Gita Cherian

The effects of maternal and starter diet polyunsaturated fatty acid (PUFA) composition on the tocopherol (TOC) status of posthatch chicks were investigated. Fertile eggs enriched with long chain n-3, 18:3 n-3 or 18:2 n-6 PUFA were incubated. The eggs were collected from hens fed diets containing 3.5% menhaden oil (MO), linseed oil (LO), or sunflower oil (SO) and a vitamin E mix containing 400 microg/g total TOC. Posthatch chicks from MO, LO, or SO were fed starter diets containing 3.5% MO, LO, or SO along with vitamin E mix containing 48 microg/g total TOC. Tissues (liver, blood, brain) were collected on d 0 (day of hatch), 7, 14, and 21 posthatch. On d 0, MO chicks had the lowest liver and plasma TOC (P < 0.05). A rapid depletion of liver and plasma TOC was observed on d 7 and 14 posthatch (P < 0.001) and was lower in MO chicks (P < 0.05) than LO. When compared with d 0, a 98% decrease of tocopherol on d 7 was observed for chicks from all treatments. No changes due to age or diet PUFA was observed in the brain TOC status. Data showed that maternal and starter diet PUFA could alter the TOC status of chicks in early life.

We investigated the effect of dietary conjugated linoleic acid (CLA) along with n-3 polyunsaturated fatty acid (n-3 PUFA) on yolk fatty acid composition and volatile compounds in eggs that were raw (RA), hard-boiled (HB), or hard-boiled, irradiated (HBI, 2.5 kGy). Single Comb White Leghorn laying hens (n = 40) were randomly assigned to one of the four experimental diets containing 0, 0.5, 1.0, or 2.0% CLA. Menhaden oil was used as the source of n-3 PUFA. Eggs collected after 6 wk of feeding were analyzed for fatty acids and volatile compounds. The content of docosahexaenoic acid (C22:6 n-3) was reduced (P < 0.05) in eggs from hens fed the 2.0% CLA diet. Eggs from hens fed 0.5% CLA incorporated the highest concentration of docosahexaenoic acid (P < 0.05) with a concomitant reduction in arachidonic acid (P < 0.05). The yolk contents of cis-9 trans-11 CLA and trans-10 cis-12 CLA increased linearly (P < 0.05) as the dietary CLA supply increased. Total monounsaturates were reduced (P < 0.05) with an increase in saturates in yolk. No difference was observed in the total PUFA content of eggs. Total volatiles were reduced in RA eggs from 1.0 and 2.0% CLA diets. 2-Propanone, hexane, and methyl cyclopentane were the major volatiles in RA eggs and were reduced by dietary CLA at 1.0 and 2.0%. Acetaldehyde, pentane, propanol, acetic acid methyl ester, acetic acid ethyl ester, propionic acid methyl ester, 2-methylmethyl propionic acid, 2-propanone, and octane were the major volatiles in HB eggs and were reduced by 2.0% CLA (P < 0.05). No difference was observed in the acetaldehyde, pentane, propanol, acetic acid ethyl ester, octane, or total volatile content of HBI eggs.

Two experiments were conducted to evaluate the production parameters, muscle fatty acid composition, and lipid stability of birds fed four different cultivars of sorghum. Experiment 1 used ruby red and valpo red, and Experiment 2 used kinsman and mason cultivars of sorghum. The basal diet was a corn, soy, and flax meal, and sorghum cultivars were substituted at 10 or 5% in Experiments 1 and 2. No significant difference was observed for BW, feed consumption or feed efficiency (P > 0.05). The total lipids were reduced (P < 0.05) in the leg muscle of broilers fed the mason cultivar. The TBA-reactive substances (TBARS) were lower (P < 0.05) in the leg muscle of birds fed the mason cultivar when compared to kinsman or control diet. The content of n-3 polyunsaturated fatty acids were higher (P < 0.05) in the breast and leg muscles of birds fed ruby red, kinsman, and mason cultivars of sorghum.

The effect of dietary CLA along with n‐3 PUFA on yolk FA profile and hepatic lipid accumulation was investigated. Laying hens (n=40) were randomly assigned to four experimental diets containing 0, 0.5, 1.0, or 2.0% CLA. Menhaden oil was used as the source of n‐3 PUFA. Dietary CLA did not affect the total lipid content of egg yolk (P>0.05). The amounts of CLA isomers (cis‐9 trans‐11, trans‐10 cis‐12) in the egg yolk were proportional to the levels of CLA in the diet (PPPPPPPP0.05). The current study used CLA in a FFA form. The effects of using CLA in other form such as TG on avian hepatic tissue need to be investigated.

Egg components, total fat, and fatty acid content of specialty eggs were compared. One dozen eggs were collected and analyzed from each of five different brands from hens fed a diet free of animal fat (SP1), certified organic free-range brown eggs (SP2), uncaged unmedicated brown eggs (SP3), cage-free vegetarian diet brown eggs (SP4), or naturally nested uncaged (SP5). Regular white-shelled eggs were the control. A significant (P < 0.05) difference was observed in the egg components and fatty acid content in different brands. The percentage of yolk was lower (P < 0.05) in SP2 and SP4 with a concomitant increase (P < 0.05) in the percentage of white. The percentage of shell was lower (P < 0.05) in SP4 and SP5. The total edible portion was greater in SP4 and SP5. The yolk:white ratio was greater (P < 0.05) in SP3. The total lipid content was lower in SP4 eggs. The content of palmitic (C16:0), stearic (C18:0), and total saturated fatty acids were lower (P < 0.05) in SP1. No difference was observed in the content of palmitoleic (C16:1), oleic (C18:1), or total monounsaturated fatty acids. The content of n-3 fatty acids in SP2, SP4, and SP5 were similar to control eggs. The ratio of total n-6:n-3 polyunsaturated fatty acids ranged from 39.2 for SP5 to 11.5 for SP1 (P < 0.05). No difference was observed in the total polyunsaturated fatty acid content of eggs (P > 0.05).

We investigated the effects of dietary alpha-linolenic acid (LNA; 18:3n-3) of laying hens on the fatty acid composition of liver microsomes and activity of Δ-6 desaturase in hatched chicks. Laying hens were fed wheat-soybean meal-based diets with (Flax) or without ground flax (control). At Day 21 of feeding, fertile eggs were collected and incubated. On the day of hatching, chicks (n = 6) were killed, and liver microsomes were isolated and assayed for Δ-6 desaturase enzyme activity. The total n-3 fatty acids in the Flax eggs was 13.0% compared with 2.3% (P < 0.001) in the control group. LNA was the major n-3 fatty acid in the Flax eggs and constituted 10%. The long-chain n-3 polyunsaturated fatty acids (PUFA) (20:5n-3, 22:5n-3, and 22:6n-3) constituted 3.1% in Flax eggs compared with 1.5% in control eggs. Docosahexaenoic acid (22:6n-3) composed 2.1 and 1.2% in Flax and control eggs (P < 0.05), respectively. The liver microsomes of Flax chicks incorporated higher 18:3n-3, 20:5n-3, and 22:5n-3 (P < 0.05) with a concomitant reduction in 20:4n-6, 22:4n-6, and 22:5n-6 compared with control chicks (P < 0.05). The Δ-6 desaturase activities in Flax and control groups were 49.4 and 82.8 pmol/min per mg of protein, respectively (P < 0.05). These results demonstrate the role of maternal and yolk n-3 fatty acids in modulating the activity of rate-limiting enzymes for PUFA synthesis in hatched chicks.