Efficacy of repeated ovum pick-up in Podolic cattle for preservation strategies: a pilot study

Figures & data

Figure 1. Schedule used prior to OPU in order to carry out oocyte retrieval with and without eCG.

PGF2(α): Prostaglandin F2-α; GnRH: gonadotropin-releasing hormone; OPU: Ovum Pick-Up; eCG: Equine chorionic gonadotropin.

Table 1. Environmental parameters recorded during the trial conducted in Calabria (Italy), mean values ± standard deviation for summer and autumn (paired-t test).

	Season
	Summer	Autumn
Average Temperature (°C)	26.1 ± 1.0^a	21.6 ± 2.3^b
Minimal Temperature (°C)	21.6 ± 2.4	18.9 ± 2.6
Maximal Temperature (°C)	28.4 ± 0.3	23.7 ± 2.0
Humidity (%)	52.7 ± 0.8^A	69.5 ± 1.3^B
Average wind speed (Km/h)	17.4 ± 1.5	16.3 ± 1.3
Maximal wind speed (Km/h)	26.3 ± 1.6	24.0 ± 1.3

^A,BValues with different superscripts are significantly different; p < .01.

^a,bValues with different superscripts are significantly different; p < .05.

Table 2. Individual variability in the number of total follicles, total COCs, superior quality COCs, i.e. Grade 1 + 2 COCs and blastocysts among Podolic cattle.

Animals	Tot. follicles (N.)	Tot. COCs (N.)	Grade 1 + 2 COC (N.)	Blastocysts (N.)
	Mean ± SE	Mean ± SE	Mean ± SE	Mean ± SE
1	2.9 ± 0.4	0.5 ± 0.2	0.5 ± 0.2	0.3 ± 0.3
2	3.4 ± 0.7	1.0 ± 0.3	0.6 ± 0.3	0.8 ± 0.6
3	3.6 ± 0.5	1.4 ± 0.6	1.1 ± 0.6	0.8 ± 0.3
4	3.9 ± 0.6	1.3 ± 0.3	0.8 ± 0.3	0.5 ± 0.2
5	4.4 ± 0.6	2.1 ± 0.5	1.1 ± 0.4	0.4 ± 0.3
6	4.5 ± 0.6	3.0 ± 0.6	1.1 ± 0.5	0.4 ± 0.2
7	4.6 ± 0.5	3.0 ± 0.6	2.2 ± 0.6	0.8 ± 0.4
8	4.6 ± 1.1	3.1 ± 1.2	2.3 ± 0.9	1.5 ± 0.7
9	5.4 ± 0.8	2.3 ± 0.6	1.4 ± 0.5	1.0 ± 0.5
10	5.4 ± 0.8	3.2 ± 1	1.4 ± 0.4	0.9 ± 0.3
11	5.6 ± 0.7	2.5 ± 0.6	1.5 ± 0.3	1.4 ± 0.4
12	5.6 ± 0.9	3.1 ± 0.9	2.1 ± 0.7	0.8 ± 0.2
13	6.1 ± 1.0	2.4 ± 0.6	1.4 ± 0.4	0.9 ± 0.5
14	7.0 ± 1.1	3.0 ± 0.9	1.9 ± 0.7	1.2 ± 0.3
15	7.8 ± 1.1	4.6 ± 1.2	1.8 ± 0.6	0.7 ± 0.3
16	7.9 ± 1.5	5.2 ± 1.6	2.8 ± 1.0	0.6 ± 0.4
17	7.9 ± 1.2	2.8 ± 1.2	1.5 ± 0.8	0.2 ± 0.2
18	8.3 ± 1.4	6.8 ± 1.8	4.0 ± 1.2	2.7 ± 1.0

COCs: cumulus-enclosed oocytes.

Table 3. Effect of eCG priming on follicular population, oocyte recovery and embryo yields in Podolic cattle subjected to OPU.

	OPU groups
	non eCG-treated	eCG-treated
Large follicles N.	0.70 ± 0.10	0.50 ± 0.10
Medium follicles N.	0.90 ± 0.18^a	1.70 ± 0.20^b
Small follicles N.	3.40 ± 0.40	3.80 ± 0.30
Total follicles N.	5.00 ± 0.30	6.00 ± 0.30
Total COCs N.	3.40 ± 0.40^A	2.30 ± 0.30^B
Grade 1 + 2 COCs N. (%)	1.90 ± 0.30 54.40 ± 4.30	1.40 ± 0.20 62.90 ± 4.70
Grade 1 + 2+3 COCs N. (%)	2.70 ± 0.30^a79.30 ± 3.60	1.90 ± 0.20^b89.10 ± 2.30
Recovery (%)	60.50 ± 4.00^A	38.30 ± 3.50^B
Cleaved N. (%)	1.70 ± 0.20 49.40 ± 5.40^a	1.70 ± 0.20 72.90 ± 5.70^b
Blastocysts N. (%)	0.90 ± 0.20 23.00 ± 4.20^x	0.90 ± 0.10 41.10 ± 5.70^y

Values are expressed as means ± SE.

^A,BValues with different superscripts are significantly different; p < .01.

^a,bValues with different superscripts are significantly different; p < .05.

^x,yValues with different superscripts are significantly different; p = .054.

OPU: Ovum Pick-Up; eCG: Equine chorionic gonadotropin; COCs: cumulus-enclosed oocytes.

Table 4. Effect of season on follicular population, oocyte recovery and embryo yields in Podolic cattle undergone OPU.

	Seasons
	Summer	Autumn
Large follicles N.	0.6 ± 0.1	0.6 ± 0.1
Medium follicles N.	1.7 ± 0.2^A	0.9 ± 0.1^B
Small follicles N.	3.2 ± 0.4^a	4.0 ± 0.3^b
Total follicles N.	5.5 ± 0.3	5.5 ± 0.3
Total COCs N.	2.6 ± 0.3^a	3.1 ± 0.4^a
Grade 1 + 2 COCs N. (%)	1.5 ± 0.2^a57.5 ± 4.7	1.8 ± 0.2^b59.5 ± 4.3
Grade 1 + 2+3 COCs N. (%)	2.1 ± 0.3^a84.3 ± 3.1	2.5 ± 0.3^b83.8 ± 3.1
Recovery (%)	46.5 ± 3.4	52.5 ± 4.4
Cleaved N. (%)	1.5 ± 0.2 65.0 ± 5.9	1.9 ± 0.2 56.7 ± 5.4
Blastocysts N. (%)	0.8 ± 0.2 33.5 ± 5.3	1.0 ± 0.1 30.2 ± 4.9

Values are expressed as means ± SE.

^A,BValues with different superscripts are significantly different; p < .01.

^a,bValues with different superscripts are significantly different; p < .05.

OPU: Ovum Pick-Up; COCs: cumulus-enclosed oocytes.

Table 5. Effect of the interaction treatment (T)*season (S) on follicular population, oocyte recovery and embryo yields in Podolic cattle undergone OPU.

	Seasons
	Summer		Autumn		SE	p Value
	Non eCG	eCG-treated	Non eCG	eCG-treated		T*S	T	S
Large follicles N.	0.639	0.611	0.778	0.444	0.100	.135	.078	.135
Medium follicles N.	1.190	2.190	0.690	1.110	0.100	.162	<.001	<.001
Small follicles N.	2.970	3.330	3.720	4.250	0.300	.862	.355	.084
Total follicles N.	4.810	6.140	5.190	5.810	0.300	.456	.046	.954
Total COCs N.	2.970	2.220	3.830	2.360	0.300	.445	.020	.290
Grade 1 + 2 COCs N.	1.610	1.330	2.110	1.470	0.200	.562	.142	.565
Grade 1 + 2 COCs (%)	51.560	63.710	57.410	61.990	6.300	.555	.181	.755
Grade 1 + 2+3 COCs N.	2.390	1.830	2.970	2.000	0.300	.572	.040	.310
Grade 1 + 2+3 COCs (%)	80.460	88.220	78.110	90.220	4.500	.620	.027	.904
Recovery (%)	62.530	38.830	73.890	53.140	4.600	.758	<.001	.005
Cleaved N.	1.450	4.460	2.000	1.810	0.200	.750	.854	.160
Cleaved (%)	50.720	72.500	44.600	67.810	6.900	.920	.002	.447
Blastocysts N.	0.810	0.810	1.150	0.960	0.200	.700	.783	.334
Blastocysts (%)	26.250	40.520	19.490	41.800	7.100	.575	.012	.649

OPU: Ovum Pick-Up; eCG: Equine chorionic gonadotropin; COCs: cumulus-enclosed oocytes; T: treatment; S: season; T*S: interaction treatment*season.

Values are expressed as means ± SE.

Table 6. Effect of OPU on haematological parameters.

Parameters	Groups		p Value	Reference value*
	TG (OPU) n = 18	CG (no OPU) n = 8
	Mean ± SE	Mean ± SE
Haptoglobin (mg/mL)	0.0300 ± 0.0100	0.0300 ± 0.0100	.9694	0.0220–0.0470
Direct Bilirubin (mg/dL)	0.0400 ± 0.0100	0.0300 ± 0.0100	.4435	0.0400–0.4400
Total bilirubin (mg/dL)	0.3900 ± 0.0100	0.3500 ± 0.0200	.0916	0.0100–0.5000
Cholesterol (mg/dL)	115.9900 ± 4.5100	107.7500 ± 7.2300	.3377	97–145
Creatinine (mg/dL)	1.8900 ± 0.0400	1.8800 ± 0.5900	.9650	1–2
GGT (U/L)	14.1500 ± 1.0300	11.5000 ± 1.6500	.1793	10–27
GOT (U/L)	66.0800 ± 2.0200	59.2500 ± 3.2400	.0781	78–132
GPT (U/L)	53.3100 ± 2.3400	48.8200 ± 3.7600	.3137	11–40
Triglycerides (mg/dL)	26.1000 ± 1.1800	26.1000 ± 1.8900	.8081	0–14
Urea (mg/dL)	20.3400 ± 0.5800	19.0300 ± 0.9400	.2423	6–27
Albumine (g/dL)	3.1900 ± 0.1100	3.5300 ± 0.1800	.1150	2.5000–3.8000
Alfa (g/dL)	1.0600 ± 0.0300	0.9900 ± 0.0500	.1945	0.7500–1.0000
Beta (g/dL)	0.4600 ± 0.0100	0.4800 ± 0.0200	.6910	0.8000–1.1200
Gamma (g/dL)	2.2900 ± 0.0600	2.1400 ± 0.0900	.1868	1.6900–2.2500
Alb/Glob	0.8600 ± 0.0400	1.0500 ± 0.0700	.0553	0.8500–0.9500
Tot. proteins (g/dL)	7.0100 ± 0.1100	7.1400 ± 0.1800	.5385	6.7000–7.6000

Comparison between cattle that underwent OPU and control cattle handled exactly in the same manner, except for the OPU procedure.

*Laboratory reference values.

OPU: Ovum Pick-Up.