Association between the incidence of stillbirths and expulsion interval, piglet birth weight, litter size and carbetocin administration in hyper-prolific sows

Timing of dietary zinc additions during gestation for improved piglet survival

The objectives of this study were to determine a practical approach to feeding elevated dietary zinc (Zn) to gestating sows in a commercial setting and to confirm preweaning mortality could be reduced by feeding high Zn to sows during different periods of gestation. The study was conducted at a commercial sow farm in the upper Midwest. Mixed parity sows (n = 267) over three consecutive weekly farrowing groups (sows farrowing within 1 wk) were assigned randomly to one of the three dietary treatments within parity. Treatments consisted of: (1) control sows fed a corn-soybean meal diet containing 206 mg/kg total supplemental Zn supplied by zinc hydroxychloride; (2) breed-to-farrow: as control + 147 mg/kg supplemental Zn as ZnSO4 (353 mg/kg total supplemental Zn) fed from 5 d after breeding to farrowing; and (3) day 110-to-farrow: as control fed from breeding to farrowing + 4,079 mg/kg supplemental Zn as ZnSO4 (4,285 mg/kg total supplemental Zn) starting day 110 of gestation until farrowing. At farrowing, individual piglets were weighed and identified within 12 h of birth. Data were analyzed using PROC GLIMMIX of SAS and the model considered the fixed effect of dietary treatment and random effect of farrowing group. Dietary treatments did not affect number of total pigs born per litter. For breed-to-farrow sows, there was an increase in the percentage of pigs born alive compared to sows fed the control and day 110-to-farrow treatments (P < 0.001). The number of stillborn pigs expressed as a percentage of total litter size at birth decreased for breed-to-farrow sows (P < 0.001) compared with control or day 110-to-farrow sows. Mortality of low birth weight piglets from birth to weaning did not differ among dietary treatments (P = 0.305); however, a trend for decreasing post-natal mortality (P = 0.068) of normal birth weight pigs was observed for pigs born to sows fed elevated Zn 5 d before farrowing. In conclusion, feeding elevated Zn to sows throughout gestation increased the proportion of pigs born alive suggesting that elevated gestational Zn intake makes piglets more robust to endure the stresses of farrowing and decreases intrapartum mortality. Under the conditions of this study, elevated Zn intake of sows did not influence piglet post-natal survival. However, feeding high zinc throughout gestation may decrease piglet mortality during the parturition process.

The influence of parity, body condition, litter size and carbetocin administration on colostrum production and immunoglobulin levels in highly productive sows within a tropical environment

The aim of this study was to explore the factors contributing to colostrum production and the levels of colostrum immunoglobulins (IgG and IgA) in contemporary highly productive sows within a tropical climate. We focused on variables such as parity number, litter size, sow body condition score (BCS), the timing of sample collection following the commencement of farrowing and the use of carbetocin during the birthing process. A total of 100 colostrum samples were collected from a group of 50 Danish Landrace × Yorkshire crossbred sows. These samples were taken at two distinct time intervals: right after farrowing (0 h) and 6 h later. The colostrum samples were classified according to the sows' parity numbers, with 33 samples originating from primiparous sows and 67 from multiparous ones. Additionally, the number of live-born piglets were categorized into three groups: 7-13, 14-17 and ≥ 18 piglets per litter. Moreover, the samples were categorized based on the use of carbetocin during the birthing process, with 34 sows experiencing natural farrowing and 66 sows receiving carbetocin. The sow's BCS was assessed through visual evaluation and palpation. The piglet colostrum consumption and the amount of colostrum produced by the sows were determined. The concentrations of IgG and IgA were determined by using the enzyme-linked immunosorbent assay (ELISA) technique. On average, the colostrum production averaged 5.5 ± 1.7 kg, with IgG and IgA concentrations averaging 54.9 ± 24.6 mg/ml and 7.6 ± 3.5 mg/ml, respectively. Primiparous sows exhibited a significant 25.2% decrease in IgG concentration within 6 h of parturition (P < 0.05), whereas no such decline was observed in multiparous sows. Furthermore, multiparous sows displayed higher colostrum yields (6.2 ± 1.5 kg and 4.3 ± 1.5 kg, respectively, P < 0.001) and IgA concentrations compared to primiparous sows (8.3 ± 3.8 mg/ml and 6.3 ± 2.6 mg/ml, respectively, P = 0.002). Furthermore, a positive correlation was observed between IgA concentrations in colostrum and the sow's BCS at both the 0-h and 6-h post-farrowing time points (r = 0.425, P = 0.002 and r = 0.315, P = 0.031, respectively). The administration of carbetocin did not yield a significant impact on the concentrations of IgG and IgA in the sows' colostrum (P > 0.05). In conclusion, during the initial 6 h after birth, colostrum IgA levels remained stable, whereas there was a noticeable decline in IgG levels, particularly among primiparous sows. The production volume of colostrum and the concentration of IgA in sows within tropical conditions were influenced by both parity number and body condition score.

The impact of the interval between the last meal and the onset of farrowing on the duration of farrowing, stillbirth rates, and colostrum production in highly productive sows in a tropical climate

The present study investigated impact of the interval between the last meal and the onset of farrowing on the duration of farrowing, stillbirth rates, and colostrum production in highly productive sows in a tropical climate. The study involved a total of 92 Danish Landrace x Yorkshire sows (herd A) and 114 French Landrace × Yorkshire sows (herd B). In herd B, a total of 61 sows had their blood samples collected within 1 hr after the onset of farrowing to evaluate their blood glucose levels. The interval between the last meal and the onset of farrowing averaged 5.9 ± 4.5 and 5.4 ± 4.1 hr in herds A and B, respectively. Neither the duration of farrowing nor the occurrence of stillborn piglets in both herds was affected by the time gap between the last meal and the onset of farrowing. At the onset of farrowing, the average blood glucose level in sows was 77.1 ± 19.3 mg/dL, with a range of 27 to 115 mg/dL. There was a positive correlation observed between the blood glucose concentration and the colostrum yield of the sows (r=0.261, P=0.042). In conclusion, the time interval between the last meal and the onset of farrowing did not have any impact on the farrowing performance of sows. However, a higher concentration of blood glucose at the onset of farrowing was associated with an improvement in the colostrum yield of the sows.

Impacts of supplementing Cannabis sativa byproducts during the transition period on behaviour, feed consumption, constipation levels, colostrum production and piglet performance in hyperprolific sows

In the modern swine industry, inflammation and pain in sows after farrowing represent a crucial animal welfare concern. Cannabis sativa, a medicinal plant, has analgesic, anti-inflammatory and antipyretic properties and is rich in fibre. The objective of this study is to examine the impacts of supplementing sows with Cannabis sativa byproducts during transition periods (7 days before and after farrowing) on various aspects including postpartum behaviour, feed intake, constipation, farrowing duration, colostrum yield and piglet performance. The experiment involved a total of 100 Landrace × Yorkshire sows. The sows were distributed according to parity numbers into two groups, i.e., control (n = 54) and treatment (n = 46). The control group was provided with a lactation diet at 3.0-3.5 kg per day for a period of 7 days before and after farrowing. The treatment groups received the same quantity of the diet but with an additional supplementation of 150 g/d of Cannabis sativa byproduct. The byproduct was analysed and contained 0.24 % (w/w) cannabidiol (CBD), resulting in a daily intake of 360 mg of CBD per sow. The conventional lactational diet had a dietary fibre content of 4.3 %, whereas the diet supplemented with Cannabis sativa byproduct had a higher dietary fibre content of 16.9 %. Video cameras were used to observe and document the behaviour of sows within the initial 24 h after farrowing. The duration in which sows engaged in activities such as sleeping, sitting, standing, feeding and nursing their piglets was quantified. Additionally, the rectal temperature of the sows was measured, and a temperature equal to or exceeding 39.5 °C was considered indicative of fever. The faecal score of the sows was assessed, and a faecal score of ≤2 was classified as constipation. On the third day postpartum, the proportion of sows with fever in the treatment group was lower than that in the control group (20.0 % and 38.9 % respectively, P = 0.051). Sows receiving supplementation with Cannabis sativa byproducts exhibited increased durations of standing and feeding compared to those in the control group (P < 0.05). Notably, overall, sows without constipation issues spent more time consuming feed than those experiencing constipation (P = 0.006). The prevalence of constipation was significantly lower in the treatment group compared to the control group (17.4 % and 81.5 %, respectively, P < 0.001). Furthermore, the postpartum sows demonstrated increased feed intake following supplementation with Cannabis sativa byproducts (P < 0.05). Sow colostrum yield, piglet colostrum intake, piglet mortality and other piglet traits did not differ between the control and treatment groups (P > 0.05). In conclusion, supplementing Cannabis sativa byproducts during the transition periods in peri-parturient sows under tropical conditions resulted in a reduction in constipation issues and improved sow activities, such as increased time spent standing and consuming feed within the first 24 h postpartum.

Influence of prepartum feed levels on colostrum production and farrowing performance in highly prolific sows in a tropical environment

Currently, there is a lack of data on the effects of altering feed levels on sow performance and piglet characteristics during the transition period in tropical environments. The present study determined the effect of sow feed levels during the transition period on colostrum yield, colostrum immunoglobulin (Ig) G, colostrum intake of piglets, farrowing duration, proportion of stillborn piglets per litter (SB) and the incidence of farrowing assistance in highly prolific sows. A total of 114 Landrace × Yorkshire crossbred sows and their offspring (n = 2 072) were included in the experiment. Sows were assigned to different feed supply levels from entry to farrowing at 110 days of gestation until farrowing based on their parity number. Three feed-level groups were the control group who received 3.0 kg/day of lactation feed (n = 40), treatment 1 group who received 3.6 kg/day of gestation feed (n = 39) and treatment 2 group who received 4.0 kg/day of lactation feed (n = 35). Colostrum samples (5 ml) were obtained from the sows within 3 h after the onset of farrowing for IgG assay. Piglets were weighed immediately after birth and then again 17-24 h later to estimate their colostrum intake. Colostrum yield was determined by aggregating the colostrum intake of piglets within the litter. The total number of piglets born, SB and farrowing duration were 18.2 ± 3.8, 7.5% and 259.1 ± 138.1 min, respectively. Among these sows, 28.9% experienced a farrowing duration exceeding 300 min and 50.9% required assistance during farrowing. Interestingly, piglets in the treatment 2 group demonstrated a greater colostrum intake (403.1 ± 14.9 g) compared to the control group (360.6 ± 15.1 g, P = 0.046) and the treatment 1 group (361.0 ± 12.9 g, P = 0.033). On average, colostrum yield of sows in the treatment 2 group tended to be higher than in the control group (+0.5 kg, P = 0.081), but did not differ from the treatment 1 group (+0.3 kg, P = 0.191). No significant differences in farrowing duration, SB, farrowing assistance, or colostrum IgG concentration were found across various feed-level groups (P > 0.05). In conclusion, the study showed that raising lactation feed by 1.0 kg/day prefarrowing increased piglet colostrum intake and tended to boost sow colostrum production, without significantly affecting farrowing duration, stillbirth rates, or need for assistance.

Factors affecting birth weight and stillbirth in sows housed in a tropical environment

This study analysed data from a commercial swine herd in Thailand equipped with a free-farrowing housing system, comprising 17,196 piglets from 1318 litters, to explore the impact of sow and litter characteristics on the piglet birth weight and the incidence of stillbirth. The piglets were classified into four groups based on the total number of piglets born per litter (TB): ≤9 (n = 1434), 10-12 (n = 3232), 13-15 (n = 6537) and ≥16 (n = 5993). Sows were classified into four groups based on parity number: 1, 2-4, 5-7 and ≥8. The piglets were categorized into quartiles based on their birth order ranking: Q1 (n = 4786), Q2 (n = 4143), Q3 (n = 3808) and Q4 (n = 4456). Piglet birth weight was individually measured before colostrum ingestion. On average, TB, the number of live-born piglets and the incidence of stillbirth were 13.1 ± 3.7, 11.5 ± 3.8 and 6.3%, respectively. Among these litters, 26.6% had TB numbers ≥16. The average piglet birth weight was 1.37 ± 0.36 kg, with 18.3% of piglets weighing ≤1.0 kg at birth. Piglet birth weight was influenced by birth order ranking, as Q4 piglets were found to be heavier than piglets born in Q1-Q3 (p < .001). Moreover, the percentage of piglets with a birth weight of ≤1.0 kg increased from 5.9% in litters with TB of ≤9-25.3% in litters with TB of ≥16 (p < .001). Additionally, primiparous sows had lower piglet birth weights compared to sows with parity numbers 2-4, 5-7 and ≥8 (p < .001). Piglets born in the fourth quartile (Q4) had a higher risk of stillbirth compared to those born in the first (Q1), second (Q2) and third (Q3) quartiles (12.5% vs. 2.2%, 4.1% and 6.6%, respectively, p < .001). The incidence of stillbirth in litters with TB ≥16 was also higher than that in litters with TB ≤9 and 10-12 (p < .05). Furthermore, sows with parity numbers ≥8 had a higher incidence of stillbirth (9.7%) compared to primiparous sows (4.0%, p < .001), sows with 2-4 parity (5.2%, p < .001) and sows with 5-7 parity (7.6%, p = .003). In summary, a high incidence of stillbirth was found in piglets born in the last quartile of litters, in litters with >16 piglets and for sows with parity numbers ≥8. Piglets born in the last quartile of litters were heavier than those born in the first to third quartiles.

Factors associated with farrowing assistance in hyperprolific sows

OBJECTIVE

The present study was performed to determine risk factors associated with the frequency of farrowing assistance in hyperprolific sows in a tropical environment and to investigate the impacts of farrowing assistance on piglet colostrum consumption and sow colostrum yield.

METHODS

Farrowing data from 352 Landrace×Yorkshire crossbred sows and 5,554 piglets in five commercial swine herds in Thailand were investigated. The sows were classified according to parity numbers: 1 (n = 72), 2 to 4 (n = 128), 5 to 6 (n = 84), and ≥7 (n = 68) and the total number of piglets born per litter (TB): 10 to 13 (n = 90), 14 to 16 (n = 117), and ≥17 (n = 145). The incidence of farrowing assistance and associated parameters were investigated.

RESULTS

The TB and farrowing duration averaged 15.8±0.2 and 279.9±11.2 min, respectively. The percentage of sows that required farrowing assistance was 29.8% and varied among herds from 5.7% to 53.3% (p<0.001). The percentage of piglets born after birth assistance using manual intervention was 8.4%. Sows with parity numbers 1 and 2 to 4 had a lower frequency of farrowing assistance than sows with parity numbers ≥7 (p<0.01). The colostrum yield of sows that required farrowing assistance did not differ from sows that farrowed without assistance (5.3±0.2 and 5.1±0.1 kg; p = 0.288); however, the colostrum consumption of piglets born from sows that required farrowing assistance was lower than those born from sows that farrowed without assistance (302.2±15.7 and 354.2±5.6 g; p<0.001). Blood oxygen saturation of the piglets born after birth assistance tended to be lower than the piglets that farrowed without birth assistance (87.8%±1.3% vs 90.4%±0.4%; p = 0.054).

CONCLUSION

The frequency of farrowing assistance in sows varied among herds and was influenced by parity number. The piglets born after receiving birth assistance should receive special care to improve their blood oxygen saturation and enhance colostrum intake.

Relationship between piglets' survivability and farrowing kinetics in hyper-prolific sows

BACKGROUND

Prolonged farrowing and more piglets born with low birth weight are undesirable consequences of genetic selection for increased litter size. The objective of the present observational study was to evaluate the relationship between piglets' survivability and farrowing kinetics in hyperprolific sows. A total of 58 sows of different parities and 1190 piglets were included. The entire farrowing process was monitored and the following parameters were recorded: inter-piglet birth interval, birth order, total born, live born, dead born, and mummified piglets, obstetric intervention, weight at birth and 24h, colostrum yield and intake.

RESULTS

The sows included in this study had on average 20.6 ± 0.6 total piglets born, of which 16.4 ± 0.6 were live born, 3.3 ± 0.4 were stillborn and 0.9 ± 0.2 were mummified piglets. The average farrowing duration and average birth interval were 411.3 ± 31.6 and 20.6 ± 1.7 min, respectively. Farrowing duration was positively associated (p < 0.05) with parity, number of stillborn and mummified piglets. Piglet mortality 24h after birth was negatively affected (p < 0.01) by birth weight and positively affected (p < 0.01) by cumulative birth interval. The last tercile of piglets born (birth order ≥ 17) had the highest (p < 0.01) inter-piglet birth interval (IPBI) (43.4 ± 4.17 min) compared to piglets born in the first (birth order between 2 and 7) (26.5 ± 3.8 min) and second (birth order between 8 and 16) terciles (21.9 ± 3.8 min). Cumulative birth interval, birth weight, occurrence of stillborn piglets and manual intervention were positively associated (p < 0.05) with IPBI. Piglet birth weight was also positively associated (p < 0.01) to individual colostrum intake. Piglets ingesting more colostrum had lower (p < 0.01) mortality from 24h after birth until weaning. Sow's parity and cumulative birth interval were positively associated with the presence of stillborn piglets (p = 0.02 and p < 0.01, respectively).

CONCLUSION

Reducing farrowing duration may be crucial to decrease stillbirth rate and neonatal mortality in hyperprolific sows. Moreover, special care must be provided to the lighter piglets within a litter to increase their colostrum intake and minimize piglet's mortality throughout lactation.

Managing prolific sows in tropical environments

Litter size in modern sows has been dramatically improved in recent decades by genetic selection for highly prolific sows. In a tropical environment, the average total number of pigs born and number born alive are reported to be as high as 17.2 and 15.1 piglets per litter, respectively. Therefore, the new production target in many herds aims to achieve 30-40 pigs weaned per sow per year. Despite the improvements in litter size, the mean preweaning piglet mortality rate remains high, at between 10% and 20%, in major pig-producing countries. A sufficient daily feed intake by lactating sows is important for high milk production as sow milk yield is the limiting factor for piglet growth rate. Heat stress, which can occur when the ambient temperatures rise above 25°C, is one of the major problems that decreases daily feed intake and compromises milk yield. Therefore, it is necessary to encourage high feed intakes to achieve high milk yields. However, even with high nutrient intakes, productivity can be constrained by intestinal barrier function, limiting digestive ability, and allowing potential pathogens and/or toxins to become systemic. This is more likely greater under tropical conditions because of heat stress, exacerbating sow fertility problems. Underpinning sow herd performance, including responses to environmental challenges, is the selection of appropriate gilts, for example, selection and management for early puberty, thus presumably selecting the more fertile gilts and the correct management of lactation to improve the number of weaned piglets are some of the key factors for future reproductive efficiency of the farm under tropical conditions.

Sow Nutrition, Uterine Contractions, and Placental Blood Flow during the Peri-Partum Period and Short-Term Effects on Offspring: A Review

The birth process is a crucial event for piglet survival. Along with increasing litter sizes, not only has the duration of parturition increased, but placental blood flow per piglet has reduced and placental area per piglet has become smaller, making these piglets more susceptible for hypoxia. Diminishing the risk of piglet hypoxia by either reducing the total duration of parturition or increasing fetal oxygenation may reduce the incidence of stillbirth and early post-partum mortality. This review discusses options to do so by nutritionally supporting the sow in the final pre-partum period, after discussing the role of uterine contractions and placental blood flow. Providing sufficient energy seems to be a logical first step, but also other nutrients needed for uterine contractions, such as calcium, or enhancing uterine blood flow by using nitrate seem promising. These nutrient requirements may depend on litter size.

Factors Associated with Farrowing Duration in Hyperprolific Sows in a Free Farrowing System under Tropical Conditions

The ongoing selection for increased litter size has had significant impacts on sow husbandry practice. The present study investigated factors associated with farrowing duration and the proportion of sows that had prolonged farrowing in modern hyperprolific sows kept in a free farrowing system in a tropical environment. Farrowing data from 2493 Landrace x Yorkshire cross-bred sows in a commercial swine herd in Thailand were included in the study. The time of farrowing, parity number, litter size, and the birth status of each piglet were recorded. Farrowing duration was analysed using multiple analyses of variance. Total number of piglets born per litter (TB), parity, and time onset of farrowing were included in the statistical models. On average, TB, piglets born alive, and farrowing duration were 13.7, 12.1, and 221.0 min, respectively. Of these sows, 26.4% had TB ≥ 16 and 21.7% had a prolonged farrowing duration (≥300 min). Farrowing duration was positively correlated with TB (r = 0.141, p < 0.001), percentage of stillborn (SB) piglets per litter (r = 0.259, p < 0.001), percentage of mummified foetuses (MF) per litter (r = 0.049, p = 0.015), piglet birth weight (r = 0.068, p < 0.001), and litter birth weight (r = 0.041, p = 0.043). The proportion of SB per litter was higher and piglet birth weight lower in litters that had ≥16 TB than those with 8−12 TB (p < 0.05). The farrowing duration of sows with parity numbers 5−7 (247.7 ± 5.1 min) and 8−10 (237.1 ± 5.1 min) was longer than that of sows with parity numbers 1 (188.3 ± 5.2 min) and 2−4 (214.3 ± 3.9 min) (p < 0.05). Sows that had started farrowing during working hours had longer farrowing durations (229.3 ± 3.6 min) than those that had started farrowing during non-working hours (217.6 ± 3.4 min, p = 0.017). In multiparous sows, the duration of farrowing was positively correlated with the maximum temperature (r = 0.056, p = 0.012) and the maximum temperature−humidity index (r = 0.059, p = 0.008) in the 7 days before farrowing. The present data confirm that TB, sow parity, and time of onset of farrowing are significant risk factors for a prolonged farrowing.

Effect of a combination of altrenogest and double PGF2α administrations on farrowing variation, piglet performance and colostrum IgG

The variation of gestation length in sows leads to difficulties performing farrowing supervision. The present study was performed to investigate whether oral administration of altrenogest until 112 days of gestation and double administration of PGF2α at 113 days of gestation can synchronise the onset of parturition in sows and minimise deleterious effects on the incidence of stillbirths and colostrum quality. Additionally, the effects of synchronised farrowing on colostrum yield and piglet birth weight, colostrum intake and survival rate of piglets until seven days of postnatal life were also investigated. In total, 193 Landrace x Yorkshire crossbred sows were randomly allocated according to parity number into two groups, i.e. control (n = 95) and treatment (n = 98). The control sows were allowed to farrow naturally. The treatment sows were orally administered 20 mg per day of altrenogest for four days from 109 to 112 days of gestation and were administered PGF2α twice on day 113 of gestation. Individual body weight at birth and 24 h after birth of piglets in all litters were determined in both control (n = 1609) and treatment (n = 1707) groups. Colostrum consumption of all piglets, colostrum yield, colostrum IgG and serum progesterone of sows were determined. On average, the total number of piglets born per litter were 17.0 ± 3.1. The proportion of sows farrowed before 114 days of gestation was higher in the control than the treatment group (8.4% and 2.0%, respectively, P = 0.05) and 92.8% of sows in the treatment group farrowed on day 114 of gestation. The percentage of stillborn piglets per litter did not differ significantly between control and treatment groups (4.5% and 4.6%, respectively). Colostrum yield of sows did not differ between control and treatment groups (5.52 ± 0.13 and 5.28 ± 0.12 kg, respectively, P = 0.174). However, colostrum intake of piglets was lower in the treatment than the control group (354.7 ± 6.6 and 381.2 ± 7.0 g, respectively, P = 0.012). Colostrum IgG was higher in the control than the treatment group (41.2 ± 1.1 and 37.3 mg per ml, P = 0.013). In conclusion, altrenogest treatment from 109 to 112 days and double administrations of PGF2α on day 113 of gestation can control gestation length in sows. No deleterious effects of this protocol on the incidence of stillbirths and sow colostrum yield were detected. However, piglet colostrum intake and colostrum IgG were compromised. Thus, care of newborn piglets in the treatment group should be considered.

Combined Effect of Sow Parity and Terminal Boar on Losses of Piglets and Pre-Weaning Growth Intensity of Piglets

This study analysed the effect of sow parity (P), terminal boars (TB), and their combination on reproductive parameters of sows, losses of piglets, and their individual live-weight (LW) and average daily gain (ADG) from birth to weaning. A total of 120 sows of Large White × Landrace hybrid combination from the first to the fourth parity (30 sows per parity) were included in the observation. The sows were inseminated by terminal boars of Pietrain (Pn), Large White_sireline (LW_SL), and Duroc (D) breeds and Duroc × Large White_sirelinie (D × LW_SL), Large White_sirelinie × Pietrain (LW_SL × Pn), and Duroc × Pietrain (D × Pn) hybrid combinations (20 sows per terminal boar population). The results proved a significant effect of P on the total numbers of piglets (TN), the numbers of stillborn piglets (SB), and the pre-weaning losses of piglets (L) (p ≤ 0.01) with the lowest losses found in the third parity sows. A significant effect of TB was confirmed for TN, the numbers of live-born piglets (LB), SB, the numbers of mummified piglets (M) and non-viable piglets (N), and (L) (p ≤ 0.01). The sows inseminated by D and LW_SL boars showed the lowest total numbers of piglets but also the highest survivability of piglets until weaning. Significant effects of interaction between P and TB were observed for the TN, SB, N, and L (p ≤ 0.05). Evaluation of growth parameters in piglets (n = 1547) showed that P significantly influenced LW in the first three weeks of life (p ≤ 0.01) and ADG from birth to Day 7 and from Day 15 to Day 21 (p ≤ 0.01). Additionally, a significant effect (p ≤ 0.01) of TB was proven on individual weight and ADG in all the observed time intervals, with the highest growth found in the piglets of the D and LW_SL boars. Significant interactions (p ≤ 0.01) between P and TB were found for LW and ADG in all the time intervals.

Strategies of inorganic and organic trace mineral supplementation in gestating hyperprolific sow diets: effects on the offspring performance and fetal programming

The aim of the present study was to evaluate the effect of trace mineral nutrition on sow performance, mineral content, and intestinal gene expression of neonate piglets when inorganic mineral sources (ITM) were partially replaced by their organic mineral (OTM) counterparts. At 35 d postmating, under commercial conditions, a total of 240 hyperprolific multiparous sows were allocated into three experimental diets: 1) ITM: with Zn, Cu, and Mn at 80, 15, and 60 mg/kg, respectively; 2) partial replacement trace mineral source (Replace): with a 30 % replacement of ITM by OTM, resulting in ITM + OTM supplementation of Zn (56 + 24 mg/kg), Cu (10.5 + 4.5 mg/kg), and Mn (42 + 18 mg/kg); and 3) Reduce and replace mineral source (R&R): reducing a 50% of the ITM source of Zn (40 + 24 mg/kg), Cu (7.5 + 4.5 mg/kg), and Mn (30 + 18 mg/kg). At farrowing, 40 piglets were selected, based on birth weight (light: <800 g, and average: >1,200 g), for sampling. Since the present study aimed to reflect results under commercial conditions, it was difficult to get an equal parity number between the experimental diets. Overall, no differences between experimental diets on sow reproductive performance were observed. Light piglets had a lower mineral content (P < 0.05) and a downregulation of several genes (P < 0.10) involved in physiological functions compared with their average littermates. Neonate piglets born from Replace sows had an upregulation of genes involved in functions like immunity and gut barrier, compared with those born from ITM sows (P < 0.10), particularly in light piglets. In conclusion, the partial replacement of ITM by their OTM counterparts represents an alternative to the totally inorganic supplementation with improvements on neonate piglet gene expression, particularly in the smallest piglets of the litter. The lower trace mineral storage together with the greater downregulation of gut health genes exposed the immaturity and vulnerability of small piglets.

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.

Effects of uterotonics on farrowing traits and piglet vitality: A systematic review and meta-analysis

Uterotonics are widely used in the pig industry but their effects have not been investigated critically. The objective was to evaluate the effects of oxytocin and carbetocin on farrowing duration, birth interval, farrowing assistance, stillbirth rate, and piglet viability traits by performing a systematic review and a meta-analysis. The search for studies was performed during January 2020 using the PubMed, ISI Web of Science, Science Direct, and Scopus databases. The literature search was conducted using the key words: oxytocin, pig, farrowing, stillbirth, piglet, dose, and carbetocin. Studies which evaluated the effects of oxytocin or carbetocin on farrowing duration, birth interval, stillbirth rate, and farrowing assistance were included in the review. Of 1215 articles, 23 (1.9%) were selected for fulfilling the criteria for inclusion in the present study. A high variety of doses was observed among studies. Oxytocin increased (30%; P < 0.05) the stillborn proportion in the litters compared to control sows. Both oxytocin and carbetocin increased the need of farrowing assistance by 137% (P < 0.01) and 40% (P < 0.05), respectively, compared to control. The use of oxytocin reduced the farrowing duration by 18% and the birth interval by 17%, while carbetocin reduced the same responses by 27 and 23%, respectively (P < 0.01). When used judiciously, uterotonics are a valuable tool to shorten farrowing duration of hyperprolific sows. However, the treatment is not exempt of deleterious effects for piglets and sows. Therefore, the criteria to use these drugs should be based on individual cases and not as part of hormonal protocols for all parturient 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.

Risk factors associated with stillbirth of piglets born from oxytocin-assisted parturitions

Aim:

The present study aimed to investigate the effects of different risk factors on stillbirth of piglets born from oxytocin-assisted parturitions.

Materials and Methods:

Data were collected from a total of 1121 piglets born from 74 Landrace x Yorkshire crossbred sows from a herd. Logistic regression models were used to determine the associations between stillbirth and different risk factors including parity (1, 2, 3-5, and 6-10), gestation length (GL) (112-113, 114-116, and 117-119 days), litter size, birth order (BO), sex, birth interval (BI), cumulative farrowing duration, birth weight (BW), crown rump length, BW deviation, body mass index, ponderal index (PI), and the use of oxytocin during expulsive stage of farrowing.

Results:

The incidence of stillbirth at litter level and stillbirth rate was 59.5% (44/74) and 8.1% (89/1094), respectively. The final multivariate logistic regression selected BO, BI, PI, GL, and parity as the five most significant risk factors for stillbirth. Increased BO and BI, GL <114 and >116 days, parity 6-10, and low PI increased the stillbirth rate in piglets.

Conclusion:

Several factors previously determined as risks for stillbirth in exogenous oxytocin-free parturitions also existed in exogenous oxytocin-assisted parturitions. One dose of oxytocin at fairly high BO did not increase stillbirth, whereas two doses of oxytocin were potentially associated with increased values.

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.

Sow and piglet traits associated with piglet survival at birth and to weaning

AbstractUnderstanding the relationship between sow and piglet characteristics that are associated with stillborn rate and preweaning mortality is beneficial as litter size continues to increase. Two experiments were previously conducted to evaluate prefarrowing nutrition regimens on sow and litter characteristics. These two datasets (experiments 1 and 2) were then used to identify sow and piglet characteristics associated with stillborn rate and piglet survival to weaning. A total of 1,201 sows that gave birth to 19,168 pigs comprised the dataset. The following characteristics were used in multivariate logistic regression analysis for traits associated with stillborn rate or survival to weaning: parity, litter weight, mean piglet birth weight, sow backfat, and BW at day 113 of gestation, gestation length, farrowing duration, litter size, piglet birth order, farrowing assistance, pig to teat ratio, colostrum intake, and colostrum yield. Sows within each experiment (herd) were categorized into quartiles for each of the independent variables to quantify the relationship to stillborn rate or survival to weaning. Increased stillborn rate was associated (P < 0.01) with heavier litter weights, lighter piglet birth weights, and larger litters in both experiments. In experiment 1, increased stillborn rate was associated (P < 0.01) with longer farrowing duration. Increased stillborn rate was associated with sows with less backfat depth at day 113, older parity, or increased farrowing assistance in experiment 2. In both experiments, pigs born later in the birth order had an increased (P < 0.01) risk of being stillborn. In both experiments, heavier piglet birth weight, greater colostrum intake, and lower total born were associated (P < 0.01) with increased survival to weaning. In experiment 2, pigs born in the first 75% of the litter, or in a litter with lower pig to teat ratio were associated (P < 0.01) with increased survival to weaning. Although the stillborn rate was similar between experiments (6.5% vs. 6.6%), differences in the traits associated with stillborn rate between studies indicate that some associated traits may be herd dependent. However, improving piglet birth weight, placing an emphasis on assisting pigs born later in the birth order and increasing colostrum intake will increase piglet survival from birth to weaning.

Are Larger Litters a Concern for Piglet Survival or an Effectively Manageable Trait?

As sows continue to be selected for greater prolificacy, it is important to review problems that arise in larger litters, and whether these issues can be appropriately managed. Although a proportion of piglets in larger litters can be born underweight, proper supervision around farrowing and adequate colostrum intake has the potential to improve the survival of low-birth-weight piglets and their ongoing growth to weaning. As larger litters can impart greater stress and discomfort on sows, implementing a low-stress environment leading up to parturition may improve sow performance and subsequent survival of piglets. Additionally, treating sows with anti-inflammatory compounds, either dietary or pharmacologically, shows some promise for alleviating sow discomfort and improving piglet survival in larger litters. Understanding that selecting sows for larger litters not only affects piglet survival but the well-being of the sow, the decision to continue selecting for larger litters, regardless of management strategies, remains a topic of ethical concern.