Status as of: 2016-04-08

DESCRIPTION OF NATIONAL GENETIC EVALUATION SYSTEMS

Country (or countries)	ITALY	
Main trait group1
NOTE! Only one trait group per form!	CALVING TRAITS	
Breed(s)	Holstein	
Trait definition(s) and unit(s) of measurement2
Attach an appendix if needed	Calving difficulty scored on a 5 classes scale
A – easy calving
B – Calved with the assistance of one person
C – Cesarean birth
D – Difficult calving
E – Embriotomy	
Method of measuring and collecting data	Milk recording people do collect records scored by the farmers at calving	
Time period for data inclusion	From 1987	
Age groups (e.g. parities) included	All parities	
Other criteria (data edits) for inclusion of records	Herds with more than 92% of scores for one class only in one year are discarded.	
Criteria for extension of records (if applicable)		
Sire categories	All (A.I. and non A.I, national and foreign)	
Environmental effects3, pre-adjustments 	None	
Method (model) of genetic evaluation3	Structural heteroskedastic threshold model  with direct and maternal effects	
Environmental effects3 in the genetic evaluation model	Sex of calf x age at calving x parity (F)
Year x month (F)
Province x year (F)
Herd-year (R)	
Adjustment for heterogeneous variance in evaluation model	Yes heterogeneity of residual variances described on a log scale with the effect of:
-	province
-	year
-	sex
-	month
-	parity	
Use of genetic groups and relationships	Sire of calf, sire of dam (both with relationship matrix)
No genetic groups	
Blending of foreign/Interbull information in evaluation	No	
Genetic parameters in the evaluation	See Appendix GE for heritability/genetic variance estimates
Use also appendices PR, CO, BCO, SM, as applicable, if you participate in the international genetic evaluations of Interbull	
System validation	Method  3	
Expression of genetic evaluations
If standardised (e.g. RBV), give standardisation formula in the appendix	RBV positive values means more easy calvings. Average is 100 SD is 5	
Definition of genetic reference base
Next base change	Bull born between 1989 and 1998. Rolling base cows born 2008-2010

August 2017	
Calculation of reliability	1-PEV/2g where PEF is obtained as the diagonal element of the inverse of the coefficient matrix for a simplified threshold model with Sire, MGS, sex*parity*age, month*year, province*year	
Criteria for official publication of evaluations	Minimum 50% reliability	
Number of evaluations / publications per year	2	
Use in total merit index4	No	
Anticipated changes in the near future		
Key reference on methodology applied	J.L. Foulley, D. Gianola. 1996. Statistical analysis of ordered categoricak data via a structural heteroskedastic threshold model. Genet. Sele. Evol. 28:249-273.
E. Manfredi, V. Ducrocq, J.L. Foulley. 1991. Genetic analysis of dystocia in cattle. J. Dairy Sci., 74: 1715-1723.
Ducrocq V., 2000. Calving ease evaluation of French dairy bulls with a heteroskedastic threshold model with direct and maternal effects. Interbull bulletin 25: 123- 130.
	
Key organization: name, address, phone, fax, e-mail, web site	ANAFI
Via Bergamo, 292
26100 CREMONA
ITALY
Phone:  +39-0372-4741
Fax:      +39-0372-474203
e-mail: ricercasvil@anafi.it
web site: www.anafi.it 	
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).

 
Parameters for national genetic evaluations for calving traits as provided to Interbull

Country (or countries):	ITALY	
Main trait group:	Calving Traits	
Breed(s):	HOLSTEIN	

Trait	h2	genetic
variance	official proof
standardisation formulaa	
Direct calving ease:
	0.08	0.03621	StandEval=(-(eval/0.09)*5)+100.	
Maternal calving ease:
	0.036	0.01231	StandEval=(-((eval+0.02)/0.05)*5)+100.	
Direct stillbirth:
				
Maternal stillbirth:
				
a	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.