Breeding Tips for the Shigeshigenami Lineage by Kenichi Ono
Table of Contents
Shigeshigenami, born on April 15, 1972, in Hyogo Prefecture, is one of the most influential Wagyu sires in Japan. Sired by Mokimbo and out of Shigemitsu, Shigeshigenami was bred through a father-daughter mating, making him an inbred bull. After transferring to Miyagi Prefecture in 1974, Shigeshigenami supplied around 150,000 semen straws over his 13-year career.
Initially overlooked due to a weak topline and a distinctive black coat, Shigeshigenami’s offspring proved exceptional in carcass quality. His progeny dominated the 1983 All-Japan Meat Cattle Carcass Exhibition, marking the rise of Miyagi’s Wagyu industry, leading to the branding of their Wagyu as “Sendai Beef,” “Wakayanagi Beef,” and others.
Figure 1. Shigeshigenami
Shigeshigenami
Pedigree Background:
Shigeshigenami is a product of the Kumanami line. His ancestry includes Mokimbo (his sire) and Netsutoi (Nakadoi line). His dam, Shigemitsu, produced 14 calves and was known for her longevity and fertility. His bloodline has performed well outside of Hyogo, especially in regions like Iwate, Akita, Hiroshima, and Miyazaki.
Characteristics:
Strengths:
- Exceptional marbling, particularly in the thigh
- Strong genetic influence
- High fertility and longevity
- Quality meat color, fat quality, and texture
- Gentle temperament
Weaknesses:
- Inconsistent marbling
- Late maturity
- Weak topline and rump shape
- Limited growth rate, milk production, and shoulder thickness
Despite these shortcomings, Shigeshigenami’s genetic power has had a lasting impact on Wagyu breeding in Japan.
Figure 2. TF148 Itoshigenami
Itoshigenami (TF148)
Itoshigenami TF148, a prized 75% Tajima and 25% Fujiyoshi bull, has established himself as one of the most potent sires in fullblood Wagyu breeding programs. His bloodlines bring exceptional marbling and carcass quality, with lineage deeply rooted in the Kumanami family of the Tajima line, famous for producing elite marbling genetics. His daughters, paired with Suzutani descendants like Sanjirou and Shigeshigetani, present unique opportunities for breeders to enhance both maternal traits and meat quality in their herds.
Bloodline Insight:
Itoshigenami TF148 is a direct descendant of the Kumanami line This lineage is known for potent marbling genes, a hallmark trait of Wagyu beef. When planning a breeding program, consider that Itoshigenami’s medium-framed structure (1,650 pounds) adds balance to both carcass quality and conformation. His 75% Tajima blood carries superior marbling, while the 25% Fujiyoshi adds size and maternal traits.
Key Traits:
Itoshigenami TF148 possesses exceptional marbling potential, excellent conformation, and medium frame- this makes him ideal for crossing with cows that possess complementary size, growth, and maternal characteristics.
We have inventory of Itoshigenami TF148 available for $200 per straw. Please reach out to us via our contact form to order today!
Points to consider when breeding
Crossbreeding to Address Shoulder Width and Thigh Fullness:
Challenge:
Bulls from the Shigeshigenami line, such as Itoshigenami TF148, may show narrower shoulder width and thigh fullness. This is a common trait in this lineage, which focuses heavily on marbling and meat quality, sometimes at the expense of body structure.
Solution:
To improve these traits, it’s advisable to cross Itoshigenami progeny with bulls from lines known for broader frames and deeper bodies such as:
1) Itosakura Line (Dai 7 Itozakura): This line contributes size, body depth, and structural improvements. It can complement the high marbling potential of the Shigeshigenami line while improving shoulder and loin muscle width.
2. Yasufuku Line (Yasufuku J930): Known for excellent meat quality and moderate body structure, Yasufuku bloodlines can help stabilize and enhance marbling without compromising structural traits.
Breeding Tip:
Avoid pairing Itoshigenami daughters with bulls from bloodlines that are prone to narrow loin muscles, as this can exacerbate the lack of shoulder width and thigh fullness. Instead, focus on lines that balance structure with high marbling potential.
Managing Fattening Period and Reproduction in Japanese Black Cattle and F1
Challenge:
Both Japanese Black cattle and F1 crosses tend to mature later, which means they require a longer fattening period for optimal marbling development. Shortening the fattening period too much may lead to a decline in performance, particularly in marbling quality and overall carcass yield.
Solution:
Focus on maintaining a balanced fattening period that allows for proper development of marbling and carcass quality.
1. Fattening Period: Ensure that the fattening period lasts long enough (e.g., 540 days or more) to allow for late-maturing traits, such as marbling, to fully develop. It is recommended to feed F1 crosses for at least 500 days to achieve the desired level of marbling and carcass weight.
2. Reproduction Timing: Care should be taken to avoid breeding cows too early. Breeding cows before they are fully mature can lead to reproductive issues and reduce the performance of offspring. Aim for breeding age to be around 24-30 months for optimal reproductive performance and calf health.
Breeding Tip:
Moderation is key. Ensure the fattening process isn’t shortened excessively, and avoid breeding cows too early in their development to achieve better meat quality and reproductive success.
Mitigating Risks of Genetic Diseases
Challenge:
While genetic diseases can be a concern in highly inbred lines, the Itoshigenami TF148 and Suzutani bloodlines have relatively low concerns regarding genetic diseases. This makes them particularly valuable for future breeding programs that focus on producing healthy, productive cattle.
Solution:
Although the risk of genetic diseases is minimal, breeders should still perform genetic testing to ensure no hidden recessive genes could impact herd health.
1. Genetic Diversity: To further reduce the risk of inbreeding, it’s a good practice to introduce genetic diversity through occasional outcrosses with unrelated, high-quality bulls. This helps maintain a healthy gene pool and prevents the accumulation of deleterious genes.
2. Disease Surveillance: Regular health screenings and genetic testing should be part of your breeding program, even if the bloodline has low risk. This ensures you can catch any potential issues early and maintain a healthy herd.
Breeding Tip:
Use genetic testing to track potential risks, but also capitalize on the low incidence of genetic diseases by continuing to breed within this valuable line. Introducing occasional genetic diversity helps maintain herd vitality.
Optimizing Carcass Quality
Itoshigenami TF148 excels in carcass traits, particularly in enhancing marbling, a key characteristic of premium Wagyu. By strategically pairing him with Sanjirou or Shigeshigetani progeny, breeders can optimize both carcass weight and quality, achieving high marbling scores and large ribeye areas.
Marbling Strategy:
The strong marbling genes from the Kumanami line, combined with Suzutani’s influence, result in offspring with higher beef marbling standards (BMS). This combination ensures that a high percentage of progeny will exceed industry standards for meat quality, especially in markets such as Japan and Australia.
Breeding Tip:
Focus on retaining heifers from crosses between Itoshigenami and Sanjirou or Shigeshigetani bloodlines. These females will possess excellent maternal traits and high potential to pass on premium marbling and carcass quality to their offspring.
Enhancing Maternal Traits
Itoshigenami TF148 offers great maternal potential, particularly when crossed with Suzutani-related bulls such as Sanjirou or Shigeshigetani. His daughters are known for their excellent conformation and ability to produce high-quality beef calves. Pairing Itoshigenami’s daughters with larger-framed bulls, like TF151 Itozurudoi, can further enhance maternal capacity and milk production in Fullblood Wagyu herds.
Breeding Tip:
To improve maternal traits and early maturing characteristics, breed Itoshigenami daughters with larger-framed bulls, such as TF151, whose early maturing traits produce excellent milk and mothering ability. This strategy ensures well-balanced offspring with both superior meat quality and strong maternal performance.
Long-Term Breeding Program
A sustainable long-term breeding strategy involves cycling Itoshigenami TF148’s genetics with other top Wagyu lines. Introducing Suzutani’s descendants (Sanjirou and Shigeshigetani) periodically will maintain a balance between marbling, meat quality, and growth traits.
Generational Crossing:
For optimal genetic diversity while preserving elite traits, consider crossing Itoshigenami’s progeny with well-known bulls like TF151 or Michifuku in later generations. This ensures a robust genetic pool while maintaining the highest standards of carcass quality.
Itoshigenami TF148 and the Suzutani line offer unparalleled potential in fullblood Wagyu breeding. With a thoughtful breeding strategy focused on marbling, carcass quality, and maternal traits, breeders can unlock the full potential of this exceptional lineage, producing Wagyu that consistently meets the highest global standards.
References
小野健一. 日本名牛百選〔改訂版〕. 肉牛新報社.
