Status as of: 2020-09-01

Form GE

DESCRIPTION OF NATIONAL GENETIC EVALUATION SYSTEMS

Country (or countries)	RSA	
Main trait group1
NOTE! Only one trait group per form!	FEMALE FERTILITY	
Breed(s)	JERSEY	
Trait definition(s) and unit(s) of measurement2
Attach an appendix if needed	Calving Interval (days)	
Method of measuring and collecting data	Interval between calvings (lactations 1 – 4) obtained from
Milk Recording data	
Time period for data inclusion	All parities since 1970 + all available pedigree information 	
Age groups (e.g. parities) included	Parity 1 - 4	
Other criteria (data edits) for inclusion of records	Age restrictions within parity, only calving intervals within 300 – 700 days included, cows still milking in current lactation  are censored for that lactation	
Criteria for extension of records (if applicable)	NA	
Sire categories	All bulls with progeny information including domestic and foreign AI sires, natural service herd sires 	
Environmental effects3, pre-adjustments 	Penalization incorporated for cows with extended calving intervals without a following calving date	
Method (model) of genetic evaluation3	Multi-trait (CI1, CI2, CI3, Milk Yield, Dairy Strength, Thurl Width and Rear Udder Height)	
Environmental effects3 in the genetic evaluation model	Age at calving, herd-year-season (F), animal (R)	
Adjustment for heterogeneous variance in evaluation model	None	
Use of genetic groups and relationships	Phantom parent groups defined according to country, birth year and selection path (4 paths).	
Blending of foreign/Interbull information in evaluation	MACE EBVs are blended with national EBVs until reliability based on SA daughters are 80%.	
Genetic parameters in the evaluation	See appendix	
System validation	Data checks and validations on quality before genetic evaluation based on outlier detection, duplicates and pedigree checks. Verification of genetic trend and correlation of proofs post-evaluation.	
Expression of genetic evaluations
If standardised (e.g. RBV), give standardisation formula in the appendix	Individual parity EBVs are combined to overall CI (days) with weights of 0.44, 0.33 and 0.23 for parity 1, 2 and 3 respectively.	
Definition of genetic reference base
Next base change	Cows born in 2015

2025 to Cows born in 2020	
Calculation of reliability	PEVs	
Criteria for official publication of evaluations	Cows should be measured. Sires should have 20 daughters in 10 herds.	
Number of evaluations / publications per year	Three : Feb; May and September	
Use in total merit index4	SAINET = (0.40*Prod) + (0.20*Functional Type) + (0.10*Functional Udder)  + (0.20 * Fertility) + (0.10 * Longevity)	
Anticipated changes in the near future	-	
Key reference on methodology applied	Biffani, S., Marusi, M., Biscarini, F. & Canavesi, F., 2005. Developing a genetic evaluation for fertility using angularity and milk yield as correlated traits. Interbull Bulletin 33, 63-66.

Gonzalez-Recio, O. & Alenda, R., 2005. Genetic parameters for female fertility traits and a fertility index in Spanish dairy cattle. J. Dairy Sci. 88, 3282-3289.

Olori, V.E., Pool, M.H., Calus, M.P.L., Cromie, A.R. & Veerkamp, R.F., 2003.  Joint evaluation of survival and fertility in dairy cattle with a linear model. Interbull Bulletin 30, 20-24.

Lidauer et al., 2015. Technical Reference Guides for Mix99
	
Key organisation: name, address, phone, fax, e-mail, web site	SA Stud Book and Livestock Improvement Association
PO Box 270, Bloemfontein, South Africa, 9300
Tel : +27-51-4100900 Fax : +27-51-4473964
Japie@studbook.co.za      Bernice@studbook.co.za
http://www.studbook.co.za	
1) Either: Production (e.g. milk, fat, protein), Conformation, Health (e.g. mastitis resistance, milk somatic cell, resistance to diseases other than mastitis), Longevity, Calving (e.g. stillbirth, calving ease), Female fertility (e.g. non-return rate, interval between reproductive events, number of AI’s, heat strength), Workability (e.g. milking speed, temperament), Beef production, Efficiency (e.g. body weight, energy balance, body conditioning score), or Other traits.
2) Indicate frequencies per category if the trait is categorical and specify transformation of data if practiced.
3) Use abbreviations for most common effects (see document with list of abbreviations at http://www-interbull.slu.se/service_documentation/General/list_of_abbreviations.rtf) and indicate random (R) or fixed (F).
4) Please give economic weights and indicate how they are expressed (preferably in genetic standard deviation units).

Form GE	Appendix GE

Parameters used in genetic evaluation

Country (or countries):	RSA	
Main trait group:	Female Fertility	
Breed (repeat as necessary):	Jersey	

Trait	Definition	ITBa	h2b	genetic
varianceb	official proof
standardisation formulac	
Calving Interval
(days)	Lac1 – Lac2		0.028	95.79		
	Lac2 – Lac3		0.025	74.62		
	Lac3 – Lac4		0.044
	154.71		
						
Overall Calving Interval (days)	0.44EBVCI1+ 0.33EBVCI2+0.23EBVCI3	X	0.031	102.36		

a	Indicate, with X, traits that are submitted to Interbull for international genetic evaluations.
b	If repeated records are treated as separate traits, provide heritability estimates and genetic variances separately for each trait, as well as for all traits pooled, i.e. for the trait submitted to Interbull.
c	Expressed as follows:
StandEval=((eval-a)/b)*c+d where a=mean of the base adjustment, b=standard deviation of the base, c=standard deviation of expression (include sign if scale is reversed), and d=base of expression.

Genetic parameters in the evaluation 

Direct Ratios

CI1	
CI2	
CI3	
Milk	
DS	
TW	
RUH

CI1	
0.028	
0.951	
0.905	
0.437	
0.547	
0.566	
0.624	

CI2	
	
0.025	
0.948	
0.531	
0.567	
0.415	
0.627	

CI3	

0.044	
0.589	
0.623	
0.608	
0.468	

Milk	

	
0.285	
0.509	
0.472	
0.633	

DS	

	
	
0.074	
0.586	
0.621	

TW	

	

0.046	
0.242	

RUH	

	

	
0.110