**16. Conclusion**

ferences between individual boars may be responsible for freezability and post-thaw quality

Cervical AI with FT semen usually results in suboptimal fertility; thereby, deep AI using IUI and DIUI procedures was developed. We evaluated fertility (fertilization rate, FR and LS) of

spontaneously ovulating weaned sows. The results revealed that at approximately 2 days following inseminations either with IUI or DIUI, embryo(s) could be recovered from both sides of the oviducts. This observation, the first report in FT semen [99], was consistent with previous studies where the extended fresh semen was used [85,100,101]. It was demonstrat‐ ed that both transuterine and transperitoneal migrations were involved in transport of sperm inseminated using DIUI to reach the other side of the oviduct [85]. Nonetheless, com‐ paring between techniques, fertilization rate in the IUI group was significantly higher than the DIUI group. The reason for this finding might not associate with the insemination tech‐ niques, but rather it was a result of insemination time relative to the moment of ovulation

After AI using the same procedures (IUI and DIUI) and same numbers of FT sperm (1 to 2

 per dose), acceptable fertility (67% FR and 7.7 to 10.5 LS) were obtained in both groups (P>0.05); however, TB in the DIUI group was about 3 piglets fewer than the IUI group. This was probably the consequence of inadequate numbers of functional sperm used for DIUI

motile sperm) which leaded to the unilateral and/or incomplete bilateral fertiliza‐

which was not appropriate in the DIUI group (≥ 8 h before ovulation).

No. of sows 9 9

Parity number (mean±SD) 5.0±1.9 4.8±1.9

Weaning to estrus interval (days) (mean±SD) 4.9±0.9 5.1±1.5

Sows inseminated within 6 h before/after ovulation (%) 8/9 (89) 9/9 (100)

Non-return rate at 24 days (%) 8/9 (89) 6/9 (67)

Farrowing rate (%) 6/9 (67) 6/9 (67)

Number of total piglets born per litter (mean±SD) 10.5±2.9 7.7±3.0

Number of piglets born alive per litter (mean±SD) 9.5±3.0 7.5±3.0

**Table 2.** Non-return rate, farrowing rate, number of total piglets born per litter and number of piglets born alive per litter after intra-uterine insemination (IUI) and deep intra-uterine insemination (DIUI) with frozen-thawed boar semen

Sows return-to-estrus after 24 days (%) 2/8 (25) 0 (0)

total sperm per dose, and DIUI, with 1x109 per dose, in

**Insemination procedure IUI DIUI**

of their sperm [55].

x109

[102]

(400x106

FT boar semen after IUI, with 2x109

28 Success in Artificial Insemination - Quality of Semen and Diagnostics Employed

tion and resulted in the low LS [102] (Table 2)

The feed supplement containing the rich of PUFAs, vitamins and minerals can improve the sperm motility, vitality and number of sperm per ejaculation in boar. The success of feed supplement depends on the initial performance of the boar. They may not improve the se‐ men quality if the boars are the good performance of semen producers. Moreover, taking all of our researches, we can conclude that the production of cryopreserved boar semen and AI with FT boar semen could be successfully performed in Thailand and its application in com‐ mercial farm is undergoing. An IUI procedure was considered to be suitable for FT boar se‐ men to produce acceptable fertility rates. This is very useful for the conservation and/or production of animal with high genetic merits.
