Effect of carbetocin administration during the mid-period of parturition on farrowing duration, newborn piglet characteristics, colostrum yield and milk yield in hyperprolific sows.

Control of the farrowing process is crucial to reduce the risk of post-parturient disorders in sows and newborn piglet mortality. Carbetocin is a long-acting oxytocin-like compound that has been introduced to domestic animal obstetrics. The aims of the present study were to evaluate the effects of carbetocin administration during the mid-period of parturition on farrowing duration as well as colostrum and milk production and its side effects on neonatal piglet characteristics in hyperprolific sows. The study included 89 Landrace x Yorkshire crossbred sows and 1534 piglets. Sows were randomly distributed into two groups: CONTROL (n = 46), where sows were allowed to farrow naturally, and TREATMENT (n = 43), where sows were administered 0.5 µg/kg carbetocin intramuscularly after the birth of the 7th piglet. In each litter, the piglets were classified into two groups according to birth order: 1-7 and ≥8. The colostrum yield of sows and the colostrum intake of each individual piglet were calculated. Litter weight gain of the piglets from 3 to 5 days of lactation was used to estimate milk yield. Farrowing duration tended to be reduced from 338.4 ± 35.2 min in the CONTROL group to 255.3 ± 36.4 min in the TREATMENT group (P = 0.105). However, the colostrum yield in the TREATMENT group was lower than that in the CONTROL group (3828 ± 149 and 3041 ± 158 g, respectively, P < 0.001). Nevertheless, milk yield during 3-5 days of lactation in the TREATMENT group did not differ significantly compared to that in the CONTROL group (7.53 ± 0.01 and 7.54 ± 0.01 kg/day, respectively, P = 0.643). The incidence of stillbirths in the TREATMENT group was not significantly different from that in the CONTROL group (8.3 and 7.4%, respectively, P = 0.944). However, the incidence of piglets born with umbilical cord rupture in the TREATMENT group with birth order ≥8 was higher than that in the CONTROL group in the same birth order (16.6 and 5.7%, P < 0.001). Across groups, colostrum intake of piglets born with birth order ≥8 was lower than that of piglets born in the birth orders 1-7 (187.4 ± 8.7 and 241.5 ± 9.0 g, P < 0.001). Interestingly, the colostrum intake of piglets with birth orders 1-7 in the TREATMENT group was also lower than that of piglets with the same birth order in the CONTROL group (214.9 ± 12.9 and 268.1 ± 12.5 g, respectively, P = 0.003). Colostrum intake was lowest in the piglets with birth order ≥8 in the TREATMENT group (159.6 ± 12.3, P < 0.001). Carbetocin administration after the birth of the 7th piglet reduced the birth interval of piglets but increased the incidence of piglets born with umbilical rupture and reduced colostrum intake. Therefore, colostrum supplementation and care of the newborn piglets immediately after birth are strongly recommended after carbetocin administration.

Postpartum prostaglandin F2α administration affects colostrum yield, immunoglobulin G, and piglet performance.

OBJECTIVE: Current study was conducted to determine the effect of postpartum prostaglandin F2α (PGF2α) administration on colostrum and milk yield, colostrum immunoglobulin G (IgG) and piglet growth performance. METHODS: In total, 36 sows were included in the experiment. The sows were classified into two groups: i) control (n = 11) and ii) PGF2α (n = 25). Sows in the PGF2α group received 10 mg of PGF2α within an hour after farrowing. The body weight of piglets was measured at 0 and 24 h after birth to estimate colostrum consumption. Colostrum was collected at 1 and 24 h after farrowing to determine IgG concentrations. For milk yield study, the remaining sows in the PGF2α group (n = 23) were divided into two subgroups: i) single PGF2α (n = 12) and ii) multiple PGF2α (n = 11). In the multiple PGF2α, the sows received repeated doses of PGF2α at seven and 14 days postpartum. The piglets' body weight was measured at 0, 1, 5, and 20 days of age. The milk yield of the sows was calculated. RESULTS: Colostrum yield of sows averaged 5.62±2.25 kg. Sows treated with PGF2α postpartum had a higher colostrum yield than control (7.01 and 5.12 kg, p<0.05). The concentration of IgG in colostrum at 24 h in the PGF2α group was higher than the control (31.6 and 17.4 g/L, p<0.05). For primiparous sows, milk yield was highest in the sows treated with multiple doses of PGF2α during lactation and lowest in control sows (10.25 and 7.61 kg, p<0.05). Colostrum intake was higher in the treatment than the control groups (+56.7 g, p<0.05). Primiparous sows treated with multiple doses of PGF2α had a higher litter weight than controls (p<0.01). CONCLUSION: Postpartum treatment with PGF2α improved colostrum yield and IgG in multiparous sows and increased colostrum intake of piglets. Multiple administration of PGF2α improved the milk yield and increased litter weight of piglets in primiparous sows.

Factors influencing pre-ovulatory follicle diameter and weaning-to-ovulation interval in spontaneously ovulating sows in tropical environment.

Follicle development and timing of ovulation are indicators of the reproductive performance of sows. The present study aimed to determine factors influencing pre-ovulatory follicle diameter and weaning-to-ovulation interval (WOI) in spontaneously ovulating sows in tropical climates with special emphasis on breed, parity and backfat thickness at weaning. In total, 80 sows were included in the study. Follicle development was determined by using transrectal real-time B-mode ultrasonography every 6 hr after standing oestrus. Weaning-to-oestrous interval (WEI), oestrous-to-ovulation interval (EOI), WOI and the diameter of graafian follicles were investigated in relation to breed, parity number (1, 2-3 and 4-7) and backfat thickness (low, moderate and high) of sows. Overall, WEI, EOI, WOI and the pre-ovulatory follicle diameter were 92.5 ± 21.6 hr, 64.3 ± 19.3 hr, 156.3 ± 29.1 hr and 10.3 ± 2.0 mm, respectively. Pre-ovulatory follicle size was smaller in primiparous sows compared with sows of greater parity, 4-7 (9.7 ± 0.51 and 11.7 ± 0.52 mm, respectively, p < .05). Weaning-to-ovulation interval was positively correlated with WEI (r = 0.75, p < .001) and EOI (r = 0.66, p < .001), but negatively correlated with size of the graafian follicle (r = -0.34, p < .01). Sows with a shorter WEI had a larger pre-ovulatory follicle diameter (at 64 hr after oestrus) (r = -0.37, p < .01). Sows with low backfat thickness had a WOI 23.4 hr longer than those with moderate backfat thickness (p < .05) and 17.6 hr longer than sows with a high backfat thickness (p = .140). The follicle diameter in primiparous sows with high backfat thickness (11.7 ± 1.1 mm) was higher than in those with low (8.9 ± 0.7 mm, p < .05) or moderate (8.6 ± 0.8, p < .05) backfat thickness. In conclusion, factors influencing follicle diameter and WOI in sows included parity number and backfat thickness at weaning. The impact of backfat thickness on follicle diameter, WEI and WOI was most pronounced in primiparous sows.

Reproductive performance of weaned sows after single fixed-time artificial insemination under a tropical climate: Influences of season and insemination technique.

We evaluated the reproductive performance of sows after single fixed-time AI under a tropical climate and investigated the influences of season and insemination technique on the efficacy of single fixed-time AI. After weaning, the sows were divided into CONTROL (n = 212) and FIXED-TIME (n = 212) groups. Sows in the CONTROL group were inseminated at 12 and 36 h after the onset of oestrus, while sows in the FIXED-TIME group were administered 10 µg of GnRH at 72 h after weaning and were inseminated 32 h later. Reproductive performance parameters, including total born, born alive, mummified foetuses and stillborn piglets per litter, piglet birth weight, variation of piglet birth weight within litter, regular return-to-oestrus and farrowing rate, were compared between the two groups. Season was classified into two groups: cool (n = 170) and hot (n = 254), and insemination technique was classified into two groups: conventional AI (n = 171) and intra-uterine insemination (IUI) with a reduced number of spermatozoa (n = 253). On average, regular return-to-oestrus (3.3 vs. 5.6%, P > 0.05) and farrowing rates (92.8 vs. 88.1%, P > 0.05) did not differ between CONTROL and FIXED-TIME groups. However, the total born and born alive piglets per litter in the FIXED-TIME were lower than in the CONTROL group (12.0 vs. 12.8 piglets/litter; P = 0.030 and 11.3 vs. 12.2 piglets/litter, P = 0.007). Interestingly, the number of total born piglets in the FIXED-TIME group was lower than in the CONTROL group only in the sows inseminated in the hot season (11.7 ±â€¯0.32 and 12.9 ±â€¯0.31, respectively, P = 0.005). Piglet birth weight, variation of piglet birth weight within litter, number of piglets at weaning and body weight of piglets at weaning did not differ between groups, irrespective of the season (P > 0.05). The total number of piglets born per litter in the FIXED-TIME group was lower than that in the CONTROL group in sows inseminated via IUI (11.7 ±â€¯0.32 and 12.9 ±â€¯0.32, respectively, P = 0.013), but not in sows inseminated using conventional AI (12.7 ±â€¯0.42 and 12.5 ±â€¯0.41, respectively, P = 0.772). Single fixed-time AI could be successfully performed in sows under a tropical climate, with a promising reproductive performance. However, a decreased litter size at birth after single fixed-time AI was observed when insemination was performed in the hot season. Moreover, single fixed-time AI using IUI with a reduced number of spermatozoa also decreased litter size at birth.

Factors affecting estrus and ovulation time in weaned sows with induced ovulation by GnRH administration in different seasons.

Follicle development in post-weaning sows is influenced by various factors. To control ovulation time using hormone, factors that influence ovulation should be investigated. The present study was performed to evaluate the effect of GnRH (buserelin) administration in relation to season and sow parameters on ovulation time in weaned sows. Seventy-seven weaned sows were divided into the following groups: control (hot season, n=21; cool season, n=16) and treatment (hot season, n=22; cool season, n=18). Sows were kept in a close house equipped with an evaporative cooling system. Ovulation time was determined every 6 hr using transrectal ultrasonography. Administration of 10 µg buserelin at 72 hr after weaning affected estrus-to-ovulation interval (EOI) and weaning-to-ovulation interval (WOI) in sows (P<0.05). The percentage of sows that ovulated between 44-56 hr after injection was higher in the cool season than in hot season (P<0.05). Weaning-to-estrus interval (WEI) and injection-to-estrus interval (IEI) were affected by season (P<0.05). Body condition score (BCS) of sows influenced EOI (P<0.01). Sows with low backfat thickness, lactation length <20 days, or litter weight ≥67 kg, had delayed injection-to-ovulation interval (P<0.05). In conclusions, buserelin administration (10 µg, at 72 hr after weaning) advanced ovulation. Hot season prolonged ovulation time. Sows that were weaned with lactation length of at least 20 days, litter weight less than 67 kg, or BCS of at least 3, had better responses to buserelin injection. High backfat reserve after weaning is important for ovulation induction response by buserelin injection.

Expression of PCV2 antigen in the ovarian tissues of gilts.

The present study was performed to determine the expression of porcine circovirus type 2 (PCV2) antigen in the ovarian tissue of naturally infected gilts. Ovarian tissues were obtained from 11 culled gilts. The ovarian tissues sections were divided into two groups according to PCV2 DNA detection using PCR. PCV2 antigen was assessed in the paraffin embedded ovarian tissue sections by immunohistochemistry. A total of 2,131 ovarian follicles (i.e., 1,437 primordial, 133 primary, 353 secondary and 208 antral follicles), 66 atretic follicles and 131 corpora lutea were evaluated. It was found that PCV2 antigen was detected in 280 ovarian follicles (i.e., 239 primordial follicles, 12 primary follicles, 10 secondary follicles and 19 antral follicles), 1 atretic follicles and 3 corpora lutea (P<0.05). PCV2 antigen was detected in primordial follicles more often than in secondary follicles, atretic follicles and corpora lutea (P<0.05). The detection of PCV2 antigen was found mainly in oocytes. PCV2 antigen was found in both PCV2 DNA positive and negative ovarian tissues. It can be concluded that PCV2 antigen is expressed in all types of the ovarian follicles and corpora lutea. Further studies should be carried out to determine the influence of PCV2 on porcine ovarian function and oocyte quality.

Prevalence of constipation and its influence on post-parturient disorders in tropical sows.

The present study aimed to investigate the prevalence of constipation and its influence on farrowing duration and the evidence of post-parturient disorders in tropical sows and to evaluate the efficacy of a laxative supplementation during gestation and around farrowing on the incidence of constipation. Two experiments were performed in a commercial swine herd in Thailand. In experiment 1, the prevalence of constipation was determined in 96 gestating sows. Subsequently, 62 of them (64.6 %), with a severe to moderate degree of constipation, received 20 ml of a laxative for 3 days during gestation. In experiment 2, constipation score was determined in sows before, during, and after farrowing. A total of 98 sows were randomly allocated to one of two groups: the treatment group (n = 48) received 20 ml of a laxative for 3 days before farrowing, and the control group (n = 50) did not receive any laxative. Rectal temperature, appetite score, incidence of postpartum dysgalactia syndrome (PDS), and vaginal discharge score was determined for 4 days. In experiment 1, supplementation of laxative reduced the proportion of sows with moderate to severe constipation (P < 0.05). In experiment 2, sows with moderate to very severe constipation had a 28-min longer duration of farrowing than sows with normal faeces. Constipation in sows on the day of farrowing resulted in reduced appetite on day 1 postpartum (P = 0.008). The incidence of sows with fever on day 1 postpartum was two times higher in sows with constipation than in sows with normal faeces (36.2 and 16.7 %, respectively; P = 0.041).

Postparturient disorders and backfat loss in tropical sows associated with parity, farrowing duration and type of antibiotic.

The present study investigated the incidence of postparturient disorders and backfat loss in primiparous and multiparous sows under tropical climates in relation to duration of farrowing and type of antibiotic used postpartum. In total, 81 sows (42 primiparous and 39 multiparous sows) were included. The sows were categorised according to the duration of farrowing into three groups: <2 (n = 58), 2-4 (n = 19) and >4 h (n = 4). According to the antibiotic used postpartum, the sows were divided into two groups: group I (enrofloxacin type 1, n = 36) and group II (enrofloxacin type 2, n = 45). Rectal temperature, the presence of abnormal vaginal discharge, the occurrence of postpartum dysgalactia syndrome (PDS) and the sows' appetite were determined at days 0, 1, 2 and 3 postpartum. Backfat thickness was measured before farrowing and at 21 days postpartum. The mean duration of farrowing was 114.5 ± 60.2 min. Stillborn piglets in the sows with a long duration of farrowing (>4 h, mean 287.9 min) was higher than in sows with a short duration (<2 h, mean 85.5 min) of farrowing (29.2 and 7.9 %, P = 0.044). Primiparous sows lost more backfat during lactation than multiparous sows (15.7 and 4.8 %, P = 0.004). The incidence of abnormal vaginal discharge (P = 0.046) and PDS (P = 0.057) was less frequent in group II than in group I sows. In conclusion, primiparous sows and sows with a long duration of farrowing had a high risk of postparturient disorders. The type of antibiotic had an effect on the incidence of abnormal vaginal discharge and PDS in sows.

Prevalence of porcine circovirus-2 DNA-positive ovarian and uterine tissues in gilts culled due to reproductive disturbance in Thailand.

The present study aimed to determine the prevalence of porcine circovirus-2 (PCV-2) DNA-positive ovarian and uterine tissues in gilts culled due to reproductive disturbance in Thailand. Tissues (70 ovaries and 102 uteri) and serum (n = 102) samples from 102 gilts were included. PCV-2 DNA was detected by using polymerase chain reactions. The localisation of PCV-2 antigen was determined by immunohistochemistry, and PCV-2 antibody was evaluated by ELISA. PCV-2 DNA was detected in 30.0 % (21/70) of the ovaries and in 45.1 % (46/102) of the uteri. Age did not influence the frequency of PCV-2 DNA detection in these reproductive organs of gilts (P > 0.05). The prevalence of PCV-2 DNA-positive uterine tissue in gilts culled due to non-reproductive problems (20.0 %) was lower than gilts culled due to abortion (85.0 %), abnormal vaginal discharge (47.5 %) and anoestrus (53.5 %) (P < 0.05). The prevalence of PCV-2 DNA-positive uterine tissue in the gilts with high antibody titres (23.0 %) was lower than in gilts with low antibody titres (57.6 %) and seronegative gilts (64.5 %) (P < 0.05). PCV-2 immunostaining was detected in the endometrial cells, lymphocytes and macrophages of the uteri and in oocytes and granulosa cells of the ovaries. In conclusion, the detection of PCV-2 in the reproductive organs reveals an important potential impact of this virus on the reproductive apparatus in gilts.