Some important “normal” mouse breeding characteristics Sexual maturity at roughly 5-8 weeks of age Estrus cycle: 4-5 days day gestation period Average litter size: 6-8 pups Pups must be weaned at 3-4 weeks of age to prevent unplanned matings Coat color can be distinguished starting at about 8-9 days of age
Some important “normal” mouse breeding characteristics Female fertility starts to decline at about 6-8 months of age, while males usually remain fertile for at least a year Females can become pregnant within a day of giving birth (postpartum estrus) Multiple females can be mated with a single male, but not vice versa Males used for breeding must not be housed with other males
(1) 持續交配：雌鼠被允許永久與雄鼠及群體其他成員相 處並產下仔鼠。 此系統乃利用產後發情方式繁殖。 a. 一夫一妻：一隻公鼠一隻母鼠關在一起。 b. 一夫多妻：一隻公鼠及多隻母鼠關在一起。 (2) 暫留交配；在分娩之前將公鼠和母鼠暫時分開。 a. harem 系統，公鼠及母鼠關在一起至分娩前才分開。 b. 人工控制交配系統；公鼠和母鼠關在一起一段充分的 時間進行交配 ( 通常約 1 個星期 ) 。 配種方式
PHEROMONE EFFECTS Lee-Boot Effect Housing female mice in groups will result in synchronization of their estrus cycles. Prolonged absence of male pheromones results in a state of anestrus (lack of a normal estrus cycle). Whitten Effect Estrus can be induced in most group-housed females by adding male mouse urine (or dirty bedding from a male’s cage) to their cage. Bruce Effect Pheromones from a strange male can prevent the implantation of embryos into the uterine walls of a recently bred female. This is why one should not move a female from one male’s cage to another.
Replacement of breeders Replace a breeder pair if: they have not produced a litter in more than two months, they are producing small litters (1-3 pups per litter), they are killing their pups.
( 使用者園地 )
R1 ES cell (129X1/SvJ x 129S1/Sv)F1 Chimera C57BL/6J ICR
From Chimera to Homozygous Null (129 ES cells injected into C57BL/6 host blastocysts) Chimeric mouse ♂ x C57BL/6 ♀ = B6129F1 and/or C57BL/6 B6129F1 coat color agouti, 50% carry targeted alleles +/- B6129F1 ♂ +/- x B6129F1 ♀ +/- = B6129F2 B6129F2 coat color mixed, 25% homozygous -/- founders B6129F2 ♂ -/- x B6129F2 ♀ -/- = B6129F3 B6129F3 coat color mixed, 100% homozygous -/- B6129F3 are used for initially characterizing targeted genes
From 129 to C57BL/6 Congenic B6129F1 ♂ +/- x C57BL/6 ♀ +/+ = B6129N1 25% +/- B6129N1 ♂ +/- x C57BL/6 ♀ +/+ = B6129N2 25% +/- B6129N2 ♂ +/- x C57BL/6 ♀ +/+ = B6129N3 25% +/- B6129N3 ♂ +/- x C57BL/6 ♀ +/+ = B6129N4 25% +/- B6129N4 ♂ +/- x C57BL/6 ♀ +/+ = B6129N5 25% +/-. . B6.129N10 ♂ +/- x B6.129N10 ♀ +/- = B6.129N10F1 25% -/- B6.129N10F1 ♂ -/- x B6.129N10F1 ♀ -/- = B6.129N10F2 100% -/- B6.129N10F2 -/- congenics are suitable for study on defined genetic background
配種紀錄 ( 族譜 )
To properly size a research mouse colony, many factors must be considered, including the following: Number of mice needed, utility of each sex, needs for specific genotypes and age-matched mice Number of strains needed (for example, a cre-lox experiment may require three breeding colonies) Preferred breeding scheme Strain productivity, genotypes and phenotypes affecting productivity, and number of unproductive matings Female’s reproductive life span, average number and frequency of litters Average number of pups per litter, average sex ratio per litter, and percent survival to weaning and adulthood Breeder replacement schedules Cage requirements, mouse room space, pair or trio breeding schemes, and allowable mouse density per cage (ACUC regulations) Sizing Mouse Colonies
Mat. cage 1 Mat. cage 2 Holding cage Holding cage Holding cage Holding cage 7 pups5 pups4 males5 females3 males4 males 3 wks old2 wks old15 wks old 10 wks old8 wks old The progeny from mating cage 1 are ready to be weaned. Three females and four males are found. They are numbered and placed in two cages. The two cages of older progeny are discarded (shaded boxes). Result: no change in cage number. AN EXAMPLE OF LOW-LEVEL MAINTENANCE
Mat. cage 1 Mat. cage 2 Holding cage Holding cage Holding cage Holding cage 8 pups5 pups3 males4 males 3 females newborn3 wks old11 wks old9 wks old4 wks old The progeny from mating cage 2 are ready to be weaned. Two females and three males are found and numbered. The females are added to the cage of 3 females created in week 1, while the males are put into a new cage. The oldest cage of male progeny is discarded (shaded). Result: no change in cage number.
Mat. cage 1 Mat. cage 2 Holding cage Holding cage Holding cage Holding cage 8 pupsNo pups4 males 5 females3 males 1 wk old 9 wks old5 wks old4&5 wks old4 wks old The oldest male progeny can be discarded (shaded). No other action is necessary. Result: cage number reduced to five.
Nomenclature Guidelines for the Laboratory Mice
Rules for Nomenclature of Mouse and Rat Strains and Rat Strains Revised : July Rules for Nomenclature of Genes, Genetic Markers, Alleles, and Mutations in Mouse and Rat Rules for Nomenclature of Genes, Genetic Markers, Alleles, and Mutations in Mouse and Rat Revised: Jan, 2007
Nomenclature of Inbred Strains 具簡潔獨特性之符號，以英文大寫字母或字母連結數字 表示 based on coat color DBA (Dilute Brown nonAgouti, first inbred mouse ) based on origin NZW (New Zealand White) based on phenotype NOD (Non-Obese Diabetic) others BALB/c, C57BL, 129
Standard Abbreviations AbbreviationStrainAbbreviationStrain 129P129P3/JLC57L/J 129S129S1/SvImJCBACaCBA/CaGnLe AHeA/HeJCBCBA AA/JC3C3H/HeJ AKAKR/JC3FeC3HeB/FeJ CByBALB/cByJD1DBA/1J CBALB/cJD2DBA/2J BC57BLNZBNZB/BlNJ B6C57BL/6JNZWNZW/LacJ B10C57BL/10JSJL or JSJL/J BRC57BR/cdJSWSWR/J
A Laboratory Code The Institute for Laboratory Animal Research (ILAR) maintains the International Laboratory Code Registry (Lab Codes). The purpose of this database is to accurately identify at which laboratory or institution a strain of animals was bred and maintained. Environmental factors can affect the characteristics of a strain, it is important to document where a strain originated J ： The Jackson Laboratory N ： National Institutes of Health Crl ： Charles River Laboratories Rik ： The Institute of Physical and Chemical Research (RIKEN) Narl ： National Applied Research Laboratories Narl ： National Applied Research Laboratories ( 國家實驗研究院 國家實驗動物中心 ) C57BL/6JNarl
由於遺傳的變異隨時間的演進而出現，故實驗 室編碼 (Lab Code) 應隨品系的轉移而累加於後 C57BL = parent strain designation 6JOlaHsdEi = substrain designation 6 = line number J = laboratory code Ola = laboratory code Hsd = laboratory code Ei = Laboratory code Nomenclature of Inbred Substrains Nomenclature of Inbred Substrains (continued) C57BL/6JOlaHsdEi
Nomenclature of Congenic Inbred Strains R1 ES cell (129X1/SvJ x 129S1/Sv) B6.Cg-Apoa1 tm1Unc /J
Nomenclature for Targeted Mutations 以 tm 代表 targeted mutation Serial number : 來自於實驗室原始編號 Lab Code : 突變株所來自之實驗室 129X1-Cftr tm1Unc the first targeted mutation of the cystic fibrosis transmembrane regulator (Cftr) gene at 129X1, produced at the University of North Carolina knock-out 129X1-En1 tm1(Otx2)Wrst the coding region of En1 was replaced by the Otx2 gene, originating from the W. Wurst laboratory knock-in 品系 (/ 旁系 ) ▬基因 tm[serial number][Lab Code] B6.Cg-Apoa1 tm1Unc /J
Figure 1.1. A small metal ear punch can be used to mark the ears of mice at specific locations to create a numerical code for individual mouse identification. 小鼠編號方式
Figure 1.2. Dorsal view of a mouse showing commonly used numerical code approach for ear notching.
Figure 1.3. Ventral view of a mouse to orient feet. Digits can be amputated on neonatal mice as a form of numbering individuals.
Figure 1.4. Tattoo ink can be injected into the skin at specific locations, as indicated, in neonatal mouse feet to create a numerical code to identify individuals.