GB1594883A

GB1594883A - Wool growth enhancer

Info

Publication number: GB1594883A
Application number: GB14841/78A
Authority: GB
Original assignee: American Cyanamid Co
Current assignee: Wyeth Holdings LLC
Priority date: 1977-04-29
Filing date: 1978-04-14
Publication date: 1981-08-05
Also published as: AU3515678A; NZ186954A; BR7802533A; AU519214B2

Description

(54) WOOL GROWTH ENHANCER (71) We, AMERICAN CYANAMID COMPANY, a corporation organised and existing under the laws of the State of Maine, United States of America, of Berdan Avenue, Township of Wayne, New Jersey, United States of America, do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- The present invention relates to a method for enhancing wool growth and favorably altering the ratio of secondary to primary wool follicles in fur-bearing animals.

In a German application, Offenlegungscbrift No. 2501788 there is disclosed 4,5,6,7 - tetrahydrobenzo [6] thien - 4 - ylurea compounds which can be represented by the formula:

wherein X is oxygen or sulfur; U is -CM. or C=O; Rl and R2 represent a plurality of substituents to enhance the biological activity of said formula (I) compounds. This application also discloses methods for utilizing said compounds for the control of undesirable plant species, for promoting animal growth and for enhancing feed efficiency. However, the aforementioned application does not teach or suggest that certain tetrahydrobenzorb]thien-4-ylurea compounds used in the present invention are effective for the enhancement of wool growth, and for favorably altering the ratio of secondary to primarv wool follicles in fur-bearing animals, such as llamas, sheep, goats, rabbits and chinchillas.

It is known that the wool follicle in the sheep is an epidermal structure which produces wool fibres. Follicle development begins in the lamb at about 50 days of fetal age. The follicles formed first, which tend to be larger, and are termed primary follicles, acquare sweat glands and erector muscles. The quota of primary follicles is fully established before birth. Follicles beginning to form at about 90 days of fetal life, the secondary follicles, tend to be smaller than the primaries and develop only sebaceous glands. Proliferation of secondary follicles continue for a short time after birth. This critical period, during which the number of secondarv follicles unalterably and fully establish themselves, varies from breed to breed. In Suffolk sheen, for in stance, this period ends at about 6 weeks after birth, whereas, for Merino sheep, this period can be as long as 12 to 15 weeks.

In general, three main kinds of fiber are recognized in adult sheep. These are wool fibers, hair fibers and kemps, although they are collectivelv loosely regarded as wool. Wool fibers are fine (15-40 microns in diameter), tightly crimped and lack a medulla. Kemp fibers are verv coarse (about 100 microns in diameter) and are fairly short in length. Kemp is undesirable in good wool because it takes up dye poorly and it also causes brittleness. Hairs are intermediate between wool and kemp fibers.

They range in diameter from 50 to 100 microns. Kemp fibers grow only in primary follicles; whereas, hair and wool can grow in both primary and secondary follicles depending on the breed.

At birth, the follicles are packed closely together in the skin and so the follicle density is high. The number cf follicles per square centimeter usually range between 3,000 and 4,000 in a Down breed; whereas, in the Australian Merino the follicle density at birth may be more than 10,000. As the animal grows, the skin expands and the follicle density decreases so that adult figures are about 1,000 follicles per square centimeter in a mountain breed such as the Scottish Blackface, about 1,500 in longwools, 2,000 to 3,000 in Down breeds and between 5,000 and 10,000 in different strains of the Merino. In general, the greater the follicle density, the finer is the fieece.

The numbers of seccndaries to primaries (S/P ratio) is the best indication of the ccndition of follicle population in relation to wool productivity. Since the secondary follicles are wool producing, it follows that the ratio of S/P determines the wool productive capacity of sheep. The S/P ratio in the Suffolk sheep is 5:1; whereas, it is about 22:1 in the Merino whose wool producing capacity is very high. If the number of secondaries could be increased in a sheep, that sheep would therefore produce more wool, thereby enhancing the state of the art.

Similar behaviour is observed in other fur-bearing animals.

Surprisingly, it has now been found in accordance with the present invention that wool growth enhancement and an improved ratio of secondary to primary wool follicles may be attained by parenterally administeIing to a fur-bearing animal at birth, an effective amount of a compound of the formula:

wherein R1 is a hydrogen, C1-C, alkyl, allyl, 2-propynyl or methoxy; R2 is hydrogen or C1-C3 alkyl; and U is -CM2 or -CO-.

The most preferred compounds of the formula (I) are 4,5,6,7-tetrahydrobenzo [b] thien-4-urea and 4,5,6,7-tetrahydro-7-oxobenzo [b]thien-4-ylurea.

Preferably, a wool growth-promoting and follicle ratio altering amount of a tetra hydrobenzo [6] thien-4-ylurea compound is parenterally adminstered to a host animal at birth as one or more subcutanecus implants under the skin of said animal. Prefer- ably, there are used implants that supply 0.0005 mg to 0.2 mg per kg of body weight per day of active compound, and more preferably 0.001 mg to 0.10 mg per kg of body weight per day.

The invention is illustrated by the Examples which follow. Unless otherwise specified, the parts are given by weight and the analysis is in percent.

Example 1.

Evaluation of the Effect of 4,5,6,7 - Tetrahydro - 7 - oxobenzo[b]thien - 4 - ylurea Implants on Favorably altering the Secondary to Primary Wool Follicle Ratio in Sheep Ten sets of twin lambs are implanted at birth. One lamb of each pair receives three implants (36 mg. of compound) in the ear subcutaneously, and the other lamb of the pair receives three implants of castorwax. Skin samples are taken at birth and at 6 weeks of age. The data obtained are averaged and summarized in Table I below.

TABLE I Evaluation of the Effect of 4,5,6 ,7-Tetrahydro-7-oxobienzo[b]thien-4-ylurea Implants on Favorably Altering the Secondary to Primary Wool Follicle Ratio

| Ratio of g Percent Secondary/Primary Change in Wool Follicle Change Ratio at - in Ratio 6 Weet,s At At 6 Weeks at Over h)f in Ratio 6 Weeks Group Birth of Age 6 Weeks Controls Control 2.84 5.69 2.86 Treated 3.06 6.69 3.56 24;47 It can be seen from Table I that the compound used favourably alters the ratio of secondary to primary wool follicles.

Example 2.

The lambs utilized in Example 1 are grazed on a high alpine pasture. Six months from the date of implantation, the lambs are shorn. Greasy fleece weight, staple length and fiber diameter are determined. The data obtained are averaged and summarized in Table II below.

TABLE II Evaluation of the effect of 4,5 ,6 ;7-Tetrahydro-7-oxobenzo[b]thien-4-ylurea on Enhancing Wool Growth, Staple Length and Fiber Diameter

Greasy Fleece Staple .Fiber Diameter Weight Length in Group in kg Percent in cm Percent Microns Control 1.783 100 7.45 100 23.72 Treated 1.9096 107.12 8.45 113.42 23.95 It can be seen from Table II that the compound above noted enhances wool growth and staple length.

The same results were obtained when 4,5,6,7 - tetrahydrobenzo [b]thien - 4ylurea was used instead of 4,5,6,7 - tetrahydro - 7 - oxobenzo[b]thien - 4 - ylurea.

WHAT WE CLAIM IS: 1. A method for promoting wool growth and increasing the secondary to primary wool follicle ratio in a fur-bearing animal, comprising parenterally administering to said animal at birth an effective amount of a compound of the formula:

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. TABLE I Evaluation of the Effect of 4,5,6 ,7-Tetrahydro-7-oxobienzo[b]thien-4-ylurea Implants on Favorably Altering the Secondary to Primary Wool Follicle Ratio | Ratio of g Percent Secondary/Primary Change in Wool Follicle Change Ratio at - in Ratio 6 Weet,s At At 6 Weeks at Over h)f in Ratio 6 Weeks Group Birth of Age 6 Weeks Controls Control 2.84 5.69 2.86 Treated 3.06 6.69 3.56 24;47 It can be seen from Table I that the compound used favourably alters the ratio of secondary to primary wool follicles. Example 2. The lambs utilized in Example 1 are grazed on a high alpine pasture. Six months from the date of implantation, the lambs are shorn. Greasy fleece weight, staple length and fiber diameter are determined. The data obtained are averaged and summarized in Table II below. TABLE II Evaluation of the effect of 4,5 ,6 ;7-Tetrahydro-7-oxobenzo[b]thien-4-ylurea on Enhancing Wool Growth, Staple Length and Fiber Diameter Greasy Fleece Staple .Fiber Diameter Weight Length in Group in kg Percent in cm Percent Microns Control 1.783 100 7.45 100 23.72 Treated 1.9096 107.12 8.45 113.42 23.95 It can be seen from Table II that the compound above noted enhances wool growth and staple length. The same results were obtained when 4,5,6,7 - tetrahydrobenzo [b]thien - 4ylurea was used instead of 4,5,6,7 - tetrahydro - 7 - oxobenzo[b]thien - 4 - ylurea. WHAT WE CLAIM IS:

1. A method for promoting wool growth and increasing the secondary to primary wool follicle ratio in a fur-bearing animal, comprising parenterally administering to said animal at birth an effective amount of a compound of the formula:

wherein R1 is hydrogen, C1-C, alkyl, allyl, 2-propynyl or methoxy and R, is hydrogen or C1-C,alkyl.

2. A method according to Claim 1, wherein said compound is 4,5,6,7-tetrahydro- benzo[b]thien-4-ylurea.

3. A method according to Claim 1 or Claim 2, wherein said animal is a llama, sheep, goat, rabbit or chincilla.

4. A method according to any preceding claim, wherein said compound is parenterally administered as one or more subcutaneous implants beneath the skin of said animal, said implant being sufficient to provide a daily drug release of from 0.0005 mg to 0.2 mg of said component per kg of animal body weight.

5. A method for promoting wool growth and increasing the secondary to primary wool follicle ratio in a fur-bearing animal, comprising parenterally administering to said animal at birth an effective amount of a compound of the formula:

wherein R1 and R2 are as defined in Claim 1.

6. A method according to Claim 5, wherein said compound is 4,5,6,7-tetrahydro 7-oxobenzo[b]thien-4-ylurea.

7. A method according to Claim 5 or Claim 6, wherein said animal is as defined in Claim 3 and/or said compound is administered as defined in Claim 4.

8. A method for promoting wool growth and increasing the secondary to primary wool follicle ratio in a fur-bearing animal, according to Claim 5 and substantially as described in the Example herein.