Varying isoleucine level to determine effects on performance, egg quality, serum biochemistry, and ileal protein digestibility in diets of young laying hens.

To ascertain an appropriate level of isoleucine for LSL-LITE layers (23- to 30-week-old), diets containing total isoleucine concentrations (levels) of 0.66 (Control), 0.69, 0.72, 0.75, 0.78, 0.81, and 0.84% were fed as 7 treatments (2730 kcal/kg metabolizable energy) x 7 replicates x 10 birds per replicate. Significance for performance, egg quality, serum biochemistry, and ileal digestibility of protein was determined at P ≤ 0.05. Level, week, and level*week (L*W) were significant for production, egg mass, and feed intake. Level and week were significant for FCR. Week was significant for weight gain. Level was significant for egg weight, specific gravity, and shell thickness; week was also significant for these external egg parameters as well as shape index and proportional shell thickness. L*W was significant for all except shape index. For internal egg measurements, level was significant for proportional yolk, proportional albumen, yolk index, and yolk:albumen. Week was significant for internal egg parameters while L*W significantly affected Haugh unit, proportional albumen weight, yolk index, albumen index, and yolk color. Level was significant for globulin and glucose in serum. Isoleucine at 0.72%, 0.81%, and 0.84% produced the lowest FCR, an important standard in the poultry industry. Considering the low FCR of 1.45 and cost for inclusion as a dietary ingredient, 0.72% isoleucine was chosen for further studies with varying quantities of other branched chain amino acids in diets for young laying hens.

Effects of prepartum dietary protein level and feed intake on postpartum lactation performance and feeding behavior of multiparous Holstein dairy cows.

An experiment was conducted to determine the effects of low and high metabolizable protein (MP) diets when fed for ad libitum and controlled intake during the prepartum period on postpartum lactation performance and feeding behavior of dairy cows. Thirty-six multiparous Holstein cows were blocked by parity, expected calving date, and previous lactation milk yield at -21 d relative to expected calving and were randomly assigned to 1 of 4 close-up period dietary treatments providing low MP (LMP) or high MP (HMP) diets with controlled intake (CNI) or ad libitum intake (ALI). The concentrations of MP were 65 and 90 g/kg dry matter for LMP and HMP diets, respectively, whereas intake was controlled to supply 100 and 160% of the NRC (2001) energy requirements for CNI and ALI groups, respectively. The concentration of net energy for lactation (NEL) in the treatment diets was 1.50 Mcal/kg. All cows were fed a similar lactation diet after calving (1.50 Mcal/kg of NEL and 83.3 g/kg of MP). The HMP diet increased dry matter intake during the first 3 wk and tended to increase dry matter intake over the 9 wk of lactation. Meal size and eating rate increased in the ALI cows during the prepartum period. Meal frequency increased with the HMP diet during the postpartum period. Milk yield increased by 15.2% with the HMP diet over the 9 wk of lactation. The HMP diet increased energy-corrected milk (ECM) yield in CNI versus ALI cows, whereas the LMP diet increased ECM yield in ALI versus CNI cows over the 9 wk of lactation. The increase in ECM yield of LMP-ALI versus LMP-CNI cows was supported by greater body condition loss and serum ß-hydroxybutyrate over the 9 wk of lactation. Taken together, these data indicate that prepartum controlled intake of a high protein diet can provide the benefits of both strategies.

Interactive effects of threonine levels and protein source on growth performance and carcass traits, gut morphology, ileal digestibility of protein and amino acids, and immunity in broilers.

An experiment was executed to test the hypothesis that supplementation of dietary threonine (d-Thr), above NRC recommendation to diets containing poorly digestible protein source (PS) may compensate its detrimental effects on overall performance of broilers. In total, nine hundred 1-day-old mixed sex broilers (Ross-308) were randomly distributed over 6 (2 × 3) experimental diets comprising 5 replicates of 30 broilers each for 35 d. The experimental diets contain either soybean meal (SBM) or canola meal (CM) with 3 levels (100, 110, and 120% of NRC recommendation) of d-Thr. During the course of the trial (0 to 35 D), interactions (P < 0.05) between PS and d-Thr were observed for feed intake (FI), body weight gain (BWG), feed conversion ratio (FCR), carcass, and gut health parameters. The broilers fed recommended level (100%) of d-Thr had 7 and 5% poorer FCR compared with those fed diets with 110 and 120% d-Thr, respectively. For villus height (VH), an interaction (P = 0.007) was found between PS and d-Thr level. Broilers consuming SBM diets had 22% longer villi, 10% deeper crypts, and 30% greater VH to crypt depth ratio (VCR) compared to those fed CM. The broilers fed 110% d-Thr diets had 9% lower crypt depth (CD) and 15% greater VCR compared with those fed diets containing NRC recommended levels. CM resulted in 9% lower protein digestibility with lower (P < 0.05) of some AA, whereas it was improved by 7% in broilers fed 120% d-Thr supplemented diets. The bursa and spleen weights were positively affected (P < 0.001) by PS. Threonine supplementation (10%) resulted in 25% greater thymus, 18% heavier bursa, and 30% greater infectious bursal disease titer. In conclusion, supplementation of d-Thr, above NRC recommendation, resulted in a better growth performance and carcass traits, improved ileal digestibility of protein and amino acids, better gut health, and immunity in broilers.

Exploring nutritive profile, metabolizable energy, protein, and digestible amino acids contents of indigenous protein sources of different locations for male broilers.

2 experiments were conducted to explore nutrient composition, AME, AMEn, standardized ileal digestibility (SID) of CP, and amino acids (AA) of 4 indigenous protein sources including canola meal (CM), rapeseed meal (RSM), guar meal (GM), and sunflower meal (SFM) collected from 2 different locations, Multan (MUL; n = 3) and Sukkur (SKR; n = 3), of Pakistan. Higher (P < 0.05) dry matter (DM), CP, and gross energy (GE), whereas lower (P < 0.05) ash contents were found in SKR, CM, and RSM compared with those from MUL. The MUL GM had higher (P < 0.05) crude fiber (CF) and CP, whereas lower (P < 0.05) GE compared with those from SKR. The SFM from MUL had higher DM, whereas lower CF and CP contents than SKR. In the first experiment, 216 21-d-old male broilers (Ross 308) were distributed over 8 test diets (4 ingredients × 2 locations) and 1 basal diet, with 4 replicates containing 6 birds each (9 × 4 × 6), in a complete randomized design to determine AME and AMEn. The results indicated higher (P < 0.05) AME and AMEn in MUL CM than SKR. In the second experiment, 216 21-d-old male broilers (Ross 308) were raised in 36 cages (6 birds each) to determine SID of CP and AA in a complete randomized design. 8 test diets (4 ingredients × 2 locations) and a protein-free diet, with 4 replicates each, were tested. The SID of CP and some AA were higher (P < 0.05) in MUL CM and RSM than SKR. The SKR GM had a higher (P < 0.05) SID of CP, arginine, methionine, threonine, valine, and cysteine compared with that from MUL. The SFM from MUL had higher (P < 0.05) SID of CP, arginine, histidine, methionine, valine, alanine, aspartate, cysteine, and serine than SKR. In conclusion, major differences do exist between CM, GM, RSM, and SFM from different locations in terms of nutrients, AME, digestible CP, and AA contents for male broilers.

Comparison of oil and fat supplementation on lactation performance of Nili Ravi buffaloes.

The effects of feeding rumen-inert fat sources on production responses of lactating dairy cows have been well reported but less thoroughly described in lactating dairy buffalo. The objective of this study was to investigate the effect of oil and 2 different rumen-inert fat sources on dry matter intake, milk yield, milk composition, and milk fatty acid (FA) profile in Nili Ravi buffalo. Twelve multiparous mid-lactating Nili Ravi buffaloes received 4 treatments in a 4 × 4 Latin square design with a period length of 21 d. The treatments were (1) the basal diet without supplementation of oil or fats (CTRL), (2) the basal diet supplemented with canola oil (CO), (3) the basal diet supplemented with calcium salts of palm FA (Ca-FA), and (4) the basal diet supplemented with high palmitic acid (PA). Dry matter intake was decreased by 4.4% in the CO compared with Ca-FA and PA. Milk yield and milk fat yield were increased by 7.8 and 14.3%, respectively, in CO, Ca-FA, and PA compared with the CTRL. Milk fat content increased by 7.5%, whereas milk fat yield tended to increase with the supplementation of Ca-FA and PA compared with CO. No effect on milk yield and milk composition was observed in Ca-FA versus PA treatments. The yield of medium-chain FA was increased by Ca-FA and PA versus CO. The CO treatment increased the yield of long-chain FA compared with Ca-FA and PA treatments. Plasma glucose level was higher in CO, Ca-FA, and PA compared with the CTRL. In conclusion, feeding rumen-inert fats in the lactating buffalo diet proved to be a useful strategy to increase the 3.5% fat-corrected milk yield due to the higher milk fat content in this study.

Assessing behavior in Aseel pullets under free-range, part-time free-range, and cage system during growing phase.

The objective of this study was to explore the effects of free-range (FR), part-time free-range (PTFR), and cage system (CS) on behavioral repertoire in Lakha (LK), Mushki (MS), Peshawari (PW), and Sindhi (SN) varieties of Aseel chicken during the growing phase (9 to 18 wk of age). In total, 144 Aseel pullets were allotted to 12 treatment groups in a 3 × 4 (rearing system × Aseel variety) factorial arrangement, according to a randomized complete block design (RCBD). Each treatment group was replicated 3 times with 4 birds in each replicate (12 birds per treatment group). The pullets were randomly marked weekly for identification, and their behavior was observed through the focal animal sampling method. Time spent on different behavioral activities was recorded and converted to a percentage. The data were analyzed using 2-way ANOVA under a factorial arrangement using SAS 9.1, and the behavioral parameters were evaluated. The results indicated greater (P < 0.05) sitting, standing, drinking, preening, and aggressiveness in CS; walking, running, and jumping in PTFR; and foraging and dustbathing in both FR and PTFR, whereas feather pecking was found to be reduced in FR compared with PTFR and CS. Among varieties, PW showed the least feeding/foraging and feather pecking behavior, and greater standing, running, and jumping behavior (P < 0.05). However, SN spent less time in walking and preening, and more time in sitting, drinking, and aggressiveness. Dustbathing was found to be similar in all Aseel varieties (P = 0.135). In conclusion, the PTFR system could be suggested as a substitute for conventional housing systems because it better accommodates normal behavior in Aseel pullets.

Blood biochemistry and immune response in Aseel chicken under free range, semi-intensive, and confinement rearing systems.

A study was conducted to investigate the effects of 3 different rearing systems [free range ( FR: ), semi-intensive ( SI: ), and confinement ( CF: )] on blood biochemical profile and immune response in 4 varieties of Aseel chicken [Lakha ( LK: ), Mushki ( MS: ), Peshawari ( PW: ) and Sindhi ( SN: )] for 10 wk duration (7 to 16 wk). At the age of 6 wk, in total, 180 cockerels were assigned to 12 treatment groups, 3 (rearing system) × 4 (Aseel chicken variety) factorial arrangement in 7 randomized complete blocks, replicated 3 times with 5 birds in each replicate (45 birds of each variety; 60 birds in each rearing system; 36 total replicates). Blood samples were collected through brachial vein at the end of wk 16. After laboratory analysis, the recorded data for blood biochemical profile and immune response were analyzed by using 2-way ANOVA under factorial arrangement. The results showed higher (P < 0.05) plasma glucose and total protein in birds under CF. Titer against Newcastle disease virus ( NDV: ) and infectious bronchitis virus ( IBV: ) was found to be greater (P < 0.05) in SI and FR, respectively. Peshawari birds indicated higher (P < 0.05) concentration of glucose, total protein, albumin, uric acid, creatinine, and titers to NDV and IBV. Birds of LK and SN varieties also indicated maximum antibody titer against NDV and IBV, respectively. Cholesterol level was found to be greater (P < 0.05) in birds of LK and SN. Interaction of SN with FR revealed maximum (P < 0.05) cholesterol whereas interaction of PW with SI indicated maximum antibody titer against NDV. The results highlight that CF rearing system expediently affects glucose and total protein levels in birds; SI and FR confer maximum antibody titers to NDV and IBV. Birds of PW variety indicated higher glucose, total protein, albumin, uric acid, and creatinine, the lowest cholesterol under FR and the enhanced antibody titer against NDV and IBV.

Influence of weaning regimen on intake, growth characteristics and plasma blood metabolites in male buffalo calves.

Experiment was conducted to evaluate the effect of weaning age on growth performance, feed intake, feed efficiency (FE) and blood metabolites in Nili-Ravi male buffalo (Bubalus bubalis) calves. Twenty-four male buffalo calves were assigned to one of the three treatment groups: continuous milk feeding (CMF), limited milk feeding (LMF) and early weaning (EW), and weaned off milk at 12, 10 and 8 weeks of age, respectively. For the first 3 days after birth, calves in all three treatments were fed colostrum, and were then moved to individual milk feeding at 10% of BW for the next 6 weeks. Thereafter, the provision of milk to the CMF group was gradually tapered to zero through week 12, using week 6 intakes as a base. The LMF calves were fed milk at 7.5%, 5.0%, 3.5%, and 1.5% of BW during weeks 7 to 10, respectively. Lastly, calves in the EW group were fed milk at 5.0% and 2.5% of BW at weeks 7 and 8, respectively. Calf starter (CS) feed was also provided ad libitum from weeks 2 to 12 and individual intakes were recorded on a daily basis. Blood samples were taken from weeks 6 to 12, on a weekly basis; whereas, the BW, heart girth, withers height and hip width were measured at the start of experiment and later on a weekly basis. Weight gain, average daily gain, and body measurements were the same across all three groups. Milk intake was lower (P < 0.05), whereas CS intake was greater (P < 0.05) in the EW calves compared with the other treatment groups. Dry matter intake was greater (P < 0.05) in the EW and LMF calves compared with the CMF calves. The FE was greater (P < 0.05) in the CMF calves compared with the LMF and EW treatment groups. Blood glucose concentration was similar among the treatments; however, blood urea nitrogen was greater (P < 0.05) in the EW calves compared with the CMF and LMF groups. Plasma concentration of non-esterified fatty acids was higher (P < 0.05) in the EW calves compared with the CMF calves. In light of these results, it is evident that buffalo calves can be successfully weaned as early as 8 weeks of age without negatively affecting their growth performance.

Growth Performance, Carcass Traits and Serum Mineral Chemistry as Affected by Dietary Sodium and Sodium Salts Fed to Broiler Chickens Reared under Phase Feeding System.

A basal diet (0.8 g/kg dNa) was formulated in which each of the two sources (NaHCO3 and Na2SO4) were supplemented in such a way to attain four levels (1.7, 2.6, 3.5, and 4.4 g/kg) of total dNa, respectively, under 4×2 factorial arrangement. Eight dietary treatments were replicated four times, with 40 birds in each replicate (n = 1,280). The diets supplemented with Na2SO4 to attain higher levels of dNa showed highest BW gain and feed intake (FI) during d 1 to 10 (interaction effects) while 2.6 g/kg dNa exhibited improved BW gain and gain:feed (FG) during d 11 to 20. Linear rise in daily water intake (DWI) was associated with diets containing increasing dNa during d 1 to 42 (p≤0.036). During the first 10 d, DWI:FI was found highest in NaHCO3 diets while Na2SO4 diets showed highest DWI:FI during last 10 d of the experiment (p≤0.036). Increasing dNa and changing Na2SO4 with NaHCO3 salt increased pH and resulted in poor growth performance. Dressing weight (p≤0.001) and abdominal fat (p≤0.001; quadratic effect) were reduced, whereas breast (p≤0.001) and thigh (p<0.001) weights were aggravated with increasing dNa (linear effects). Present findings suggested higher levels of dNa from Na2SO4 as the supplemental salt in broiler diets would produce better growth performance, especially in first ten days of life, and improve carcass and body organ characteristics.

Growth Performance, Carcass Characteristics and Plasma Mineral Chemistry as Affected by Dietary Chloride and Chloride Salts Fed to Broiler Chickens Reared under Phase Feeding System.

Requirements of dietary chloride (dCl) and chloride salts were determined by using 4×2 factorial arrangement under four phase feeding program. Four levels (0.31, 0.45, 0.59 and 0.73%) and two sources (NH4Cl and CaCl2) of the dCl were allocated to 1,472 chicks in eight dietary treatments in which each treatment was replicated four times with 46 birds per replicate. The four phase feeding program was comprised of four dietary phases: Prestarter (d 1 to 10), Starter (d 11 to 20), Grower (d 21 to 33) and Finisher (d 34 to 42); and diets were separately prepared for each phase. The cations, anions, pH, dissolved oxygen (DO), temperature, electrical conductivity (EC), total dissolved solids (TDS) and salinity were analyzed in drinking water and were not affected by dietary treatments. BW gain (BWG; p≤0.009) and feed:gain (FG; p≤0.03) were improved in CaCl2 supplemented diets during d 1 to 10. The maximum response of BWG and FG was observed at 0.38% and 0.42% dCl, respectively, for d 34 to 42. However, the level of dCl for BWG during d 21 to 33 (p≤0.04) and d 34 to 42 (p≤0.009) was optimized at 0.60% and 0.42%, respectively. The level of dCl for optimized feed intake (FI; p≤0.006), FG (p≤0.007) and litter moisture (LM; p≤0.001) was observed at 0.60%, 0.38% and 0.73%, respectively, for d 1 to 42. Water intake (DWI) was not affected by increasing dCl supplementation (p>0.05); however, the ratio between DWI and FI (DWI:FI) was found highest at 0.73% dCl during d 1 to 10 (p≤0.05) and d 21 to 33 (p≤0.009). Except for d 34 to 42 (p≤0.006), the increasing level of dCl did not result in a significant difference in mortality during any phase. Blood pH and glucose, and breast and thigh weights (percentage of dressed weight) were improved while dressing percentage (DP) and gastrointestinal health were exacerbated with NH4Cl as compared to CaCl2 supplemented diets (p≤0.001). Higher plasma Na(+) and HCO3 (-) and lower Cl(-) and Ca(++) were observed in NH4Cl supplemented diets (p≤0.001). Increasing supplementation of dCl increased plasma Cl(-) (p≤0.04; quadratically) and linearly reduced plasma K(+) (p≤0.001), Ca(++) (p≤0.003), HCO3 (-) (p≤0.001), and Na(+) (p≤0.001; quadratically). Consequently, higher requirements of dietary chloride are suggested for feed intake; nevertheless, lower levels of dietary chloride are sufficient to support optimal BWG and FG with increasing age. The NH4Cl supplemented diets ameliorate breast and thigh meat yield along with overall energy balance (glucose).

Response of maternally isolated rock pigeons (Columba livia domestica) to different dietary concentrations of mannan-oligosaccharide.

Prebiotics are being used as an alternative to antibiotic growth promoters in poultry industry with a variable degree of success. This trial was conducted to investigate the effect of dietary mannan-oligosaccharide (MOS) supplementation on growth performance, selected colonic bacterial population, and immune response in maternally-isolated rock pigeons. The pigeons (n = 36) were randomly distributed in 4 treatment groups (n = 9 per group) with 3 replicates or pens (n = 3) in each group. Birds were fed either a corn/wheat-based basal diet (control group/CON) or the same diet supplemented with 0.1%, 0.2%, or 0.5% MOS for 35 d. On d 35, birds were killed to collect visceral organs, colonic contents, and serum. Colonic contents were used to enumerate selected microbiota and serum was used to detect antibody titer against the Newcastle disease virus. Cell-mediated immunity was determined by measuring the skin thickness following 2,4-dinitrochlorobenzene challenge. Results showed that supplementation did not affect the BW of birds. During wk 4, feed intake was significantly higher in the 0.2% (187.9 ± 0.86) and the 0.5% (186.4 ± 0.86) MOS-supplemented groups compared with the CON group (180.7 ± 0.86). Gizzard weights (with and without digesta) were significantly higher in the MOS 0.1% (10.67 ± 0.33 and 8.22 ± 0.26) and the MOS 0.2% (9.91 ± 0.33 and 7.94 ± 0.26) groups compared with the CON group (7.56 ± 0.33 and 6.25 ± 0.26). Small intestinal weight was significantly higher in the MOS 0.2% group (14.71 ± 0.56) compared with the CON group (9.56 ± 0.56). Lengths of small intestine (MOS 0.1% = 92.56 ± 1.69, MOS 0.2% = 90.79 ± 1.69, MOS 0.5% = 90.57 ± 1.69) in all the MOS-fed groups and large intestine in the 0.1% (3.50 ± 0.02) and the 0.5% (3.47 ± 0.02) MOS-fed groups were significantly higher than the CON group (small intestine = 77.63 ± 1.69, large intestine = 2.41 ± 0.02). Weights of heart, liver, pancreas, and large intestine remained unaffected. Feeding of MOS did not influence colonic population of Escherichia coli, Clostridia, and Bifidobacteria. Lactobacilli count was significantly higher in the 0.2% MOS-fed group (9.77 ± 0.12) compared with the CON group (9.19 ± 0.16). Mannan-oligosaccharide did not affect the immune response of the birds as antibody titer against the New Castle disease virus and the cell-mediated immunity remained similar in all the treatment groups. In conclusion, dietary MOS supplementation influenced only the colonic lactobacilli population without any apparent effects on the production performance in growing pigeons.

Sensory evaluation and consumer acceptance of eggs from hens fed flax seed and 2 different antioxidants.

The sensory attributes and consumer acceptance of eggs from flax seed-fed hens were evaluated by trained and untrained panelists. Hens were fed diets containing 0% flax seed (control), 10% flax seed (flax), 10% flax seed+100 IU/kg of vitamin E (flax+α-tocopherol), or 10% flax seed+100 mg/kg of butylated hydroxytoluene (BHT) (flax+BHT). Fresh eggs collected within 24 h were hard-boiled, coded, and were offered to trained panelists in 4 testing sessions. Sensory traits evaluated were aroma, flavor, off-flavor, and overall difference. The trained panelists rated flax, flax+α-tocopherol, and flax+BHT eggs to be different from control eggs (P<0.001). In a second study, sensory attributes were tested by untrained panelists. The majority (75 to 80%) of the panelists could not distinguish flax seed-fed versus control eggs for aroma and flavor. A consumer preference test was also conducted to gauge end-user response to flax seed-fed eggs. Consumer acceptance testing did not find any significant difference (P>0.05) between control and flax seed-fed eggs. These results suggest that flax seed when incorporated at 10% in the layer diet can produce eggs that are acceptable to untrained panelists and consumers. However, trained panelists are able to detect differences in flavor, aroma, and off-flavor and overall difference in eggs from hens fed flax seed. Antioxidant supplementation (vitamin E, BHT) did not enhance the acceptability of flax seed-fed eggs by trained panelists.

Oxidative stability and lipid components of eggs from flax-fed hens: effect of dietary antioxidants and storage.

An experiment was conducted to investigate the effect of dietary antioxidants and storage on fatty acid profile, oxidative stability, and vitamin E concentration of n-3 fatty acid-enriched eggs. Eggs (384, 48/diet) were collected from ISA Brown layers fed diets containing corn-soy (control) with 100 g/kg of flax seed and 2 types of antioxidants [alpha-tocopherols (alpha-TOC) and butylated hydroxytoluene (BHT)] at 0, 50, 100, or 150 IU or mg/kg. Eggs were stored at 4 degrees C. On d 0, 20, 40, and 60 of storage, 2 eggs were selected randomly from each replicate (totaling 12 eggs per treatment) and analyzed. Eggs from hens fed flax had increased alpha-linolenic (18:3n-3), eicosapentaenoic (20:5n-3), and docosahexaenoic acids (DHA, 22:6n-3) and decreased arachidonic acid (20:4n-6) and total n-6:n-3 ratio when compared with control eggs (P<0.05). The n-6:n-3 fatty acid ratio was lowest in the flax+50 IU of alpha-TOC, flax+100 IU of alpha-TOC, and flax+BHT supplemented group when compared with the flax group (P<0.05). With the exception of flax+100 mg of BHT, addition of antioxidants led to a reduction in palmitic acid in fresh eggs (P<0.05). During the first 20 d of storage, over a 17% reduction in total n-3 fatty acids was observed in eggs from flax+50 mg of BHT supplemented groups (P<0.05). Docosahexaenoic acid was the predominant long-chain n-3 fatty acid in egg and was stable during storage in the control, flax, flax+100 IU of alpha-TOC, flax+150 IU of alpha-TOC, and flax+150 mg of BHT groups. However, antioxidant supplementation had no effect on DHA upon storage in flax+50 IU of alpha-TOC and flax+50 mg of BHT eggs where over 13 to 17% reduction in DHA content was observed during 20 to 60 d of storage (P<0.05). Inclusion of alpha-TOC led to over 4.5- to 12-fold increases in alpha-TOC in eggs. Egg storage for 40 d or longer led to over 50% reduction in egg alpha-TOC (P<0.05). Feeding flax seeds led to an increase in TBA reactive substances in eggs (P<0.05). alpha-Tocopherol was better in preventing lipid oxidation than BHT at d 0 of storage. However, neither had a significant effect on egg TBA reactive substances upon 60 d of storage (P>0.05). These studies demonstrate that the level and type of antioxidants and duration of egg storage significantly affected the fatty acid profile, alpha-TOC status, and oxidative stability of chicken eggs.

Influence of moisture content of forage diets on intake and digestion by sheep.

To determine the effect of forage moisture content on intake and digestion kinetics in sheep, a metabolism trial was conducted using 16 mature wethers (44 kg BW) in a completely randomized design. Forage was harvested at two maturities in early spring from a naturalized pasture composed of temperate grass and legume species. Herbage was harvested at either 8 (early) or 16 cm (late) in height and fed after freezing (high-moisture) or as a dried hay. Intakes of DM (grams/[kilogram BW.75.day]), NDF, ADF, and CP (grams/day) (P < .05) and coefficients for DM, NDF, and ADF digestibilities were greater (P < .01) for hay than for high-moisture forage. Mean particulate retention times (MRT) were shorter (P < .05) for high-moisture forage (23.3 h) than for hay (30.7 h) diets. Early-harvested forages had shorter (P < .05) MRT values (23.9 h) than late-cut forages (30.1 h). Fractional passage rates of 1-mm nylon particles of specific gravity (SG) .90, 1.14, and 1.32 through the alimentary tract were influenced by moisture content of the forage (P < .10) and were faster for frozen forages and increased (P < .01) with an increase in SG. Nitrogen retention was greater (P < .01) for the hay than for the high-moisture forage. In situ DM digestion rates, determined using four ruminally fistulated wethers, showed no differences (P = .67) among forages. The results of this study indicate that differences in digestibilities between hays and high-moisture forages are most likely due to differences in digesta passage rates.