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A database containing 12,110 farrowing records from 16 commercial farms was abstracted from the PigCHAMP[R] production information system. The farms were selected based on the willingness of producers to keep records and average weaning age. The ADFI records of 10,846 of these lactating sows were also obtained. Sows weaned at [less than or equal to] 7 and > 28 d after farrowing were excluded. Farrowing rate excluding sows culled for nonreproductive reasons after mating from the denominator was 85.5%. Parity, farrowing season, and the lactation length x ADFI interaction were associated with farrowing rate (P < .05) using a categorical additive linear model in the CATMOD procedure in SAS (1988). Parity 1 sows had a lower farrowing rate than parities 2 and [greater than or equal to] 6 (P < .05). The summer and spring groups had the lowest and second-lowest farrowing rates among the four seasons (P < .05). In the high ADFI ([greater than or equal to] 5.7 kg) group, no differences in farrowing rate were observed between lactation length groups. In the low ([less than or equal to] 4.2 kg) and medium (4.2 to 5.6 kg) ADFI groups, farrowing rate varied depending on lactation length. In conclusion, our results suggest that optimizing ADFI ([greater than or equal to] 5.7 kg) alleviates the negative effects of lactation length on farrowing rate. Key Words: Farrowing Rate, Lactation Duration, Feed Intake, Reproductive Efficiency

This experiment was conducted to determine the effects of gestational energy intake on glucose tolerance, LH profiles, and reproductive performance of first-litter sows. Sixteen pregnant gilts were assigned to either high energy (11 Mcal of ME/d; H) or normal energy (6.5 Mcal of ME/d; N) diets during gestation. They did not receive the treatment diets until 35 d of gestation and had free access to the same commonly used diet during lactation. A glucose tolerance test (1 g glucose per kg BW) was conducted after 18 h of feed deprivation on 110 d of gestation and 15 d of lactation. Blood samples were collected at -10, -5, 0 (immediately before glucose infusion), 2, 4, 6, 8, 10, 15, 20, 25, 30, 40, 50, 60, 80, 100, 120, 150, and 180 min for assay of glucose and insulin concentrations. Blood samples were also taken on d 7, 14, and 21 of lactation and on 1 d postweaning for 6 h with 10-min intervals for LH characteristics. Sows in Group H had greater gain of BW and backfat during gestation (P < .001) and had less feed intake and greater weight loss during lactation (P < .002) than those in Group N. Sows in Group H (8.0 d) showed 1.6 d longer (P = .07) weaning-to-estrus intervals than those in Group N (6.4 d). After glucose infusion, insulin levels in Group H were higher (P < .05) than those in Group N. Lower LH concentrations on 1 d postweaning were found (P < .05) in sows in Group H than in Group N. This study indicates that energy intake during gestation is negatively related to feed intake during lactation. Reduced feed intake during lactation of sows having high gestational energy impairs glucose tolerance, suggesting that interaction of insulin with LH secretion may influence weaning-to-estrus intervals. Key Words: Energy Intake, Glucose Tolerance, Insulin, Luteinizing Hormone, Sows

Daily feed intake during lactation was recorded for 20,296 lactating sows on 30 commercial farms in the United States. Each lactation feed record was categorized into one of six patterns: RAPID, rapid increase in feed intake; MAJOR, major drop; MINOR, minor drop; LLL, low feed intake throughout lactation; LHH, low intake during the 1st wk then an increase in feed intake for the remainder of lactation; and GRADUAL, gradual increase. A database containing 24,340 farrowing records and 19,015 subsequent litter records were abstracted from the PigCHAMP[R] data files of the farms enrolled in the study. Multiple regression analyses revealed that ADFI during lactation had nonlinear or linear associations with weaning-to-first service interval (WSI), weaning-to-conception interval (WCI), litter weight at weaning (WWT), and subsequent litter size (SLS). Sows having LLL and LHH had longer (P < .01) WSI and WCI than the other patterns. Sows with MAJOR had a longer WCI (P < .05) than females with RAPID. Further, sows having MAJOR had lighter (P < .01) WWT than those with RAPID, MINOR, and GRADUAL. Sows having MAJOR had a higher (P < .01) proportion of females culled for anestrus relative to RAPID. Furthermore, sows exhibiting a drop in feed intake in either wk 1 or 2 were more likely to be culled for anestrus than sows having no drop. These results suggest that both the amount and pattern of feed intake during lactation influence subsequent reproductive performance. Key Words: Lactation, Sows, Feed Intake, Reproductive Disorders, Weaning Weight, Reproductive Efficiency

This study created and used a database containing 25,719 farrowing and 19,393 subsequent litter records abstracted from the PigCHAMP[R] records of 30 commercial farms and daily feed intake records of 25,040 of these lactating sows. Each lactation feed record was categorized into one of six patterns: RAPID, rapid increase in feed intake following farrowing; MAJOR, major drop in feed intake during lactation; MINOR, minor drop; LLL, low feed intake throughout lactation; LHH, low feed intake during the first week then increasing for the remainder of lactation; and GRADUAL, gradual increase in feed intake throughout lactation. At the herd level, patterns RAPID, MAJOR, MINOR, LLL, LHH, and GRADUAL were observed in 22.8%, 32.9%, 27.8%, 1.0%, .8%, and 14.7% of sows, respectively. On a sow basis, across all feed intake records of all farms, patterns RAPID, MAJOR, MINOR, LLL, LHH, and GRADUAL were observed at frequencies of 17.8%, 38.3%, 25.8%, 1.2%, 1.5%, and 15.4%, respectively. Using logistic regression, the risk factors affecting the occurrence of MAJOR and MINOR patterns were lower parity, thicker backfat, higher room temperature, and greater feed intake during early lactation. Average daily feed intake and the day of peak intake were 5.2 (1.4 SD) kg/sow and 12.6 (4.6 SD) d after farrowing. Regression coefficients of factors affecting ADFI derived from multiple regression analyses were 247 g for parity, 9 g for weaning litter weight (kg), -13 g for room temperature ([degrees] C), 62 g for lactation length (d), and -.4 g for energy density (kcal/kg). This study demonstrated substantial individual sow and farm variation in overall feed intake and pattern of feed intake during lactation. It also identified key risk factors (i.e., parity, lactation length, room temperature, weaning litter weights, energy density) for ADFI and pattern of feed intake on commercial farms. Key Words: Sows, Lactation, Feed Intake, Feeding Behavior

Thirty-six primiparous sows were assigned to one of five treatments designed to mimic the lactation feed intake patterns observed in a previous study of commercial farms: high energy intake (HHH) or low energy intake during each week of a 3-wk lactation (LLL), or reduced intake during wk 1 (LHH), wk 2 (HLH) or wk 3 of lactation (HHL). The metabolizable energy intake of sows was either 16.5 (H) or 6.5 (L) Mcal/d. Diets were equal in lysine, providing 45 g/d. The HHH sows had a shorter (P < .05) weaning-to-estrus interval (9 [+ or -]3.2 d) than the sows in the LLL (23 [+ or -]3.5 d), HLH (22 [+ or -]3.5 d), and HHL (18 [+ or -]3.2 d) groups. The LH pulse frequencies of HHH (d 14:1.5 pulses/8 h; d 21:2.1 pulses/8 h) were greater (P < .05) than those of LLL (.2 pulses/8 h) and HLH (.5 pulses/8 h) on d 14 and those of LLL (0 pulses/8 h) and HHL (.9 pulses/8 h) on d 21 of lactation. No differences (P >.1) in mean serum concentrations of LH were observed among treatment groups either on d 21 of lactation or on d 1 postweaning. When fed a low-energy diet, sows had lower (P < .05) concentrations of serum insulin and plasma glucose than did sows fed a high-energy diet. Our results indicate that energy intake during lactation influences circulating insulin and glucose levels and LH pulse frequency and amplitude during mid-lactation and during the postweaning period. Key Words: Lactation, Sows, Luteinizing Hormone, Insulin, Glucose, Energy

High temperature is an environmental factor that impairs sow fertility. In this study, we identified the critical weeks for heat stress effects on aspects of fertility performance, namely weaning-to-first-service interval (WSI) and farrowing rate (FR). We also examined the threshold temperatures above which the fertility performance deteriorated and whether there were any differences between parities regarding heat stress effects or thresholds. Performance data of sows in 142 herds from 2011 to 2016 were matched to appropriate weekly averaged daily maximum temperatures (T max ) from weather stations close to the herds. Two types of ratios (i.e. ratio for WSI and odds ratio for FR) were used to identify the critical weeks for heat stress by comparing the respective measures for two sow groups based on T max in different weeks around weaning or service events. The ratios for WSI were calculated between groups of sows exposed to T max ≥ 27 °C or <27 °C in each week before weaning, with the T max cutoff value based on a recent review study. Similarly, the odds ratios for FR for the two groups were calculated in weeks around service. The weeks with the largest differences in the fertility measures between the two T max groups (i.e. the highest ratio for WSI and the lowest odds ratio for FR) were considered to be the critical weeks for heat stress. Also, piecewise models with different breakpoints were constructed to identify the threshold T max in the critical week. The breakpoint in the best-fit model was considered to be the threshold T max. The highest ratios for WSI were obtained at 1 to 3 wk before weaning in parity 1 and 2 or higher sow groups. The threshold T max leading to prolonged WSI was 17 °C for parity 1 sows and 25 °C for parity 2 or higher sows. Increasing T max by 10 °C above these thresholds increased WSI by 0.65, and 0.33 to 0.35 d, respectively (P < 0.01). For FR, the lowest odds ratios were obtained at 2 to 3 wk before service in parity 0, 1, and 2 or higher sow groups. The threshold T max leading to reductions in FR was 20, 21, and 24 to 25 °C for parity 0, 1, and 2 or higher sow groups, respectively. Increasing T max by 10 °C above these thresholds decreased FR by 3.0%, 4.3%, and 1.9% to 2.8%, respectively (P < 0.01). These results indicate that the critical weeks for heat stress were 2 to 3 wk before service for FR and 1 to 3 wk before weaning for WSI. The decreases in fertility performance in parity 0 to 1 sows started at temperatures 3 to 8 °C lower than in parity 2 or higher sows. [ABSTRACT FROM AUTHOR]

Objective To characterize obese or overweight dogs that visited private Japanese veterinary clinics located in humid subtropical climate zones. Methods Dogs were categorized into four body condition score groups and five body size groups based on their breed. Multilevel logistic regression models were applied to the data. A Chi -squared test was used to examine whether the percentage of obese or overweight dogs differed between breeds. Results There were 15.1% obese dogs and 39.8% overweight dogs. Obese dogs were characterized by increased age and female sex, whereas overweight dogs were characterized by increased age and neuter status ( P < 0.05). Peak probabilities of dogs being either obese or overweight were between 7 and 9 years of age, with the probabilities then declining as the dogs got older. For example, in toy sized dogs, the probability of dogs being overweight increased from 33.4% to a peak of 55.1% as dog age rose from 1 to 8 years old. Also, in medium, small and toy sized dogs, neutered dogs were more likely to be overweight than intact dogs, whereas neutered small sized dogs were more likely to be obese than intact small sized dogs ( P < 0.05). Additionally, the percentages of obese or overweight dogs differed between the 10 selected breeds with the highest percentage of obese or overweight dogs. Conclusions By taking age, body size, sex and neuter status into account, veterinarians can advise owners about maintaining their dogs in ideal body condition. [ABSTRACT FROM AUTHOR]

The objective of the present study was to compare lifetime reproductive performance and survival probability of English Berkshire female pigs and crossbred females in a subtropical region of Japan. We analyzed records of 20,417 females entered into the 12 herds in Southern Japan from 2003 to 2007. Generalized linear mixed-effects models were conducted to compare the lifetime reproductive performance of the Berkshire and crossbred females. Multilevel mixed-effects models were conducted to compare the lifetime reproductive performance of the Berkshire and crossbred females. Also, a multilevel proportional hazard model was used to examine the survival probabilities for the two breeds. Berkshire gilts were 39.8 days older at first-mating than crossbred gilts ( P = 0.05). The pigs born alive (PBA) in Berkshire and crossbred gilts increased from 5.8 to 6.9 pigs and from 10.7 to 11.1 pigs, respectively, as age at first-mating increased from 220 to 310 days old ( P < 0.05). More Berkshire gilts were culled for reproductive failure than crossbred gilts (7.5 vs. 3.8 %; P < 0.05). Also, Berkshire females had 2.7 lower parity at removal, 224.4 days lower reproductive herd-life, and 4.2 pigs fewer average lifetime PBA than crossbred females ( P < 0.05) and tended to have a lower survival probability ( P = 0.05). In summary, Berkshire females had later puberty, were more sensitive to age at first-mating for increasing PBA, and had lower fertility and a lower survival probability than crossbred females in commercial herds. [ABSTRACT FROM AUTHOR]

The objectives of this study were to determine the associations between climatic factors and production factors for returns to service of female pigs during summer and to quantify the associations between these factors and occurrences of returns to service. The factors that were assessed were as follows: maximum temperature (HT), relative humidity, age of gilts at first mating, parity, weaning-to-first-mating interval (WMI), and lactation length. The study analyzed records of 18,307 gilts in 99 herds and 78,135 parity records of 56,322 sows in 103 herds; all the females were first-serviced between June and September, 2007 to 2009. Average daily HT and relative humidity for 15 days post-service of a female were obtained from 21 local weather stations and coordinated with the performance data of the respective local herds. The returns to service were categorized into three groups: regular returns (RRs: 18–24 days), irregular returns (IRs: 25–38 days), and late returns to service (LRs: 39 days or later). Two-level mixed-effects models were applied to the data by using a herd at level 2 and an individual record at level 1. In mated gilts, the occurrences (%) of RRs, IRs, and LRs were 4.8%, 1.8%, and 5.3%, respectively. In mated sows, the respective occurrences were 3.3%, 1.8%, and 4.2%. Mean values (ranges) of HT and relative humidity were 28.4 °C (13.6 °C–39.8 °C) and 73.4% (35.0%–98.0%), respectively. In gilts, as HT increased from 25 °C to 30 °C, the occurrence of RR increased from 3.7% to 4.4% (P < 0.05). However, there was no association between the occurrence of RR and either relative humidity (P = 0.17) or age at first mating (P = 0.23). In addition, there were no associations between the occurrences of either gilt IR or LR and HT (P ≥ 0.05), relative humidity (P ≥ 0.46), or age at first mating (P ≥ 0.32). In sows, greater occurrences of RRs, IRs, and LRs were associated with higher HT, lower parity, and a WMI of 7 days or longer (P < 0.05), but they were not associated with relative humidity (P ≥ 0.62) or lactation length (P ≥ 0.13). The occurrence of RRs in sows of all WMI groups increased 1.22 (1.045) times for each 5 °C increase in HT. For sows with WMI 0 to 6 days, each 5 °C rise in HT increased the occurrence of IRs and LRs by 1.36 (1.065) and 1.27 (1.055) times, respectively. However, there was no association between increased HT and occurrences of IRs or LRs for sows with WMI 7 days or longer (P ≥ 0.38). Therefore, in order to prevent returns to service, it is recommended that producers apply cooling management for females during the post-service periods in summer. [ABSTRACT FROM AUTHOR]

The objective of the present study was to investigate culling guidelines for gilts and sows in Japanese commercial herds and to compare differences between culling guidelines and actual culling practices in different herd productivity groups. A questionnaire survey was undertaken to obtain information on culling guidelines in 115 commercial swine herds that participated in the PigCHAMP data-share program. The questionnaire included questions on guideline values for culling intervals and the number of conception failure occurrences that would trigger a culling decision to be made. Ninety-two of the 115 herds (80.0%) returned appropriate data for the study and were included in the present study. In addition to questionnaire data, culling data regarding the actual culling intervals and number of reservices for gilts and sows culled during 2007 to 2008 were also obtained for the same herds from a PigCHAMP database. Culled gilts and sows were divided into 4 female groups on the basis of the stages of their reproductive life when they were culled: unmated gilts, mated gilts, unmated sows, and mated sows. Culling intervals in unmated gilts and sows were denned as the number of days from birth or weaning to culling, respectively, whereas in mated gilts and sows culling intervals were the number of days from last service to culling. Three herd productivity groups were formed on the basis of the upper and lower 25th percentiles of pigs weaned mated female"1 yr"1: high-, intermediate- or low-performing herds. For unmated gilts and sows actual culling intervals were 15 d shorter than the guideline culling intervals in the surveyed data submitted by producers (P < 0.05). This shorter actual culling period for unmated gilts and sows did not vary significantly between herd productivity groups in any parity. However, for mated gilts and sows the actual culling intervals were at least 30 d longer than the guideline culling intervals (P < 0.05). Guideline and actual culling intervals for mated gilts and sows were at least 10 d shorter in high-performing herds than in low-performing herds (P < 0.05). High-performing herds had lower proportions of sows culled after the second reservice than intermediate- or low-performing herds in parity groups 0 to 5 (P < 0.05). In conclusion, culling guidelines for mated sows differed between herd productivity groups, and culling guidelines for mated gilts and sows were not strictly followed in any herd group in the commercial herds. [ABSTRACT FROM AUTHOR]

The article presents a study which analyzed sow lifetime performance and by-parity performance of swine herds. The authors used a 3 by 3 factorial design in their study, which focused on 101 Japanese herds that totals 173,526 parity records of 34,929 sows from 2001-2006. Three groups were made from the total sows based on the lower and upper 25th percentiles of annualized lifetime pigs born alive. The authors observed that a decrease from parity 1 to 5 was present in the number of pigs born alive of lifetime efficiency (LE) sows. It concludes that performance pattern of LE sows showed a fall in the number of pigs born alive across parity.

The article discusses a study on the link between the age of gilts at first mating (AFM) and the lifetime performance and risk of culling in commercial herds. In the study, AFM and reproductive performance by parity between three herd groups were compared. The lifetime nonproductive days (NPD) and the number of pigs born alive (PBA) were calculated for female pigs. The study found fewer PBA in female animals with an AFM of 209-229 days. Herds with the highest performance showed about two week earlier AFM. The authors recommend to implement herd management practices that raise the proportion of gilts with a lower AFM within a herd.

The article presents a study regarding the measurement of the percentage of pigs born dead in the number of total pigs born (PPBD) and the connection of PPBD to total pigs born by parity and herd groups. The study used 236,805 parity records of 51,553 sows in 110 herds. It adds that the herd groups include high-, intermediate-, and low-performing herds which were based their upper and lower 25th percentiles of PWMFY. Linear mixed-effects were made for the analysis of the data of swine. The results show that when the total pigs born increase, PPBD also increase in all the parity groups. The study concludes that management of farrowing improve sows PPBD in parity three and higher.

The article presents a study which examines the importance of number of matings and services, which include single or more matings of a sow during a 10-day estrus period, in the reproductive performance in high-performing and ordinary swine herds. The reproductive performance of the female pigs was analyzed using mixed-effects models. Results reveal that triple or more-mated (TM) sows had 3.5% higher pigs born alive (PBA) rates than doubled-mated (DM) ones. It also shows that high-performing herds with single mating, DM, and TM have relative frequencies of 3.4%, 27.4% and 69.2%, while 4.6%, 59.3% and 36.1% in ordinary herds, respectively. It is ideal for first-serviced females to perform TM than DM which are more suitable among reserviced females.

The article presents a study that investigates the connection of single-mating occurrences (SMO) with farrowing rate and pigs born alive (PBA) in first-serviced and reserviced female pigs, and to determine the factors linked with SMO on commercial farms. The study analyzed data which include 91,233 farrowing and 11,334 service records on 117 farms. The results showed that higher SMO are apparent to reserviced females than first-serviced females, may be partially due to the different patterns of luteinizing hormones (LH) between first-serviced females and reserviced females. Moreover, it reveals that the key for improving reproductive performance in both first-serviced and reserviced females is the practice of multiple mating.

The article presents study which evaluates the effect of increased lactation length (LL) on the reproductive efficiency of sows in commercial herds. Study shows an interaction between LL and the herd groups for estimated pigs born alive per farrowed sow per year (PBASY). It was found out that the high-performing herds' estimated PBASY did not increase as LL increased. It points out that the estimated litters per farrowed sow per year (LSY) declined by 0.19 as LL increased from 14-28 days. This suggests that increased LL may not decrease sow performance in high-performing herds.

The article presents study which identifies by-parity nonproductive female days (NPD or NPDs) as well as mating and culling measurements of female pigs in commercial breeding herds in the U.S. The study aims to determine herd productivity measurements and compare by-parity NPDs between three herd groups with different reproductive productivities. It shows that the monitor of by-parity NPD and mating and culling measurements is good in herd productivity improvement. It recommends the use of by-parity measurements in three herd groups.

Abstract: The objectives of this study were to investigate the associations of weaning-to-first-mating interval (WMI) groups with reproductive performance, to determine the repeatability and the correlation coefficients in WMI groups between consecutive parities, and to investigate factors associated with the proportion of sows having WMI 4–6 days. This study was conducted using 55,690 parity records of 11,991 sows born during 1999 in 94 herds. Five groups of WMI were formed: 0–3, 4–6, 7–20, 21–27, and ≥28 days. The correlation and the repeatability of the WMI groups were determined using correlation analysis and variance component analysis. Mixed-effects models were used to analyze the associations of WMI groups with reproductive performance, and the associations of parity, lactation length (LL), and nursing piglets with the proportion of sows having WMI 4–6 days. The overall proportion of the WMI 4–6 days was 82.3%. Sows with WMI 4–6 days had the highest farrowing rate, and had more pigs born alive than those with WMI 7–20 days (P <0.01). At each farrowed parity, sows with WMI 4–6 days had higher parity at removal than those with WMI 7–20 days (P <0.01). The repeatability of the WMI groups was low (0.08), and the correlation coefficients of WMI groups between consecutive parities were also low (0.10≤ r ≤0.18; P <0.01). More than 85.9% of sows with WMI 4–6 days were mated on 4–6 days postweaning at subsequent parity. Meanwhile, 65.8–83.9% of sows with WMI 0–3 or ≥7 days were also mated on 4–6 days postweaning at subsequent parity. Additionally, sows with parity ≥2, LL 24–28 days, and 9–10 nursing piglets were more likely to have WMI 4–6 days (P <0.01). In conclusion, sows having any WMI were more likely to be mated on 4–6 days postweaning at subsequent parity, and sows mated on 4–6 days had higher reproductive performance and higher longevity. Increased LL may increase the proportion of sows having WMI 4–6 days. [Copyright &y& Elsevier]

Investigates the effects of gestational energy intake on glucose tolerance in late gestation and midlactation, luteinizing hormone characteristics during lactation and postweaning in swine. Individual gestation stall for pregnant gilts; Conduction of glucose tolerance test; Analysis of plasma concentrations; Serum concentrations; Analysis by Greater Linear Method.

Our objectives in this review are 1) to define the four components of sow lifetime performance, 2) to organize the four components and other key measures in a lifetime performance tree, and 3) to compile information about sow and herd-level predictors for sow lifetime performance that can help producers or veterinarians improve their decision making. First, we defined the four components of sow lifetime performance: lifetime efficiency, sow longevity, fertility and prolificacy. We propose that lifetime efficiency should be measured as annualized piglets weaned or annualized piglets born alive which is an integrated measure for sow lifetime performance, whereas longevity should be measured as sow life days and herd-life days which are the number of days from birth to removal and the number of days from date of first-mating to removal, respectively. We also propose that fertility should be measured as lifetime non-productive days, whereas prolificacy should be measured as lifetime pigs born alive. Second, we propose two lifetime performance trees for annualized piglets weaned and annualized piglets born alive, respectively, and show inter-relationships between the four components of the lifetime performance in these trees. Third, we describe sow and herd-level predictors for high lifetime performance of sows. An example of a sow-level predictor is that gilts with lower age at first-mating are associated with higher lifetime performance in all four components. Other examples are that no re-service in parity 0 and shorter weaning-to-first-mating interval in parity 1 are associated with higher fertility, whereas more piglets born in parity 1 is associated with higher prolificacy. It appears that fertility and prolificacy are independent each other. Furthermore, sows with high prolificacy and high fertility are more likely to have high longevity and high efficiency. Also, an increased number of stillborn piglets indicates that sows have farrowing difficulty or a herd health problem. Regarding herd-level predictors, large herd size is associated with higher efficiency. Also, herd-level predictors can interact with sow level predictors for sow lifetime performance. For example, sow longevity decreases more in large herds than small-to-mid herds, whereas gilt age at first-mating increases. So, it appears that herd size alters the impact of delayed gilt age at first-mating on sow longevity. Increased knowledge of these four components of sow lifetime performance and their predictors should help producers and veterinarians maximize a sow's potential and optimize her lifetime productivity in breeding herds. [ABSTRACT FROM AUTHOR]

Abortion occurrences disturb the projected production volume and increase non-productive days of female pigs. The objectives of the present study were (1) to define abortion occurrences including abortion rate and abortion risk, (2) to examine risk factors that were associated with abortions, (3) to determine repeatability of abortions and (4) to compare reproductive performance between aborting and non-aborting re-serviced female pigs. Datasets included 122,935 lifetime performance records and 630,363 mating performance records of females in 125 herds between 2008 and 2013 in Spain, Portugal and Italy. Annualized abortion rate was defined as the number of abortion records divided by the sum of the reproductive herd life days×365 days×100. Abortion risk per service was defined as the number of abortion records divided by the number of service records×100. Generalized linear models with random herd effect were applied to the data. Annualized abortion rate (±SE) and abortion risk per service were 3.0±0.05 and 1.2±0.01%, respectively. Factors for an increased abortion risk per service were parity 0 or parity 5 or higher, re-servicing, servicing in July and August, delivering stillborn fetuses in a previous litter and having prolonged weaning-to-first-mating interval (WMI; P <0.05). Gilts (parity 0) and sows in parity 5 or higher had 0.3% higher abortion risk than parity 1 sows ( P <0.05). Re-serviced females had 0.5% higher abortion risk than first-serviced females ( P <0.05). Females serviced in July and August had 0.4–0.5% higher abortion risk than those serviced in March and April ( P <0.05). Sows that had previously delivered stillborn fetuses subsequently had 0.1% higher abortion risk than those that had no stillborn fetuses ( P <0.05). Sows mated 7 days or more after weaning had 0.2% higher abortion risk than those mated 0–6 days after weaning ( P <0.05). Of the 7187 females that had aborted once, 4.1% experienced a second abortion in the same or a later parity. The repeatability of abortions was estimated to be 24.3–24.4%. Females that were reserviced after aborting had 0.6 lower total number of piglets born than re-serviced females that had not aborted ( P <0.05). However, there was no difference in farrowing rate or WMI between aborting and non-aborting re-serviced females ( P ≥0.11). It is recommended that producers closely monitor female pigs at risk of having an abortion in order to reduce non-productive female days. [ABSTRACT FROM AUTHOR]

Abstract: The objectives of this study were to assess the occurrence of decreased numbers of pigs born alive (PBA) in parity 2 (D-PBA) and to evaluate the importance of D-PBA sows and herds by analyzing against using the summed numbers of PBA in parity 1 and 2 (SPBA) and nonproductive sow days (NPD). The study assessed annual data from 2001 to 2005 from 106 herds, and sow data including 137,360 farrowing records of 68,680 sows farrowed in parity 1 and 2. D-PBA was defined as the same or fewer numbers of PBA in parity 2 than that in parity 1 at either the sow or herd level. Sows or herds were categorized into two groups: D-PBA or increased PBA in parity 2 (I-PBA). NPD was defined as the number of days that sows were neither gestating nor lactating in parity 1. Mixed-effects models were used to compare the reproductive performance between the two groups. Of the 68,680 sows, 49.5% had an occurrence of D-PBA. D-PBA sows had 0.3 pigs fewer SPBA than I-PBA sows, but those sows had 1.9days shorter NPD in parity 1 than I-PBA sows (P <0.05). Over the five years studied the average annual proportion of D-PBA herds was 16%. No differences were found between the D-PBA and I-PBA herds in the number of pigs weaned per mated female per year (PWMFY), SPBA or NPD in any year. Additionally, the PWMFY was not correlated in any years with either the proportions of D-PBA sows or the difference in PBA between parity 1 and 2. In conclusion, the occurrence of D-PBA does not appear to be a serious problem in Japanese swine herds studied. [Copyright &y& Elsevier]