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Financial impact of average parity of culled females in a breed-to-wean swine operation using replacement gilt net present value analysis
Abstract
of culled females in a breed-to-wean swine operation using replacement gilt net present value analysis. J Swine Health Prod. 2003;11(2):69-74. Summary A net present value (NPV) analysis was used to determine the number of parities a sow must remain in the breeding herd of a breed-to-wean operation before the initial investment in her is profitable, and to evaluate the sensitivity of NPV to produc-tion, price received, and gilt replacement price. On the basis of 1996–2000 average production levels, segregated early weaning (SEW) pig price, production costs, and equity information, a replacement gilt must remain in the breeding herd for three parities before reaching a positive NPV. Sows having a longer productive herd life, when SEW price is at profitable levels, pro-duce a higher NPV, and thus are more profitable investments than females which remain in the herd for shorter periods of time.
... Culling rates in the United States historically have hovered around approximately 50% (Stalder et al., 2004) (Engblom et al., 2016). High replacement rates have resulted in animals that are unable to pay for their initial investment cost (Stalder et al., 2003). Due to the financial impact of culling, many studies have sought to model swine herds to determine economic return and the optimal parity to remove a female from the breeding herd. ...
... Depending on the production system, sows may be voluntarily culled based on breeding programs or involuntarily culled due to unforeseen circumstance. In a net present value analysis that modelled sow culling, it was found that sows do not reach a positive net present value until their third parity (Stalder et al., 2003). Economic models focusing on the production of weaned pigs found that costs were minimized when a sow was between parities five through nine (Gruhot et al., 2017). ...
... However, they reported that for the models base economic and biological variables, culling is financially optimized at four to five parities (Rodriguez-Zas et al., 2006). These conclusions mirror those found in earlier research by Stalder et al. (2003). ...
Early recognition of indicator traits for swine reproduction and longevity supports economical selection decision making. Gilt activity is a key variable impacting a sow’s herd life and productivity. The purpose of this study was to examine early- life behaviors contributing to farrowing traits including gestation length (GL), number born alive (NBA), number weaned (NW), and herd life (HL). Herd life was a binary trait representing if a gilt was culled after one parity. Beginning at approximately 20 weeks of age, video recordings were taken on 480 gilts for 7 consecutive days and processed using the NUtrack system. Activity traits include angle rotated (degree), average speed (m/s), distance travelled (m), time spent eating (s), lying lateral (s), lying sternal (s), standing (s), and sitting (s). Final daily activity values were averaged across the period under cameras. Parity one data was collected for all gilts considered. Data were analyzed using linear regression models and odds ratios (R version 4.0.2). GL was significantly impacted by angle rotated (p = 0.03), average speed (p = 0.07), distance travelled (p = 0.05), time spent lying lateral (p = 0.003), and lying sternal (0.02). NBA was significantly impacted by time spent lying lateral (p = 0.01), lying sternal (p = 0.07), and time spent sitting (p = 0.08). NW was significantly impacted by time spent eating (p = 0.09), time spent lying lateral (p = 0.04), and time spent sitting (p = 0.007). Estimated odds ratios showed gilts traveling below average speeds and spending below average time lying sternal were positively associated with below average GL. Gilts spending below average time lying lateral are associated with below average NW. Gilts spending below average time sitting were negatively associated with below average NW. Gilts spending below average time lying sternal were negatively associated with below average HL. This analysis suggests early-life gilt behavior is associated with sow productivity traits of importance. Further examination of the link between behavior and reproductive traits is necessitated. Utilization of the NUtrack video monitoring system to isolate behavioral differences offers potential to aide in selection decisions. Advisor: Benny Mote
... From an economic standpoint, costs associated with sow mortality can be direct, such as the cost of replacing the dead animals, or indirect, such as opportunity costs (i.e., costs associated with the production deficit resulting from those deaths and the lack of salvage value associated with dead sows). 1 It is estimated that about three to five parities are necessary to achieve an investment return for the producer. 2,3 Still, the annual culling rate ranges from 15% to 93%, with most removals occurring for parity 0 or one females, 4-6 that is, before a positive net present value is achieved. ...
Background:
Sow mortality has become a growing concern in the pig production industry over the past decade. Therefore, we aimed to describe sow mortality and associated factors in a production system in the midwestern USA.
Methods:
Mortality records from 2009 to 2018 for four farrow-to-wean farms were described. Environmental, farm- and individual-level factors associated with weekly mortality and individual risk of dying throughout a sow's lifetime were assessed.
Results:
Deaths occurred at a median of 116 days from last service, or 26 days postpartum. The median parity upon death was two. Overall, the main reasons for death were locomotion (27%) and reproduction (24%). A higher weekly number of deaths was associated with spring (incidence rate ratio [IRR] 1.27, compared to winter). Sows had a higher mortality when they were exposed to at least one porcine reproductive and respiratory syndrome (PRRS) outbreak during their lifetime (IRR 1.55) and when housed in groups (pens) during gestation (IRR 1.32). Conversely, they had a lower mortality when housed in filtered farms (IRR 0.76), accounting for an interaction term between parity at removal and PRRS outbreak exposure.
Limitations:
Issues with data completion and information accuracy were present, and prospective data collection throughout sows' lifetimes is still needed.
Conclusion:
Efforts to reduce infectious diseases within the herd and manage environmental stressors should help reduce mortality.
... This reduces the opportunity for a sow to be sufficiently productive and for a farmer to achieve a profit from the investment in that animal since sows reach peak production between the third and sixth parity and do not produce a profit for the farmer until their third parity. 15 Not only did sows removed for lameness generate fewer total litters in their lifetime, but the proportion of nonproductive days were higher for such sows compared to sows removed for other reasons. There was no difference in the piglets born alive per litter for sows removed for lameness however, there were fewer piglets weaned per litter and a higher piglet mortality rate compared to sows removed for other reasons. ...
Objective: To determine the impact of lameness on sow productivity and longevity and evaluate the effects of housing management on the removal of lame sows in herds using pen gestation. Materials and methods: Retrospective production records and information on housing methods were collected from 23 farms using pen gestation and analyzed for the removal of 214,254 sows from 2014 through 2020. Statistical analyses were performed to evaluate differences in longevity, productivity, and the impact of housing methods. Results: Lameness was the third most reported cause of removal for sows in the study (13.7%). Sows culled for lameness spent significantly fewer days in the herd (P < .001), resulting in fewer litters (P < .001). The odds of removal for lameness were increased by several farm level factors including using dynamic groups and decreasing square footage (P < .05). Implications: Lameness is one of the top 3 reasons reported for sow removal and those sows are costly as they leave the herd earlier, are less productive, and are more likely to die or be euthanized versus culled. Housing methods play a role in the odds of removal for lameness and should be further investigated.
... However, many sows are replaced before they can yield ideal reproductive efficiency, which causes a significant economic loss [6]. To reach breakeven for a sow, it needs to produce at least three litters before being removed [7,8]. In practice, approximately one-third of overall removals in gilts are due to reproductive failure, where conception failure and lack of observed estrus are the major reasons [9]. ...
Accurate estrus detection of sows is critical to achieving a high farrowing rate and maintaining good reproductive performance. The conventional method of estrus detection uses a back pressure test by breeding technicians, which is time-consuming and labor-intensive. This study aimed to develop an automated estrus detection method by monitoring the change in vulva swelling around the estrus using a LiDAR camera. A total of seven multiparous individually housed sows and a gilt were monitored once per day for 19 consecutive days, starting from 2 days before they stopped receiving Matrix®. A three-dimensional (3D) point cloud of the vulva region was manually acquired using the LiDAR camera at 0.7 - 1.0 m from the back of the sows. The accuracy of the LiDAR camera was examined in a laboratory before imaging sows. Results showed that the measurement error in depth was 3.4 ± 3.0 mm (mean ± SD). Collected point cloud data of sows were processed using a customized algorithm to create 3D models of the vulva region by separating them from the sow's body. Five 2D and 3D features were extracted from the 3D models to describe vulva size. Linear regression analysis showed that the calculated volume (CV = width × length × height) could represent the vulva volume (R²=0.92). Results also showed that the vulva volume was a reliable estrous indicator. Swelling duration and intensity showed large variation among different sows. This study also indicates that sows with larger vulva volume had a smaller percentage of increase around estrus. The results suggest that the LiDAR camera has the potential as a non-invasive tool to help identify the sow's estrus.
... Sows lifetime reproductive performance is a key component for farm productive e ciency and pro tability. Sows staying longer in the herd produce more litters and lifetime piglets born alive (Koketsu et al. 2017) contributing to recoup their initial replacement costs and to improve overall farm nancial performance (Gruhot et al. 2017b;Stalder et al. 2003). There are several metrics to evaluate sow lifetime performance including productive life (i.e. ...
This study aimed to 1) investigate associations between first parity wean-to-service interval (WSI) and sows’ lifetime reproductive traits and 2) identify cut-off values for WSI associated with lifetime traits. Data collected in 3,900-sows of farrow-to-finish commercial farm in Yucatan, Mexico. Lifetime productivity records including parity number at culling (NPC), lifetime number piglets born alive (LNBA) from parity two until culling, lifetime non-productive days (LNPD) and length of productive life (LPL) for sows were used. Association between WSI and sow productive traits were evaluated using general linear models, including year and season as categorical fixed effects and WSI as a continuous linear and quadratic predictors. Cut-off values for WSI were estimated using regression tree analysis. WSI was associated ( P < 0.05) with LNBA (linear = -0.62 ± 0.025; quadratic 0.02 ± 0.008) and NCP (linear = -0.04 ± 0.018). Similarly, an association ( P < 0.05) was observed between WSI and LNPD (linear = 2.81 ± 0.687; quadratic -0.05 ± 0.023). Cut-off values for WSI varied according to each of the predicted variables: WSI > 5 days would translate into longer 13 more days of LPL, WSI < 7 days would increase LNBA by two extra pigs, WSI ≥ 9 days increases NCP by 0.2 parities, and WSI < 10 days would mean 24 fewer LNPD. Shorter WSI during the first parity was associated with improved lifetime productivity traits. The estimated cut-off values for WSI could be used by producers, to decide when to implement strategies to improve management.
Reproductive failure is the main reason for culling females in swine herds and is both a financial and sustainability issue. Because reproductive traits are complex and lowly to moderately heritable, genomic selection within populations can achieve substantial genetic gain in reproductive efficiency. A better understanding of the physiological components affecting the expression of these traits will facilitate greater understanding of the genes affecting reproductive traits and is necessary to improve and optimize management strategies to maximize reproductive success of gilts and sows. Large‐scale genotyping with single‐nucleotide polymorphism (SNP) arrays are used for genome‐wide association studies (GWAS) and have facilitated identification of positional candidate genes. Transcriptomic data can be used to weight SNP for GWAS and could lead to previously unidentified candidate genes. Resequencing and fine mapping of candidate genes are necessary to identify putative functional variants and some of these have been incorporated into new genotyping arrays. Sequence imputation and genotype by sequence are newer strategies that could reveal novel functional mutations. In this study, these approaches are discussed. Advantages and limitations are highlighted where additional research is needed.
Factors associated with decreased frequency of micturition appeared to predispose sows to urinary tract infections (UTI) which are characterized by cystitis, ureteritis and pyelonephritis. We aimed to investigate the possible associations between the frequency and severity of claw lesions or the intensity of claw overgrowth with cystitis in culled sows. At slaughter, we collected from 185 culled sows from three Greek farrow-to-finish herds the urinary bladders and feet. The bladders were histopathologically examined. The claws were macroscopically evaluated and scored for lesions in five anatomical claw sites (the sole, the heel, the wall, the white line and the coronary band). Additionally, four claw length measurements (i. the distance from the dorsal skin-horn junction (periople) to the apex of the toe, ii. the distance from the apex of the toe to the skin-horn junction at the heel, iii. the length of the abaxial wall (sole) and bulb (heel) that are in contact with the floor surface, and iv. the length of the dewclaws) were recorded per toe. Cystitis was recorded in 85/185 (45.94%) sows. All sows had at least one lesion on any site, on any foot. The proportion of sows with at least one lesion in each claw site was similar among herds (all P>0.05). Multivariable analyses revealed no association either between cystitis and claw lesions or between cystitis and claw length measurements. This result may have been biased by the fact that our study's population comprised mainly sows which had terminated their productive life (parity range 1-9, median=6 inter-quartile range=4). Inadvertently, this may have reduced variation in claw lesion frequency or severity and of the intensity of claw overgrowth in comparison to the reference population of productive sows.
The present study was part of a larger experiment that evaluated litter of origin effects on gilt production. The objectives of this study were to determine the effect of physical or fenceline boar exposure and exogenous gonadotropins on puberty induction and subsequent fertility in a commercial farm environment. The experiment was performed in three replicates. Prepubertal gilts were assigned by pen (13/pen) to receive 15 min of daily Fenceline (FBE, n = 153) or Physical (PBE, n = 154) Boar Exposure (BE) for 3 weeks starting at 184 d of age in a purpose-designed Boar Exposure Area (BEAR). At the start of week 3, prepubertal gilts were randomly assigned to receive PG600 or none (Control). From weeks 4 to 6, estrus was checked using only FBE. During weeks 1 to 3, measures of reproductive status were obtained weekly or until expression of estrus. Upon detection of first estrus, gilts were relocated into stalls and inseminated at second estrus. PBE reduced age (P = 0.001) and days to puberty (P = 0.002), increased the proportion of gilts in estrus (P = 0.04) in week 1 (38.3 vs. 27.5%), and tended (P = 0.08) to improve estrus in week 2 (37.6 vs. 26.1%) compared to FBE, respectively. In week 3, more prepubertal gilts receiving PBE-PG600 exhibited estrus (P = 0.04; 81.8%) compared to PBE-Control (40.3%), FBE-PG600 (56.4%), and FBE-Control (47.8%). Overall, expression of estrus through week 6 tended (P = 0.08) to be greater for PBE than FBE (91.5 vs. 85.0%). PBE increased (P ≤ 0.05) or tended to increase (P > 0.05 and ≤0.10) service and farrowing rates in parities 1 through 4, but within parity, there were no effects (P > 0.10) on pig production or wean to service interval. Analyses also indicated that weeks from start of boar exposure to puberty, litter of origin traits, and follicle measures at puberty were related to the subsequent fertility. The results of this study confirm the advantages of using increased intensity of boar exposure, combined with PG600 treatment, for effective induction of pubertal estrus in a commercial setting.
Longevity and reproductive performance are economically important traits in the swine industry that are largely influenced by nutrition and other environmental factors. Reproductive performance and longevity through 4 parities was assessed in gilts of 2 genetic lines developed on ad libitum access to feed or restricted to 75% of ad libitum intake. A total of 661 gilts were used in a 2 x 2 factorial with half of the gilts allocated to an ad libitum diet (AL; n = 330), while the other half were energy restricted by 25% (R; n = 331) from 123 to 235 d of age. All gilts were sired by an industry maternal line. Dams of the gilts were from either a Large White by Landrace industry maternal line or Nebraska Selection Line 45X, producing gilts designated as W x L (n = 355) and L45X (n = 306), respectively. Daily estrus detection began at 140 d of age to obtain age at puberty (AP). Gilts (n = 510) were mated on their second or later estrus, beginning at 240 d of age. Sow weight and backfat were recorded at 110 d of gestation and weaning of each parity. Number of live-born, stillborn, and mummified pigs per litter and piglet birth and weaning weights were recorded through 4 parities. More L45X than W x L and more AL than R gilts reached puberty by 230 d of age (P < 0.01). Dietary treatment did not affect probability to produce parities 1 to 4 or any litter trait analyzed. The L45X females tended to be more likely to produce parities 1 (P < 0.08) and 3 (P < 0.06), while W x L had heavier litters at birth (P < 0.01) and weaning (P = 0.01). Treatment by parity interactions (P < 0.01) existed for weight and backfat prior to farrowing and backfat at weaning, and weight at weaning exhibited a line by treatment by parity interaction (P = 0.04) as R sows had lower weights and backfats in earlier parities, but caught up to AL sows in later parities. A treatment by parity interaction (P < 0.01) was also present for backfat loss from farrowing to weaning as R gilts lost less backfat than AL in parities 1 and 2, but more in parities 3 and 4. No significant differences were detected between lines or treatments for lifetime production traits. The populations of pigs and data presented here provide a framework for a diverse array of further studies. Alternative approaches to restrict energy have been assessed in addition to methods of marker-assisted and genomic selection for improvement of litter size and sow longevity.
Background
Cull sows are a unique population on swine farms, often representing poor producing or compromised animals, and even though recent studies have reported that the microbiome is associated with susceptibility to diseases, the microbiome of the cull sow population has not been explored. The main objective of this study was to investigate whether there were differences in fecal and upper respiratory tract microbiota composition for groups of sows of different health status (healthy, cull, and compromised/ clinical sows) and from different farms (1 to 6).
Methods
Six swine farms were visited once. Thirty individual fecal samples and nasal swabs were obtained at each farm and pooled by five across health status and farm. Samples underwent 16S rRNA gene amplicon sequencing and nasal and fecal microbiota were analyzed using QIIME2 v.2021.4.
Results
Overall, the diversity of the nasal microbiota was lower than the fecal microbiota ( p < 0.01). No significant differences were found in fecal or nasal alpha diversity by sow’s health status or by farm. There were significant differences in nasal microbial composition by farm and health status (PERMANOVA, p < 0.05), and in fecal microbiota by farm (PERMANOVA, p < 0.05), but not by health status. Lastly, at the L7 level, there was one differentially abundant taxa across farms for each nasal and fecal pooled samples.
Discussion
This study provided baseline information for nasal and fecal microbiota of sows under field conditions, and results suggest that farm of origin can affect microbial diversity and composition. Furthermore, sow’s health status may have an impact on the nasal microbiota composition.
Data from 2 large Australian piggeries were used to estimate genetic parameters and to examine fixed effects for weaning to conception interval (WCI) and farrowing interval (FI) measured in the first 3 reproductive cycles, and sow stayability from the first to later i parities (STAY1i,). WCI and FI recorded following the first farrowing had low heritabilities (h2 = 0.08-0. l0), but estimates did not significantly differ from zero when these traits were recorded in later parities. Heritability estimates for STAY increased with parity of recording, ranging from 0.05 for STAY12 to 0.06 (STAYl3) and 0.09 (STAYl4). Genetic correlations between WCI12 or PI12 and stayability traits ranged from -0.22 to -0.54. Selecting for short WCI following the first farrowing should have favourable consequences for longevity of sows. Important fixed effects for WCI and FI were lactation length and the number of piglets nursed. Both short (<20 days) and long (>29 days) lactation periods led to an increase in WCI12 relative to the optimum lactation length of 21-23 days. WCI also increased with the number of piglets nursed by 1 day/additional piglet for litters ranging in size from <7 to >10 piglets. STAY was little affected by correcting for the average number of piglets born in previous litters.
This discussion considers work on (1) the effects on piglet production of culling rate, energy intake of the sow, ages at 1st mating and 1st farrowing, and age at weaning, (2) the effects of CR and farrowing rate on the length of the reproductive cycle, and (3) the development of a sow productivity index for use as a guide to culling. (Abstract retrieved from CAB Abstracts by CABI’s permission)
To determine whether lactation length was associated with reproductive performance or longevity of sows.
Cohort study.
Data collected between 1986 and 1992 for sows in 15 breeding herds in Minnesota and Iowa.
Sows were grouped into 4 genetic line categories according to their sources and 6 parity categories (1, 2, 3, 4, 5 or 6, and > or = 7). Multivariate regression analysis of reproductive performance was conducted, using the general linear model procedure Logistic regression was conducted with a dichotomous response variable for sow longevity (ie, removal from or retention in the herds). Odds ratios were obtained from estimated coefficients of the regression.
Herd, genetic line, parity, year, month, and lactation length were significant in statistical models for litter (eg, number of live pigs/litter) and interval (eg, weaning-to-mating interval) traits. Interactions between lactation length and year, lactation length and genetic line, lactation length and parity, and lactation length and genetic line and parity were also significant. Sows removed from herds had a significantly shorter lactation length than did sows of the same parity that were retained in the herds. Sows that had shorter lactation lengths were at higher risk of being removed from the herds than were those that had longer lactation lengths.
Lactation length is associated with reproductive performance and longevity, but genetic line and parity play a role as well. Thus, attention should be paid to genetic lines and parity of sows in the herd when implementing an early weaning production practice.