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PubMed1992

Determination of pyrimethamine and sulphadimethoxine residues in eggs by high performance liquid chromatography.

1. Laying hens were given food containing per kg diet: 1 mg pyrimethamine, 10 mg sulphadimethoxine (SDM) or 1 mg pyrimethamine with 10 mg SDM, for 14 days. Residues in the eggs were determined by high performance liquid chromatography. 2. Pyrimethamine was mainly found in yolk. Its concentration was slightly higher when it was given with SDM. 3. The concentrations of SDM in eggs were not different when it was given alone or in combination with pyrimethamine. 4. After withdrawal, pyrimethamine residues decreased below the detection limit (0.02 mg/kg) in the yolk after 11 to 12 d and in the albumen after 2 to 3 d. SDM in yolk fell below the detection limit (0.01 mg/kg) on day 7, whereas in albumen it was not detectable after 2 to 3 d.

Animals↗
PubMed1977

Productive performance and liver lesions in two strains of laying hens receiving two rapeseed meals.

A comparative study was conducted to determine the effect of two varieties of rapeseed meal at 10 and 20% levels in the diet on the productive performance, organ weights and liver lesions of two commercial strains of laying hens. The double-low (Brassica napus 1788) rapeseed meal appeared to be superior to Span meal (Brassica campestris) at the 10% level in maintaining egg production, feed efficiency, thyroid weight and body weight gain. However at the 20% level the productive performance was decreased in all the hens except the thyroid weights in the double-low group. Mortality caused by haemorrhagic liver syndrome was significantly higher among birds fed rapeseed meals than in the controls and was higher in the Span-fed groups than in those receiving the double-low variety. The two strains of birds showed no difference in mortality due to haemorrhagic liver syndrome. It was suggested that the lower level of glucosinolates in the double-low variety was responsible for the superiority of this meal over the Span meal.

Animal Feed↗
PubMed1996

Influence of temperature during growth on responses of hens to high or low temperatures during lay.

1. Commercial pullets were grown at cool (10 degrees -20 degrees C) or hot (25 degrees -35 degrees C) temperatures to similar bodyweights at 18 weeks of age. Between 18 and 50 weeks the birds were either kept at the same temperatures as during growth or transferred to the alternate temperature. 2. Birds kept at the cool temperatures throughout life ate most food and gave the best production during lay. Minimum food intake and poorest performance were obtained with birds kept at the hot temperatures throughout life. 3. Performance in the hot environment during lay was improved by rearing birds in the cool environment, the response being related to an increased food intake. Food intake in the cool environment during lay was reduced, with only minor effects on performance, in birds which had been reared in the hot environment. 4. The results of the present study show that production responses during lay are affected by the temperatures experienced by hens during both growth and lay.

Animal Feed↗
PubMed2003

To blow or not to blow: a randomised controlled trial of compression-only and standard telephone CPR instructions in simulated cardiac arrest.

This randomised controlled trial used a manikin model of cardiac arrest to compare skill performance in untrained lay persons randomised to receive either compression-only telephone CPR (Compression-only tel., n=29) or standard telephone CPR instructions (Standard tel., n=30). Performance was evaluated during standardised 10 min cardiac arrest simulations using a video recording and data from a laptop computer connected to the training manikin. A number of subjects in both groups did not open the airway. More than 75% in the Standard tel. group failed to deliver two effective initial rescue breaths, and only 17% provided an adequate inflation volume for subsequent breaths, delivering a median of only five inflations during the entire scenario. Most subjects in both groups gave chest compressions that were too shallow and at an inappropriately rapid rate. Hand position was also poor, but was worse in the group given simplified instructions. There was a significant delay to first compression in both groups, although this interval was shortened by over a minute when ventilations were eliminated from the telephone instruction algorithm (245 vs. 184 s, P<0.001). Over two-and-a-half times as many chest compressions were delivered during an average ambulance response time with compression-only telephone directions compared with standard CPR (461 vs. 186, P<0.001). These variables may be critical in predicting survival from out-of-hospital cardiac arrest. Further research is necessary to establish if modifications to scripted telephone instructions can remedy the identified performance deficiencies. Eliminating instructions for rescue breaths from scripted telephone directions will have little impact on the ventilation of most patients. Research is required to determine if the consequent reduction in the delay to starting chest compressions and the significant increase in the number of compressions delivered can increase survival from out-of-hospital cardiac arrest.

Adult↗
PubMed1999

["Topless" cardiopulmonary resuscitation? Should heart-lung resuscitation be preformed without artificial resuscitation?].

A paper published in various US journals on Emergency Medicine in 1997, has raised considerable concerns. The authors question if it is justified to continue to recommend initial ventilation as part of basic CPR when performed by lay-bystanders. A few aspects need to be discussed and some questions have to be answered before any changes in the current recommendations may even be considered: e.g. 1. How convincing does the available evidence support the following hypotheses: 1.1. Lay CPR without mouth-to-mouth-ventilation provides better outcome after cardiac arrest than lay CPR with mouth-to-mouth-ventilation. 1.2. Endotracheal intubation may be detrimental in patients suffering from hemodynamic compromises, particularly from VF. 2. Is it scientifically and ethically acceptable to design and perform prospective randomized controlled trials (RCTs) to evaluate the efficacy of those components of BCLS and ACLS which have in accordance with AHA-, ERC Guidelines and ILCOR Statements in the past been applied in millions of cardiac arrest victims and have obviously enabled the patients to lead a meaningful life after survival; under conditions of the proposed study design patients of the study group would be left without the treatment option ventilation, thus diminishing their chances of survival. Ad 1: The arguments presented by the authors are hardly convincing. The authors themselves state elsewhere that reluctance to perform mouth-to-mouth-ventilation should not represent a major problem because most cardiac arrests of cardiac etiology occur at home and in the presence of a relative or friend. Moreover, unreliable recommendations for mouth-to-mouth-ventilation (AHA), lack of training, retention of skills and knowledge, and a deficit in motivation include the main causes of the disappointingly low figures of bystander CPR worldwide. This situation cannot be improved simply by eliminating a lifesaving component of CPR-ventilation. Instead, the proposal to abandon the administration of unreasonably high ventilation volumes (800-1200 ml/breath) from the present guidelines and to recommend volumes ranging from 400-500 ml/breath recently made by the ERC should be given serious consideration. Furthermore, equipment and training manikins need to be adapted to these more reasonable volumes. Independently of the mechanisms of slow decreases in SaO2 after cardiac arrest (provided no compressions are performed) independently of gasping, ventilatory effects of standard compression or ACD-HCPR in the absence of mouth-to-mouth-ventilation, it is essential to realise that the patient's airways need to be maintained open at all times (this is unlike animal experiments where the airways are primarily kept open by the respective tissue structures): The minimum requirement of First Responder CPR is the guarantee that open airways are maintained. It may possibly be discussed if the present sequence of ABC might be changed to CAB, a practice adopted in the Netherlands many years ago, however, outcome trials an CAB have not been published to date. In addition, greater demands should be made of training requirements in BLS, attendance of refresher courses should be required, and other groups of the population should be included into these programmes than only relatives or friends of patients at risk of a cardiac arrest. The programmes need to be made mandatory for greater variety of groups and individuals to increase the efficacy and efficiency of bystander resuscitation. The hypotheses made by the above-mentioned authors are neither scientifically nor ethically acceptable. Ad 2: Pepe's argument regarding the efficacy of endotracheal intubation (ETI) in VF-patients has not been scientifically proven and lacks conclusive evidence. ETI serves to protect the airways and lungs against aspiration of regurgitated material and to facilitate artificial ventilation including PEEP, both under anaesthesia and resuscitation. The efficacy of ETI in the OR has long b

Cardiopulmonary Resuscitation↗
PubMed1991

Effects of food and mates on time budget in Aplysia fasciata: integration of feeding, reproduction, and locomotion.

This study examines the time budgeted to different behaviors in Aplysia fasciata under three conditions: (1) animals have constant access to food and mates: (2) there is access to food, but not to mates; (3) neither food nor mates are present. The data suggest a number of rules underlying behavioral integration: (1) Feeding, reproductive behaviors, and activity seem to be natural categories for behavioral choice. Feeding and reproductive behaviors are controlled in tandem by a common arousal mechanism, while time left over after animals feed and reproduce is distributed in a fixed ratio between locomotion (crawling and swimming) and inactivity (immobility and movement in place). (2) Relative distribution between different forms of locomotion and inactivity is modified by changes in motivational state. More time is spent swimming than crawling when feeding and/or mating is prevented, while more time is spent moving in place than immobile when the arousal level is increased. (3) Feedback control of feeding and reproduction is asymmetric. Satiation of feeding inhibits the common arousal. In the absence of food, time spent on reproductive behaviors increases due to disinhibition of the common arousal. By contrast, positive feedback arising from sexual behavior excites the common arousal. When mating is prevented by removing potential mates, time spent feeding decreases. (4) Generally, animals choose between performing the three main categories of behavior. Although Aplysia simultaneously can feed and mate, or locomote and mate, they do so infrequently. By contrast, different types of reproductive behaviors (male mating, female mating, egg-laying) are commonly performed simultaneously.

Animals↗
PubMed1982

The effect of reverse protein and low protein feeding regimens in the rearing period on pullet growth, subsequent performance, and liver and abdominal fat at end of lay.

Four brown egg strains were used to study the effect of rearing diets on growth and performance. The treatments were arranged in a 4 x 3 factorial with two replicates of 45 birds. The control diet was formulated and fed to National Research Council recommendations. Birds on reverse protein (RP) were fed diets with 13, 16, and 19% protein and those on low protein (LP) regimen received a 13.5% protein diet with amino acids adjusted on a megacalorie basis to approximate the control diet. At 20 weeks of age pullets were caged and fed a standard layer diet. Logistic curves were fitted to the growth data by a nonlinear least squares method and the parameters of each curve analyzed. No significant strain x diet interactions were observed. There were significant differences among strains in weight gain and feed intake. Dietary regimens had no significant effect on total gain and feed intake. However, diets significantly altered age at one-half maximum growth or inflection point (alpha) and mean growth rate (rho). Inflection point of the growth curve was significantly delayed in birds fed RP and LP diets. Although apparent conversion was not affected by diets, the partition coefficients at any time (t) for maintenance (beta mt) and gain (beta gt) were altered. Neither strain nor dietary regimens affected abdominal fat or organ weights at the end of the rearing period. No significant effect of rearing dietary regimens was detected in age at 50% production or peak production, feed conversion, feed intake, livability, liver fat, abdominal fat, or shell strength. The reverse-protein regimen significantly depressed egg weight. The results of the study indicate that 1) the rearing dietary regimens were adequate for strains of different body weight and egg output characteristics; 2) dietary alteration of growth curve parameters failed to influence production, feed intake, mortality, shell strength, livability, liver fat, or abdominal fat during the production period.

Abdomen↗
PubMed2001

Performance of broilers and production and egg quality parameters of laying hens fed 60% raw or treated common vetch (Vicia sativa) seeds.

Two experiments were conducted to study the effect of feeding 60% untreated (U) or coarsely ground treated vetch (V) seeds on performance of broilers and laying hens. In Experiment 1, the V seeds were soaked in 1% NaHCO3 (1:10) or in 1% acetic acid (1:5) at room temperature for 24 h (RTAA). Birds on the NaHCO3-treated V diet had 100% mortality rate but had significantly longer survival time than those on UV (14.9 vs 5.1 d). Birds on RTAA-V survived and had similar BW and feed conversion but greater kidney size than those of the controls at 7 wk of age (P < 0.05). In Experiment 2, control, UV, V soaked in water at 40 C (40WV), RTAA-V, and V soaked in acetic acid at 40 C (40AAV) diets were fed to laying hens for 84 d. The ground seeds in RTAA-V and 40AAV were soaked in acetic acid (1:10) at room temperature or at 40 C, respectively, for 24 h. For 40WV, the seeds were soaked in water (1:10) at 40 C for 72 h with a water change every 12 h. The UV-fed hens ceased egg production within 14 d and had the highest BW loss and the lowest feed intake among all treatments (P < 0.05). The 40WV and 40AAV significantly improved these criteria. Moreover, the RTAA-V resulted in performance comparable to that of the controls. Eggs produced by hens on treated V diets had similar weight but higher Haugh unit score (11 points), thinner shell, and lower yolk color score than those of the controls (P < 0.05). Results indicated that RTAA-V at 60% dietary level was not detrimental to broilers and laying hens.

Acetic Acid↗
PubMed1991

Temperature-dependent peptidergic feedback: potential role in seasonal egg laying in Aplysia.

alpha-Bag cell peptide (alpha-BCP), one of the secretory products of the neuroendocrine bag cells in Aplysia, has been reported by various investigators to have either excitatory or inhibitory feedback effects. Though conflicting, these results may be explained by the difference in temperature at which the experiments were performed. Because egg laying in this animal is temperature dependent, the alteration in function of this peptide by temperature may offer a possible molecular basis for the seasonal regulation of egg laying. This hypothesis was investigated by assessing the feedback actions of alpha-BCP at various temperatures. At 15 degrees C, alpha-BCP hyperpolarized bag cells, shortened the duration of synaptically evoked bag cell discharges, and reduced the number of action potentials per discharge. However, at 20 degrees C, the peptide depolarized bag cells, lengthened discharges, and increased the number of action potentials per discharge. A temperature-dependent influence on bag cell cAMP levels may underlie these effects, because alpha-BCP reduced basal cAMP levels in intact bag cells at temperatures of 15 degrees C and below, while at 17-22 degrees C it increased these levels. However, the inhibitory effects of alpha-BCP on stimulated adenylate cyclase activity in bag cell homogenates were not temperature dependent. Moreover, a low-Ca2+/high-Mg2+ solution abolished alpha-BCP's ability to increase bag cell cAMP levels at 20 degrees C. This suggests that the peptide may evoke the secretion of an excitatory modulator at the higher temperature. These results imply that alpha-BCP is autoinhibitory at typical winter temperatures, but becomes autoexcitatory as ocean temperature rises in the summer. Thus, the peptide may function in coordination with other factors to regulate egg laying in response to seasonal temperature variations.

1-Methyl-3-isobutylxanthine↗
PubMed2001

Effects of vitamin E and C supplementation on performance, in vitro lymphocyte proliferation, and antioxidant status of laying hens during heat stress.

Vitamin E (dl-alpha-tocopheryl acetate) was evaluated for its effects on performance, lymphocyte proliferation, and antioxidation in layers during heat stress. In Trial 1, 25, 45, or 65 IU of vitamin E/kg were fed to four replicated pens (five hens/cage) of DeKalb Delta or Hy-Line W-36 per treatment starting at 20 wk of age. At 34 wk of age, hens were heat-stressed at diurnal temperature ranging from 21 C to 35 C for 3 wk. The performances of hens not exposed to heat stress were not influenced by supplemental vitamin E. Supplemental vitamin E did not affect egg production; however, egg mass was greater (P < 0.05) with supplementation of 65 IU of vitamin E/ kg during heat stress. Egg yolk was significantly increased (P < 0.04) when hens were fed 45 and 65 lU/kg compared with the control vitamin E level (25 lU/kg). Haugh units were higher (P < 0.01) for hens fed 65 IU of vitamin E/kg compared to 25 and 45 lU/kg. Lymphocyte proliferative responses to concanavalin A (Con A) and Salmonella typhimurium lipopolysaccharide (LPS) were greater (P < 0.0001) in hens fed 45 and 65 IU of vitamin E/kg during heat stress. Strain had no effect on any of the parameters measured. In Trial 2, a 2 x 2 factorial was designed to test effects of vitamin C in drinking water (0 and 1,000 ppm) and dietary vitamin E (25 and 65 IU/kg). Eight replications per treatment with four hens per replication cage were heat-stressed at constant temperature of 35 C for 3 wk. Egg production and egg mass were higher when hens were fed 65 IU of vitamin E/kg than when hens were fed 25 lU/kg (81.5 vs. 75.9%, P < 0.03 and 48.2 vs. 44.6 g, P < 0.03, respectively). Yolk solids weight for the 65 IU vitamin E/kg group was higher (P < 0.01) compared to the 25 IU/kg group. ConA and LPS mitogenic responses were greater in hens fed 65 IU of vitamin E (P < 0.001 or P < 0.003, respectively) or 1,000 ppm of vitamin C (P < 0.001 or P < 0.002, respectively). The combination of 65 IU vitamin E/kg and 1,000 ppm vitamin C showed the highest ConA and LPS mitogenic responses among the treatments. No interaction effects of the two vitamins on production measurements or lymphocyte proliferative responses were observed. TBA values in egg yolk and plasma of hens fed 65 IU of vitamin E/kg were lower (P < 0.0001) than those of hens that received 25 IU of vitamin E/kg. These results suggest that vitamin E supplementation at 65 IU/kg diet may enhance production, induction of in vitro lymphocyte proliferation by ConA and LPS, and antioxidant properties of egg yolks and plasma of White Leghorn hens during heat stress and that supplementation of 1,000 ppm vitamin C may further enhance in vitro lymphocyte proliferative responses of hens during heat stress.

Animals↗
PubMed2003

Effects of phytase supplementation on the performance, egg quality, and phosphorous excretion of laying hens fed different levels of dietary calcium and nonphytate phosphorous.

An experiment employing a factorial arrangement of two levels (3.0 and 4.0%) of Ca, two levels (0.15 and 0.25%) of nonphytate phosphorus (NPP), and two levels (0 and 300 U/kg diet) of microbial phytase was carried out with 960 ISA-brown layers from 21 to 41 wk of age. There was a significant interaction between NPP level and phytase for egg production. High NPP level and phytase supplementation increased egg production only in the second 10-wk period (31 to 41 wk). High NPP and low Ca increased feed intake, and a significant interaction between levels of NPP and Ca was observed in the first 10 wk. High NPP improved feed efficiency only in the second 10-wk period. Low NPP improved egg specific gravity and eggshell thickness but decreased Haugh units in the first 10-wk period; high NPP decreased the percentage of broken and soft-shell eggs in the second period. Low Ca decreased egg specific gravity, eggshell strength, and eggshell thickness in both periods and increased Haugh units in the second 10-wk period. Phytase supplementation decreased the percentage of broken and soft-shell eggs. High NPP increased fiber availability but decreased Ca availability. High Ca decreased Ca availability, whereas phytase increased availability of dry matter, fiber, and P. High NPP increased retention of P and Fe but also increased excretion of P. High Ca decreased retention of Zn and Fe. Phytase supplementation increased P retention, resulting in decrease of P excretion. In conclusion, supplementation of microbial phytase at a level of 300 U per kg diet of laying hens can improve egg production, decrease broken and soft egg production rate, and P excretion. The effects of phytase supplementation are significantly modified by the level of Ca and NPP.

6-Phytase↗
PubMed1992

Zinc methionine for stressed laying hens.

The effects of zinc methionine product (ZP) supplementation to Single Comb White Leghorn hens on egg production and quality were measured through three consecutive egg laying cycles. During the first and second lay cycles, ZP had minor or nonsignificant effects upon hen performance. During the third lay cycle, a low dietary Ca (.3% Ca) stress of 1 mo duration was encountered. During this low-Ca stress period, hens fed 1 g ZP/kg produced the greatest number of eggs (P less than .05), and during recovery from that low-Ca stress, the hens receiving 2 g ZP/kg produced the most eggs (P less than .05). The ZP appeared to help hens maintain egg size throughout this stress period. The present results indicate that ZP was beneficial to hens during low-Ca stress and during the recovery period following that stress.

Animals↗
PubMed2004

[Optimization of the separation conditions of fingerprint for Rhubarb by high performance liquid chromatography].

OBJECTIVE: To optimize the separation conditions of fingerprint for Rhubarb by high performance liquid chromatography and lay the foundation of studies on its fingerprint by high performance liquid chromatography. METHODS: The reversed-phase high performance liquid chromatographic method was adopted. The samples were extracted by ultrasound and separated by a linear gradient elution on Shim-pack CLC-ODS column (6.0 mm i.d. x 150 mm, 5 microm), and then, with the methanol-1 ml/L phosphoric acid solution as mobile phase, were detected at UV 254 nm and column temperature 40 degrees C. During the linear gradient elution program, the volume fraction of methanol in mobile phase changed as follows: 0 min-5 min, 20%; 5 min-25 min, from 20% to 50%; 25 min-35 min, from 50% to 80%; 35 min-60 min, from 80% to 90%; 60 min-70 min, 90%. The flow rate was 0.8 ml/min from 0 min to 35 min, 0.6 ml/min from 35 min to 50 min and 1.0 ml/min after 50 min. RESULTS: The separation conditions described above achieved good result in the aspects of separable effect, stability, sensitivity, and reproducibility. CONCLUSION: The optimum separation conditions of fingerprint would be useful for establishing the method of fingerprint for Rhubarb by high performance liquid chromatography.

Chromatography, High Pressure Liquid↗
PubMed1984

Effect of dietary phosphorus level and source on productive performance and egg quality of two commercial strains of laying hens.

An experiment was conducted to study the influence of dietary total phosphorus (TP) level and source on the performance of two strains of commercial layers for two consecutive production years (26 to 68 and 76 to 116 weeks of age, respectively). Diet 1 contained .4% TP; Diets 2, 3 and 4 contained .5, .6, and .7% TP with supplemental P from dicalcium phosphate (DCP); Diets 5 and 6 contained .5 and .6% TP, respectively, with supplemental P from a sample of raw rock phosphate (RRP-1); Diets 7 and 8 contained .5 and .6% TP, respectively, with supplemental P from a second sample of raw rock phosphate (RRP-2). Calcium level was 2.75% in all diets, and crushed oyster shell provided ad libitum to all birds increased the total calcium to about 3.00%. Diet 1 was inferior to the average of all supplemented diets relative to feed consumption rate (P less than .005) and egg weight (P less than .005) during the first year. Diet 1 was also inferior relative to egg production rate (P less than .01), feed consumption rate (P less than .005), and egg weight (P less than .005) during the second year, whereas it was superior in shell quality (P less than .05) during the first year. Increasing TP from DCP resulted in a significant linear increase in feed consumption (P less than .05), feed conversion ratio, and Haugh units (P less than .005). Increasing TP from DCP also resulted in a significant linear decrease in shell quality (P less than .05) and significant linear and quadratic decreases in egg weight (P less than .005) during the first year. During the second year, increasing TP from DCP resulted in a significant linear decrease in egg production rate (P less than .005) and feed efficiency but significant linear (P less than .01) and quadratic (P less than .05) increases in feed consumption, and significant linear and quadratic increases (P less than .005) in Haugh units. Hens receiving RRP diets responded differently during the first and second years. The DCP supported greater egg weight than the RRP during the second year and permitted better feed conversion during both years. Strain A produced larger eggs than Strain B regardless of treatment (P less than .005). When egg production rate and most other response criteria were considered, .5% TP with DCP as the supplemental source gave the best results in both production years. A TP of .6% from RRP-2 gave similar results in both years.

Animals↗
PubMed1999

[Metabolic insights and nutrition of poultry].

Excessive specialization and high production requirements place high demands on the metabolism of poultry. A number of metabolic problems, such as disturbances of energy metabolism (affecting mainly hens) and mineral balance (affecting mainly laying hens), affect performance. Nearly all these problems are multifactorial in nature, but diet, and in particular the interaction between diet and phenotype, plays an important role. The problem of ascites in broiler hens is discussed in relation to external and genetic causative factors. Genetic factors can be further subdivided into structural and functional causative factors. This distinction has important consequences. For example, sudden death syndrome can be distinguished as a separate entity. Fatty liver syndrome in laying hens, and gout and urolithiasis in chicks and hens are briefly discussed. Finally, some of the most important or most common skeletal problems affecting poultry, namely, tibial dyschondroplasia, battery fatigue, rickets, and chondrodystrophy, are briefly discussed in the context of the dietary factors that underlie these disorders or which can be used as treatment.

Animal Nutritional Physiological Phenomena↗