Early Phenotype Programming in Birds by Temperature and Nutrition: A Mini-Review

Early development is a critical period during which environmental influences can have a significant impact on the health, welfare, robustness and performance of livestock. In oviparous vertebrates, such as birds, embryonic development takes place entirely in the egg. This allows the effects of environmental cues to be studied directly on the developing embryo. Interestingly, beneficial effects have been identified in several studies, leading to innovative procedures to improve the phenotype of the animals in the long term. In this review, we discuss the effects of early temperature and dietary programming strategies that both show promising results, as well as their potential transgenerational effects. The timing, duration and intensity of these procedures are critical to ensure that they produce beneficial effects without affecting animal survival or final product quality. For example, cyclic increases in egg incubation temperature have been shown to improve temperature tolerance and promote muscular growth in chickens or fatty liver production in mule ducks. In ovo feeding has also been successfully used to enhance digestive tract maturation, optimize chick development and growth, and thus obtain higher quality chicks. In addition, changes in the nutritional availability of methyl donors, for example, was shown to influence offspring phenotype. The molecular mechanisms behind early phenotype programming are still under investigation and are probably epigenetic in nature as shown by recent work in chickens.

Impact of feeding n-3 fatty acids to layer breeders and their offspring on concentration of antibody titres against infectious bronchitis, and Newcastle diseases and plasma fatty acids in the offspring

1. The impact of feeding sources of n-3 fatty acids (FA) to ISA Brown and Shaver White breeders and their offspring on antibody titres and plasma FA profile was examined.2. Breeders were fed either a control diet (CON); CON + 1% microalgae (DMA: Aurantiochytrium limacinum) as a source of docosahexaenoic acid; or CON + 2.6% of a co-extruded mixture of full-fat flaxseed (FFF) as a source of α-linolenic acid. Day-old female offspring were assigned to diets (breeder-offspring): 1) CON-CON, 2) CON-DMA, 3) CON - FFF, 4) DMA - CON, 5) DMA - DMA, 6) FFF - CON or 7) FFF - FFF, followed by a standard layer diet through 18 weeks of age (WOA) to 42 WOA.3. Antibody titres against infectious bronchitis (IBV) and Newcastle disease (NDV) were measured at six days and six WOA, and plasma FA profile was measured at 18 and 42 WOA.4. Pullets from FFF-fed breeders had higher antibody titres against IBV and NDV than pullets fed DMA (P < 0.05). Feeding FFF to offspring increased plasma ∑n-3 FA at 18 and 42 WOA, whereas feeding DMA to offspring reduced ∑n-6 FA at 18 WOA.5. In conclusion, independent of breeder strain, alpha linoleic acid (ALA) and DHA sources showed varied responses. Feeding breeders FFF increased plasma concentration of antibody titres and n-3 FA whereas DMA reduced plasma concentration of ∑n-6 FA.

Effects of feeding broiler breeder hens a coextruded full-fat flaxseed and pulses mixture without or with multienzyme supplement

The effects of coextruded full-fat flaxseed and pulses (FFF; 1:1 wt/wt) mixture on n-3 polyunsaturated fatty acids (PUFA) enrichment in egg yolk, hepatic attributes, apparent retention (AR) of components, and ceca metabolites were evaluated in broiler breeder hens. The diets were as follows: 1) corn–soybean control, 2) control diet plus 18% FFF (FFF−), and 3) FFF plus enzyme supplement (FFF+) containing galactanase, protease, mannanase, glucanase, xylanase, amylase, and cellulase activities. Twenty-six-week-old Cobb 500 broiler breeder hens were allocated to 30 identical cages (2 hens/cage) and given 1-week adaptation period. The 3 diets were assigned to 10 replicate cages based on postadaptation BW and fed based on breeder curve for 30 D. Excreta samples were collected from day 24 to 27 for determination of AR of components, and eggs were collected from day 28 to 30 for yolk polyunsaturated fatty acids analyses. On day 30, birds were weighed, killed via cervical dislocation, liver weighed, and stored for fat analyses. Ceca digesta samples were taken for concentration of short-chain fatty acids. Liver and yolk weights as well as total yolk FA were not influenced by diets (P > 0.05). Control birds had lower yolk concentration of α-linolenic acid than birds fed either FFF− or FFF+ (P < 0.01) corresponding to 7.5, 36.8, and 37.3 mg/g for the control, FFF−, and FFF+, respectively. Control birds also exhibited lower yolk concentration of docosahexaenoic acid (P < 0.01). Control birds had higher hepatic concentration of crude fat and apparent retention of dry matter and crude protein compared with either the FFF− or FFF+ birds (P < 0.05). Birds fed FFF- diet had lower ceca digesta concentration of lactic acid than control and FFF+ (P < 0.05) birds. Results showed broiler breeder hens enriched egg yolk with n-3 polyunsaturated fatty acids without effects on the liver while the supplemental enzyme did not improve the utilization of FFF.

Enriching ISA brown and Shaver white breeder diets with sources of n-3 polyunsaturated fatty acids increased embryonic utilization of docosahexaenoic acid

There is limited information on feeding egg-type chick breeders n-3 polyunsaturated fatty acids (PUFA) and its impact on hatching egg quality and embryonic fatty acid (FA) utilization. We investigated the effects of feeding brown and white egg-type chick breeders diets containing sources of n-3 PUFA on egg composition, apparent embryonic FA utilization, and intestinal FA transporter in hatchlings. Twenty-six-week-old ISA brown and Shaver white breeders were fed either 1) control (CON); 2) CON + 1% of microalgae (DMA, Aurantiochytrium limacinum) fermentation product, as a source of docosahexaenoic acid (DHA); or 3) CON + 2.60% of coextruded full-fat flaxseed and pulse mixture (FFF, 1:1 wt/wt) as a source of α-linolenic acid (ALA). Test diets had similar total n-3 and n-6:n-3 ratio. Eggs were hatched, and residual yolk (RY) samples taken for FA analyses. Apparent embryonic FA utilization was calculated by subtracting concentration of FA in RY from concentration of FA in yolk before incubation. There was an interaction between strains and diets (P < 0.05) on DHA in phospholipid and triglyceride fractions of yolk. Both n-3 PUFA sources increased DHA to a greater extent in Shaver white than in ISA brown. The interactive effect of strains and diets (P = 0.019) on embryonic utilization of ALA was such that DMA and FFF reduced ALA utilization, and this pattern was more prevalent in Shaver white birds than in ISA brown birds. There was no interaction between strains and diets on DHA utilization (P > 0.05). Embryos from hens fed n-3 PUFA sources used less total FA in phospholipid fraction (P < 0.001), and they preferentially used more DHA than CON embryos. Shaver white embryos used more (P < 0.05) ALA and DHA than ISA brown embryos. Although data suggested Shaver white had higher propensity of depositing DHA than ISA brown, irrespective of strain, feeding n-3 PUFA modified embryonic pattern of FA utilization toward utilization of DHA.

Effects of nutrition restriction of fat- and lean-line broiler breeder hens during the laying period on offspring performance, blood biochemical parameters, and hormone levels

To evaluate the effects of maternal undernutrition on the performance, blood biochemical indexes, and hormone levels of broiler chicks, two broiler breeder lines (a fat line and lean line) were given either 100% or 75% of the daily feed intake recommended by the Chinese Ministry of Agriculture from 27 to 54 wk. All hens were fed the same basal corn-soybean diet. Fertile eggs were collected and hatched. All chicks were fed the same basal diet for 56 d. Then, chick performance, blood biochemical indexes, and hormone levels were measured. The results showed that there were interactions between maternal nutrition and line for some parameters, such as the kidney index, glucose, triglyceride, insulin, glucagon, leptin, and triiodothyronine (P < 0.05). Chicks of the fat line had a lower level of serum glucose, triglyceride, albumin, glutamic-pyruvic transaminase, insulin, and thyroxin than those of the lean line (P < 0.05), but the opposite trend was seen for birth weight, heart index, leptin, and triiodothyronine (P < 0.05). Maternal undernutrition decreased the birth weight and thymus index (day 28) of offspring (P < 0.05), but these effects disappeared by day 56. Maternal undernutrition decreased glucose (day 28), urea nitrogen (day 56), creatinine (day 56), glutamic-pyruvic transaminase (day 56), creatinine kinase (day 56), and leptin (day 56) levels in the offspring's serum (P < 0.05) but increased creatinine (day 28), total protein (day 28), glutamic-pyruvic transaminase (day 28), and glucagon (day 28) levels (P < 0.05). In conclusion, different lines have different metabolic processes. Maternal nutrition restriction during the laying period did have effects on the offspring, and the compensation by offspring reduced the effect of maternal nutrition restriction.

Effect of including n-3/ n-6 fatty acid feed sources in diet on fertility and hatchability of broiler breeders and post-hatch performance and carcass parameters of progeny

Objective

The present trial was conducted to determine the influence of different dietary fatty acid (omega-3 and omega-6) sources on reproductive performance of female broiler breeders and growth performance and carcass traits of their progeny.

Methods

Two hundred and twenty, 25 weeks old Ross-308 male (20) and female (200) broiler breeders were used in the experiment for the period of 6 weeks. All birds were randomly divided into four dietary treatments (containing 2% soybean oil, 2% sunflower oil, 2% flaxseed oil, and 2% fish oil) each with five replicates of one male and ten females. Throughout this experiment hatching performance of broiler breeders, progeny growth performance and carcass parameters were recorded.

Results

The results showed that the inclusion of different fatty acid sources in female broiler breeders diet had no significant effects (p>0.05) on number of fertile eggs, post-hatch mortality, and fertility rate. The soybean oil supplemented group had significantly (p<0.05) higher late embryonic mortality compared to other three treatments.

Conclusion

It was concluded that inclusion of 2% of different sources of omega-3 and omega-6 fatty acids (especially 2% flax seed oil) in broiler breeders’ diet can reduce late embryonic mortality. The other reproductive characteristics of parents and growth and carcass characteristics of progeny remained unaltered by dietary sources of omega-3 and omega-6 fatty acids.

Thymol feed supplementation in quail alters the percentages of nutritionally relevant egg yolk fatty acids: effects throughout incubation

BACKGROUND

Polyunsaturated fatty acids (PUFA) are crucial components of egg yolk and particularly prone to oxidative damage, generating losses of nutrients for embryonic development and influencing the quality of eggs for human consumption. The aim of this study was to evaluate whether dietary thymol (a natural antioxidant) is related to changes in quail egg yolk total (T), triglyceride (TG) and phospholipid (PL) fatty acid composition at different stages of embryo development. Thus female Japanese quail (100 days of age) were assigned to one of two dietary treatments (12 individuals each): CON (basal diet) or THY (0.0016 mol thymol day^-1 per bird). After 2 weeks of supplementation, eggs were incubated and samples were obtained at 0, 4 and 16 days of embryonic development.

RESULTS

In 0 day THY eggs, α-linolenic acid and n-3 PUFA in T and TG, docosahexaenoic acid and PUFA in T and arachidonic acid in TG were increased, while saturated fatty acids (SFA) in T were reduced. From 4 days on, PUFA, n-3 PUFA and SFA from T and TG in THY eggs were found to be similar to those of CON eggs. The changes in PL throughout incubation were similar in both dietary treatments.

CONCLUSION

Thymol would provide the embryo with PUFA for synthesis/deposition in membranes and/or assign to supply energy. Additionally, thymol supplementation would be advisable for the production of healthier table eggs. © 2017 Society of Chemical Industry.

Can breeder reproductive status, performance and egg quality be enhanced by supplementation and transition of n-3 fatty acids?

The aim of this experiment was to investigate the effect of n-3 fatty acid (FA) supplemented diets on breeder performance, productivity and egg quality. Breeders (n = 480) were fed the supplemented diet from 18 weeks onwards; the inclusion level of n-3 FA was increased from 1.5% to 3.0% from 34 weeks of age onwards until 48 weeks of age. Ross-308 broiler breeders (n = 480) were fed one of four different diets: a basal diet rich in n-6 FA (control diet) or one of three diets rich in n-3 FA. For the n-3 FA diets, eicosapentaenoic acid (EPA, 20:5 n-3) and docosahexaenoic acid (DHA, 22:6 n-3) were fed to the broiler breeders at different ratios formulated to obtain EPA/DHA ratios of 1/1, 1/2 or 2/1. Differences in performance, reproduction and egg quality parameters due to n-3 supplementation were noted more for the 1.5% followed by the 3.0% fed broilers than their 1.5% supplemented counterparts. Egg weight (p < 0.001) and egg mass (p = 0.003) were significantly lower and feed conversion (p = 0.008) significantly higher for the n-3 FA (at 3.0% inclusion level) fed broilers compared to the control group. For the EPA- and DHA-fed breeders, a higher proportional abdominal fat percentage (p = 0.025) and proportional albumen weight (%) (p = 0.041) were found respectively. Dietary treatments did not affect reproduction. It can be concluded that the results of the present experiment indicate no significant differences between treatments at 1.5% inclusion levels. However, increasing this level to 3.0% is not recommended due to the rather negative effects on the measured parameters. It should be further investigated whether these adverse effects were obtained due to (i) the higher supplementation level, (ii) combining a supplementation level of 1.5% with 3% or (iii) the duration of supplementation.