Immediate Closed Reduction Technique for Cervical Spine Dislocations

Oae Kazunori,Kamei Naosuke,Sawano Makoto,Yahata Tadashi,Morii Hokuto,Adachi Nobuo,Inokuchi Koichi 대한척추외과학회 2023 Asian Spine Journal Vol.17 No.5

Study Design: Retrospective study.Purpose: This research aimed to assess the clinical outcomes of patients with traumatic cervical spine dislocation who underwent closed reduction employing our approach.Overview of Literature: Bedside closed reduction is the quickest procedure for repairing traumatic cervical spine dislocations; nevertheless, it also possesses the risk of neurological deterioration.Methods: For closed reduction, the patient’s head was elevated on a motorized bed, the cervical spine was placed at the midline, traction of 10 kg was applied, the motorized bed was gradually returned to a flat position, the head was lifted off the bed, and the cervical spine was slowly adjusted to a flexed position. The weight of traction was elevated by 5-kg increments until the positional shift was attained. Subsequently, the bed was gradually tilted while traction was applied again to return the cervical spine to the midline position.Results: Of the 43 cases of cervical spine dislocation, closed reduction was carried out in 40 cases, of which 36 were successful. During repositioning, three patients experienced a temporary worsening of their neck pain and neurological symptoms that enhanced when the cervical spine was flexed. Closed reduction was conducted while the patient was awake; nevertheless, sedation was needed in three cases. Among the 24 patients whose pretreatment paralysis had been characterized by American Spinal Injury Association Impairment Scale (AIS) grades A–C, seven patients (29.2%) demonstrated an enhancement of two or more AIS grades at the last observation.Conclusions: Our closed reduction approach safely repaired traumatic cervical spine dislocations.

Effects of preselection of genotyped animals on reliability and bias of genomic prediction in dairy cattle

Kenji Togashi,Kazunori Adachi,Kazuhito Kurogi,Takanori Yasumori,Kouichi Tokunaka,Atsushi Ogino,Yoshiyuki Miyazaki,Toshio Watanabe,Tsutomu Takahashi,Kimihiro Moribe 아세아·태평양축산학회 2019 Animal Bioscience Vol.32 No.2

Objective: Models for genomic selection assume that the reference population is an unselected population. However, in practice, genotyped individuals, such as progeny-tested bulls, are highly selected, and the reference population is created after preselection. In dairy cattle, the intensity of selection is higher in males than in females, suggesting that cows can be added to the reference population with less bias and loss of accuracy. The objective is to develop formulas applied to any genomic prediction studies or practice with preselected animals as reference population. Methods: We developed formulas for calculating the reliability and bias of genomically enhanced breeding values (GEBV) in the reference population where individuals are preselected on estimated breeding values. Based on the formulas presented, deterministic simulation was conducted by varying heritability, preselection percentage, and the reference population size. Results: The number of bulls equal to a cow regarding the reliability of GEBV was expressed through a simple formula for the reference population consisting of preselected animals. The bull population was vastly superior to the cow population regarding the reliability of GEBV for low-heritability traits. However, the superiority of reliability from the bull reference population over the cow population decreased as heritability increased. Bias was greater for bulls than cows. Bias and reduction in reliability of GEBV due to preselection was alleviated by expanding reference population. Conclusion: Cows are easier in expanding reference population size compared with bulls and alleviate bias and reduction in reliability of GEBV of bulls which are highly preselected than cows by expanding the cow reference population.

Predicting the rate of inbreeding in populations undergoing four-path selection on genomically enhanced breeding values

Togashi Kenji,Adachi Kazunori,Kurogi Kazuhito,Yasumori Takanori,Watanabe Toshio,Toda Shohei,Matsubara Satoshi,Hirohama Kiyohide,Takahashi Tsutomu,Matsuo Shoichi 아세아·태평양축산학회 2022 Animal Bioscience Vol.35 No.6

Objective: A formula is needed that is practical for current livestock breeding methods and that predicts the approximate rate of inbreeding (ΔF) in populations where selection is performed according to four-path programs (sires to breed sons, sires to breed daughters, dams to breed sons, and dams to breed daughters). The formula widely used to predict inbreeding neglects selection, we need to develop a new formula that can be applied with or without selection. Methods: The core of the prediction is to incorporate the long-tern genetic influence of the selected parents in four-selection paths executed as sires to breed sons, sires to breed daughters, dams to breed sons, and dams to breed daughters. The rate of inbreeding was computed as the magnitude that is proportional to the sum of squared long-term genetic contributions of the parents of four-selection paths to the selected offspring. Results: We developed a formula to predict the rate of inbreeding in populations undergoing four-path selection on genomically enhanced breeding values and with discrete generations. The new formula can be applied with or without selection. Neglecting the effects of selection led to underestimation of the rate of inbreeding by 40% to 45%. Conclusion: The formula we developed here would be highly useful as a practical method for predicting the approximate rate of inbreeding (ΔF) in populations where selection is performed according to four-path programs. Objective: A formula is needed that is practical for current livestock breeding methods and that predicts the approximate rate of inbreeding (∆F) in populations where selection is performed according to four-path programs (sires to breed sons, sires to breed daughters, dams to breed sons, and dams to breed daughters). The formula widely used to predict inbreeding neglects selection, we need to develop a new formula that can be applied with or without selection.Methods: The core of the prediction is to incorporate the long-tern genetic influence of the selected parents in four-selection paths executed as sires to breed sons, sires to breed daughters, dams to breed sons, and dams to breed daughters. The rate of inbreeding was computed as the magnitude that is proportional to the sum of squared long-term genetic contributions of the parents of four-selection paths to the selected offspring.Results: We developed a formula to predict the rate of inbreeding in populations undergoing four-path selection on genomically enhanced breeding values and with discrete generations. The new formula can be applied with or without selection. Neglecting the effects of selection led to underestimation of the rate of inbreeding by 40% to 45%.Conclusion: The formula we developed here would be highly useful as a practical method for predicting the approximate rate of inbreeding (ΔF) in populations where selection is performed according to four-path programs.

Effects of selection index coefficients that ignore reliability on economic weights and selection responses during practical selection

Kenji Togashi,Kazunori Adachi,Takanori Yasumori,Kazuhito Kurogi,Takayoshi Nozaki,Akio Onogi,Yamato Atagi,Tsutomu Takahashi 아세아·태평양축산학회 2018 Animal Bioscience Vol.31 No.1

Objective: In practical breeding, selection is often performed by ignoring the accuracy of evaluations and applying economic weights directly to the selection index coefficients of genetically standardized traits. The denominator of the standardized component trait of estimated genetic evaluations in practical selection varies with its reliability. Whereas theoretical methods for calculating the selection index coefficients of genetically standardized traits account for this variation, practical selection ignores reliability and assumes that it is equal to unity for each trait. The purpose of this study was to clarify the effects of ignoring the accuracy of the standardized component trait in selection criteria on selection responses and economic weights in retrospect. Methods: Theoretical methods were presented accounting for reliability of estimated genetic evaluations for the selection index composed of genetically standardized traits. Results: Selection responses and economic weights in retrospect resulting from practical selection were greater than those resulting from theoretical selection accounting for reliability when the accuracy of the estimated breeding value (EBV) or genomically enhanced breeding value (GEBV) was lower than those of the other traits in the index, but the opposite occurred when the accuracy of the EBV or GEBV was greater than those of the other traits. This trend was more conspicuous for traits with low economic weights than for those with high weights. Conclusion: Failure of the practical index to account for reliability yielded economic weights in retrospect that differed from those obtained with the theoretical index. Our results indicated that practical indices that ignore reliability delay genetic improvement. Therefore, selection practices need to account for reliability, especially when the reliabilities of the traits included in the index vary widely.

Selection on milk production and conformation traits during the last two decades in Japan

Kenji Togashi,Takefumi Osawa,Kazunori Adachi,Kazuhito Kurogi,Kota Tokunaka,Takanori Yasumori,Tsutomu Takahashi,Kimihiro Moribe 아세아·태평양축산학회 2019 Animal Bioscience Vol.32 No.2

Objective: The purpose of this study was to compare intended and actual yearly genetic gains for milk production and conformation traits and to investigate the simple selection criterion practiced among milk production and conformation traits during the last two decades in Japan. Learning how to utilize the information on intended and actual genetic gains during the last two decades into the genomic era is vital. Methods: Genetic superiority for each trait for four paths of selection (sires to breed bulls [SB], sires to breed cows [SC], dams to breed bulls [DB], and dams to breed cows [DC]) was estimated. Actual practiced simple selection criteria were investigated among milk production and conformation traits and relative emphasis on milk production and conformation traits was compared. Results: Selection differentials in milk production traits were greater than those of conformation traits in all four paths of selection. Realized yearly genetic gain was less than that intended for milk production traits. Actual annual genetic gain for conformation traits was equivalent to or greater than intended. Retrospective selection weights of milk production and conformation traits were 0.73:0.27 and 0.56:0.44 for intended and realized genetic gains, respectively. Conclusion: Selection was aimed more toward increasing genetic gain in milk production than toward conformation traits over the past two decades in Japan. In contrast, actual annual genetic gain for conformation traits was equivalent to or greater than intended. Balanced selection between milk production and conformation traits tended to be favored during actual selection. Each of four paths of selection (SB, SC, DB, and DC) has played an individual and important role. With shortening generation interval in the genomic era, a young sire arises before the completion of sire’s daughters’ milk production records. How to integrate these four paths of selection in the genomic era is vital.