Non-productive Days Research Articles

Factors associated with the productive longevity of sows in commercial breeding herds

Abstract. Maximizing sows' productive longevity (PL) represents a significant challenge faced by the swine industry, as the growing increase in the removal rate of sows, mainly young sows, directly impacts the system's economy. In addition, there are ethical concerns associated with animal welfare issues due to the low PL of sows. The objective of this study was to identify and evaluate the risk factors influencing the removal of sows from commercial swine production systems. The variable of interest was the PL of sows. The PL was modeled using Cox regression analysis to identify the factors that affected this variable. The factor with the greatest contribution to PL was sow type (ST), followed by the return to estrus percentage (REP), herd size (HS), season, lactation duration, weaning–estrus interval (WEI), piglets born alive, mummy percentage, and total piglets born. The removal risk was higher for hyperprolific sows than for normal sows. According to the nonproductive day (NPD) variable (an indicator that considers REP and WEI in its calculation), sows with more than 60 nonproductive days per year are at higher risk of elimination. The risk of removal was higher for sows from large herds than for sows from medium or small herds. The PL of sows within a herd is determined by the type of sow and the sows' association with environmental disturbances, including climatic factors (artificial climate control), management practices (human resources), and economic resources (size and infrastructure).

PSI-3 Effect of feed and water consumption patterns during the lactation period on wean-to-estrus interval in weaned sows

Abstract There is sufficient evidence that adequate feed and water consumption during the lactation period positively influences sow body condition at weaning. Optimum body condition score after the lactation period decreases sow wean-to-estrus interval and non-productive sow days and promotes sow reproductive performance in the following reproductive cycle, in general. However, feed and water intake patterns have not been extensively studied in commercial sow research; thus, the objective of this study was to determine the effect of feed and water consumption patterns in the lactation period on wean-to-estrus interval in weaned sows. This trial was conducted in a commercial sow farm located in southwestern Minnesota in March 2023. Each lactation feeder was outfitted with a MealMeter 2.0 device (PigEasy, LLC, Templeton, IA), which uses a rotating feed dispenser to release feed ad libitum at the request of each sow. In addition, the MealMeter 2.0 device utilizes sensors to track the number of times feed and water were accessed at 15-min time intervals across the entire lactation period. Average daily feed (ADF) and water accessions (ADW) were summarized for each sow during the lactation period (n = 84 sows). Root mean squared error (RMSEF and RMSEW for feed and water accessions, respectively) was calculated from the residuals of the regression between days post-farrowing and ADF and ADW for each sow and was considered a measure of variation in feed and water accessions during the lactation period. Moreover, the number of days from weaning to the first estrus was recorded and defined as the wean-to-estrus interval (WTE). Due to the distribution of WTE, sows with a WTE ≤ 5 d and WTE > 5 d were separated into a binary classifier (0 = WTE ≤ 5 d and 1 = WTE > 5 d). The relationship between each feed and water measurement and WTE class was estimated using a logistic regression model fit with R Statistical Software. Average daily feed and water accessions were negatively associated with WTE class (P- = 0.07 and 0.04, respectively; Table 1), indicating that as feed and water accessions increase, the probability of observing a WTE greater than 5 d decreases. In addition, RMSEF and RMSEW were also negatively associated with WTE class, which suggests that as the variation in each measure across the lactation period increases, the probability of observing a WTE greater than 5 d is reduced. This result was not expected and, thus, requires further investigation. Nonetheless, results from this study suggest that the mean and variation of daily feed and water accessions are associated with WTE and sufficient consumption of nutrients during the lactation period is critical to reducing the number of days to first estrus in weaned sows.

Resumption of production operations during the silent disposal period of African swine fever outbreaks: a case study

BackgroundBatch production, a widely implemented production model in large-scale pig farms, was characterized by its long-term duration, cost-effectiveness, and efficiency. Nevertheless, the recent occurrence of African swine fever (ASF) outbreaks in China has necessitated the implementation of discreet mating operations within this model, leading to disruptions in production cycles and substantial indirect losses.Case presentationThis study implemented a novel operational procedure, which involved the division of risk areas for zone management and allowed mating operations, in 12 farms experiencing ASF outbreaks. Another 12 farms were used as a control group, employing the old procedure. Subsequently, the prognoses of both the old and new procedures were calculated and analyzed. The findings indicate that the new method resulted in an enhanced retention rate and reduced non-productive days (NPD), without impacting the positive detection rate and disposal time. Consequently, this approach significantly mitigated economic losses (p < 0.05).ConclusionThe efficacy of the novel procedure in mitigating the indirect economic losses stemming from ASF outbreaks, through the reduction of NPD while maintaining retention rates and disposition days, has been substantiated. This methodology has demonstrated feasibility in extensive pig farming operations and exhibits promise for broader application.

ASSOCIATIONS BETWEEN FIRST PARITY WEAN-TO-SERVICE INTERVAL AND SOW LIFETIME PRODUCTIVITY TRAITS

&lt;p&gt;&lt;strong&gt;Background: &lt;/strong&gt;Sows’ lifetime reproductive performance is a key component for farm productive efficiency and profitability. &lt;strong&gt; Objective:&lt;/strong&gt; To investigate associations between first parity wean-to-service interval (WSI) and sows’ lifetime reproductive performance traits. &lt;strong&gt;Methodology:&lt;/strong&gt; Data were collected in a 3,900-sows farrow-to-finish farm in Yucatan, Mexico. Lifetime productivity records included parity number at culling (NCP), lifetime number piglets born alive (LNBA) from parity two until culling, lifetime non-productive days (LNPD) and length of productive life (LPL) for 4,175 sows. Association between WSI and sow lifetime productivity traits were analyzed using general linear models, including year and season at first service as categorical fixed effects and WSI as linear and quadratic predictor. Cut-off values for WSI were estimated using regression trees analysis. &lt;strong&gt;Results:&lt;/strong&gt; WSI was negatively associated (&lt;em&gt;P&lt;/em&gt; &amp;lt; 0.05) with LNBA and NCP, positively (&lt;em&gt;P&lt;/em&gt; &amp;lt; .05) with LNPD and non-associated with LPL (&lt;em&gt;P &lt;/em&gt;&amp;gt; 0.05). Cut-off values for WSI varied for each predicted variable: WSI &amp;gt; 5 days would translate into longer 13 more days of LPL, WSI &amp;lt; 7 days would increase LNBA by two extra pigs, WSI ≥ 9 days increase NCP by 0.2 parities and WSI &amp;lt;10 days would mean 24 fewer LNPD. &lt;strong&gt;Conclusions:&lt;/strong&gt; Under the conditions of this study, shorter WSI were associated with improved lifetime productivity traits, confirming the importance of traits observed early in life as indicators of performance in subsequent parities.&lt;/p&gt;

Machine learning based personalized promotion strategy of piglets weaned per sow per year in large-scale pig farms

BackgroundThe purpose of this study was to analyze the relationship between different productive factors and piglets weaned per sow per year (PSY) in 291 large-scale pig farms and analyze the impact of the changes in different factors on PSY. We chose nine different algorithm models based on machine learning to calculate the influence of each variable on every farm according to its current situation, leading to personalize the improvement of the impact in the specific circumstances of each farm, proposing a production guidance plan of PSY improvement for every farm. According to the comparison of mean absolute error (MAE), 95% confidence interval (CI) and R2, the optimal solution was conducted to calculate the influence of 17 production factors of each pig farm on PSY improvement, finding out the bottleneck corresponding to each pig farm. The level of PSY was further analyzed when the bottleneck factor of each pig farm changed by 0.5 standard deviation (SD).Results17 production factors were non-linearly related to PSY. The top five production factors with the highest correlation with PSY were the number of weaned piglets per litter (WPL) (0.6694), mating rate within 7 days after weaning (MR7DW) (0.6606), number of piglets born alive per litter (PBAL) (0.6517), the total number of piglets per litter (TPL) (0.5706) and non-productive days (NPD) (− 0.5308). Among nine algorithm models, the gradient boosting regressor model had the highest R2, smallest MAE and 95% CI, applied for personalized analysis. When one of 17 production factors of 291 large-scale pig farms changed by 0.5 SD, 101 pig farms (34.7%) can increase 1.41 PSY (compared to its original value) on average by adding the production days, and 60 pig farms (20.6%) can increase 1.14 PSY on average by improving WPL, 45 pig farms (15.5%) can increase 1.63 PSY by lifting MR7DW.ConclusionsThe main productive factors related to PSY included WPL, MR7DW, PBAL, TPL and NPD. The gradient boosting regressor model was the optimal method to individually analyze productive factors that are non-linearly related to PSY.

Equine chorionic gonadotropin pretreatment 15 days before fixed-time artificial insemination improves the reproductive performance of replacement gilts

Fixed-time artificial insemination (FTAI) technology uses exogenous reproductive hormones to regulate the sexual cycle and ovulation of sows without oestrus identification, which improves the sow breeding utilisation rate, reduces the number of non-productive days, and elevates the efficiency of pig farm management. In this study, we aimed to optimise FTAI procedures. Healthy 190-day-old and about 90 kg Large White × Landrace crossing breed replacement gilts (n = 166) which were of unknown reproductive status were randomly selected and divided into three groups: a control group (n = 62), an eCG-15D group in which the gilts were pretreated with equine chorionic gonadotropin (eCG) injection 15 days before starting FTAI (n = 50), and an eCG-20D group pretreated with eCG injection 20 days before starting FTAI (n = 54). All three groups were then subjected to the same conventional FTAI procedure. Pigs were orally administered Altrenogest (ALT, 20 mg per pig per day) for 18 days and then 42 h after ALT feeding was stopped, they were injected with 1 000 IU eCG followed by 100 μg GnRH 80 h later. The gilts were inseminated for the first time 24 h after gonadotropin-releasing hormone (GnRH) injection and then again 16 h later. After 42 h of ALT feeding, gilts in the eCG-15D group displayed a higher follicular diameter until artificial insemination (AI) than those from the other groups (P < 0.05). In addition, the ovulation times were the most synchronised in the eCG-15D group, with 100% of the gilts ovulating before the second AI on day 25 of FTAI. Furthermore, the gilts in the eCG-15D group achieved the highest pregnancy rate (92%), farrowing rate (90%), total pigs born (11.59), and pigs born alive (11.18). Together, the findings of this study demonstrate that reproductive performance can be optimised by pretreating gilts with eCG 15 days before conventional FTAI.

PSII-7 Farrowing age is a predictor of sow lifetime performance

Abstract Sow lifetime performance can be predicted by sow performance at an early age; however, few studies have examined the relationship between farrowing age (FA) after parity 1 and sow lifetime performance. Therefore, our objective was to examine the association between FA in different parities and sow lifetime performance. Data were extracted from 198,043 sows entered into 155 Spanish herds between 2011 - 2013 and removed between 2011 - 2016. The 1st to 99th percentiles of FA records were analyzed, with FA defined as the number of days from birth to the farrowing date in each parity. A two-level linear mixed-effects model was applied to examine the relationship between FA and lifetime performance of sows (SAS University Edition). Means of FA + SD (range) in parities 1 and 3 were 368.4 + 34.8 (238 - 460) days and 663.5 + 41.4 (501 - 773) days, respectively. The ranges of FA in parity 1 and 3 were 238 - 460 days and 501 - 773 days, respectively. Lifetime performance decreased with higher FA in both parities. For example, in parity 1, as FA increased from 290 to 410 days, lifetime piglets born alive (PBA) decreased by 4.4 piglets, annualized lifetime PBA decreased by 3.5 piglets and nonproductive days increased by 16.8 days. Similarly, in parity 3, as FA increased from 590 to 710 days, lifetime PBA decreased by 5.3 piglets, annualized lifetime PBA decreased by 3.0 piglets and nonproductive days increased by 39.5 days. Also, sows with a lower FA in parity 1 had fewer PBA in that parity than sow with a higher FA (P &amp;lt; 0.05). However, they also had fewer nonproductive days and a shorter weaning-to-first-mating interval and more annualized lifetime PBA. Therefore, these data indicate that FA can be used to predict lifetime performance of the sows.

PSII-11 Herd size associated with sow lifetime performance in Spanish breeding herds

Abstract It is critical for producers to maximize sows’ reproductive potential in commercial herds in order to improve economic efficiency. While it is generally known that large herds have better reproductive performance than small herds, few studies have assessed how much the lifetime reproductive performance of sows is associated with herd size. Therefore, our objective was to examine the relationship between six herd size groups and sow lifetime performance. Data were extracted from 166,335 sows which were entered into 155 Spanish breeding herds from 2011 - 2013 and removed by 2017. Herds were categorized into six groups based on the 10th, 25th, 50th, 75th and 90th percentiles of average sow inventory in 2016: 87 - 195, 196 - 342, 343 - 596, 597 - 1,025, 1,026 - 2,152 and 2,153 - 3,669 sows. A two-level linear mixed-effects model was applied to examine the relationship between herd size and reproductive performance of sows (SAS University Edition). No differences were found between herd size groups and either lifetime total born or lifetime piglets born alive. However, the largest herd group had 23.0 fewer lifetime nonproductive days (NPD), and 2.1 more annualized lifetime piglets weaned than the mid-size (343 - 596 sows) herds (P &amp;lt; 0.05). Also, parity at removal was 0.3 lower in the largest herds than the mid-size herds (P &amp;lt; 0.05). Furthermore, the largest herds also had 0.8 - 1.0 days shorter weaning-to-first-mating interval (WMI), 2.8 - 4.9% higher farrowing rates and 10.2 - 11.9 days shorter repeat intervals than the mid-size herds (P &amp;lt; 0.05). In conclusion, the shorter WMI, fewer NPD and improved reproductive productivity in the largest herds suggest that these herds have better lactational management and quicker culling decision making than mid-size herds.

How much the reproductive losses of sows can be impacting the carbon footprint in swine production?

Animal production influences the environment through land-use changes and the cycle of nutrients such as CO2. Pork production is an essential sector of agribusiness nowadays. This type of farming will also be affected by climate change since the production of animal feeds depends on the weather. New information on pork production is vital to study the amount of feed wasted through sow yield and environmental inefficiency on farms. Many sow indexes have been used in the last years, especially addressing reproduction efficiency. However, there is a lack of research on production losses from Greenhouse Gas emissions. The aim of the assessment was to estimate the daily feed intake of sows and the amount of feed consumed during their nonproductive days, correlating these results to greenhouse gas emissions. The variables were analyzed by the Life Cycle Assessment tool at Tier 3 level. The physiology of metabolic digestion related to sow respiration was calculated for each life stage. There were six Brazilian scenarios: 1 and 2 – farms from the Midwest region; 3 to 6 – different piglets systems from all regions. Producing piglets with 6.0 to 10.0 kg requires much time and feed intake, and feed processing depends on natural resources. Daily feed intakes during nonproductive days corresponded to 16,315.30 tons of total feed intake/year. Each scenario showed different results. For instance, Scenario 1 emitted 2.80 kg of CO2eq./kg of piglet, and Scenario 4 emitted 3.89 kg of CO2eq./kg of piglet. The environmental impacts analyzed lead us to conclude that the Brazilian production can be more efficient. Nonproductive days were harmful for weaned piglet production as the total feed intake of sows correlate with born alive and weaned piglets. Greenhouse Gas emissions can be included in sows yield calculation.

Mixing aggression intensity is associated with age at first service and floor type during gestation, with implications for sow reproductive performance

Aggression resulting from mixing to establish a dominance hierarchy is a major welfare concern for group-housed sows. The associated stress can negatively impact aspects of reproductive performance. Objectives of this study were to investigate associations between 1) age at first service (AFS) and mixing aggression intensity in first parity sows, 2) mixing aggression intensity and reproductive performance within and between parity one and parity two, and 3) mixing aggression intensity, floor type during gestation and reproductive performance. Gilts (n =160, hereafter referred to as sows) were mixed into stable groups of eight unfamiliar individuals approximately 4 days after artificial insemination, housed on fully slatted concrete (CON; n =80) floor uncovered or covered with rubber slat mats (RUB; n =80), and followed through two parities. Skin lesions (SLMIX; a proxy for the intensity of mixing aggression), were scored post mixing in each parity according to severity (0=no lesions to 5=severe lesions) on five body regions (ear, neck, hindquarter, rump, and belly) on the left and right sides, and at the tail/anogenital region. Total SLMIX score was calculated for each sow. Data on reproductive performance traits were acquired retrospectively from farm records for both parities. Two analyses were performed: 1) data from each parity were analysed separately and 2) SLMIX score in parity one was used to predict reproductive performance in parity two. Lower AFS was associated with a lower SLMIX score in parity one (P =0.031). There was no association between SLMIX score and reproductive performance in parity one, while sows with higher SLMIX score in parity two had a higher proportion of piglets dead during lactation (P =0.027) and a longer cycle length (P =0.003) in parity two. Sows with higher SLMIX scores in parity one had more non-productive days (P <0.001) in parity two. Concrete sows had a higher SLMIX score than RUB sows in parity one (P =0.015), but not in parity two. In addition, CON sows had a higher proportion of piglets born dead (P =0.013) compared with RUB sows in parity two. Mixing aggression has a negative influence on reproductive performance within parities, and it may also have a long-term negative carry-over effect on reproductive performance in subsequent parities. Serving gilts at younger ages could help to minimize the intensity of aggression at mixing, while housing on rubber flooring has beneficial implications for their reproductive performance.

7 Mixing aggression and floor type during gestation have implications for sow reproductive performance

Abstract Aggressive behavior resulting from mixing to establish a dominance hierarchy is a welfare concern for group-housed sows. The associated stress could negatively impact reproductive performance (RP). Objectives of this study were to investigate associations between 1) mixing aggression intensity and RP within and between parities one (P1) and two (P2), and 2) aggression intensity, floor type and RP. A total of 164 gilts were followed through two parities. Gilts were mixed into stable groups of eight unfamiliar individuals four days after insemination, and housed on fully-slatted floors, either uncovered (CON; n = 84) or covered (RUB; n = 80) by a rubber slat-mat until farrowing (for both parities). Skin lesion scores (SLS) (proxy for mixing aggression intensity), were recorded 24–72 hrs post-mixing (0 = no lesions to 5 = severe lesions) on five body regions on left and right sides, and on the tail, in both parities. Total SLS was calculated for each sow. RP data were retrospectively acquired from farm records for both parities. Data were analyzed using GLMM in PROC GLIMMIX of SAS (v9.4) where 1) each parity analyzed separately, and 2) SLS in P1 used to predict RP in P2. Gilts with higher SLS in P2 had higher piglet mortality (P = 0.021) and longer cycle length (P = 0.003) in P2. Gilts with higher SLS in P1 had more non-productive days (P &amp;lt; 0.001) in P2. CON gilts had higher SLS than RUB gilts (P = 0.017) in P1, but not in P2 (P &amp;gt; 0.05). CON gilts also had more piglets born dead (P = 0.004) and tended to crush more piglets (P = 0.097) in P2. Our results confirm that mixing aggression impacts RP in the current parity negatively. They also suggest that mixing aggression experienced by gilts may have long-term negative carry-over effects on performance in subsequent parities. Use of rubber flooring appears to mitigate detrimental effects of mixing aggression, perhaps through improved sow comfort.

273 Impact of either high energy or high SID Lys:ME on Parity 1 performance in lactation

Abstract Primiparous sows may have difficulty consuming sufficient feed during lactation to account for energy lost in milk production, development, and body maintenance. Addition of higher energy and/or higher standardized ileal digestible (SID) Lys may improve gilt and litter performance. One hundred seventy-two primiparous DNA F1 females were randomly allotted within breeding/farrowing group, previous treatment, and entry weight at farrowing to one of four dietary treatments. Treatments were arranged in a 2 x 2 factorial with energy (3186 and 3332 kcal/kg ME) and SID lysine (1.15 and 1.30%). Sows were weighed upon entry and exit of the farrowing room. Feed disappearance was calculated as the total amount of feed provided to the sow during lactation. A post-farrow weight model was utilized to assess true weight loss in lactation. Litters were standardized within 24 h of birth, and individual pig birth and weaning weights were recorded. The wean to estrus interval was also measured. Data were analyzed as a randomized complete block design with the fixed effect of treatment and the random effect of replicate. Addition of high energy and/or high lysine did not impact (P &amp;gt; 0.10) piglet wean weight or sow average daily feed intake. High energy diets reduced (P &amp;lt; 0.05) sow weight loss post-farrow by 15.5% from 8.75 to 7.39 kg. High SID lysine diets reduced (P &amp;lt; 0.05) number of sows not expressing estrus by day 9 post-wean from 13.0 to 7.7% of sows eligible for insemination. The high SID lysine diets targeted 70 g/d and led to an increase (P &amp;lt; 0.05) of 10.3% of sows displaying estrus on day 4 and 5. These data show that higher levels of SID lysine to target 70 g/d in lactation can improve wean to estrus interval, and potentially decrease non-productive sow days.

Herd-level factors associated with non-productive days and farrowing rate in commercial pig farms in two consecutive years

Non-productive days (NPD) and farrowing rate (FR) are indicators related to the number of piglets weaned per sow per year. Identifying the factors that affect these two indicators can improve the productivity and profitability of pig production. The objective of this study was to identify and quantify the associations of some factors related to the performance, management, facilities, feeding, health, and biosafety on NPD and FR over two consecutive years, using an inquiry applied to commercial pig farms in Brazil. Data from 150 farms were collected for a total study population of 135 168 sows, including gilt replacement, breeding (mating), gestation and farrowing/lactation phases. A questionnaire focusing on reproductive performance (for the years 2014 and 2015), management, facilities, feeding, health, and biosafety was administered. Multiple regression models were used to assess associations (α = 0.05) between factors and NPD and FR. An increased abortion index was associated with higher NPD (2014) and reduced FR (2014 and 2015); an increase in stillbirths was associated with higher NPD (2014 and 2015), and increased sow mortality was associated with a reduction in FR (2014 and 2015). In addition, farms had lower NPD in 2014, as the sows were younger at first farrowing, and when they had no lined ceiling in the gestation barns. Farms had lower NPD in 2015 when gilts were mated with an average weight of ≤139 kg compared to farms that mated gilts with an average weight >139 kg. Farrowing rate in 2014 was better in farms that fed pregnant sows with liquid/soup diets rather than mash or pelleted diets. Farms with higher FR in 2015 had wet-dry feeders in the farrowing barns rather than separate feeders and drinkers; they also practiced all-in/all-out management in farrowing rooms rather than continuous management. Several factors affect NPD and FR, but in general these factors do not remain the same over the years. Particular attention should be given to reducing abortions, stillborn piglets and the mortality of sows.

Removal of sows in Spanish breeding herds due to lameness: Incidence, related factors and reproductive performance of removed sows

Lameness is a major reason for sow removal in breeding herds. Increased removal occurrences for lameness decrease reproductive efficiency and increase welfare concerns. Therefore, the objectives of this study were to estimate the incidence rate of removal due to lameness, and to investigate the longevity and reproductive performance of sows removed due to lameness. Poisson regression models were applied to a cohort dataset of 137,907 sows in 134 herds located in Spain. The Wilcoxon rank sum test was used to compare the performance of sows removed due to lameness and their controls in one-to-two matched case-control datasets. Removal due to lameness accounted for 4.3 % of all removed sows, and the incidence rate was 19.6 cases per 1000 sow-years (95 % confidence interval: 15.03, 25.51). The majority (70.4 %) of those removed were farrowed sows, whereas only 29.6 % were serviced sows. In farrowed sows, a higher incidence of removal due to lameness was associated with weeks 4–9 after farrowing, higher parity and winter farrowing (P < 0.01). The removal incidence was 24.7–33.1 times higher in weeks 4–9 after farrowing than during the first week after farrowing (P < 0.01). It was 1.3–1.6 times higher in parity 4−5 than in parity 1, and 1.3 times higher for winter farrowing than for summer farrowing (P < 0.01). In contrast, the factors associated with removal due to lameness with serviced sows were weeks 4−5 after service and being re-serviced (P < 0.01). The service sow removal incidence was 4.7 times higher in weeks 4−5 after servicing than during the first 2 weeks after servicing (P < 0.01). Also, it was 2.2 times higher in re-serviced sows than in first serviced sows (P < 0.01). However, removal in serviced sows was not associated with parity (P = 0.10) or service season (P = 0.39). In the case-control datasets, the sows removed due to lameness had higher weaning-to-first-mating interval (means: 6.5 vs. 5.8 days), fewer piglets born alive (11.7 vs. 12.5 piglets) and lower parity at removal (3.4 vs. 4.9; P < 0.01) than sows removed for other reasons or non-removed sows. However, there was no difference in gilt age at first service between the case and control groups (P = 0.29). We recommend identifying sows showing early signs of lameness and treating them with pain medication until removal. The best time for removal would be at weaning when non-productive sow days start.

Increased age at first-mating interacting with herd size or herd productivity decreases longevity and lifetime reproductive efficiency of sows in breeding herds

BackgroundOur objectives were to characterize sow life and herd-life performance and examine two-way interactions between age at first-mating (AFM) and either herd size or herd productivity groups for the performance of sows. Data contained 146,140 sows in 143 Spanish herds. Sow life days is defined as the number of days from birth to removal, whereas the herd-life days is from AFM date to removal date. Herds were categorized into two herd size groups and two productivity groups based on the respective 75th percentiles of farm means of herd size and the number of piglets weaned per sows per year: large (> 1017 sows) or small-to-mid herds (< 1017 sows), and high productivity (> 26.5 piglets) or ordinary herds (< 26.5 piglets). A two-level liner mixed-effects model was applied to examine AFM, herd size groups, productivity groups and their interactions for sow life or herd-life performance.ResultsNo differences were found between either herd size or herd productivity groups for AFM or the number of parity at removal. However, late AFM was associated with decreased removal parity, herd-life days, herd-life piglets born alive and herd-life annualized piglets weaned, as well as with increased sow life days and herd-life nonproductive days (P < 0.05). Also, significant two-way interactions between AFM and both herd size and productivity groups were found for longevity, prolificacy, fertility and reproductive efficiency of sows. For example, as AFM increased from 190 to 370 days, sows in large herds decreased herd-life days by 156 days, whereas for sows in small-to-mid herds the decrease was only 42 days. Also, for the same AFM increase, sows in large herds had 5 fewer sow life annualized piglets weaned, whereas for sows in small-to-mid herds this sow reproductive efficiency measure was only decreased by 3.5 piglets. Additionally, for ordinary herds, sows in large herds had more herd-life annualized piglets weaned than those in small-to-mid herds (P < 0.05), but no such association was found for high productivity herds (P > 0.10).ConclusionWe recommend decreasing the number of late AFM sows in the herd and also recommend improving longevity and lifetime efficiency of individual sows.

Environmental factors associated with lifetime non-productive days of sows in Southeastern Mexico

Objetivo. Estimar el número de días no productivos (DNP) de por vida, la proporción de DNP (%DNP) y días no productivos por cerda por año (DNP/Y), y determinar el efecto de factores de hato y cerda sobre las características aquí estudiadas en tres granjas comerciales en el trópico mexicano. Materiales y métodos. Los datos de 6703 cerdas de tres granjas comerciales fueron usados. El modelo que describió las características de interés incluyeron los efectos fijos de granja, año de primer parto, época de primer parto, edad al primer parto, causa de desecho, interacción de año por época y error residual. Resultados. Las medias de DNP de por vida, %DNP y DNP/Y fueron 64 días, 12% y 39.3 días, respectivamente. Todos los factores tuvieron efectos significativos (p&lt;0.01) en todas las características. Las cerdas con primer parto a mayor edad y las eliminadas por razones reproductivas tuvieron más DNP en el hato. Además, las cerdas eliminadas en el primer parto tuvieron menor DNP y mayor %DNP que las cerdas desechadas en partos subsecuentes. Conclusiones. La eliminación temprana de cerdas incrementó la proporción de días no productivos, que a su vez podrían reducir la rentabilidad de las granjas.

Nurse Sows’ Reproductive Performance in Different Parities and Lifetime Productivity in Spain

Our objective was to characterize use of nurse sows in Spanish breeding herds. We analyzed 466 111 parity records and lifetime records of 92 716 sows farrowed between 2011 and 2017 in 69 herds having nurse records. Nurse sows were defined as sows that had weaned 2 or 3 litters in the same lactation period. Mixed-effects models were applied to the data to compare reproductive performance and lifetime productivity between nurse and non-nurse sows. Of all the sows, 6 705 (7.2%) sows served as nurse sows at least once in their lifetime, with 10.2% of the nurse sows having a second nurse event in a later parity. Mean values (SE) of lactation length and number of piglets weaned were 31.0 (0.11) days and 21.9 (0.04) piglets in nurse sows, respectively. Across parities 2-6, nurse sows had 1.9-3.0% greater proportions of weaning-to-first-mating interval 7-20 days than non-nurse sows (P &amp;lt; 0.05). There was no difference between nurse sows and non-nurse sows in farrowing rate in any parity (P &amp;ge; 0.13) and piglets born alive in parities 1-5 (P &amp;ge; 0.15). Also, nurse sows had 3.7-7.4 more annualized lifetime piglets weaned than non-nurse sows (P &amp;lt; 0.01), because nurse sows had similar lifetime non-productive days with non-nurse sows (P &amp;ge; 0.07), but produced 9.3-12.0 more lifetime piglets weaned than non-nurse sows (P &amp;lt; 0.01). Using nurse sows could be a good practice to cope with highly prolific sows.

Determining the optimal age of breeding gilts and its impact on lifetime performance, Literature review

Lifetime sow performance is a critical indicator for producers managing a commercial sow herd. It is comprised of sow longevity, lifetime piglets born alive, lifetime number of pigs weaned and lifetime non-productive sow days. Increased lifetime performance and longevity in sows reduces costs of replacement gilts and improves herd performance and profitability (Sasaki et al., 2008, 2011). One of the most critical factors driving the performance of sow herds is gilt management. Decisions regarding gilts have profound effects on sows’ lifetime performance. Age at first breeding of a gilt is a management decision that has been shown to affect performance and retention of the gilt in a herd.&#x0D; The main aim of this review is to establish factors affecting age of first breeding of gilts and its impact on lifetime performance.

High-performing farms exploit reproductive potential of high and low prolific sows better than low-performing farms

BackgroundOur objective was to examine the impact of farm effects and sow potential on various aspects of sow performance. We examined the interaction between sow prolificacy groups categorized at parity 1 and farm productivity groups for reproductive performance across parities, and lifetime performance. Data included 419,290 service records of 85,096 sows, on 98 Spanish farms, from first-service as gilts to removal, that were served between 2008 and 2013. Farms were categorized into three productivity groups based on the upper and lower 25th percentiles of the farm means of annualized lifetime piglets weaned per sow over the 6 years: high-performing (HP), intermediate-performing (IP), and low-performing (LP) farms. Also, parity 1 sows were categorized into three groups based on the upper and lower 10th percentiles of piglets born alive (PBA) as follows: 15 piglets or more (H-prolific), 8 to 14 piglets, and 7 piglets or fewer (L-prolific). The farm groups represent farm effects, whereas the sow groups represent sow potential. Linear mixed effects models were performed with factorial arrangements and repeated measures.ResultsMean parity at removal (4.8 ± 0.01) was not associated with three farm productivity groups (P = 0.43). However, HP farms had 7.7% higher farrowing rates than LP farms (P < 0.05). As a result, H-prolific and L-prolific sows on HP farms had 29.7 and 30.7 fewer non-productive days during lifetime than the respective sows on LP farms (P < 0.05). Furthermore, the H-prolific and L-prolific sows on HP farms had 4.9 and 6.2 more annualized piglets weaned than respective H-prolific and L-prolific sows on LP farms (P < 0.05), which was achieved by giving birth to 0.8–1.0 and 1.4–1.7 more PBA per litter, respectively, than on HP farms during parities 2–6 (P < 0.05). During the first parity, HP farms had 18.8% H-prolific sows compared to 6.2% on LP farms.ConclusionFarm effects substantially affected lifetime performance of sows. Higher lifetime productivity of sows on HP farms was achieved by higher farrowing rate, fewer non-productive days, more PBA and more piglets weaned per sow, regardless of prolific category of the sows.

Culling in served females and farrowed sows at consecutive parities in Spanish pig herds

BackgroundThe objectives of our study were 1) to characterize culling and retention patterns in parities 0 to 6 in served females and farrowed sows in two herd groups, and 2) to quantify the factors associated with by-parity culling risks for both groups in commercial herds. Lifetime data from first-service to removal included 465,947 service records of 94,691 females served between 2008 and 2013 in 98 Spanish herds. Herds were categorized into two groups based on the upper 25th percentile of the herd means of annualized lifetime pigs weaned per sow: high-performing (> 24.7 pigs) and ordinary herds (≤ 24.7 pigs). Two-level log-binomial regression models were used to examine risk factors and relative risk ratios associated with by-parity culling risks.ResultsMean by-parity culling risks (± SE) for served females and farrowed sows were 5.9 ± 0.03 and 12.4 ± 0.05%, respectively. Increased culling risks were associated with sows that farrowed 8 or fewer pigs born alive (PBA). Also, farrowed sows in high-performing herds in parities 2 to 6 had 1.5–5.6% higher culling risk than equivalent parity sows in ordinary herds (P < 0.05). Furthermore, sows in parities 1 to 6 that farrowed 3 or more stillborn piglets had 2.2–4.8% higher culling risk than for sows that did not farrow any stillborn piglets (P < 0.05). For served sows, culling risk in parity 1 to 6 sows with a weaning-to-first-service interval (WSI) of 7 days or more were 2.2–3.9% higher than equivalent parity sows with WSI 0–6 days (P < 0.05). With regard to relative risk ratios, served sows with WSI 7 days or more were 1.56–1.81 times more likely to be culled than those with WSI 0–6 days.ConclusionProducers should reduce non-productive days by culling sows after weaning, instead of after service or during pregnancy. Also, producers should pay special attention to sows farrowing stillborn piglets or having prolonged WSI, and reconsider culling policy for mid-parity sows when they farrow 8 or fewer PBA.