Performance Of White Leghorn Hens Research Articles

Effect of boron supplementation on laying performance of White Leghorn hens fed diet with and without adequate level of calcium.

This study was conducted in White Leghorn layers to ascertain the effect of boron (B) supplementation to calcium (Ca) inadequate diet under standard managemental practices. A total of 80 commercial White Leghorn hens, 25weeks old with a uniform body weight, were randomly assigned to one of the 4 groups of 20 hens/replicates in each dietary group viz., normal calcium (NC)/Ca adequate, low calcium (LC)/Ca-inadequate, normal calcium with 40ppm B (NCB) and low calcium with 40ppm B (LCB). Dietary level of Ca was maintained at two levels, 100 (normal) and 90% (inadequate) of the requirement. Supplementation of B at 40ppm improved (P < 0.01) egg production of layers from third month of trial as compared to un-supplemented group. Feed conversion ratio of layers was positively (P < 0.05) influenced by B supplementation in Ca-inadequate diet. Egg shell thickness of layers was found to be higher (P < 0.001) in groups supplemented 40ppm B, irrespective of the level of Ca in the diets. Cracked egg production was also significantly (P < 0.01) lower in B-supplemented groups compared to Ca-inadequate group. Boron supplementation improved Ca retention irrespective of dietary Ca level. Low-Ca diet without boron supplementation resulted in lower retention (P < 0.05) of magnesium and boron. It is concluded that supplementation of 40ppm B to Ca-inadequate diet ameliorated the lower laying performance in layers and confirms the usefulness of B in such abiotic stress situations.

Influencia del hidrolizado de proteínas en el comportamiento bioproductivo en gallinas de la línea L1 White Leghorn

The objective of this study was to evaluate the influence of protein hydrolysates (PH), as a nutritional supplement, in the bioproduction performance of White Leghorn hens. Thirty-nine-week old light line hens were assessed during six weeks. Two treatments (T) were designed involving 320 hens each (three replications of 40 hens each). In T1, each bird received 2 ml of PH daily; the birds in T2 were not offered the product. The following variables were controlled: bioproduction (total egg production, egg-laying percentage, total feed intake, mass conversion, viability, and caused mortality); incubation indicators (eggs to plant, incubation percentage, hatchability, and top quality chicks) and; quality (feed intake by top quality chicks, and top quality chicks per hen). The hens that received the PH showed significant differences in the laying, incubation, and hatchability percentage, as well as mass conversion, and the egg to plant ratio. They showed better performance in quality indicators. It is concluded that the use of PH in light line hens improves their bioproduction performance, as well as the indicators of to incubation, egg to plant ratio, and hatchability; its use also reduces by approximately 100 grams the necessary food intake to obtain top quality chicks.

Influence of Prelay Treatment and Dietary Protein Level on the Reproductive Performance of White Leghorn Hens

Two experiments were undertaken to study the influence of prelay diet treatment on subsequent laying performance. Feeding either a conventional laying or growing diet or diets containing essentially only wheat bran from 18 to 21 wk resulted in little grower diet carryover effect beyond 24 wk of age, although the wheat bran diets resulted in a marked drop in body weight of the pullets during the prelay treatment. Similar performance was noted for pullets in a second experiment in which prelay treatments consisted of feeding just corn or wheat bran from 18 to 20 wk of age. In interpreting the results of the present study, it is important to consider the fact that “mature pullet weights” were obtained before the prelay diet treatments were employed. Where prelay diet treatments have had significant effects on laying house performance, in most cases, immature or underweight pullets were involved.Feeding hens low-protein diets (13 versus 17%) from 20 to 44 wk of age resulted in similar egg production; however, egg weight and thus egg mass were slightly reduced with the lower protein diet. There was no laying by growing treatment interaction. The importance of good pullet weight at the start of the production cycle and the subsequent performance of such pullets fed low-protein diets is discussed.

Effect of vermiculite on productive performance of White Leghorn hens in a controlled feeding system

Feeding ad libitum of laying hens was compared with controlled feeding in terms of rate of lay, feed efficiency, body weight gain, mortality, egg size and quality. Birds were assigned to four treatment groups: (A) basal diet ad libitum; (B) 5% less feed than the standard requirement; (C) and (D) restricted as for Treatment B, but with 4% and 6% of the basal diet, respectively, replaced with vermiculite. The treatments were applied for 1 year from 151 to 515 days of age. Body weight gain of restricted birds (Groups B, C and D) was less than that of Group A, but the latter group attained 50% egg production 3–9 days later than the restricted groups. Egg production per 100 hen-days was 67.2, 68.2, 71.0 and 69.1, and egg mass output was 3.74 kg, 3.86 kg, 4.10 kg and 3.97 kg for Groups A, B, C and D, respectively. Group C laid significantly more ( P < 0.05) eggs than Groups A and B. All restricted feeding groups produced fewer abnormal eggs and required 610–870 g less feed per kilogram of egg production. The vermiculite groups (C and D) ate 21–22% less feed than Group A ( P < 0.05). The best results for egg production and feed utilization were from Group C in which 4% of the basal diet was replaced with vermiculite.

The Effects of Fluorescent Light Sources on the Performance of White Leghorn Hens

Experiments were conducted to examine the effect of fluorescent light sources on egg production, egg weight, and egg sizing as percentage large and above. In an initial experiment, dimmed incandescent (INC), undimmed warm-white circle (CF), and dimmed cool-white strip fluorescent (SFC) bulbs were compared. A subsequent experiment was similar to the initial one with the exception that warm-white strip fluorescent (SFW) bulbs replaced cool-white bulbs.For the parameters recorded, birds under INC and CF lights in Experiments 1 and 2 responded similarly. During Periods 8, 12, and 13 of Experiment 1, birds subjected to SFC light produced significantly more eggs (P<.05) than INC, but there was no effect on egg size or grade. In contrast, SFW only produced a significant increase (P<.05) in egg production during the first period. In addition, there were significantly fewer (P<05) eggs grading as percentage large and above from the SFW-lighted birds during Periods 2, 3, and 7. The fluorescent light sources consumed 17 to 30% of the power used by the INC bulbs.In Experiments 3 and 4, Phillips 7-W (PL-7) fluorescent bulbs were compared with CF lighting. There were few significant differences in egg production (Experiment 4), and egg size and weight were similar for both CF and PL-7 birds. Power usage was also similar during the measurement period of the first eight periods of Experiment 3.It was concluded that warm-white fluorescent light sources can be used in place of INC. The CF and PL-7 lights produced the most consistent results in bird productivity. Significant power savings occurred from use of any of the three fluorescent light sources compared with use of INC.

Research Note: Effect of Preincubation Storage of Hatching Eggs on Subsequent Performance of White Leghorn Hens

Eggs from three strains of White Leghorn hens were stored up to 21 days prior to incubation in 1964 and 1965. Eggs stored longer than 7 days were packaged in Cryovac2 bags with the air evacuated (1964) or flushed with nitrogen (1965) and held at about 12 C and 80% relative humidity. Each year, all eggs were set together and incubated at 37.5 C (29.5 C wet bulb). At 18 days of incubation, eggs were candled, apparently infertile eggs removed, and incubation continued at 37.0 C (32.5 C wet bulb). Hens were housed at 147 days in floor pens in 1964 and in individual cages (20 × 41 cm) in 1965.Preincubation storage reduced hatchability of apparently fertile eggs. Preincubation storage affected only housing body weight (1964), egg weight (1964, 1965), Haugh units (1964, 1965), and blood spots (1965). Effects of preincubation storage of hatching eggs on hens’ subsequent performance do not appear important enough to offset the advantage of storing hatching eggs for up to 3 weeks in experiments and breeding programs where it is advantageous to reduce hatch effects or to offset the management advantages of fewer hatches.

The effects of dietary level of sunflower seeds and lysine on egg quality and laying performance of White Leghorn hens

AbstractIn a 4×2 factorial experiment, 672 White Leghorn hens were given diets with four levels (0, 10, 20 and 40 g kg−1) of sunflower seeds and two levels (7.0 and 8.0 g kg−1) of dietary lysine from 43 to 67 weeks of age. The inclusion of increasing levels of sunflower seeds in the diet increased (P&lt;0.01) egg weight and reduced (P&lt;0.01) albumen height and Haugh units of eggs. The diets with sunflower seeds increased (P&lt;0.01) the proportion of 65 g grade eggs and reduced (P&lt;0.01) that of 55 g and 50 g grades. Rate of egg production, mortality rate, feed conversion efficiency, specific gravity of eggs and yolk colour were not significantly affected by the level of sunflower seeds in the diet. Increasing the dietary level of lysine in a diet based on wheat and meat‐and‐bone meal increased (P&lt;0.05) egg weight, egg mass, and feed conversion efficiency. Supplemental lysine reduced (P&lt;0.05) the feed intake of hens given the diet with 40 g kg−1 of sunflower seeds. Egg quality characteristics were not affected by the dietary level of lysine.

Performance of White Leghorn Hens in Response to Cage Density and the Introduction of Cage Mates

Hens reared at densities of 344 and 516 cm2/bird produced significantly fewer hard-shelled (HS) and shell-less (SL) eggs than hens reared at a density of 1031 cm2/bird. Soft-shelled (SS) egg production was not affected by the density treatment. A decline in ovulation rate would account for the decrease in total hen-day production in response to the higher density treatments.To determine if the introduction of new cage mates would cause hens to lay fewer eggs with poorer shell quality, the performance of hens with visitors was compared with those with nonvisitors. Visitors were introduced monthly for 13 months. Visitors vs. nonvisitors showed no significant difference with regard to HS, SS, and SL egg production, feed efficiency, mortality, egg weight, and specific gravity.

Feed Restriction During the Growing Period, Forced Molt, and Egg Production

An experiment was conducted to examine postmolt laying performance of White Leghorn hens that had been subjected to feed restriction from 8 to 20 weeks of age.During the postmolt period, birds in all forced-molt (FM) groups consistently had higher percent hen-day egg production than the control birds. Within the FM groups, birds that had previously been restricted fed during the growing period at the rate of 70% of the control group's consumption (R70 -FM) consistently had higher percent hen-day egg production during most of the postmolt period than the nonrestricted fed birds (Ad lib.-FM). Significant (P<.05) improvements in albumen height and shell thickness were observed 4 weeks after the FM period. When premolt, molt, and postmolt periods were combined, R70-FM birds had the highest percent henday egg production and the best feed efficiency of any group.

The replacement value of triticale for barley in layer diets with or without rice pollard

AbstractIn a factorial experiment, the laying performance of White Leghorn hens given diets in which triticale replaced 100, 50 or 0% of barley either in the presence or absence of 210 g kg−1 rice pollard and with two levels (2.5 and 3.5 g kg−1) of methionine was examined. The replacement of barley with triticale had no significant effect on egg production, egg weight or feed conversion efficiency. The inclusion of 210 g kg−1 rice pollard increased the weight (P &lt; 0.01) and reduced the yolk colour (P&lt;0.01) of eggs. Neither triticale nor barley had a significant effect on liver weight and lipid content. Triticale increased the palmitoleic acid content but had no significant effect on the content of other fatty acids in the liver and yolk lipids. Rice pollard increased the concentration of linoleic and arachidonic acids in liver and yolk lipids while the concentrations of myristic, palmitoleic and oleic acids were decreased. Increasing the level of methionine from 2.5 to 3.5 g kg−1 in diets with either triticale or barley or rice pollard had no significant effect on any of the egg production characteristics.

Effect of Heat Stress and Diet Composition on Performance of White Leghorn Hens

A total of 192 Single Comb White Leghorn pullets were divided into three groups to study the effect of heat stress and diet composition on feed intake and laying performance at 21, 25, and 33 weeks of age. For each age group all birds were fed a control diet [17.1% crude protein (CP), 2770 kcal metabolizable energy (ME)/kg] for a 7-day period. During this time they were kept at a temperature of 18 C. The temperature was then immediately increased to 35 C, and groups of 16 birds offered either the control diet, a high protein diet (43.5% CP), a high energy diet (3371 kcal ME/kg), or a diet of high nutrient density (28.3% CP, 2842 kcal ME/kg, and 6.5% Ca) for a 3-day period. After the 3-day test period, temperature was returned to 18 C, although birds were still offered the experimental diets for an additional 4 days prior to returning to the control diet. Production parameters were measured for individual birds.Feed consumption, egg production (except for the 21-week-old birds), egg weight, and egg shell thickness decreased (P<.05) with heat stress. Increases in energy and calcium intake helped partially to maintain normal egg production, egg weight, and egg shell deformation. Egg weight and egg shell deformation returned to pretest levels within an 8-week postexperimental period. With the exception of those birds receiving the control and high nutrient density diets at 21 weeks of age, data collected over the test periods showed that heat stress caused a significant reduction (P<.05) in liveweight of birds.

Performance of Laying Hens Fed Various Phosphorus Levels Continuously or Phase Fed Decremental Phosphorus Levels

Two experiments were conducted to determine the influence of dietary phosphorus levels on performance of White Leghorn hens. In Experiment 1, dietary available phosphorus (AP) levels of .26, .36, .46, or .56% were fed continuously from 24 to 68 weeks of age. Concurrently, diets containing .46, .36, and .26% AP or .56, .46, and .36% AP were “phase fed” during the age intervals of 24 to 36, 36 to 48, and 48 to 68 weeks, respectively. Dietary AP levels of .16, .26, .36, and .46% were fed from 27 to 71 weeks in Experiment 2. Also, phosphorus was phase fed in this experiment at levels of .46, .36, and .26% AP or .36, .26, and .16% AP for ages 27 to 39, 39 to 51, and 51 to 71 weeks, respectively. No significant effects of dietary AP levels were observed in either experiment with respect to rate of egg production, feed efficiency, egg weight, eggshell thickness, changes in body weight, or mortality. In Experiment 1, rate of egg production, egg weight, and eggshell thickness of the hens fed .26% AP continuously were numerically less, and mortality was numerically greater, than those of hens fed higher AP levels. The percentage of ash and the quantities of phosphorus contained in carcasses (feather-free) at the end of Experiment 1 tended to be directly related to dietary AP level. Total carcass phosphorus of hens fed .26% AP continuously was reduced significantly as compared with all other treatment groups except for the hens fed .36% AP continuously. Neither concentration of carcass ash nor quantity of phosphorus in carcasses was affected consistently by dietary AP in Experiment 2.Assuming an average daily feed consumption of 95 to 100 g/hen, the results indicated that phase-feeding of dietary AP levels of .46, .36, and .26% and possibly .36, .26, and .16% during the age intervals of approximately 24 to 39, 39 to 51, and 51 to 71 weeks, respectively, will support high rates of egg production without excessive depletion of body phosphorus.

Dietary Energy Concentration Effect on Performance of White Leghorn Hens at Various Densities in Cages

White Leghorn hens housed at cage floor densities of 660, 440, or 330 cm2 each (2, 3, or 4 per cage) were fed diets with 2,737, 3,003, or 3,322 kcal/kg of metabolizable energy from 21 to 73 weeks of age.As density of hens per cage increased, hen-day egg production and efficiency of feed utilization were reduced, whereas mortality increased. Final body weight decreased most with 4 hens per cage. Feed intake, energy intake, and egg quality characteristics were little affected.Dietary energy level did not significantly affect overall hen-day egg production. However, the highest dietary energy consistently resulted in the lowest egg production during the latter part of the experiment. This decrease was most noticeable with hens housed 4 per cage. This confirms our earlier conclusion with heavy, egg-type hens that high dietary energy is not conducive to sustained egg production with high density housing of hens in cages.Increasing the dietary energy level decreased feed intake and consequently increased efficiency of feed utilization. However, energy intake/hen was similar with all diets. Total mortality as well as that caused just by traumatic events increased as dietary energy increased. Egg quality characteristics were little affected by dietary energy.In agreement with our earlier study with heavy, egg-type hens, we conclude that increasing dietary energy level for White Leghorn hens will not reverse the downward trend in egg production that occurs as hen density in cages increases. The only depressive effect of increasing hen density in cages that was partly reversible by increasing dietary energy was the decline in body weight.

Effects of Intermittent Watering on the Performance of White Leghorn Hens

Three experiments were designed and conducted to study the effects of intermittent watering on the performance of laying hens. A total of nine intermittent watering treatments were evaluated in the experiments. Providing water on an intermittent basis had no statistically significant effect on hen-housed egg production, hen-day egg production, egg weight, feed per dozen eggs, egg specific gravity or average body weight. In experiment 3, the hens receiving water ad lib. had significantly (P<.05) lower mortality than hens on the intermittent watering treatments. The egg production curves do not indicate that intermittent watering during times of high temperature and peak egg production had any detrimental effects on egg production.

The Effect of Dose Rate upon Reproductive Performance of White Leghorn Hens and Their Progeny

Groups of 30 White Leghorn hens were exposed to 800 R (60 Co) at each of the following dose rates: 1, 5, 25, or 42 R/min. and compared with 30 hens kept as controls. Reproductive performance was recorded in these hens and their progeny from eggs hatched at varying times after irradiation. Half the surviving hens in each group were exposed to 800 R (25 R/min) 159 days after the first irradiation and egg production recorded for 8 weeks. Egg production was reduced by dose rates varying from 5-42 R/min during the first 5-6 weeks after irradiation. Hatchability of the eggs was reduced during the first 14 days after irradiation at 25 and 42 R/min, but the reproductive performance of the progeny was not altered. The 42 R/min rate given in the first irradiation seemed to have a residual effect on egg production over an 8-week period after the second exposure of 800 R at 25 R/min.

Effects of DDT and Charcoal on Performance of White Leghorn Hens ,

White Leghorn hens were fed diets containing DDT (0 or 300 p.p.m.) and activated charcoal (0 or 3%) in factorial arrangement for a 30 day period to study the effects on hen performance, egg quality, embryo and progeny growth. The presence of charcoal in the diet reduced the DDT deposition in the hens’ abdominal fat and in the egg yolk. Charcoal also reduced yolk pigmentation. Neither DDT nor charcoal affected the egg weight or shell thickness. Embryo development from hens fed DDT and/or charcoal appeared normal. There were no differences in hatchability, fertility, or progeny growth related to the treatments.

A marginal income and cost analysis of the effect of nutrient density on the performance of white leghorn hens in battery cages1

Synopsis In an experiment lasting 40 weeks with 576 caged White Leghorn (WL) hens and using linearly programmed least‐cost rations, the influence of increasing the nutrient density by increments of 100 kcal metabolisable energy (ME)/kg food, within the range 2500 to 3200 kcal ME/kg, on production was studied. Increasing the nutrient density was accompanied by increases in egg weight, body weight and ME intake/hen d but mortality and the number of eggs laid were not affected (P<0.01). From a regression analysis carried out on the combined results of this and of another similar experiment, it was found that with each 100 kcal/kg rise in the ME content, the mean ME intake/hen d increased by 3.14 ± 0.59 kcal, the body weight by 38.85 ± 10.7 g and the egg weight by 0.21 ± 0.04 g. A marginal income and cost analysis, using the above data, was carried out for three price situations of raw materials in 1970 and for two price situations of eggs and carcasses. The rations had a marginal cost structure for each nutr...

The influence of graded levels of atmospheric ammonia on chickens. II. Effects on the performance of laying hens.

Synopsis Studies have been carried out to ascertain the effects of ammonia on the performance of White Leghorn hens housed in various environments of defined temperature and humidity. At 18° C. and 67 per cent relative humidity, the use of atmospheres containing 105 p.p.m. of ammonia by volume, significantly reduced egg production after 10 weeks’ exposure. No effects were observed on egg quality. However voluntary food intake was reduced in ammoniated atmospheres and live‐weight gain was lower. No recovery in production occurred when the treated groups were maintained for a further 12 weeks in an atmosphere free of ammonia. When White Leghorn hens were housed at an environmental temperature of 28° C., body weight declined. The decrease in live‐weight was greatest at the high ammonia concentration of 102 p.p.m., and was significant after only 1 week's exposure to ammonia. Food intake of the controls was approximately 25 per cent lower at 28° C. than at 18° C., whilst 100 p.p.m. of ammonia further reduced food intake by more than 10 per cent. In one experiment at 28° C., egg production was significantly reduced after 7 weeks' exposure to ammonia. In a subsequent trial, a high protein, vitamin and mineral diet prevented the onset of any deleterious effects of ammonia on egg production, even though food consumption fell to 75 g./bird/day at 29° C., 43 per cent relative humidity and 104 p.p.m. of ammonia. When a diet low in energy level was fed to hens subjected to high concentrations of ammonia, their voluntary food intake did not increase, and their production deteriorated rapidly.