THE IN VITRO UPTAKE OF TRITIATED OESTRADIOL BY THE OVIDUCT OF IMMATURE AND LAYING CHICKENS

1970 ◽  
Vol 63 (2) ◽  
pp. 265-274
Author(s):  
Helene C. Cecil ◽  
J. Bitman ◽  
C. S. Shaffner

ABSTRACT The oviduct of the immature chick had a special affinity for oestradiol during in vitro incubation with tritiated oestradiol. All anatomical portions of the oviduct concentrated 3-6 times more radioactivity than other body tissues. When the immature birds were pretreated with nonlabelled oestradiol, the ability of the ovary, liver and muscle to concentrate 3H-oestradiol was unaffected. In contrast, accumulation of radioactivity by oviducts from pretreated birds was reduced to a level comparable to other body tissues. The oviducts from nonlaying hens were able to accumulate more oestradiol per unit of weight than the oviducts from laying hens. Presumably the laying hen had a source of endogenous oestrogen which reduced the ability of the oviduct to accumulate 3H-oestradiol from the incubation mixture.

1982 ◽  
Vol 206 (3) ◽  
pp. 647-654 ◽  
Author(s):  
H Griffin ◽  
G Grant ◽  
M Perry

Very-low-density (VLD) lipoproteins and portomicrons were isolated from the plasma of immature and laying hens and their size, lipid composition and susceptibility to hydrolysis by lipoprotein lipase were compared. In agreement with other studies, VLD lipoproteins from laying hens were found to be smaller and have a different lipid composition than VLD lipoproteins from immature hens. Portomicrons from immature and laying hens had mean diameters of about 150 nm and similar lipid compositions. Hydrolysis of VLD lipoproteins from immature hens, and portomicrons from immature and laying hens, proceeded rapidly until at least 40% of the substrate had been used. In contrast only 1-15% of laying-hen VLD-lipoprotein triacylglycerol was readily hydrolysis occurred slowly. The limited susceptibility of laying-hen VLD lipoproteins appeared to be due to their low content of lipoprotein lipase activator apoprotein, which occurred despite an abundance of activator in the high-density lipoproteins of laying-hen plasma. The results provide further evidence that the liver of the laying hen synthesizes specialized lipoproteins. Their limited susceptibility to hydrolysis by lipoprotein lipase is probably a major factor in ensuring transport of lipid to yolk rather than to other tissues. The form of transport of dietary lipid, however, is similar in immature and laying hens.


1988 ◽  
Vol 27 (04) ◽  
pp. 151-153
Author(s):  
P. Thouvenot ◽  
F. Brunotte ◽  
J. Robert ◽  
L. J. Anghileri

In vitro uptake of 67Ga-citrate and 59Fe-citrate by DS sarcoma cells in the presence of tumor-bearing animal blood plasma showed a dramatic inhibition of both 67Ga and 59Fe uptakes: about ii/io of 67Ga and 1/5o of the 59Fe are taken up by the cells. Subcellular fractionation appears to indicate no specific binding to cell structures, and the difference of binding seems to be related to the transferrin chelation and transmembrane transport differences


1970 ◽  
Vol 64 (4) ◽  
pp. 687-695 ◽  
Author(s):  
Junzo Kato

ABSTRACT The anterior, middle, and posterior hypothalamus, the cortex cerebri, the anterior hypophysis as well as the diaphragm of adult ovariectomized rats were incubated in vitro with tritiated 17β-oestradiol. The uptake of tritiated oestradiol was differentially distributed intracerebrally with higher accumulation in the anterior hypothalamus and the hypophysis. Lowering the temperature of the incubation medium caused a reduction in the uptake of radioactivity by the anterior hypothalamus as compared to that found in other brain tissues. Tritiated oestradiol taken up in vitro by the anterior hypothalamus and the hypophysis tended to be retained after further incubation in a steroid-free medium. The addition of non-radioactive 17β-oestradiol to the medium inhibited the uptake of tritiated oestradiol by these tissues. Moreover, pretreatment with non-radioactive 17β-oestradiol in vivo prevented the preferential accumulation of tritiated oestradiol in vitro in the anterior hypothalamus and the hypophysis. These results indicate that oestradiol is preferentially taken up in vitro by the anterior hypothalamus and the hypophysis of the rat.


1960 ◽  
Vol XXXIV (II) ◽  
pp. 305-311 ◽  
Author(s):  
M. G. Woldring ◽  
A. Bakker ◽  
H. Doorenbos

ABSTRACT The red cell triiodothyronine uptake technique as used in our hospital is described. Incubation time is of almost no importance. The temperature during incubation should be 37° C. Further improvement of the technique is obtained when all blood samples are brought up to 40 % haematocrit prior to incubation. Clinical results are discussed. It is yet too early to give a definite assessment of its clinical value, but it is definitely superior to the measurement of the BMR.


Toxins ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 156
Author(s):  
Ling Zhao ◽  
Yue Feng ◽  
Jing-Tao Wei ◽  
Meng-Xiang Zhu ◽  
Lei Zhang ◽  
...  

The objective of this study was to evaluate the efficacy of mycotoxin binders in reducing the adverse effects of co-occurring dietary aflatoxin B1 (AFB1), deoxynivalenol (DON) and ochratoxin A (OTA) on laying hens. Three hundred and sixty 26-week-old Roman laying hens were randomly allocated into four experimental groups with 10 replicates of nine birds each. The four groups received either a basal diet (BD; Control), a BD supplemented with 0.15 mg/kg AFB1 + 1.5 mg/kg DON + 0.12 mg/kg OTA (Toxins), a BD + Toxins with Toxo-HP binder (Toxins + HP), or a BD + Toxins with TOXO XL binder (Toxins + XL) for 12 weeks. Compared to the control, dietary supplementation of mycotoxins decreased (P < 0.10) total feed intake, total egg weight, and egg-laying rate, but increased feed/egg ratio by 2.5–6.1% and mortality during various experimental periods. These alterations induced by mycotoxins were alleviated by supplementation with both TOXO HP and XL binders (P < 0.10). Furthermore, dietary mycotoxins reduced (P < 0.05) eggshell strength by 12.3% and caused an accumulation of 249 μg/kg of DON in eggs at week 12, while dietary supplementation with TOXO HP or XL mitigated DON-induced changes on eggshell strength and prevented accumulation of DON in eggs (P < 0.05). Moreover, dietary mycotoxins increased relative liver weight, but decreased spleen and proventriculus relative weights by 11.6–22.4% (P < 0.05). Mycotoxin exposure also increased alanine aminotransferase activity and reduced immunoglobulin (Ig) A, IgM, and IgG concentrations in serum by 9.2–26.1% (P < 0.05). Additionally, mycotoxin exposure induced histopathological damage and reduced villus height, villus height/crypt depth, and crypt depth in duodenum, jejunum and (or) ileum (P < 0.05). Notably, most of these histological changes were mitigated by supplementation with both TOXO HP and XL (P < 0.05). In conclusion, the present study demonstrated that the mycotoxin binders TOXO HP and XL can help to mitigate the combined effects of AFB1, DON, and OTA on laying hen performance, egg quality, and health.


Animals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 701
Author(s):  
Yi Wan ◽  
Ruiyu Ma ◽  
Anam Khalid ◽  
Lilong Chai ◽  
Renrong Qi ◽  
...  

One of the most important factors that determine feed utilization by chickens is the feed form. Although it is generally believed that pellet diets have a positive effect on chicken growth, there are some studies that have indicated no difference between pellet and mash on chickens performance. This study was conducted to assess the effects of feed form on production performance, egg quality, nutrient metabolism and intestinal morphology in two breed laying hens. Two hundred and sixteen 25-week-old Hy-Line brown (n = 108) and Hy-Line grey (n = 108) hens were selected. Each breed was randomly allocated into two treatments with 6 replications (9 birds in each replication), which were fed mash and pellet diets, respectively. Production performances were recorded daily and egg quality traits were measured every two weeks. At 42 weeks of age, one bird per replication from each experimental group was selected for metabolism determination and intestine morphology observation. Compared with mash diets, pellet diets improved laying rate (p < 0.05), ADFI (average daily feed intake, p < 0.05), egg weight, shell strength, yolk proportion and Haugh unit (p < 0.05) in both breeds and reduced the FCR (feed conversion ratio, p < 0.05) in Hy-Line grey. The apparent digestibility of DM% (dry matter) and CP% (crude protein) were significantly higher (p < 0.05) in both breed laying hens fed pellet than those fed mash. The apparent digestibility of P% (phosphorus) and Ca% (calcium) was higher in Hy-Line grey fed pellet and was higher in Hy-Line brown fed mash. Compared to mash diets, pellet diets increased the VH (villus height), CD (crypt depth) and VCR (ratio of villus height to crypt depth) of the small intestine of Hy-Line grey, and increased the VH and CD of duodenum and ileum of Hy-Line brown. Overall, pellet diets improved production performance and nutrition metabolism through positive changes in the laying rate, feed intake, egg albumen quality and apparent digestibility of laying hens. The current findings provided support for the advantages of feeding pellets during the peak egg laying period for the two popular laying hen strains, Hy-Line brown and Hy-Line grey.


1980 ◽  
Vol 2 (4) ◽  
pp. 281-283 ◽  
Author(s):  
R.A. Bulman ◽  
R.J. Griffin
Keyword(s):  

1968 ◽  
Vol 46 (8) ◽  
pp. 749-757 ◽  
Author(s):  
H. R. Raud ◽  
R. Hobkirk

The sulfurylation of estrone-6,7-3H, estradiol-17β-6,7-3H, and dehydroisoandrosterone-4-14C by laying hen liver, oviduct, and vaginal preparations was investigated. Purification and product identification included ether and ethyl acetate extraction, paper chromatography, and isotope dilution, before and after hydrolysis with a sulfatase preparation.The esterifying enzymes were found in the 105 000 × g supernatants of the three tissues. The liver preparation was many times more active in steroid sulfate synthesis than the corresponding oviduct or vaginal fractions. Sulfurylation of dehydroisoandrosterone displayed the same cofactor, pH, and temperature requirements as did that of estrone and estradiol-17β. The degree of dehydroisoandrosterone sulfate synthesis was considerably lower than that of the estrogens, however. It is suggested that the laying hen possesses an enzyme system which is more efficient for the sulfurylation of estrogens than of other steroids such as dehydroisoandrosterone.


2010 ◽  
Vol 79 (9) ◽  
pp. S29-S34 ◽  
Author(s):  
Miroslav Macháček ◽  
Vladimír Večerek ◽  
Nora Mas ◽  
Pavel Suchý ◽  
Eva Straková ◽  
...  

The aim of this study was to assess the effects of two levels of clinoptilolite administered in feed (2% and 4%) on some selected performance indicators, metabolic utilization of basic nutrients and the health status of laying hens. The selected 24 Bovans Goldline hybrid laying hens were divided into three equal groups, two experimental groups (E1 and E2) and one control group (C). The laying hens were housed individually in cages with an automatic supply of drinking water, manual feeding, in a setting with controlled light and temperature regimens. Hens from individual groups were all fed a complete feed mix of the same composition and the only difference was in clinoptilolite supplementation: feed mixes for E1 and E2 groups contained 2% and 4% of clinoptilolite (commercial additive ZeoFeed) respectively, replacing the same amounts of wheat. The hens received feed mixes and drinking water ad libitum. During this 28-day experiment, feed consumption and the number and weight of eggs laid were monitored individually for each hen. At the end of the experiment, the balance test using the indicator method (Cr2O3) was performed in all eight hens in each of the groups. The results of balance tests were then used to calculate the metabolic utilization of selected nutrients (nitrogen, fat, ash, nitrogen-free extracts, starch, gross energy, Ca, P). After the balance tests, blood samples for haematological and biochemical examinations were collected via puncture of the vena basilica. The addition of 2% clinoptilolite to feed mix resulted in a highly significant (P ⪬ 0.01) increase in mean egg weight to 64.69 g, but the addition of 4% clinoptilolite in group E2 resulted in a highly significant (P ⪬ 0.01) decrease in mean egg weight to 62.20 g compared to the control (63.73 g). Moreover, daily feed mix consumption in group E1 decreased to 114 g per one laying hen/day compared to the controls (118 g per one laying hen/day). In group E2 (4% clinoptilolite), daily consumption of feed mix increased compared with the controls to 124 g. The 2% clinoptilolite supplementation of E1 group feed slightly increased metabolic utilization of fat, nitrogen-free extracts, starch and gross energy compared to group C. Results of haematological test of the hens’ blood showed significant changes in haemoglobin, whose values in groups C and E1 were significantly higher (P ⪬ 0.05) than in group E2. Differences in the values of the biochemical indicators monitored (total protein, glucose, cholesterol, triacylglycerols, calcium, phosphorus, magnesium and the AST enzyme) between group C and experimental groups E1 and E2 were not significant and remained within the range of reference values.


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