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At least 1,261 records · Page 70Linked to original sources
PubMed1999

Performance of laying pullets fed on cereal-free diets based on maize offal, cassava peel and reject cashew nut meal.

1. A 70-d experiment was conducted to determine the response of 26-week-old laying pullets to cereal-free diets based on maize offal, cassava peel and full-fat cashew nut meal (CNM) in comparison with a standard 550 g maize/kg reference diet. The 4 test diets all contained 315 g CNM/kg 232.5, 155.0, 77.5 and 0.0 g/kg of maize offal in combination with 77.5, 155.0, 232.5 and 315.0 g/kg of cassava peel, respectively. 2. Pullets fed on the 4 CNM-based diets consumed (P<0.05) less food than those fed on the reference diet; they also had lower (P<0.05) rates of lay, produced less (P<0.05) egg mass, had lower (P<0.05) food conversion efficiencies and their eggs had a lighter (P<0.05) yolk colour. Pullets fed some of the CNM-based diets also gained more (P<0.05) weight, the heaviest (P<0.05) being birds reared on the diet containing 315 g/kg cassava peel. Egg weight, shell thickness and albumen height from all eggs were similar. Pullets fed on the CNM-based diets had inferior (P<0.05) retention of dry matter and protein. 4. It was concluded that feeding full-fat CNM allowed for high dietary inclusion rates of cassava peel and maize offal and the resultant diets, which contained no maize, supported satisfactory performance of laying hens.

Animal Feed↗
PubMed1979

Shell thinning and residues of organochlorines and mercury in seabird eggs, Eastern Canada, 1970-76.

Organochlorine and mercury concentrations are reported for 252 eggs of Leach's storm-petrel (Oceanodroma leucorhoa), double-crested cormorant (Phalarocorax auritus), common eider (Somateria mollissima), common tern (Sterna hirundo), razorbill (Alca torda), common murre (Uria aalge) black guillemot (Cepphus grylle), and Atlantic puffin (Fratercula arctica) from the Bay of Fundy, the Gulf of St. Lawrence, and the open Atlantic shore of Canada during 1970-76. Concentrations of all organochlorines except DDE and polychlorinated biphenyls (PCBs) were low. DDE, PCBs, and mercury residues were highest in cormorant and petrel, intermediated in alcids, and lowest in eider and tern. Temporal and spatial aspects of contamination patterns are discussed. Authors conclude that only in cormorants were DDE residues high enough to cause, through eggshell thinning, local population declines.

Animals↗
PubMed1976

Lead in tissues of mallard ducks dosed with two types of lead shot.

Mallard ducks (Anas platyrhynchos) were sacrificed one month after ingesting one number 4 all-lead shot or one number 4 lead-iron shot. Livers, kidneys, blood, wingbones, and eggs were analyzed for lead by atomic absorption. Necropsy of sacrificed ducks failed to reveal any of the tissue lesions usually associated with lead poisoning in waterfowl. Lead levels in ducks given all-lead shot averaged about twice those in ducks given lead-iron shot, reflecting the amount of lead in the two types of shot. Lead in the blood of ducks dosed with all-lead shot averaged 0.64 ppm, and 0.28 ppm in ducks given lead-iron shot. Lead residues in livers and kidneys of females given all-lead shot were significantly higher than in males. In both dosed groups, lead levels in wingbones of females were about 10 times those in males, and were significantly correlated with the number of eggs laid after dosage. Lead levels in contents and shells of eggs laid by hens dosed with all-lead shot were about twice those in eggs laid by hens dosed with lead-iron shot. Eggshells were found to best reflect levels of lead in the blood. Our results indicate that mallards maintained on a balanced diet and dosed with one lead shot may not accumulate extremely high lead levels in the liver and kidney. However, extremely high lead deposition may result in the bone of laying hens after ingesting sublethal amounts of lead shot as a result of mobilization of calcium from the bone during eggshell formation.

Animals↗
PubMed1986

Effect of high levels of monensin during the growing period on subsequent breeding performance of adult broiler breeders.

The breeding performance of broiler breeder chickens previously raised on high levels of monensin was evaluated. The birds were raised on concrete floors in an open-sided pullet brooding and growing house. At 21 weeks of age monensin feeding was stopped and birds were placed in the breeder house. A breeder ration formulated to contain 2,920 kcal metabolizable energy and 16% crude protein was fed to all the birds irrespective of the growing system used. A standard feeding allowance and lighting program as recommended by Indian River International was followed during the laying period. The parameters determined were body weight uniformity at 21 weeks of age, egg production, egg weight, shell weight, shell thickness, feed conversion (kilograms feed/dozen eggs), mortality, fertility, and hatchability. Assays for monensin residue in the breast muscle, liver, and abdominal fat were run at 52 weeks of age (31 weeks after monensin withdrawal). Birds grown on high levels of monensin were not as uniform in body weight at 21 weeks of age as the restricted controls. Only birds fed 400 ppm of monensin with a low protein diet during the growing period showed a significant reduction in egg production, shell weight, and shell thickness. There were no significant differences among the growing systems in mortality during lay, fertility, hatch of fertile eggs, and hatch of total eggs. Monensin was not detectable (less than .1 ppm) in the liver, abdominal fat, and breast muscle.(ABSTRACT TRUNCATED AT 250 WORDS)

Animal Feed↗
PubMed1995

Influence of dietary osteolathyrogens on the ultrastructure of shell and membranes of eggs from laying hens.

1. Laying hens were fed osteolathyrogens, either semicarbazide hydrochloride at 0.3 g/kg or beta-aminopropionitrile fumarate at 0.6 g/kg, to examine their effects upon the ultrastructure of shell and shell membranes by scanning electron microscopy. 2. Effects of the 2 lathyrogens were similar. Compared with the highly-branched network of fine fibres in normal membranes, there is widespread lack of separation of fibres in lathyritic specimens and hence, uneven distribution of nucleation sites. Pores are also uneven in size and distribution, which can account for increased permeability. 3. Establishment between shell and membranes is reduced. Within the cone layer both type A and type B mammillary bodies occur. Large interstitial spaces and late fusion of the palisade layer indicate reduced resistance to fracture.

Aminopropionitrile↗
PubMed2005

Effects of supplementing broiler breeder diets with organic selenium and polyunsaturated fatty acids on egg quality during storage.

We assessed the effects of supplementation of broiler breeder diets with polyunsaturated fatty acids (PUFA) and organic Se on hatching egg quality during storage. Broiler breeders (n = 352) were fed 1 of 4 diets: SO (soybean oil with no added Se), SO with Se (SO+Se), fish oil (FO), or FO and Se (FO+Se). Eggs from prepeak (23 wk) and peak production (27 wk) breeders were stored for 14 d under typical (15 degrees C, 78% RH) conditions. Eggs were analyzed for albumen Haugh units (HU) and pH, shell characteristics, egg component weight, Se content, and fatty acid (FA) profile. The efficiency of transfer of Se into the egg was greater in low Se treatments compared with in high Se treatments. The majority of Se from the low Se treatments was deposited in the yolk, whereas in high Se treatments, the Se was deposited evenly in the yolk and albumen. In the low Se treatments, the Se content of yolk and albumen was lower than in the high Se treatments and decreased as age increased. Albumen HU decreased with increased storage, although high Se treatments had greater HU compared with low Se treatments. Eggs from the FO treatment were smaller with thinner eggshells compared with the SO treatment, but addition of Se to the FO diets ameliorated some of these effects. The egg yolk FA profile from the SO+Se treatment was altered compared with that from the SO treatment, perhaps due to interactions between dietary PUFA and Se-dependent enzyme systems. Hatching egg quality during storage was affected by dietary PUFA and Se content, as well as broiler breeder age.

Animals↗
PubMed1987

Effect of a single injection of adrenaline on shell ultrastructure in a series of eggs from domestic hens.

1. Adrenaline (1 mg in 1 ml water) was administered subcutaneously to three hens to determine whether any changes in the shell ultrastructure of subsequent eggs would occur. 2. The egg shells were examined in a scanning electron microscope after plasma etching. 3. The first three eggs laid by each bird after adrenaline injection were compared with previously-collected normal eggs from the same birds and also with control eggs collected over the same period from three hens which had received no adrenaline. 4. The first egg laid following adrenaline treatment was essentially normal but both the second and third eggs showed severe structural disorganisation at all levels, from the mamillary caps up to the cuticular layer. 5. Eggs laid 20 d or more after adrenaline treatment had reverted to normal. 6. The findings suggest that the abnormal eggs laid after hens have been exposed to disturbance or stress are likely to be affected in not only their external appearance but also to be of poor structural quality.

Animals↗
PubMed1981

Oxygen permeability of the shell and membranes of chicken eggs during development.

Oxygen permeability (KO2) was measured through the shell and shell membranes of chicken eggs throughout incubation. Shell KO2 was constant at 1.90 x 10(-6) cm3 O2 STP . sec-1 . cm-2 . Torr-1. Outer shell membrane KO2 was constant at 1.78 x 10(-6) cm3 O2 STP . sec-1 . cm-2 . Torr-1. Inner membrane KO2 increased from 0.11 x 10(-6) cm3 O2 STP . sec-1 . cm-2. Torr-1 to 1.56 x 10(-6) cm3 O2 STP . sec-1 . cm-2 . Torr-1. Calculations of KO2 from oxygen uptake rates and air cell PO2's were in close agreement with direct measurement of KO2. Resistance to oxygen flux was partitioned at each level. The outer membrane added 6% to the resistance of the shell. The inner membrane initially accounted for 88% of the shell/membrane complex resistance, but fell to 12% of the resistance by the end of incubation. The hypothesis is discussed that the increased permeability of the inner membrane is related to the evaporation of water from the membrane surface. The possibility is rejected that the shell membranes may be potential sites for respiratory adaptation to incubation at altitude.

Adaptation, Physiological↗
PubMed2004

Three new species of Huffmanela Moravec, 1987 (Nematoda: Trichosomoididae) from the gills of marine fish off New Caledonia.

Three new species of Huffmanela, here described from eggs only, are reported from the gills of marine fish caught off Nouméa, New Caledonia. Eggs of Huffmanela branchialis n. sp., from Nemipterus furcosus (Nemipteridae), are 45-52 (mean 48) microm in length and 23-30 (mean 25) microm in width, with thin shells. Each egg is enclosed in a thin membrane forming a spindle-shaped envelope 53-85 (mean 63) microm in length. Eggs of H. filamentosa n. sp., from Gymnocranius grandoculis (Lethrinidae), are 48-53 (mean 50) microm in length and 25-30 (mean 27) microm in width, with thin shells. Each egg bears a few long (150 microm), thin filaments. Eggs of these two new species were compared to those of H. paronai Moravec & Garibaldi, 2000, which are redescribed. Eggs of H. ossicola n. sp. were found within the branchial arch bone of Bodianus loxozonus (Labridae) and also filled the spinal chord bone and other bones. This is the first species of Huffmanela reported from bone tissue. Eggs are large, 72-88 (mean 79) microm in length and 32-40 (mean 36) microm in width, with a very thick shell. Each egg is covered with numerous filaments enclosed in a thin envelope. Fresh eggs were unembryonated, but embryos were visible after incubation in seawater. The three new species can be distinguished from other species of Huffmanela by size and the nature of the egg covering. Egg morphology of and their location in the host suggest different life-cycles: those of the first two species (small eggs, thin shells, egg covering possibly favouring flotation) are released from the gill mucosa with the turnover of living tissues and immediately continue their life-cycle, but eggs of H. ossicola (large eggs, thick shell) are only available for the continuation of the life-cycle after the host's death.

Animals↗
PubMed2006

In ovo exposure quail assay for risk assessment of endocrine disrupting chemicals.

Although there are in vivo assays using various organisms for the risk assessment of chemicals with endocrine disrupting properties, effective experimental methods for avian species are still under debate. We have developed an in ovo exposure assay using Japanese quail eggs, aimed at assessing disrupting effects on avian reproductive development and function. Hybrid eggs from Brazilian Brown male and White Egg female quails, which can be genetically sexed by their plumage color after hatching, were prepared, and test materials dissolved in olive oil were injected into the air-chamber on day 10 of incubation. After sexual maturation of hatched chicks, we observed egg production by females and the egg quality and male-typical reproductive behavior, and then examined reproductive system morphology and serum steroid concentrations in both sexes. Treatment with a synthetic estrogen, diethylstilbestrol (DES, 0.5-50 ng/g egg), dose-dependently reduced the eggshell thickness and strength of eggs. A few females treated with 5 ng/g DES per egg produced soft-shelled/ unmarked eggs, and all laying females treated with 50 ng/g egg produced eggs completely lacking shells. DES also induced shortening of the left oviduct and abnormal development of the right oviduct in a dose-dependent manner, while testis weight was reduced symmetrically. In addition, 2,2',4',6'-tetrachlorobiphenyl-4-ol (10-1,000 ng/g egg), which previously showed relatively high estrogenic activity in vitro, caused dose-dependent shortening of the left oviduct and reduction in testis weight. The methods for evaluating endocrine disrupting effects and preparing experimental birds proposed in the present study are expected to facilitate assays for avian reproductive toxicology.

Animals↗
PubMed2005

Eggshell characteristics and penetration by Salmonella enterica serovar Enteritidis through the production period of a layer flock.

1. Egg weight, shell thickness, number of pores, cuticle deposition and ability of Salmonella enterica serovar Enteritidis (SE) to penetrate the shell were determined for eggs from one layer flock through the entire production period. 2. Penetration was assessed by filling the eggs with a selective medium that allowed visualising Salmonella growth on the inside of the shell and membrane complex. After inoculation of each shell with on average 2.59 log cfu, the eggs were stored for up to 20 d at 20 degrees C and 60% relative humidity (RH). 3. On average 38.7% of the eggshells became penetrated. Mostly penetration occurred on d 3. Although it affected all shell characteristics studied, hen age did not significantly influence eggshell penetration. 4. No correlations were observed between any of the shell characteristics studied and the ability of SE to penetrate the shell. The growth of SE on the shell is of major importance because shell contamination at 20 d of storage and SE penetration were highly correlated.

Aging↗
PubMed1975

Acid-base balance, plasma electrolytes and production performance of adult turkey hens under conditions of increasing ambient temperature.

Turkey hens were exposed to stepwise increases in ambient temperature from 21 degrees C. to 25 degrees C. to 30 degrees C. to 35 degrees C. at two-week intervals. Dietary calcium levels to 1.54, 2.01 and 2.48 percent were fed. Acid-base balance, plasma electrolytes and production performance were studied. The temperature increase caused a significant (P less than 0.05) decrease in plasma sodium, calcium, and magnesium, and in egg production, shell thickness and egg weight and a significant (P less than 0.05) increase in plasma potassium. There was no significant change in the acid-base balance of the blood as measured by blood PO2, PCO2 and pH. Egg production was not significantly correlated to blood gas activitelated to plasma calcium and magnesium levels. Dietary calcium levels had no influence on the parameters measured.

Acid-Base Equilibrium↗
PubMed1984

Relationship of dietary calcium level during the prelay phase of an induced molt to postmolt performance.

Leghorn laying hens were induced to molt by a combination of photoperiod reduction and fasting for 14 days, during which time the hens lost 31.5% of their initial body weight. The hens were then assigned to one of four diets containing 1.0, 1.75, 2.5, or 3.5% calcium until egg production resumed. The 3.5% calcium diet was fed to all treatments from the resumption of 5% egg production. Postmolt egg production and feed conversion were not affected significantly. Egg weight, shell weight, and egg specific gravity were not affected consistently. It was concluded that high dietary calcium levels immediately postfast have no adverse effect on postmolt performance.

Animals↗
PubMed1991

Effect of time of feeding on oviposition time and production parameters in broiler breeders.

In Experiment 1, four pens of 90 Ross dwarf broiler breeder hens and 9 cocks each were assigned to feeding times of 0830, 1130, and 1430 h. Eggs were collected hourly from 0800 to 1600 h, 5 days/wk for 4 wk. In Experiment 2, five pens of 30 Arbor Acres and 3 cocks each were assigned to feeding times of 0830, 1130, 1430, and 1730 h. Eggs were collected hourly from 0700 to 1600 for Days 6 through 10 of a 10-day treatment period. Feeding time did not significantly change oviposition time in dwarf broiler breeders, except for an increase in oviposition at 1600 h for hens fed at 1130 and 1430 h. Peak oviposition times were 1000 and 1100 h with distribution of ovipositions throughout the day. Egg weight, shell thickness, and egg production were not significantly affected by feeding time. In the standard-sized strain, afternoon feeding times significantly increased the proportion of afternoon ovipositions. The incidence of floor, dirty, cracked, and abnormal eggs was not significantly changed by feeding time in either experiment.

Analysis of Variance↗