Genetic diversity derived from pedigree information and estimation of genetic parameters for reproductive traits of Limousine and Charolais cattle raised in Italy

Figures & data

Table 1. Estimates of genetic parameters for reproductive traits in Limousine and Charolais cattle raised in Italy.

	Charolais				Limousine
Age at first calving
Mean	σ²a		σ² r	h^2	σ²a	σ² r	h^2
	21,470		45,290	0.32	10,730	33,200	0.24
Calving intervals
Mean	σ²a	σ²ep	σ² r	h^2	σ²a	σ²ep	σ² r	h^2
	304.60	142.20	11,920.00	0.02	268.10	256.80	9233.00	0.03

σ²a: component of the direct genetic additive variance; σ²ep: component of permanent environmental variance; σ²r: residual variance; h² heritability.

Figure 1. Phenotypic trends for age at first calving (A) and calving intervals (B) in Limousine and Charolais cattle raised in Italy.

Figure 2. Genetic trends for age at first calving (A) and calving interval (B) in Limousine and Charolais cattle raised in Italy.

Figure 3. Number of breeders, average number of calves per breeder and effective size, at intervals of 6 years, from 1960 to 2013 for Charolais (A) and Limousine (B) cattle raised in Italy. N_e: effective size.

Table 2. Classification of registered herds of Limousine and Charolais cattle raised in Italy, according to the use and origin of bulls.

Type of herd	Limousine					Charolais
	UEB	UOB	SB	NH	PEB	UEB	UOB	SB	NH	PEB
Nucleus	No	Yes	Yes	0	0	No	Yes	Yes	0	0
Multiplier	Yes	Yes	Yes	794	53.18%	Yes	Yes	Yes	218	55.45%
Multiplier	Yes	No	Yes	81	100%	Yes	No	Yes	17	100%
Commercial	Yes	Yes	No	566	54.66%	Yes	Yes	No	198	50.77%
Commercial	Yes	No	No	718	100%	Yes	No	No	362	100%
Isolated	No	Yes	No	0	0	No	Yes	No	0	0

UEB: use external bulls; UOB: use own bulls; SB: sell bulls; NH: number of herds; PEB: percentage of external bulls.

Figure 4. Percentage of ancestors known in the first ten generations in the herd of Limousine and Charolais.

Table 3. Population parameters of Limousine and Charolais cattle raised in Italy.

Population parameters	Number of animals
	Limousine	Charolais
Total population	321,286	96,840
Effective population size of founders	1549.36	2191.43
Inbreeding prediction due to the imbalance of the founder contribution	0.03%	0.02%
Number of ancestors contributing to the reference population	33,942	12,251
Number of founder animals with one or more unknown parents	56,430	24,775
Equivalent number of founder animals (one unknown parent)	50,951.50	22,011.00
Number of animals within the reference population	264,856	72,065

Table 4. Average number of traced generations (ANTG), inbreeding increase (ΔF) and effective size (N_e) by generation type in Charolais and Limousine cattle.

Generation types	Limousine			Charolais
	ANTG	ΔF, %	Ne	ANTG	ΔF, %	Ne
Complete^a	1.79	0.47	105.97	1.51	0.85	59.14
Maximum^b	5.82	0.14	355.97	6.32	0.15	329.75
Equivalent^c	3.07	0.38	132.64	2.78	0.55	91.60

^aThe farthest generation, in which all ancestors are known. ^bNumber of generations separating an individual from its earliest ancestor. ^cSum of the terms (1/2)ⁿ of all known ancestors, where n is the generation number that separates an individual from each known ancestor.

Table 5. Average inbreeding coefficient (F%), percentage of inbred individuals (Inb%), mean F for inbred animals (FInb%), mean ratio coefficient (AR%) and effective size (N_e).

Gen.	Limousine						Charolais
	n	F%	Inb%	FInb%	AR%	Ne	n	F%	Inb%	FInb%	AR%	Ne
Average inbreeding by complete generation
0	56,430	0.00	0.00	0.00	0.01		24,775	0.00	0.00	0.00	0.02
1	90,596	0.06	0.91	6.77	0.16	813.40	29,099	0.09	1.28	6.97	0.18	559.60
2	66,865	1.27	23.58	5.37	0.25	41.50	18,644	1.69	25.40	6.67	0.28	31.10
3	80,750	1.14	29.21	3.89	0.28		18,286	1.88	36.68	5.13	0.34	262.20
4	25,579	1.69	55.42	3.05	0.34	116.80	5509	3.43	72.46	4.73	0.41	31.70
5	1064	3.70	86.47	4.28	0.40	24.30	527	7.56	92.98	8.13	0.46	11.60

n: number of individuals. Gen.: generation.