SEARCH · Search PubMed

Results for “laying performance”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 253 records · Page 14Linked to original sources

PubMed1989

Response of White Leghorn hens to various dietary levels of Cassia obtusifolia and nutrient fortification as a means of alleviating depressed performance.

Two 28-day experiments with White Leghorn hens were conducted to determine the adverse effect level of ground Cassia obtusifolia seed (coffeeweed) in the diet and to examine the nutrient fortification required to improve depressed performance due to the presence of the seed. In both experiments, five individually caged hens were used for each of the four treatment replications. Treatments for Experiment 1 consisted of a control and six diets with ground C. obtusifolia seed substituted for a filler at levels of 2, 3, 4, 5, 6, and 7%. In Experiment 2, a series of nutritionally fortified (15 to 20% higher nutrient levels) and unfortified diets coupled with seed levels of 0, 4, 6, and 8% for a total of eight treatments was used. Average daily feed intake, hen-day egg production, egg weight, egg specific gravity, and body weight change were determined during each experiment. For Experiment 1, average daily feed consumption was measured every 24 h for the first 3 days. Egg production and feed consumption were significantly reduced by 2% seed in Experiment 1. Within the first 24 h, feed intake was decreased to 37% below that of controls by increasing to the highest seed level. Egg specific gravity dropped significantly below that of controls when hens were fed 5% seed. In Experiment 2, fortification improved feed consumption, hen-day egg production, body weight change, and egg specific gravity over that of birds fed unfortified diets with the same seed level. Finished diets contaminated with 2%, or more, C. obtusifolia seed can cause reduced performance in laying hens, but nutritionally fortifying these diets can help to alleviate depressed performance.

Animal Feed↗

PubMed1987

Effect of cage level (tier) on the performance of White Leghorn chickens.

Conflicting reports exist in the literature about the effects of cage level (tier) on laying hen performance. Results clearly indicate, under conditions of this study, that performance as measured by egg production, egg weight, and mortality significantly deteriorated in a linear fashion progressing from the bottom to the top in three and four tier cages. Causes may be related to fear associated with differences in light intensity or differences in exposure to visual stimuli between the tiers.

Animals↗

PubMed1990

Response of laying hens to asymmetrical interrupted lighting regimens: reproductive performance, body weight and carcase composition.

1. The performance of brown egg laying hens was compared under conventional and asymmetrical interrupted-lighting conditions. 2. Egg numbers and mean weight were similar under the two conditions, provided the apparent day perceived by the hen was the same under both lighting treatments. 3. Daily food intakes of intermittently-illuminated hens were not significantly lower than those of conventionally-lit birds. However, the reductions were of the magnitude reported in the literature and observed under commercial conditions. 4. Shell quality was unaffected by interrupted lighting in the period up to 60 weeks of age in two of the 4 genotypes studied. All breeds had lower shell weights under interrupted lighting in the last three months of lay. 5. Intermittently-lit hens had lower body weights, which approached significance, and significantly less carcase fat. There were no differences in ash, protein (N x 6.25) or water contents of the carcases, or in fat content at a given body weight. 6. There were no significant differences in the production responses of the 4-brown-egg hybrids to interrupted lighting. 7. Diets with differing concentrations of energy and protein were included in both trials, but there was no evidence of interaction between these nutritional treatments and the lighting treatments.

Animals↗

PubMedDate not supplied

Decreased egg production in commercial laying hens fed zearalenone- and deoxynivalenol-contaminated grain sorghum.

In an experiment to determine the effect of corn vs. grain sorghum on performance of laying hens, egg production decreased significantly in the grain sorghum-fed hens in each of two trials starting 24 weeks after the trials began. Necropsy of chickens fed both diets revealed buccal ulceration at the ventral aspect of the oral cavity and squamous metaplasia of the esophageal glands and submaxillary salivary glands. Lesions were much more severe in the sorghum-fed birds than in the corn-fed birds. Analysis of the grain sorghum and corn revealed the presence of mycotoxins. Zearalenone and deoxynivalenol were present in the grain sorghum, and a lower amount of deoxynivalenol and a trace of aflatoxin B1 were found in the corn. Although mycotoxin levels were low, interaction between these mycotoxins and others may have decreased egg production.

Animal Feed↗

PubMed2000

Lack of response of laying hens to relative humidity at high ambient temperature.

1. The effects of relative humidity (rh=40% to 70%) at high ambient temperature (Ta) on the performance of laying hens at different ages (8 to 10 months, Trial 1; and 16 to 18 months, Trial 2) was evaluated. Laying hens were exposed to 25 degrees C (control) for 3 weeks and thereafter acclimated for 1 week to 35 degrees C and 4 different rh. 2. Body weight declined significantly in young and older hens exposed to 60% or 70% and 70% rh, respectively: Food intake declined with increasing Ta, except in the case of older hens exposed to 60% rh, for which it remained relatively constant. Water consumption, however, increased with increasing Ta but the increase was significant in young hens exposed to 70% rh only. 3. Egg production was not affected by the changes in Ta. However, a decrease in egg production was observed in older hens exposed to 60% rh. 4. Egg weight (EW), shell weight (SW) and shell thickness (ST) were significantly reduced by exposure to elevated Ta, whereas % breakage significantly increased. In young hens, a response to rh was exhibited in ST which was significantly higher in hens exposed to the low rh (40% to 45%) than in those exposed to the highest rh (70% to 75%). 5. It can be concluded that Ta is the main environmental factor affecting young and older laying hens while the effect of rh is minor.

Age Factors↗

PubMed2004

Effects of supplemental vitamin E during the laying period on the reproductive performance of Taiwan native chickens.

1. One-day-old Taiwan Native Breeder female chicks were fed on maize/soybean growing diets without supplemental vitamin E from hatch to 17 weeks of age. After 17 weeks the birds (n = 300) were randomly assigned to 5 dietary treatments and fed on maize/soybean laying diets supplemented with 0, 40, 80, 120 and 160 mg/kg of vitamin E (dl-alpha-tocopherol acetate), respectively, until 46 weeks of age. The variates measured included: age at first egg, feed consumption (FC), feed efficiency (FE), egg production (EP), egg weight (EW), egg specific gravity (ESG), eggshell strength (ESS), fertility and hatchability. 2. The addition of 120mg/kg of vitamin E lowered the first EW (P<0.05); however, there was no significant difference in the age or body weight (BW) of pullets at first egg or mortality rate to 46 weeks of age among the treatments. FE and egg mass were improved (P<0.05) in pullets fed 80 mg/kg of supplemental vitamin E. A significant increase in EP was observed after peak EP in pullets given 80 mg/kg of supplemental vitamin E. However, this favourable effect decreased as supplemental vitamin E exceeded 80 mg/kg. 3. From 17 to 46 weeks of age, egg quality (ESG and ESS) decreased with age. However, there was no correlation between age and fertility or hatchability during the experimental period, suggesting that egg quality is more age-sensitive than reproductive performance for breeder pullets. 4. Compared with the control, fertility and hatchability of all eggs set for the treatment with 80 mg/kg supplemental vitamin E increased by 7.7 and 13.4%, respectively. There was no difference in the hatchability of fertile eggs. 5. These results suggest that using supplemental vitamin E during the laying period can improve the reproductive performance of breeder pullets. The addition of 80 mg/kg of vitamin E obtained the best performance in EP, egg mass, FE (feed/egg), hatchability and fertility.

Aging↗

PubMed2001

Effects of added dietary fat and phosphorus on the performance and egg quality of laying hens subjected to a constant high environmental temperature.

Two experiments were conducted to study the combined effect of nonphytate P (NPP), fat, and temperature on the performance and egg quality of hens pre- and postpeak. In Experiment 1, 192 Single Comb White Leghorn layers, aged 22 wk, were individually housed in cages under ambient (AT) and constant high temperature (CHT) of 33 +/- 1 C. In Experiment 2, 28-wk-old birds were used with a CHT of 35 +/- 1 C. Diets contained 0 and 4% added vegetable fat with four dietary NPP levels, ranging from 0.20 to 0.50% in Experiment 1 and from 0.15 to 0.45% in Experiment 2, at increments of 0.1%. These diets were fed to hens for 84 d. Performance and egg quality criteria were measured in both experiments, whereas serum and tibia Ca and P were determined in Experiment 2. Results showed that there was no significant interaction among NPP, fat, and temperature, for any criteria measured. The CHT significantly reduced BW, feed intake, egg production, egg weight, egg mass, and shell thickness. Moreover, it decreased (P < 0.05) serum Ca, P, tibia ash, and tibia P. The lowest NPP levels resulted in the greatest shell thickness (P < 0.05), which decreased with increasing NPP levels in both trials. In the postpeak experiment, the feed intake was significantly reduced by 0.15 and 0.25% NPP. Moreover, 0.15% NPP significantly reduced egg production as compared to 0.35 and 0.45% NPP diets. Levels between 0.25 and 0.45% significantly improved the serum phosphorus content as compared to 0.15%. Added fat improved only serum P level (P < 0.05). The beneficial effect of supplemental fat on hen performance was evident in Experiment 1 but not in Experiment 2, indicating that nutrients were oriented more toward supporting egg production rather than maintaining the BW at the postpeak stage.

Animal Feed↗

PubMed1984

Special calcium appetite in laying hens.

An experiment was conducted to study calcium appetite and dietary calcium level related to laying hen performance. The experiment consisted of three periods: pre-experimental, training, and experimental. A total of 80 commercial strain laying hens (58 weeks old) were divided into two groups. One group (20 birds) served as a control throughout the experiment and was fed 3.5% dietary calcium without a free-choice calcium supplement. The other 60 birds were randomly divided into 3 sets of 20 and were all fed 3.5% dietary calcium for a pre-experimental period (13 days) as an adaptation period to a new environment prior to a training period (5 weeks). Dietary calcium level was decreased by .5% each week through the 5th week (to 1% Ca) for all 60 hens during the training period. The birds were given access to a free-choice calcium supplement (calcium carbonate granules) during both the pre-experimental and training periods. This dietary regimen was used in an effort to allow all hens to adapt to a supplemental feeding program and be prepared or conditioned for sudden changes in dietary calcium level. At the end of the training period, the 3 sets of 20 hens were fed either 1, 3, or 5% dietary calcium and a free-choice calcium supplement for 6 weeks. As dietary calcium level was increased, there was a decrease in free-choice supplemental calcium intake; however, all birds (except controls) consumed very large amounts of calcium. The training procedure was successful: no hens rejected the supplement. Neither dietary calcium level nor total calcium intake affected feed intake.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed2005

Performance and nutrient utilization of laying hens fed low-phosphorus corn-soybean and wheat-soybean diets supplemented with microbial phytase.

Two experiments were conducted with laying hens (Lohmann Brown) in an individual cage system and with single feeding conditions. Experiment 1 (n = 24) was a performance trial (22 to 61 wk) to evaluate phytase effects on performance and nutrient utilization in corn-soybean meal (CSM1) and wheat-soybean meal (WSM1) basal diets (0.12% NPP; 3.1% Ca) supplemented (300 U/kg) with an experimental microbial phytase (CSM2 and WSM2) or 1.5 g/kg inorganic P (CSM3 and WSM3). Experiment 2 (n = 16) was also conducted as a performance trial (22 to 61 wk) only using CSM diets with dietary treatments similar to those in experiment 1. In addition, parallel N and P balance experiments in 2 age periods (26 and 33 wk, respectively) were conducted. In experiment 1, no significant (P < 0.05) differences in mortality, feed intake, egg production, egg weight, or body weight were observed. Tibia bone mineral composition was significantly affected by microbial phytase. Microbial phytase in the low-P CSM diet significantly (P < 0.05) improved the feed conversion ratio. In experiment 2, only feed conversion ratio was significantly improved by microbial phytase. The phytase supplementation had no significant effect on P excretion, P balance, P utilization, N balance, N utilization, or AMEn in the balance experiments.

6-Phytase↗

PubMed1976

Influence of Fusarium-infected corn and F-2 on laying hens.

Diets containing either Fusarium-infected corn supplying 25 and 100 p.p.m. of F-2 (zearalenone) or purified F-2 at these levels did not adversely influence the reproductive performance of laying hens. In trial 1, no deleterious effects were observed for 20- and 36-week body weights, age at first egg, egg weight, albumen height, shell deformation, fertility or hatchability when Fusarium-infected corn was fed to 20-week-old pullets for 28 days. Percent hen-day egg production of birds fed Fusarium-infected corn supplying 25 and 100 p.p.m. of F-2 was superior (P less than or equal to 0.5) to egg production of nontreated controls. In trial 2, three replications of ten adult Leghorn hens were evaluated under five dietary treatments: (1) 16.7% protein basal; (2) basal plus Fusarium-infected corn (25 p.p.m. of F-2); (3) basal plus 25 p.p.m. of (purified) F-2; (4) basal plus Fusarium-infected corn (100 p.p.m. of F-2); (5) basal plus 100 p.p.m. of (purified) F-2. Difference between dietary treatments for 14-day pre-treatment, treatment and post-treatment periods were nonsignificant for 42- and 44-week body weights, egg production, egg weights, fertility and hatchability. Body weights of chicks from hens fed F-2 diets were not significantly different from those of chicks from hens fed the basal diet.

Animals↗

PubMed1989

Effects of lighting program during the growing period and dietary fat during the laying period on broiler breeder performance.

In two experiments, broiler breeders were grown in either of two lighting regimens, fed diets without added fat, and then fed diets with or without 5% added poultry fat during the subsequent laying period. In Experiment 1 half the birds were subjected to decreasing daylength using daylight (800 lx) and half were subjected to 9 h of incandescent light (20 lx) to 20 wk of age. In Experiment 2 the lighting regimen was either an 8-h photoperiod supplied by daylight (800 lx) or an 8-h photoperiod supplied by incandescent light (20 lx) to 20 wk of age. Added dietary fat produced significantly higher egg weight (Experiments 1 and 2), egg production (Experiment 2), and significantly lower fertility and hatchability of fertile eggs (Experiments 1 and 2). Short photoperiods (8 or 9 h) provided by incandescent light produced significantly higher fertility (Experiments 1 and 2) and hatchability of fertile eggs (Experiment 2), and significantly lower egg specific gravity, shell percentage (Experiment 1), egg weight, and eggshell weight (Experiment 2). Effects on fertility may be related to higher female body weight during lay due to daylight rearing or added fat, or relative changes in light intensity at photostimulation.

Analysis of Variance↗

PubMed1977

The effect of Marek's disease vaccination and day-old debeaking on the performance of growing pullets and laying hens.

In a 2 X 2 completely randomized factorial design, four hundred day-old Single Comb White Leghorn pullets were randomly assigned to four treatment combinations of vaccinated, non-vaccinated, debeaked and non-debeaked groups. Vaccination and debeaking were performed at day-old by administering 2,000 P.F.U. of HVT vaccine/chick and by removing approximately 2/3 of the upper beak, respectively. All the data were analyzed at 5% level of probability. Vaccination reduced feed consumption significantly only during the early growing period of the first 12 weeks, whereas debeaking caused a significant reduction in feed consumption throughout the experimental period of 80 weeks. Mortality during the 20-week growing period was not affected by either vaccination or debeaking. During the laying period (20-80 weeks of age), vaccination reduced the mortality numerically, while debeaking reduced the mortality significantly. Final body weight, hen-day egg production, egg weight, albumen height and egg shell thickness were not influenced by either vaccination, debeaking or a combination of the two. Debeaking had no effect on the incidence of blood-spotting in the eggs. Vaccination, however, significantly reduced percent blood spots in the eggs. Day-old debeaking effectively prevented the occurrence of cannibalism.

Animals↗

PubMed2004

Single-rescuer cardiopulmonary resuscitation: 'two quick breaths'--an oxymoron.

The Guidelines 2000 for CPR and ECC recommend for single lay-rescuers performing basic life support, "two quick breaths followed by 15 chest compressions", repeated until professional help arrives. It is uncertain that this can actually be accomplished by the majority of lay rescuers. We evaluated 53 first-year medical students after completing BLS CPR training to determine if they could deliver the goal of 80 compressions per minute when following this AHA BLS recommendation. Alternatively, a simplified technique of uninterrupted chest compression (UCC) BLS CPR was also taught and compared with standard BLS CPR (STD). The mean number of chest compressions/minute delivered with AHA BLS CPR was only 43 +/- 1 immediately after initial training and 49 +/- 2 when tested 6 months later. Uninterrupted chest compression BLS resulted in 113 +/- 2 compressions/min delivered immediately after training and 91 +/- 4 six months later (STD versus UCC; P < 0.0001). The mean length of time needed to provide the two breaths during STD-CPR was 14 +/- 1 and 12 +/- 1s (immediately after first training and six months after training). For STD-CPR, the mean minute ventilation was poor immediately after initial training (3.3 +/- 0.3 l/min) and further declined (1.9 +/- 0.4 l/min) at 6 months (P = 0.003). For single rescuer basic cardiopulmonary resuscitation, motivated BLS CPR-trained medical students take nearly as long as previously reported for middle-aged lay individuals to deliver these "two quick breaths". The "Guidelines 2000" recommendation for "two quick breaths" is an oxymoron, as it averages more than 13s. New recommendations for single-rescuer CPR should be considered that emphasize uninterrupted chest compressions.

Adult↗

PubMed1988

Order on the possession, distribution, dispensing, and administration of the pharmaceutical specialty Mifegyne 200 mg. in tablet form, 28 December 1988.

This French Order has been made having regard to an Order of 22 November 1988 inserting Mifepristone (RU 486) in division II of Schedule A of the Poisons Schedules. The following are among the principal provisions. Division I sets out duties of the manufacturer and wholesale distributors of the pharmaceutical specialty Mifegyne 200 mg in tablet form (Sections 1-5). Under Section 2, pharmaceutical establishments manufacturing or distributing this specialty must keep it in locked cupboards or premises. Under Section 3, every purchase or transfer by a wholesale pharmaceutical establishment, even without charge, must be recorded in a special register, following the procedures indicated. Requirements as to reporting are laid down in Section 4. The register referred to in Section 3 must be retained for 10 years. Division II covers the purchase of the pharmaceutical specialty Mifegyne 200 mg, in tablet form, by establishments performing voluntary terminations of pregnancy, and the dispensing and administration of this specialty (Sections 6-16). Detailed provisions are laid down concerning the procedures to be followed in purchasing, dispensing, etc. the specialty. In particular, a special numbered booklet is to be kept, containing a series of vouchers. The procedures for completing such vouchers and the conditions for their retention are indicated. Under Section 13, pharmacists may supply the specialty only to physicians entitled to prescribe it (and with their names and signatures filed with the pharmacist) or to the person in charge of a department in which voluntary terminations of pregnancy are performed. Section 14 lays down that only physicians performing such terminations are authorized to prescribe and administer this specialty. It is laid down in Section 15 that the pharmacist is to undertake, in the presence of the director of the establishment, a monthly inspection of the cupboard within the department where the specialty is kept.

Abortion, Induced↗

PubMed1996

Effects of changes in photoperiod and feeding opportunity on the performance of two breeds of laying hen.

1. ISA Brown and Shaver 288 hens, fed ad libitum, were given a 5-h increase or a 2, 5 or 10-h decrease in photoperiod at 215 d of age. Hens of both breeds were also maintained on constant 10, 13 or 18 h photoperiods. Other groups had their photoperiod increased from 8 to 13 h, or were held on constant days but had their access to food limited to 8 h per day. 2. Both breeds on ad libitum feeding exhibited curvilinear rate of lay and egg output, and linear food intake, responses to photoperiod change. Shaver hens reduced their egg output and rate of lay to a greater extent than ISA Brown hens when photoperiod was decreased. 3. In both breeds the beneficial effect on egg production of the 5-h increase in photoperiod was less than the adverse effect of the 5-h decrease. 4. The influence of light change per se generally had a greater effect on performance than the influence of feeding opportunity, but significant effects of changing feeding opportunity were demonstrated. 5. The reduction in mean rate of lay and egg output following a reduction in photoperiod was partly caused by some birds ceasing lay, but all birds showed some decrease in both variates.

Analysis of Variance↗

PubMed2003

Screening for post-traumatic stress disorder among refugees in Stockholm.

UNLABELLED: A screening procedure (The Health Leaflet; HL) to assist social workers in finding subjects with possible post-traumatic stress disorder (PTSD) in recently resettled refugees is presented. It is compared with two established self-rating instruments, the Harvard Trauma Questionnaire (HTQ) and Impact of Event Scale-22 (IES-22), as well as structured clinical interview. AIM: To validate the screening interview and the rating scales in comparison to a clinical assessment for PTSD, and examine the feasibility of lay screening for PTSD. FINDINGS: The Health Screening Interview with a cut-off value of 10 points identified cases with fully developed PTSD with both sensitivity and specificity about 0.7. Only two items--difficulties concentrating and having been exposed to torture--contributed to the discriminatory performance of the HL interview. In the HTQ symptom subscale, emotional detachment and a feeling of going mad contributed to the discriminatory performance. In the IES-22, recurring strong affects about the events, as well as intrusive memories, were the items with the highest canonical correlation coefficients. In the HL, the single screening question about difficulties concentrating identified 31/32 individuals diagnosed with PTSD in this group, with a relative risk of 24. CONCLUSIONS: A mental health screening procedure during refugee reception performed by lay persons is clearly feasible and can assist in identifying subjects with trauma-related healthcare needs, thus leading to more realistic demands in refugee reception.

Adolescent↗

PubMed2000

The effects of dietary available phosphorus levels and phytase on performance of young and older laying hens.

In the first of two experiments (20 to 70 wk of age), eight treatments consisted of corn-soybean meal diets (0.34% total P, 3.8% Ca, 17% CP, 2,758 kcal ME/kg) containing 0.10, 0.15, 0.20, 0.25, or 0.45% available P (AP), with the three lowest AP diets supplemented with 300 units of phytase/kg of diet. A second experiment evaluated the effect of feeding the 0.10% AP diet with and without phytase on performance and time required for onset of P deficiency in older hens (70 to 76 wk of age). In Experiment 1, the 0.10% AP diet with no supplemental phytase depressed performance by 28 wk of age. No other significant differences in performance were observed among treatments for the entire 20- to 70-wk period except that the 0.15% AP diet with no phytase resulted in body weights and tibia ash that were lower (P < 0.05) than those of hens fed the 0.45% AP diet during the last 30 wk. The mean daily AP intake of hens fed the 0.10% AP, 0.15% AP, 0.45% AP, or 0.10% AP + phytase diets was 94,159, 499, or 108 mg, respectively. Excreta P concentration was decreased by approximately 50% in birds consuming 0.10% AP + 300 U/kg phytase compared with those consuming 0.45% AP. In the second experiment, P deficiency signs occurred within 3 wk of consuming the unsupplemented corn-soybean meal diet (0.10% AP) compared with 8 wk in Experiment 1. The results of this study indicate that phytase improves P utilization in corn-soybean meal diets for laying hens and that a corn-soybean meal diet containing 0.15% AP (159 mg AP/d) or containing 0.10% AP + 300 units of phytase/kg (108 mg AP/d) supported optimal egg production from 20 to 70 wk of age. Additionally, results suggested that older hens may exhibit P deficiency symptoms sooner than younger hens.

6-Phytase↗

PubMed2006

Effect of type and level of fish oil supplementation on yolk fat composition and n-3 fatty acids retention efficiency in laying hens.

1. Laying hen performance and yolk fat fatty acid (FA) concentrations were evaluated with respect to the inclusion in the diet of different sources and levels of marine fish oil (MFO). 2. Twelve diets were arranged factorially, with three sources (MFO1, MFO2_EPA, MFO3_DHA) and four levels of inclusion (15, 30, 45 and 60 g/kg) of MFO. 3. Type of diet had little effect on egg production traits, although laying rate and shell thickness slightly decreased at the highest level of MFO supplementation. 4. An increase in level of inclusion of MFO from 15 to 60 g/kg linearly increased concentrations of C20:5 n-3, C22:5 n-3, C22:6 n-3 and total n-3 FA in yolk fat, but greatly impaired their efficiencies of deposition (g retained/g ingested). 5. An interaction between type and dietary concentration of MFO was found, as the reduction in efficiency of retention of n-3 FA in egg fat with level of MFO was less when the proportion of n-3 in total FA decreased or when that of DHA in total n-3 FA increased. 6. MFO3_ DHA was more efficiently used for total n-3 FA yolk deposition than MFO2_EPA at a similar total n-3 FA intake. 7. Dietary inclusion of MFO reduced LC n-6 FA yolk fat content, which additionally decreased the ratio between total n-6 and total n-3 FA in egg fat. 8. Regression equations were calculated in order to predict efficiency of retention and n-3 FA concentration of yolk fat in the range of diets studied.

Animal Feed↗