisture corn (HMC) and dry-rolled corn. Cattle fed 20 and 40% WDGS had greater (P < 0.10) G:F than cattle fed 0% WDGS. Cattle fed the 5.0% corn oil had less overall performance than cattle fed the other diets. Results from Exp. 1 indicated that adding fat from WDGS improves performance, whereas supplementing 5.0% corn oil depressed G:F, suggesting that the fat within WDGS is different than corn oil. Experiment 2 used 234 yearling steers (352 +/- 16 kg of BW) fed 1 of 5 treatments consisting of 20 or 40% (DM basis) dry distillers grains plus solubles, 1.3 or 2.6% (DM basis) tallow, or HMC. All diets contained 20% (DM basis) wet corn gluten feed as a method of controlling acidosis. No differences between treatments for any performance variables were observed in Exp. 2. The dry distillers grains plus solubles may be similar to tallow and HMC in finishing diets containing 20% wet corn gluten feed. Experiment 3 used 5 Holstein steers equipped with ruminal and duodenal cannulas in a 5 x 5 Latin square design. Treatments were a 40% WDGS diet, 2 composites, one consisting of corn bran and corn gluten meal; and one consisting of corn bran, corn gluten meal, and corn oil; and 2 dry-rolled corn-based diets supplemented with corn oil or not. Cattle fed the WDGS diet had numerically less rumen pH compared with cattle fed other treatments. Cattle fed WDGS had greater (P < 0.10) molar proportions of propionate, decreased (P < 0.10) acetate:propionate ratios, greater (P < 0.10) total tract fat digestion, and a greater (P < 0.10) proportion of unsaturated fatty acids reaching the duodenum than cattle fed other treatments. Therefore, the greater energy value of WDGS compared with corn may be due to more propionate production, greater fat digestibility, and more unsaturated fatty acids reaching the duodenum.     

Long-Term Feeding of Conjugated Linoleic Acid and Fish Oil to Laying Hens: Effects on Hepatic Histopathology,Egg Quality,and Lipid Components

The present study was conducted to investigate the effect of long-term feeding of conjugated linoleic acid (CLA) and fish oil on egg quality characteristics, production performance, liver pathology, and egg fatty acid content of laying hens. Single Comb White Leghorn laying hens (n = 112), 21 wk old, were placed in cages and randomly assigned to 4 diets (28 hens/diet, 4 replicates of 7 hens) containing 3.0% yellow grease (control), 2.75% yellow grease + 0.25% CLA (YG-CLA), 2.5% yellow grease + 0.25% CLA + 0.25% fish oil (YG-CLA-FO), and 2.75% yellow grease + 0.25% fish oil (YG-FO). The experimental diets were fed for 12 mo. Eggs were collected daily for 12 mo. Feed consumption, hen-day egg production, and feed efficiency were monitored. At the end of the trial, hepatic tissue was collected for histopathology. No effect of diet was found on feed consumption, hen-day egg production, feed efficiency, egg weight, yolk weight, shell weight, or Haugh unit. The YG-CLA and YG-CLA-FO diets produced an increase in CLA and saturated fatty acids in the egg and liver tissue with a concomitant reduction in monounsaturated fatty acids (P < 0.05). Feeding YG-CLA-FO and YG-FO increased the n-3 fatty acids in egg yolk and liver of hens (P < 0.05). No difference was observed in the number of fat vacuoles in the liver tissue. The total fat content of hepatic and abdominal fat pads did not differ among treatments (P > 0.05). Regardless of the diet, as the hens aged, egg weight, yolk weight, and egg total fat increased, and shell weight decreased (P < 0.05). These data demonstrate that eggs with increased n-3 fatty acids and CLA can be generated by minor diet modifications without affecting the production performance or health of birds.     

Haematological parameters,serum lipid profile,liver function and fatty acid profile of broiler chickens fed on diets supplemented with pomegranate seed oil and linseed oil

1. The objective of the present study was to determine effect of pomegranate seed oil (PSO) and linseed oil (LO) on haematological parameters, serum lipid profile and liver enzymes as well as fatty acids profile of adipose tissue in broilers.

2. Broilers (n = 400) were fed on diets containing graded PSO levels (0.0%, 0.5%, 1.0%, 1.5%) with or without 2% LO. After 6 weeks of feeding, 6 male broilers from each group were slaughtered and abdominal fat, liver and blood samples were collected.

3. Mixtures of pomegranate seed oil (0.5%, 1%) with linseed oil increased white blood cell level in broilers. Total cholesterol was elevated after LO supplementation whereas administration of PSO (1.5%) significantly decreased this parameter. PSO administration caused c9,t11 conjugated linoleic acid (CLA) concentration-dependent deposition in adipose tissue. By LO addition α-linolenic acid (ALA) content was enhanced, decreasing the n-6/n-3 ratio. PSO and ALA also affected oleic acid proportion in adipose tissue. Neither pomegranate seed oil nor linseed oil had any effect on liver parameters.

4. Pomegranate seed oil had no negative effects on broiler health status and can be considered as a functional poultry meat component.

     

Effect of Dietary Lipid Sources on Production of Leukotriene B by Head Kidney of Channel Catfish Held at Different Water Temperatures

Abstract

Separate and combined effects of dietary fatty acids and water temperature on the production of leukotriene B (LTB) by the head kidney of channel catfish Ictalurus punctatus were investigated. Fish were fed semipurified diets containing 7% lipid as beef tallow, corn oil, linseed oil, menhaden oil, or a mixture (1:1:1) of menhaden oil, beef tallow, and corn oil. At 28°C, fish fed corn oil produced the greatest amount of LTB, and fish fed beef tallow produced the least. At 17°C, production of LTB by fish fed the beef tallow diet was again lowest; production of LTB by fish fed the corn oil diet was highest but was not significantly different from that obtained with the mixed-oil or menhaden oil diet. Production of LTB for the other diets was intermediate. This is the first report that the head kidney of channel catfish produces LTB; this production was affected by dietary lipid sources but not by the two water temperatures tested. Production of LTB was not related to weight gain. Moreover, the pattern of LTB production does not explain survival rates of channel catfish observed in a previous experiment in response to pathogen challenge. However, LTB concentration does appear to be roughly proportional to the amount of eicosanoid precursors (arachidonic acid and eicosapentaenoic acid) previously reported for liver phospholipids of channel catfish fed diets containing different amounts of essential fatty acids.     

Effect of dietary supplementation with fermented Ginkgo-leaves on performance,egg quality,lipid metabolism and egg-yolk fatty acids composition in laying hens

The present study was conducted to investigate the effect of 3 types of fermented Ginkgo-leaves (FGL) on layer performance, egg quality, lipid metabolism, microbial populations, and egg-yolk fatty acids composition in laying hens. A total of 432 Lohmann Brown laying hens, 49 weeks of age, were randomly allocated to 4 dietary treatments with 6 replications of 18 birds each. Layers were fed basal diets (Control) or basal diets supplemented with 0.5% Ginkgo-leaves fermented with Candida utilis (CF group), Aspergillus niger (AF group), or their combined fermentation (CAF group), respectively, for an 8-week feeding trial. Compared with the control group, AF and CAF supplementation improved (P<0.05) laying rate and feed conversion ratio. Birds fed FGL (CF, AF and CAF) supplemented diet had a decrease (P<0.05) in cracked-egg rate, egg-yolk cholesterol, serum total cholesterol, triglyceride and low density lipoprotein cholesterol levels, while serum high density lipoprotein cholesterol concentrations of birds from CF and AF groups were increased (P<0.05) compared with that of the control. The concentrations of C18:1 (n-9), C18:2 (n-6), total polyunsaturated fatty acids (PUFA), ratio of PUFA/saturated fatty acids (SFA) and n-6: n-3 was increased (P<0.05 or P<0.01) with FGL supplementation. While FGL supplementation led to a decrease in total saturated fatty acids (P=0.01) concentrations. In addition, ileal and cecum Lactobacilli and Bifidobacteria populations of birds fed FGL were increased (P<0.05) compared with the control group, while ileal Escherichia coli, Salmonellas, and cecal Salmonellas were decreased in birds fed FGL. In conclusion, dietary supplementation of FGL, especially AF and CAF, in layer diets may be a feasible means of producing eggs with lower cholesterol and higher PUFA contents for health conscious consumers.