# Shikoku Ken (四国犬) Nihon Ken — Shikoku Ken. Breed health: 4,169 dogs, 0 founders, gene diversity 94.37%. See all Shikoku Ken: https://nihonken.org/pedigree/browse?breed=shikoku&format=md ## Overview A free population-genetics overview across the 4,169 Shikoku Ken in the database — gene diversity, inbreeding over time, and the ancestors shaping the lines. Every figure is a floor on incomplete pedigrees: true values may be higher. ## Genetic diversity - **Dogs:** 4,169 - **Founders:** 0 - **Gene diversity:** 94.37% - **Mean kinship:** 5.63% · sampled estimate - **Effective population (Ne):** Not estimable — Mean inbreeding is not rising in the data (ΔF ≤ 0), so Ne is not estimable. Pedigree-based estimate from the rate of inbreeding, not a census Ne; a floor given incomplete pedigrees. ## Inbreeding over time Mean cached COI per birth-year cohort (3,252 dogs with a computed COI). Population means, not individual COIs. 1938 — 0.00% (1 dogs) 1946 — 0.00% (1 dogs) 1948 — 23.24% (2 dogs) 1949 — 2.34% (1 dogs) 1950 — 2.34% (1 dogs) 1951 — 30.27% (1 dogs) 1952 — 5.57% (2 dogs) 1953 — 16.01% (2 dogs) 1954 — 21.42% (4 dogs) 1955 — 11.67% (2 dogs) 1956 — 6.97% (3 dogs) 1957 — 18.63% (3 dogs) 1958 — 9.67% (10 dogs) 1959 — 13.44% (12 dogs) 1960 — 10.38% (6 dogs) 1961 — 16.83% (13 dogs) 1962 — 19.04% (6 dogs) 1963 — 19.94% (9 dogs) 1964 — 19.87% (6 dogs) 1965 — 14.27% (11 dogs) 1966 — 11.72% (4 dogs) 1967 — 16.37% (7 dogs) 1968 — 11.75% (11 dogs) 1969 — 13.96% (6 dogs) 1970 — 13.18% (3 dogs) 1971 — 24.85% (4 dogs) 1972 — 19.30% (5 dogs) 1973 — 17.39% (7 dogs) 1974 — 9.26% (2 dogs) 1975 — 7.94% (3 dogs) 1976 — 16.01% (6 dogs) 1977 — 9.37% (5 dogs) 1978 — 14.25% (9 dogs) 1979 — 16.70% (7 dogs) 1980 — 13.44% (10 dogs) 1981 — 16.34% (10 dogs) 1982 — 12.17% (14 dogs) 1983 — 14.11% (15 dogs) 1984 — 7.63% (5 dogs) 1985 — 10.84% (16 dogs) 1986 — 11.77% (10 dogs) 1987 — 9.60% (25 dogs) 1988 — 11.71% (14 dogs) 1989 — 9.14% (14 dogs) 1990 — 11.35% (16 dogs) 1991 — 14.83% (10 dogs) 1992 — 13.10% (10 dogs) 1993 — 9.61% (15 dogs) 1994 — 12.69% (9 dogs) 1995 — 13.92% (9 dogs) 1996 — 10.72% (12 dogs) 1997 — 8.10% (4 dogs) 1998 — 18.58% (6 dogs) 1999 — 12.30% (6 dogs) 2000 — 11.43% (8 dogs) 2001 — 12.88% (10 dogs) 2002 — 4.29% (1 dogs) 2003 — 17.11% (6 dogs) 2004 — 16.38% (3 dogs) 2005 — 11.53% (16 dogs) 2006 — 12.80% (23 dogs) 2007 — 12.87% (19 dogs) 2008 — 14.23% (17 dogs) 2009 — 12.93% (23 dogs) 2010 — 12.75% (43 dogs) 2011 — 14.50% (37 dogs) 2012 — 13.58% (50 dogs) 2013 — 13.52% (58 dogs) 2014 — 11.25% (86 dogs) 2015 — 12.22% (90 dogs) 2016 — 12.83% (140 dogs) 2017 — 12.47% (111 dogs) 2018 — 12.44% (148 dogs) 2019 — 11.65% (158 dogs) 2020 — 9.25% (169 dogs) 2021 — 11.03% (205 dogs) 2022 — 9.43% (119 dogs) 2023 — 11.21% (109 dogs) 2024 — 9.95% (124 dogs) 2025 — 9.65% (99 dogs) 2026 — 9.54% (7 dogs) ## Most influential dogs Effective number of ancestors: 10.8. The modern Shikoku Ken gene pool is as concentrated as if 10.8 equally used dogs had produced it. Ranked by each dog's own contribution to the 1,738 Shikoku Ken born since 2011 with a recorded pedigree (as of 2026-10-13): the part of the modern gene pool that passes through that dog and through no dog ranked above it. The top 20 account for 82.1% of it. A dog's reach, the share of pedigrees it appears in, is a minimum: a pedigree that stops early can hide descent, never invent it. Own contributions and the effective number of ancestors are estimates from the recorded pedigrees, and can move either way as more ancestry is recorded. - **#1:** [Iyoshunryuu Go Seikou Sou (1970) · own contribution 23.4% · in 99.8% of pedigrees](https://nihonken.org/pedigree/dogs/96471a0b-bb27-4153-bcc3-393e37b7bdfb) - **#2:** [Teita Go (1953) · own contribution 12.8% · in 99.8% of pedigrees](https://nihonken.org/pedigree/dogs/9c71a14f-290e-4b75-9ae5-99e039cc6ec3) - **#3:** [Gakuhou Go Mabi Tabuchi Sou · own contribution 8.9% · in 99.3% of pedigrees](https://nihonken.org/pedigree/dogs/adf0cecf-63c9-47b6-985f-ce9994ca1e3f) - **#4:** [Kiko Go Mabi Tabuchi Sou · own contribution 6.4% · in 99.3% of pedigrees](https://nihonken.org/pedigree/dogs/f3c3a726-5cc3-4a92-82ad-c060cc3ad0a7) - **#5:** [Daigorou Go Houjou Ikenaga (Katashiro Ikenaga) · own contribution 4.1% · in 86.2% of pedigrees](https://nihonken.org/pedigree/dogs/d30e3684-10a9-4b9d-9bc2-fda2f93073f7) - **#6:** [松風号 元禄荘 · own contribution 3.7% · in 99.8% of pedigrees](https://nihonken.org/pedigree/dogs/05d3277a-d976-4f0c-93d3-d460f6ab2d28) - **#7:** [Gunreime Go Sanuki Sunayama Sou · own contribution 3% · in 99.3% of pedigrees](https://nihonken.org/pedigree/dogs/996d748e-4bde-46fa-8c53-3f1aca4d5938) - **#8:** [Sekihoume Go Iyo Temman sou (2006) · own contribution 2.6% · in 43.7% of pedigrees](https://nihonken.org/pedigree/dogs/89a3b21e-db44-4f80-8e18-6a98b122fb2f) - **#9:** [Mutsu Go · own contribution 2.4% · in 99.8% of pedigrees](https://nihonken.org/pedigree/dogs/89851e46-e3bc-4f63-be11-3231dd42ae1f) - **#10:** [Kazuhideryuu Go Kazusa Okazawa Sou · own contribution 1.9% · in 28% of pedigrees](https://nihonken.org/pedigree/dogs/28e55c55-0705-47b1-8bf5-da4057af35e9) - **#11:** [Oboro (2007) · own contribution 1.8% · in 30.6% of pedigrees](https://nihonken.org/pedigree/dogs/49e0507c-5769-4723-bfa0-2994fcbea98a) - **#12:** [Fukuyama no Matsumine Go Fukuyama Ichiza (1999) · own contribution 1.7% · in 92.8% of pedigrees](https://nihonken.org/pedigree/dogs/e0f9c5d9-99b5-4efd-ba7e-ed3c1a883ec3) - **#13:** [Shougaku Go Marufuku Sou (1992) · own contribution 1.5% · in 92.5% of pedigrees](https://nihonken.org/pedigree/dogs/810c4127-4df5-40c5-a319-03bcf87d686f) - **#14:** [赤秀峰号 新居親和荘 · own contribution 1.5% · in 85.1% of pedigrees](https://nihonken.org/pedigree/dogs/d0535c05-0929-4bbf-bd53-905940b37a34) - **#15:** [Heisei Shuuritsumi Go Shouyousou (1995) · own contribution 1.3% · in 97.5% of pedigrees](https://nihonken.org/pedigree/dogs/3c432cd5-ac1f-44b4-8710-4088d2fc180d) - **#16:** [Reikou go Yukiharu sou (1983) · own contribution 1.2% · in 99.3% of pedigrees](https://nihonken.org/pedigree/dogs/fae88990-f96a-410c-a8c3-1d4d3507ceca) - **#17:** [Tochitsurume Go · own contribution 1% · in 49.7% of pedigrees](https://nihonken.org/pedigree/dogs/f40f5aee-acd8-4d5f-b9c9-d893d75d6e2d) - **#18:** [Daigaku Go Nagisa (1983) · own contribution 0.96% · in 99.4% of pedigrees](https://nihonken.org/pedigree/dogs/6e13ffda-4f4f-44cb-9d8d-3864c8993238) - **#19:** [Setome Go Sanuki Sunayama Sou (1995) · own contribution 0.92% · in 85.3% of pedigrees](https://nihonken.org/pedigree/dogs/ee13811f-b828-4e33-a36a-e70670aa080d) - **#20:** [Oushun Go Shibukawa Kato Kensha · own contribution 0.92% · in 81% of pedigrees](https://nihonken.org/pedigree/dogs/eefb8a13-a6ba-40cd-a00e-af6be8c38e7f) ## Dogs - **Chidori go Hachidori Sou 蜂鳥荘:** [AKC HP73315601](https://nihonken.org/pedigree/dogs/4cda9748-2722-4d75-b83e-5bd508438a21) - **Choushun Go 長春号 高知古城:** [NIPPO 668](https://nihonken.org/pedigree/dogs/85acc022-f0c0-4164-acc8-53f88801fbf7) - **Kiyohime Go Ayumi Sou 清姫号 あゆみ荘:** [NIPPO H28-160](https://nihonken.org/pedigree/dogs/08ff670c-ce96-429f-bb3e-50b2dc6cb0a9) - **Kusunoki 楠号 岡山安原:** [NIPPO 483](https://nihonken.org/pedigree/dogs/da6e8764-6f30-4985-97db-f1a0863d1a2c) - **丹峰快雲号 丹波下鴨荘:** [NIPPO R4-277](https://nihonken.org/pedigree/dogs/e8cc6a3a-b4c8-4f19-88a7-43087326c52d) - **伊予の紅号 辻華荘:** [](https://nihonken.org/pedigree/dogs/24450fda-c1e3-4971-8fa5-74d57b305b5f) - **宝の帝号 備後吉原荘:** [](https://nihonken.org/pedigree/dogs/70f4745e-8413-4793-ba33-06af5df3d2a7) - **秋竜号 飛騨門前荘:** [NIPPO R5-508](https://nihonken.org/pedigree/dogs/43845bc6-9a67-4c3d-9102-0037e5b3e0c1) - **舞号 讃岐長門荘:** [NIPPO 9-2619](https://nihonken.org/pedigree/dogs/417142f2-71d9-4ffe-a3d7-12d810217838) - **Kikujiro 菊二郎号:** [NIPPO 6170](https://nihonken.org/pedigree/dogs/f430f53e-2600-4356-a2c8-f277611754d0) - **Kikuryoume Go 菊良女号:** [NIPPO 6173](https://nihonken.org/pedigree/dogs/5d793ad1-d8ac-4613-831a-f145fffd9221) - **Kikutaro Go 菊太郎号:** [NIPPO 6169](https://nihonken.org/pedigree/dogs/5110f7a2-dbc8-4147-b518-c0c84baea9b8) - **一岳号 愛媛金亀荘:** [](https://nihonken.org/pedigree/dogs/caabc495-a25d-44f2-af6f-0c5c0597db57) - **伊予の一郎号 菊間吉井荘:** [NIPPO H28-541](https://nihonken.org/pedigree/dogs/9e17d4a3-bac8-4900-931a-7db39672c421) - **劉太郎号 曽我部荘:** [](https://nihonken.org/pedigree/dogs/5803b207-6a2b-4cb6-b040-0a5fe1b22f28) - **城栄女号 長探舎:** [NIPPO 7-1909](https://nihonken.org/pedigree/dogs/223015fb-d67d-4057-ad3e-64ade2a2ead3) - **多摩乃豪源号 多摩吉秀荘:** [](https://nihonken.org/pedigree/dogs/94d5e819-949e-4ca3-88f9-80629c2f08c1) - **宝の大地号 安芸新月荘:** [](https://nihonken.org/pedigree/dogs/0505f325-0de4-4eab-9485-2e92bd512940) - **Iyo Tsukasa Sou 智乃舞号 伊予司荘:** [NIPPO R4-623](https://nihonken.org/pedigree/dogs/b37de2c4-f766-4903-8040-4c536d173c1e) - **東雲号 東橘:** [NIPPO R2-257](https://nihonken.org/pedigree/dogs/513f2dcc-8dfd-4fed-8b1c-1e10272155f1) - **桃華姫号 たまうら:** [](https://nihonken.org/pedigree/dogs/950629cc-d345-4cc5-8057-e2b93424d9ed) - **福山の秀錦号 福山一座:** [](https://nihonken.org/pedigree/dogs/8d3dfabe-1f6b-41ed-87dd-def3286b80c6) - **翔陽女号 日犬福山荘:** [NIPPO H25-713](https://nihonken.org/pedigree/dogs/c400deab-97e1-4654-beb1-fcca1b9d8a15) - **逢夢号 四国末廣庵:** [](https://nihonken.org/pedigree/dogs/05766bbf-00cf-4f9b-9447-c2bc07624c69) --- **Navigate:** [Home](https://nihonken.org/pedigree/?format=md) · [Search](https://nihonken.org/pedigree/browse?format=md) · [Litters](https://nihonken.org/pedigree/litters?format=md) · [Breeders](https://nihonken.org/pedigree/breeders?format=md) · [LLM guide](https://nihonken.org/pedigree/llms.txt) _Search by name: https://nihonken.org/pedigree/browse?q=NAME&format=md_