- Email: [email protected]
Oviposition-Inducing Activity in the Ovarian Follicles of Different Sizes in the Laying Hen
Oviposition-Inducing Activity in the Ovarian Follicles of Different Sizes in the Laying Hen KOUSAKU TANAKA
Faculty of Agriculture, Kyushu University, Fukuoka-shi,
Japan
(Received for publication July 9, 1975)
POULTRY SCIENCE 55: 714-716, 1976
clutches of more than 8 eggs were killed at two different times, immediately after lay (50 hens) and 1 to 6 hours after ovulation (62 hens), during the middle of a clutch sequence. At autopsy, the preovulatory and ruptured follicles were cut from their respective stalks. The follicles of these two types were classified separately into three groups according to the estimated time before or after ovulation of the test follicle (see Table 1). In the case of the preovulatory follicle, the wall was separated from the yolk. The extraction of the follicle walls or the ruptured follicles for an oviposition-inducing factor was as described previously (Tanaka and Nakada, 1974), except that 15 ml. of a saline solution (10 ml. in the first extraction and 5 ml. in the second) per 0.9 g. of acetone-treated tissue powder were used. For the oviposition test to estimate the activity of this factor in the follicular extract, a dose of 13 ml. of the extract with 4 mg. of heparin sodium was injected into the wing-vein of the hen during a period when a soft-shelled egg was present in the uterus.
INTRODUCTION
R
OTHCHILD and Fraps (1944a) first demonstrated that removal of the most recently ruptured follicle caused a retarded oviposition and suggested that the time of normal lay of the hen's egg appeared to be under the control of the ruptured follicle from which that egg had originated. In this connection, they (1944b) also indicated that an extraovarian, light-sensitive agent was involved in the process of oviposition. Recently, Tanaka and Nakada (1974) demonstrated the presence of an oviposition-inducing factor in the most recently ruptured follicle. The present study is concerned with the ultimate attempt to determine the participation of the ovarian oviposition-inducing factor in controlling oviposition in the hen. Before this could be done, it was necessary to learn what changes occur in the activity of the factor in the ovarian follicle of the laying hen. MATERIALS AND METHODS Hens belonging to a commercial hybrid strain bred for egg laying were used. The record of lay and conditions of the hens were as described previously (Tanaka and Nakada, 1974). A total number of 112 hens producing
RESULTS AND DISCUSSION Table 1 shows the effect of the follicular extracts on the premature oviposition of soft714
Downloaded from http://ps.oxfordjournals.org/ at Simon Fraser University on May 31, 2015
ABSTRACT The walls of the preovulatory follicles and the ruptured follicles collected during the middle of a clutch sequence were extracted separately for an oviposition-inducing factor. The activity of this factor in the follicular extracts was estimated by single intravenous injection of the extracts to hens with a soft-shelled egg in the uterus. Administration of the extracts from either follicles destined to ovulate in 20 to 27 hours or follicles in 46 to 53 hours failed to induce premature oviposition of soft-shelled egg in any of the hens treated. In contrast, the largest follicle within 1 hour prior to the expected ovulation exhibited a high activity for inducing premature ovipositions. This level of the activity seemed to be persisted in the subsequent ruptured follicle for several hours, followed by considerable decrease in activity after about one day or more days.
OVIPOSITION-INDUCING ACTIVITY OF FOLLICLES
715
cles aged 1 to 6 hours after rupture was given to 4 hens, all of these hens laid prematurely within 15 minutes. Only one out of 3 hens which received the extract from the ruptured follicles aged 27 to 34 hours laid prematurely. Administration of the extract from the smaller ruptured follicles aged more than 56 hours failed to cause premature oviposition in any of the 3 hens injected. In the case of the
On the other hand, there is evidence that removal of the largest follicle within a clutch causes a delayed oviposition of a few hours and that removal of the most recently ruptured follicle leads to a delayed oviposition far beyond the expected time (Rothchild and Fraps, 1944a; Tanaka and Nakada, 1974). In view of these facts and the present experimental results, it is suggested that both the
Downloaded from http://ps.oxfordjournals.org/ at Simon Fraser University on May 31, 2015
TABLE 1.—The effect of ovarian follicular extracts ruptured follicle, however, most of the hens on the premature oviposition of soft-shelled egg in which failed to lay prematurely showed a the uterus similar behaviour as described above in reHr. sponse to the injection of the extracts. before As far as oviposition test is concerned, it seems possible that the oviposition-inducing activity in the preovulatory follicle increases of test Laid rapidly as the follicle approaches rupture and Follicle follicle Injected soft extracted (range) (i.v.)c egg attains to a peak level. This level of the Preovulatory 45-53 5 0 activity appeared to be persisted in the subsefollicle" 20-27 6 0 quent ruptured follicle for several hours, <1 4 4 followed by considerable decrease in activity Ruptured follicle 1-6 4 4 after about one day or more days. It is of 27-34 3 1 interest to note that the high activity for >56 b 3 0 a inducing oviposition in the largest follicle near The follicle wall after separation from the yolk was used for extraction. the time of ovulation is coincident with the b The ruptured follicle smaller than about 0.1 g. time of normal oviposition which occurs of cwet weight was not included. Intravenous injection. shortly before ovulation (Warren and Scott, 1935). Moreover, recent study at this laboratory (unpublished) revealed that partially shelled egg. When 5 hens were injected intrapurified ovarian oviposition-inducing factor venously with the extract from the follicles caused a contraction of the uterine muscle destined to ovulate in 46 to 53 hours, no strip isolated from the laying hen and that premature oviposition was induced. Similarthe factor was diffusible through a cellophane ly, administration of the extract from the bag against water. It is unlikely that this follicles destined to ovulate in 20 to 27 hours aqueous factor is oxytocin, since intravenous failed to cause premature oviposition in any injection of oxytocin (2.5 U. /hen) for inducof the 6 hens treated, although half of these ing premature oviposition caused a paled hens everted their cloacae shortly after injeccomb immediately after injection but such tion and showed pre-laying behaviour involva reaction is not observed in the hens which ing changes in rate of respiration, stance and received either the follicular extracts or the contraction of the body muscles. In contrast, crude extract of the fowl posterior pituitary three put of 4 hens which received the extract (confirmed at this laboratory). Accordingly, from the largest follicles removed within 1 it may be suggested that the factor is of hour of expected ovulation expelled softrelatively small molecule and is something shelled eggs within 20 minutes after injection like posterior pituitary hormones found in and one hen within 40 minutes. the fowl. When the extract from the ruptured folli-
716
K.
TANAKA
preovulatory and ruptured follicles m a y participate in controlling oviposition. REFERENCES Rothchild, I., and R. M. Fraps, 1944a. On the function of the ruptured ovarian follicle of the domestic fowl. Proc. Soc. Exp. Biol. Med. 56: 79-82.
Rothchild, I., and R. M. Fraps, 1944b. Relation between light-dark rhythms and hour of lay of eggs experimentally retained in the hen. Endocrinology, 35: 355-362. Tanaka, K., and T. Nakada, 1974. Participation of the ovarian follicle in control of time of oviposition in the domestic fowl. Poultry Sci. 53: 2120-2125. Warren, D. C , and H. M. Scott, 1935. The time factor in egg formation. Poultry Sci. 14: 195-207.
Antithyroid Activity of Goitrin in Chicks
(Received for publication July 9, 1975)
ABSTRACT Antithyroid activity of orally administered goitrin was assessed by parallel-line assay in chicks using four indices. The relative potency of goitrin in chicks was estimated to be approximately 0.31 times the potency of PTU in causing enlargement of thyroid gland, 0.06 times in effect on depression in plasma thyroid hormone, and 0.08 times in inhibitory effects on biosynthesis of thyroid hormone in the gland. It might be concluded that thyroid hormone synthesis is not so much suppressed to the degree expected from the enlargement of thyroid gland when goitrin is administered orally to the chick. POULTRY SCIENCE 55: 716-719,
I
N previous papers ( M a t s u m o t o et al., 1969; Akiba and M a t s u m o t o , 1971), antithyroid effects of (-)-5-vinyl-2-oxazoIidinethione (goitrin), a naturally occurring goitrogen in plants of Brassica family, have been investigated in chicks. T h e relative activity of goitrin compared with synthetic goitrogen has been demonstrated in man and in the rat (Astwood et al., 1949; l i n o , 1961; and F a i m a n et al., 1967), but it has not yet been investigated in chicks. T h e object of the p r e s e n t study was to investigate t h e antithyroid activity of goitrin in chicks. It is well k n o w n that antithyroid substances h a v e complicated a c t i o n s . T h e r e fore, antithyroid activity of goitrin was estimated collectively b y determining the activity of various indices concerning the antithyroid function. MATERIALS AND METHOD Day-old Single C o m b White Leghorn male chicks were fed experimental diet containing
1976
several levels of goitrin or propylthiouracil (PTU). Determined iodine content of the diet w a s 0.67 (j-g./g. on air-dry matter basis. T h e chicks in the control group were fed goitrogen-free diet. Average feed consumption for 14 days was about 180 g. in all groups. On the 14th day of age, chicks were injected subcutaneously in the thigh with carrier-free N a , 3 1 I (15 (jiCi./lOO g. b o d y weight). Six chicks in each group were killed by decapitation after heart puncture at 24 hours after administration of 1 3 I I , and thyroidal m I upt a k e , plasma % P B 1 3 ' I (protein b o u n d iodine) and distribution of 131 I c o m p o u n d s in the thyroid lobes were determined. Detailed p r o c e d u r e s for the determination of thyroidal 131 1 u p t a k e , plasma P B 1 3 1 I and distribution I3 of ' I c o m p o u n d s in the gland were described in our previous p a p e r s ( M a t s u m o t o et al., 1969; Akiba and M a t s u m o t o , 1971). Estimation of relative p o t e n c y of goitrin was performed using P T U as an index material by the parallel-line a s s a y (Sakuma, 1964).
Downloaded from http://ps.oxfordjournals.org/ at Simon Fraser University on May 31, 2015
YUKIO AKIBA AND TATSURO MATSUMOTO
Department of Animal Science, Faculty of Agriculture, Tohoku University, Sendai, Japan
Faculty of Agriculture, Kyushu University, Fukuoka-shi,
Japan
(Received for publication July 9, 1975)
POULTRY SCIENCE 55: 714-716, 1976
clutches of more than 8 eggs were killed at two different times, immediately after lay (50 hens) and 1 to 6 hours after ovulation (62 hens), during the middle of a clutch sequence. At autopsy, the preovulatory and ruptured follicles were cut from their respective stalks. The follicles of these two types were classified separately into three groups according to the estimated time before or after ovulation of the test follicle (see Table 1). In the case of the preovulatory follicle, the wall was separated from the yolk. The extraction of the follicle walls or the ruptured follicles for an oviposition-inducing factor was as described previously (Tanaka and Nakada, 1974), except that 15 ml. of a saline solution (10 ml. in the first extraction and 5 ml. in the second) per 0.9 g. of acetone-treated tissue powder were used. For the oviposition test to estimate the activity of this factor in the follicular extract, a dose of 13 ml. of the extract with 4 mg. of heparin sodium was injected into the wing-vein of the hen during a period when a soft-shelled egg was present in the uterus.
INTRODUCTION
R
OTHCHILD and Fraps (1944a) first demonstrated that removal of the most recently ruptured follicle caused a retarded oviposition and suggested that the time of normal lay of the hen's egg appeared to be under the control of the ruptured follicle from which that egg had originated. In this connection, they (1944b) also indicated that an extraovarian, light-sensitive agent was involved in the process of oviposition. Recently, Tanaka and Nakada (1974) demonstrated the presence of an oviposition-inducing factor in the most recently ruptured follicle. The present study is concerned with the ultimate attempt to determine the participation of the ovarian oviposition-inducing factor in controlling oviposition in the hen. Before this could be done, it was necessary to learn what changes occur in the activity of the factor in the ovarian follicle of the laying hen. MATERIALS AND METHODS Hens belonging to a commercial hybrid strain bred for egg laying were used. The record of lay and conditions of the hens were as described previously (Tanaka and Nakada, 1974). A total number of 112 hens producing
RESULTS AND DISCUSSION Table 1 shows the effect of the follicular extracts on the premature oviposition of soft714
Downloaded from http://ps.oxfordjournals.org/ at Simon Fraser University on May 31, 2015
ABSTRACT The walls of the preovulatory follicles and the ruptured follicles collected during the middle of a clutch sequence were extracted separately for an oviposition-inducing factor. The activity of this factor in the follicular extracts was estimated by single intravenous injection of the extracts to hens with a soft-shelled egg in the uterus. Administration of the extracts from either follicles destined to ovulate in 20 to 27 hours or follicles in 46 to 53 hours failed to induce premature oviposition of soft-shelled egg in any of the hens treated. In contrast, the largest follicle within 1 hour prior to the expected ovulation exhibited a high activity for inducing premature ovipositions. This level of the activity seemed to be persisted in the subsequent ruptured follicle for several hours, followed by considerable decrease in activity after about one day or more days.
OVIPOSITION-INDUCING ACTIVITY OF FOLLICLES
715
cles aged 1 to 6 hours after rupture was given to 4 hens, all of these hens laid prematurely within 15 minutes. Only one out of 3 hens which received the extract from the ruptured follicles aged 27 to 34 hours laid prematurely. Administration of the extract from the smaller ruptured follicles aged more than 56 hours failed to cause premature oviposition in any of the 3 hens injected. In the case of the
On the other hand, there is evidence that removal of the largest follicle within a clutch causes a delayed oviposition of a few hours and that removal of the most recently ruptured follicle leads to a delayed oviposition far beyond the expected time (Rothchild and Fraps, 1944a; Tanaka and Nakada, 1974). In view of these facts and the present experimental results, it is suggested that both the
Downloaded from http://ps.oxfordjournals.org/ at Simon Fraser University on May 31, 2015
TABLE 1.—The effect of ovarian follicular extracts ruptured follicle, however, most of the hens on the premature oviposition of soft-shelled egg in which failed to lay prematurely showed a the uterus similar behaviour as described above in reHr. sponse to the injection of the extracts. before As far as oviposition test is concerned, it seems possible that the oviposition-inducing activity in the preovulatory follicle increases of test Laid rapidly as the follicle approaches rupture and Follicle follicle Injected soft extracted (range) (i.v.)c egg attains to a peak level. This level of the Preovulatory 45-53 5 0 activity appeared to be persisted in the subsefollicle" 20-27 6 0 quent ruptured follicle for several hours, <1 4 4 followed by considerable decrease in activity Ruptured follicle 1-6 4 4 after about one day or more days. It is of 27-34 3 1 interest to note that the high activity for >56 b 3 0 a inducing oviposition in the largest follicle near The follicle wall after separation from the yolk was used for extraction. the time of ovulation is coincident with the b The ruptured follicle smaller than about 0.1 g. time of normal oviposition which occurs of cwet weight was not included. Intravenous injection. shortly before ovulation (Warren and Scott, 1935). Moreover, recent study at this laboratory (unpublished) revealed that partially shelled egg. When 5 hens were injected intrapurified ovarian oviposition-inducing factor venously with the extract from the follicles caused a contraction of the uterine muscle destined to ovulate in 46 to 53 hours, no strip isolated from the laying hen and that premature oviposition was induced. Similarthe factor was diffusible through a cellophane ly, administration of the extract from the bag against water. It is unlikely that this follicles destined to ovulate in 20 to 27 hours aqueous factor is oxytocin, since intravenous failed to cause premature oviposition in any injection of oxytocin (2.5 U. /hen) for inducof the 6 hens treated, although half of these ing premature oviposition caused a paled hens everted their cloacae shortly after injeccomb immediately after injection but such tion and showed pre-laying behaviour involva reaction is not observed in the hens which ing changes in rate of respiration, stance and received either the follicular extracts or the contraction of the body muscles. In contrast, crude extract of the fowl posterior pituitary three put of 4 hens which received the extract (confirmed at this laboratory). Accordingly, from the largest follicles removed within 1 it may be suggested that the factor is of hour of expected ovulation expelled softrelatively small molecule and is something shelled eggs within 20 minutes after injection like posterior pituitary hormones found in and one hen within 40 minutes. the fowl. When the extract from the ruptured folli-
716
K.
TANAKA
preovulatory and ruptured follicles m a y participate in controlling oviposition. REFERENCES Rothchild, I., and R. M. Fraps, 1944a. On the function of the ruptured ovarian follicle of the domestic fowl. Proc. Soc. Exp. Biol. Med. 56: 79-82.
Rothchild, I., and R. M. Fraps, 1944b. Relation between light-dark rhythms and hour of lay of eggs experimentally retained in the hen. Endocrinology, 35: 355-362. Tanaka, K., and T. Nakada, 1974. Participation of the ovarian follicle in control of time of oviposition in the domestic fowl. Poultry Sci. 53: 2120-2125. Warren, D. C , and H. M. Scott, 1935. The time factor in egg formation. Poultry Sci. 14: 195-207.
Antithyroid Activity of Goitrin in Chicks
(Received for publication July 9, 1975)
ABSTRACT Antithyroid activity of orally administered goitrin was assessed by parallel-line assay in chicks using four indices. The relative potency of goitrin in chicks was estimated to be approximately 0.31 times the potency of PTU in causing enlargement of thyroid gland, 0.06 times in effect on depression in plasma thyroid hormone, and 0.08 times in inhibitory effects on biosynthesis of thyroid hormone in the gland. It might be concluded that thyroid hormone synthesis is not so much suppressed to the degree expected from the enlargement of thyroid gland when goitrin is administered orally to the chick. POULTRY SCIENCE 55: 716-719,
I
N previous papers ( M a t s u m o t o et al., 1969; Akiba and M a t s u m o t o , 1971), antithyroid effects of (-)-5-vinyl-2-oxazoIidinethione (goitrin), a naturally occurring goitrogen in plants of Brassica family, have been investigated in chicks. T h e relative activity of goitrin compared with synthetic goitrogen has been demonstrated in man and in the rat (Astwood et al., 1949; l i n o , 1961; and F a i m a n et al., 1967), but it has not yet been investigated in chicks. T h e object of the p r e s e n t study was to investigate t h e antithyroid activity of goitrin in chicks. It is well k n o w n that antithyroid substances h a v e complicated a c t i o n s . T h e r e fore, antithyroid activity of goitrin was estimated collectively b y determining the activity of various indices concerning the antithyroid function. MATERIALS AND METHOD Day-old Single C o m b White Leghorn male chicks were fed experimental diet containing
1976
several levels of goitrin or propylthiouracil (PTU). Determined iodine content of the diet w a s 0.67 (j-g./g. on air-dry matter basis. T h e chicks in the control group were fed goitrogen-free diet. Average feed consumption for 14 days was about 180 g. in all groups. On the 14th day of age, chicks were injected subcutaneously in the thigh with carrier-free N a , 3 1 I (15 (jiCi./lOO g. b o d y weight). Six chicks in each group were killed by decapitation after heart puncture at 24 hours after administration of 1 3 I I , and thyroidal m I upt a k e , plasma % P B 1 3 ' I (protein b o u n d iodine) and distribution of 131 I c o m p o u n d s in the thyroid lobes were determined. Detailed p r o c e d u r e s for the determination of thyroidal 131 1 u p t a k e , plasma P B 1 3 1 I and distribution I3 of ' I c o m p o u n d s in the gland were described in our previous p a p e r s ( M a t s u m o t o et al., 1969; Akiba and M a t s u m o t o , 1971). Estimation of relative p o t e n c y of goitrin was performed using P T U as an index material by the parallel-line a s s a y (Sakuma, 1964).
Downloaded from http://ps.oxfordjournals.org/ at Simon Fraser University on May 31, 2015
YUKIO AKIBA AND TATSURO MATSUMOTO
Department of Animal Science, Faculty of Agriculture, Tohoku University, Sendai, Japan