Status as of: 2020-10-01

Form GE

DESCRIPTION OF NATIONAL GENETIC EVALUATION SYSTEMS

Country (or countries)	ZAF	
Main trait group	Longevity	
Breed(s)	Holstein	
Trait definition(s) and unit(s) of measurement2
Attach an appendix if needed	Differences in functional herd life of daughters over defined periods.	
Method of measuring and collecting data	Lactation data obtained from milk recording is used to determine survival over defined periods.	
Time period for data inclusion	Lactation records since 1975.	
Age groups (e.g. parities) included	Survival up to fourth calving.	
Other criteria (data edits) for inclusion of records	Only cows with first lactations are included.  At least one parent should be known. Data after calving intervals shorter than 210 days, is discarded. Age restrictions : Parity 1 : 20-42 months, Parity 2 : 30-54 months, Parity 3 : 40-67 months and Parity 4 : 50-83 months.	
Criteria for extension of records (if applicable)	N.a.	
Sire categories	All domestic and foreign AI sires with daughter information, as well as natural service herd sires included.	
Environmental effects3, pre-adjustments 	None	
Method (model) of genetic evaluation3	MT -  BLUP – AM
Survival traits : Survival up to 120 dim first lactation
Survival up to 240 dim first lactation
Survival up to second calving
Survival up to third calving
Survival up to fourth calving
	
Environmental effects3 in the genetic evaluation model	Fixed : Herd x Year of calving; rhs = registration status (stud / grade) x herd size change (4 classes) x season of calving (6); linear and quadratic regressions of age at first calving; linear, quadratic and cubic regressions of standardized rank of protein yield within herd-year of first calving;  linear, quadratic and cubic regressions of standardized rank of butterfat yield within herd-year of first calving; standardized rank of protein yield within herd-year of first calving x rhs	
Adjustment for heterogeneous variance in evaluation model	None	
Use of genetic groups and relationships	Unknown parents are grouped together 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. Trend validation based on Interbull method II, correlations between successive runs.	
Expression of genetic evaluations
If standardised (e.g. RBV), give standardisation formula in the appendix	RBV with mean 100 (average of base cows) and SD of 12. (EBVs from the different survival periods are standardized and combined using weighting factors 0.1*HL1 + 0.15*HL2 + 0.2*HL3 + 0.25*HL4 + 0.3*HL5)	
Definition of genetic reference base
Next base change	Cows born in 2015

2025 to 2020	
Calculation of reliability	PEVs	
Criteria for official publication of evaluations	Cows should have a first lactation. Sires should have 20 daughters in 10 herds.	
Number of evaluations / publications per year	Three evaluations : Feb, June and Oct	
Use in total merit index4	HSI = 0.17 BF(kg) + 0.21 Prot(kg) + 0.08 Efficiency + 0.08 Conformation – 0.01 ANG + 0.11 Udder + 0.06 F&L + 0.10 Herd Life – 0.05 SCS – 0.13 ICP	
Anticipated changes in the near future	None	
Key reference on methodology applied	Sewalem, A. et al., 2007. JDS 90, 2025-2028.
Lidauer et al., 2015. Technical Reference Guides for Mix99.	
Key organisation: name, address, phone, fax, e-mail, web site	SA Studbook 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 LO

Parameters used in genetic evaluation

Country (or countries):	South Africa	
Main trait group:	Longevity	
Breed (repeat as necessary):	Holstein	

Trait	   Definition	ITBa	    H2b	genetic
varianceb	official proof
standardisation formulac	
Direct Longevity	Functional Herd Life	X           0.032	       0.00314 	
			 		RBV=((EBV-a)/b)*c+d
a=mean EBV of base cows
b=SD of EBVs of base cows
SD  = 12
d = 100	
Survival 1	Survival up to 120 dim in 1st lactation		0.046	0.00076		
Survival 2	Survival up to 240 dim in 1st lactation		0.034	0.00113		
Survival 3	
Survival up to 120 dim in 1st lactation	
	
0.005	
0.000074	

	Survival up to 2nd calving		0.024	0.00387		
Survival 4	
Survival up to 120 dim in 1st lactation	
	
0.005	
0.000074	

	Survival up to 3rd calving		0.030	0.00588		
Survival 5	Survival up to 5th
Calving		0.024	0.00408		

						

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.

Direct Herd Life Ratios

	HL1	HL2	HL3	HL4	HL5	
HL1	0.046
	0.913
	0.247
	-0.129
	0.039
	
HL2		0.034
	0.236
	-0.066
	0.106
	
HL3			0.024
	0.690
	0.544
	
HL4				0.030
	0.910
	
HL5					0.024