Sow Longevity 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).

The predicted benefits of genomic selection on pig breeding objectives.

The premise was tested that the additional genetic gain was achieved in the overall breeding objective in a pig breeding program using genomic selection (GS) compared to a conventional breeding program, however, some traits achieved larger gain than other traits. GS scenarios based on different reference population sizes were evaluated. The scenarios were compared using a deterministic simulation model to predict genetic gain in scenarios with and without using genomic information as an additional information source. All scenarios were compared based on selection accuracy and predicted genetic gain per round of selection for objective traits in both sire and dam lines. The results showed that GS scenarios increased overall response in the breeding objectives by 9% to 56% and 3.5% to 27% in the dam and sire lines, respectively. The difference in response resulted from differences in the size of the reference population. Although all traits achieved higher selection accuracy in GS, traits with limited phenotypic information at the time of selection or with low heritability, such as sow longevity, number of piglets born alive, pre- and post-weaning survival, as well as meat and carcass quality traits achieved the largest additional response. This additional response came at the expense of smaller responses for traits that are easy to measure, such as back fat and average daily gain in GS compared to the conventional breeding program. Sow longevity and drip loss percentage did not change in a favourable direction in GS with a reference population of 500 pigs. With a reference population of 1000 pigs or onwards, sow longevity and drip loss percentage began to change in a favourable direction. Despite the smaller responses for average daily gain and back fat thickness in GS, the overall breeding objective achieved additional gain in GS.

13 Impact of precision feeding during gestation on the productive career of sows over three reproductive parities

Abstract The aim of this study was to evaluate the impact of precision feeding during gestation on the career performances and longevity of sows, initially gilts, monitored over three successive reproductive cycles. Four isoenergetic treatments were compared: two conventional constant-concentration feeding strategies (0.53 % DIS Lys) with feed supply either constant (flat feeding; FF) or variable (bump feeding; BF), and two precision feeding strategies based on the InraPorc model applied considering either the mean weight by parity (PFP) or the individual weight of each sow at breeding (PFI). Four groups, representing 393 gilts, were followed from breeding to weaning over three cycles. Body weight and backfat depth were measured at breeding, 90 d of gestation, parturition, and weaning. Feed consumption was monitored daily. Litter variables were measured, including birth and weaning weight, mortality, and overall body weight gain. A mixed model was used to analyze differences between the four treatments using the sow as the experimental unit for performance analysis during the third reproductive cycles. For the analysis of the overall productive career over the three reproductive cycles, the performances of the two conventional strategies (with constant Lys DIS concentration feeding, CONV) were compared with the two precision feeding strategies (PF). During the third cycle, PFP and PFI sows had a lighter body weight at the beginning of gestation than the FF sows (P < 0.01), but increased their body weight gain during gestation (P < 0.001). Backfat loss in PFP and PFI sows during lactation was greater compared with BF sows (P = 0.05), FF sow being intermediate. PFP sows had a lower stillborn rate (P = 0.04) and tended to have less total piglet mortality (P = 0.06) than FF and BF sows. Over the three reproductive cycles, the stillborn rate and total piglet mortality were less in PF sows than in CONV sows (respectively -0.9 %; P = 0.02 and -1.5 %; P = 0.03). PF sows weaned more piglets during their three cycles than CONV sows did (+ 0.7; P = 0.03), with weaning litter weight gain also increasing for PF sows (+3.7 %; P = 0.02). The culling rate of gilts after three cycles did not differ significantly among treatments (P = 0.27), but tended to be greater for PF sows after one cycle (+4.9 %; P = 0.08). The results seem to show a lasting benefit of precision feeding for sows, with a decrease in piglet mortality during lactation, suggesting greater piglet viability without significantly decreasing sow longevity.

Marine-derived Ca-Mg complex influences lipid and glucose metabolism, serum metabolites, colostrum profile, and stress hormone in sows over four-parity periods.

Minerals is required small amounts among various nutrients, but it has a significant impact on sow longevity and reproduction performance. This study was carried out to see the beneficial effects of marine-derived Ca-Mg complex on the reproductive performance of sows during four-parity periods. Seventy-two gilts ([Yorkshire × Landrace] × Duroc), with an average body weight of 181 kg, were randomly allocated to three groups; CON (basal diet), 0.3LC (CON - MgO - 0.3% limestone + 0.4% Ca-Mg complex), and 0.7LC (CON - MgO - 0.7% limestone + 0.4% Ca-Mg complex). During parity 3 and 4, the expression level of SCD gene was lower in the umbilical cord of piglets born to 0.3LC and 0.7LC sows compared with the CON sows. During parity 2, 3 and 4, SLC2A2 and FABP4 gene expressions were higher in the umbilical cord of piglets born to 0.7LC sows and the placenta of sows from 0.3LC groups, respectively. Ca-Mg complex increased (p < 0.05) Ca and Mg concentrations in sows and their piglets' serum as well as in colostrum regardless of parities. The serum vitamin D concentration was higher (p < 0.05) in their first parity, whereas serum prolactin and estrogen concentrations were higher (p < 0.05) during the fourth and third parity, respectively. The growth hormone concentrations were higher (p < 0.05) in the piglets born to sows during the first and second parity. The fat and immunoglobulin A (IgA) concentrations in colostrum were higher (p < 0.05) during the third and fourth parity, respectively. A reduction (p < 0.05) in salivary cortisol, epinephrine, and norepinephrine concentrations was observed in 0.3LC and 0.7LC sow groups compared with CON after farrowing regardless of parity, however before farrowing, a reduction in norepinephrine was observed. Before farrowing, the epinephrine and norepinephrine concentrations were higher (p < 0.05) during the first and second parity. After farrowing, the concentration of these hormones was higher during the second parity. Taken together, sows' parity and dietary Ca-Mg complex supplementation influenced serum metabolites, colostrum nutrients, stress hormones as well as the gene expressions related to lipid and glucose metabolism.

PSIV-18 Live Yeast (Saccharomyces Cerevisiae) Improves Body Condition Score and Reduces Rectal Temperature in Sows at Weaning

Abstract Achieving optimal health of the sow during gestation and lactation is important to ensure sow longevity and piglet performance. As an oxygen scavenger, live yeast suppresses the growth of undesirable bacteria and promotes fiber-degrading microbes. Consequently, yeast has the potential to promote a healthy gut microbiome and support immune status. Therefore, the objective of this study was to evaluate the effects of live yeast supplementation on sow performance during gestation and lactation. A total of 40 sows (Landrace × Yorkshire) were assigned to two dietary treatments based on parity and expected farrowing date. The two dietary treatments consisted of a basal diet without (control) or with supplementation of live yeast (Vistacell, AB Vista, UK). Gestation diets were fed for 4-weeks pre-farrowing with the live yeast treatment included at 0.5 kg/t. Lactation diets were fed from farrow until weaning at approximately 24 days with live yeast treatment included at 1.0 kg/t. Data were analyzed by ANOVA using the standard least squares option of the fit model platform in JMP 16.0 Pro. Treatment differences were deemed significant at P &amp;lt; 0.05. At farrowing, sows had comparable body weights, backfat thickness, muscle depth, rectal temperature (rTEMP) and body condition score (BCS), irrespective of treatment. At weaning, sows supplemented with live yeast had a greater BCS (3.4 vs. 3.0) than non-supplemented sows (P &amp;lt; 0.01). As average daily feed intakes were comparable across treatments, this suggests that live yeast fed sows were better able to retain condition during the lactation period. In addition, rTEMP was lower (38.6°C vs 39.1°C) in sows fed live yeast at the end of lactation compared with non-supplemented sows (P &amp;lt; 0.05). Although rTEMP was considered within the safe range for sows post-farrow, lowering rTEMP with live yeast may indicate health benefits to the sow. These findings demonstrate the potential of live yeast to improve body condition and reduce the risk of vulnerable sows at weaning.

Marine derived Ca-Mg complex supplementation basal diet during four subsequent parities improved longevity and performance of sows and their litters.

The aim of the present study was to evaluate the effects of dietary supplementation of Ca-Mg complex on the longevity and reproductive performance of sows. In total, seventy-two gilts ([Yorkshire × Landrace] × Duroc, average body weight 181 kg) were randomly allocated to 1 of 3 treatments during 4 successive parity in a 4 × 3 factorial arrangement. Treatments consisted of CON (basal diet), CM1 (basal diet -MgO - 0.3% limestone + 0.4% Ca-Mg complex), and CM2 (basal diet - MgO - 0.7% limestone + 0.4% Ca-Mg complex). A higher (p < 0.05) number of totals born and live piglets, and sows increased feed intake during gestation and lactation, increased backfat thickness, and increased estrus interval were observed (p < 0.05) during their third and fourth parity than during their first and second parity. Ca-Mg complex supplementation improved (p < 0.05) the number of total piglets during the first and second parity as well as live-born piglets during the first to third parity, reduction (p < 0.05) in backfat thickness during the third and fourth parity, a higher (p < 0.05) initial and final number of suckling piglets as well as higher weaning weight compared with sows fed CON diet during the first, second, and third parity. The average daily gain (ADG) was higher (p < 0.05) in piglets born to CM1 and CM2 sows regardless of parity. The treatment diets fed to sows lowered (p < 0.05) the duration of first to last piglet birth and placenta expulsion time compared with CON sows. A significant interactive effect (p = 0.042) between parities and treatment diets was observed for the first to last piglet birth. Thus, Ca-Mg complex supplementation by partially replacing limestone in the basal diet enhanced sow performance, specifically during their third and fourth parity, thereby improving sow longevity.

Genetic parameters for linear conformation, stayability, performance and reproduction traits in German local Swabian-Hall landrace sows.

Improvements of longevity in sows are of overriding importance from an animal welfare as well as from an economic perspective, also in the local Swabian-Hall Landrace (SHL) breed. Consequently, the aim of the present study was a detailed assessment of linear conformation traits in the context of early predictions of sow stayability and to infer genetic (co)variance components between conformation traits with reproduction and performance traits. In this regard, we implemented a linear 9-point scoring system for conformation traits reflecting the body morphology and feet and leg characteristics in gilts. Linear conformation trait scoring included body length (BLEN), body height (BHEI), hind leg angularity (HLANG), hind leg pastern (HLPAS), hind cannon bone strength (HCBS), hind leg position (HLPOS), front leg position (FLPOS), claw length (CLEN) and muscling (MUSC) from 6042 SHL gilts before first insemination at the age of 180-200 days. For the same gilts, performance traits included average daily gain (ADG) and back fat thickness (BF) measured via ultrasound, reproduction traits included the number of piglets born alive (NBA) and the number of piglets weaned (NWEAN), and stayability was a binary trait reflecting sow survival after parity 2 (STAY_12), 3 (STAY_13) and 4 (STAY_14). For the estimation of variance components and heritabilities, single-trait linear animal models were defined for conformation, performance and reproduction traits, and single-trait generalized linear mixed models with a logit link function for binary stayability traits. Genetic covariances and correlations were inferred in series of bivariate runs for all combinations of conformation and remaining traits. The distribution of the assigned conformation scores reflected a Gaussian distribution, but a large fraction of records was assigned to the intermediate score classes 4, 5 and 6. Accordingly, the restricted utilization of the 9-point scale might explain the small genetic variances and small heritabilities for feet and leg traits in the range from 0.06 to 0.17. Heritabilities were larger for the linear traits reflecting body morphology, i.e., for BLEN (0.21) and BHEI (0.20). For conformation traits, the common litter environment explained up to 17% of the phenotypic trait variation. Genetic and especially phenotypic correlations between linear conformation traits with the reproduction traits NBA and NWEAN were close to zero. Heritabilities for STAY_12, STAY_13 and STAY_14 were 0.08, 0.07 and 0.05, respectively. Moderate genetic relationships were estimated between STAY_14 with some conformation traits. Especially high scores for BHEI and BLEN (i.e., long and large gilts) implied a decline in STAY_14 genetically (rg =-0.24 and -0.53, respectively). Moderate genetic correlations were estimated between HLANG with STAY_14 (0.28), and between HCBS with STAY_12 (0.23). For most of the conformation traits with intermediate optimum, genetic correlations with STAY were close to zero, indicating improved longevity for gilts representing the population average with scores 4, 5 or 6, and suggesting the development of appropriate selection indices in this regard.

Effect of a multicarbohydrase containing α-galactosidase in sow lactating diets with varying energy density.

Sow productivity improvements are associated with high energetic demand due to increasing prolificity. The reproductive life and longevity of sows, and the readiness for weaning of the offspring may be impaired when sows loose significant body weight (BW) during lactation. The impact of a multicarbohydrase containing α-galactosidase on a low energy dense lactation diet was evaluated in this study. Two-hundred and eight sows (208 ± 25.2 kg) were blocked by parity and BW to one of four treatments, in which a corn-soybean meal diet was formulated to have varying levels of added fat (0, 1.5%, and 3%) to titrate an energy density model. A fourth treatment replicated the 0% added fat formulation with enzyme supplementation at 250 g/tonne. Sows were weighed individually on entry, post-farrow (by calculation) and at weaning. Daily feed intakes (ADFI) and caloric intake were used for calculation of sow feed efficiency (FE) and caloric efficiency. Litter performance was characterized at birth, and size was standardized within 24h of farrow and within treatment to ensure uniform litter sizes. Average wean weight and pre-weaning mortality were determined. Piglets were weighted individually to study litter weight distribution. Data was analyzed as a randomized completely block design, using sow as the experimental unit, treatment as the main effect, and standardized average weight and litter sizes as covariates where appropriate. Although sows fed a multicarbohydrase had lower standardized litter size (P < 0.001), average wean weight was higher in this group and equivalent to the 3% added fat treatment. Enzyme supplementation tended to reduce the proportion of light weight pigs (BW < 4.1kg) within the litter, when compared with the 0% added fat diet (P < 0.1). The multicarbohydrase tended to increased sow ADFI (P < 0.10), although sows from all treatments had equivalent caloric intakes during lactation (P > 0.1). Enzyme supplementation yielded significant improvements in sow FE (P < 0.01), similar to the 3% added fat group. Thus, the carbohydrase degrading enzyme tested in this study improved the efficiency of sows, while increasing average wean weights of the offspring, suggesting an improvement in nutrient digestion and/or metabolic efficiency from typical lactation diets.

PSXVI-8 Marine-Derived Ca-Mg Complex Influences Serum Metabolites, Colostrum Nutrient Profile, Lipid and Glucose Metabolism-Associated Genes Expression, and Stress Hormones in Sows Over a Four-Parity Period

Abstract Among different nutrients, the requirement of minerals is small, but impacts sow longevity and reproduction performance. Cross bred gilts (n=72; average body weight 181 kg) in their 1st to 4th subsequent parity was randomly allocated to 1 of 3 treatments (24 gilts/treatment) to assess the effects of marine derived Ca-Mg complex supplementation on serum mineral contents, hormone concentrations, colostrum nutrient profile, as well as lipid and energy metabolism-associated genes expression in the placental, and umbilical cord tissues. Treatments consisted of CON (corn-soybean meal-wheat-based basal diet with limestone as main Ca source), CM1 (CON-MgO + 0.40% marine derived Ca-Mg complex formulated to have same Ca and Mg spec as basal diet), and CM2 (CON - 0.4% limestone + 0.4% marine derived Ca-Mg complex - MgO). The inclusion of Ca-Mg complex in sow diet increased (P&amp;lt; 0.05) the serum Ca and Mg levels, colostrum Ca, Mg, protein, and IgM contents, and reduced stress hormones after farrowing. However, depletion of Ca and Mg was observed in the 4th parity sows fed CON diet and a reduction in stress hormones were observed in 3rd and 4th parity sows. The relative expression of the SCD gene was downregulated in the umbilical cord of piglets born to CM1 and CM2 sows compared with the CON group during parity 3 (P= 0.007) and parity 4 (P = 0.009). During the parity 4, SLC2A2 (P = 0.003) and FABP4 (P = 0.043) genes expression were upregulated in the umbilical cord of piglets born to CM2 sows and placenta tissue of sows from CM1 group, respectively. The observed positive influence of marine-derived Ca-Mg complex on lipid and glucose metabolism-associated genes expression, serum metabolites, colostrum nutrient, and stress hormones suggests that inclusion of 0.4% Ca-Mg complex in the diet is beneficial for improving sow longevity and performance.

The importance of optimal body condition to maximise reproductive health and perinatal outcomes in pigs.

Overnutrition or undernutrition during all or part of the reproductive cycle predisposes sows to metabolic consequences and poor reproductive health which contributes to a decrease in sow longevity and an increase in perinatal mortality. This represents not only an economic problem for the pig industry but also results in poor animal welfare. To maximise profitability and increase sustainability in pig production, it is pivotal to provide researchers and practitioners with synthesised information about the repercussions of maternal obesity or malnutrition on reproductive health and perinatal outcomes, and to pinpoint currently available nutritional managements to keep sows' body condition in an optimal range. Thus, the present review summarises recent work on the consequences of maternal malnutrition and highlights new findings.

Reasons for Culling in Relation to Longevity and Lifetime Efficiency of Landrace and Large White Sows in a Nucleus Breeding Farm in the Philippines

Information on the reasons for sow removal is limited and often unreported for nucleus breeding farms. This study analyzed the distribution of culling type (planned vs. unplanned) and culling reasons in relation to longevity – parity at culling (PAC) and productive herd life (PHL), and lifetime efficiency – lifetime pigs born alive (LPBA) and total pigs weaned (TPW) using data recorded from 2017 to 2019 by a local nucleus breeding farm. The study revealed a considerable amount of unplanned removal (84.1%) compared to planned culls, which is due to old age (11.4%) and poor farrowing performance (4.6%). The most common reasons for unplanned sow removal were reproductive failures (26.2%) and health disorders (23.4%), followed by physical defects (15.3%), leg/foot problems (10.8%), and mortality (8.5%). A high proportion (22.1%) of sows was culled at their first parity. The proportion of culled sows decreased up to parity 4, especially for unplanned sow removals due to reproductive failures, leg/foot problems, and mortality. Unplanned culling corresponded to lower PAC (3.8), PHL (459 days), LPBA (14.1 pigs/year), and TPW (12.4 pigs/year). Average PAC and PHL were significantly higher (p<0.05) for Large White sows (PAC= 5.2; PHL= 696 days) than Landrace sows (PAC= 4.6; PHL= 588 days). However, the LPBA and TPW were not significantly different between breeds. Information about sow removal could be used to develop management strategies to avoid unplanned culling in purebred sows and extend their productive life.

Gilt rearing impacts on sow performance and longevity – a review

Lifetime performance and longevity are very important parameters of profitability in sow breeding. Opportunity to improve lifetime performance and longevity may be found in the rearing period and preparation of gilts for their future reproductive role. With the aim to prevent premature culling, it is possible to influence body condition, limb condition, mammary gland development, and proper function of the reproductive tract through nutrition, technology, and rearing strategies. Nutrition plays a very important role, as it can affect all the basic requirements for achieving satisfactory gilt performance. Selecting the most effective rearing strategy can be difficult because there are many factors affecting performance and longevity. The aim of this literature review is to provide up-to-date information on how sow longevity and performance can be influenced through choice of gilt rearing strategies and the important area of nutrition.

Effects of restricting energy during the gilt development period on growth and reproduction of lines differing in lean growth rate: responses in reproductive performance and longevity.

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 × 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 (W) by Landrace (L) industry maternal line or Nebraska Selection Line 45X, producing gilts designated as W × 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 × 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 × 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.

Description of on-farm treatment compliance and risk factors for culling in sows

BackgroundIn commercial pig farming, sick or injured sows are often treated by producers or hired staff. To date, limited quantitative data exists on treatment compliance and the possible effect on sow longevity post-treatment. The objective of the study was to quantify on-farm compliance of treatment selection, frequency, and dosage, as well as to investigate the association between body condition scores (BCS) and other sow-level factors on post-treatment cull risk.ResultsOn-farm treatment records, including culling reason or reason of death up to 6 months post-treatment, production records and sow characteristics were obtained for 134 sows over an 8-week period. Treatment compliance was based on the accuracy of recorded treatments compared to the herd veterinarian’s established treatment guidelines. Univariable and multivariable logistic regression models including treatment reason, treatment compliance, BCS, parity, production stage and production metrics, were constructed to investigate associations between those variables and sow culling or death. This study found low compliance for on-farm sow treatment protocols, with only 22.4% (30/134) of the sows receiving correct and complete treatment during the duration of the study. No effect of individual treatment components (drug, dosage, or frequency) on sow culling was observed. A trend for an interaction between treatment compliance and BCS was found, and parity and number of piglets born alive were identified as predictors for sow maintenance in the herd.ConclusionsOn-farm sow treatment compliance was low, resulting in that approximately 80% of the enrolled sows were not treated according to existing guidelines. Non-compliance of treatment guidelines did not seem to affect the risk of culling in treated sows but may have prolonged any associated pain, recovery time and negatively impacted the sow welfare during that time period.

130 Utilization of Nutrack to Assess Variance Components and Heritability of Activity Traits

Abstract Overall activity and behavior are integral components of sows remaining productive in the herd. This investigation studied overall activity of group housed replacement gilts and the heritability of various activity traits. Beginning around 20 wk of age, video recorded data of approximately 75 gilts/group for a total of 2,378 gilts over 32 groups was collected for 7 consecutive d using the NUtrack System, which tracks distance travelled (m), avg speed (m/s), angle rotated (degrees), and time standing (s), sitting (s), eating (s), and laying (s). The recorded phenotypes were standardized to the distribution observed within a pen for each group. The final values used for analysis were the average daily standardized values. Data were analyzed using mixed models (RStudio V 1.2.5033) including effects of sire, dam, dam’s sire and dam, dam’s grandsire and granddam, farrowing group, barn, pen, and on-test date. Sire had an effect on every activity trait P &amp;lt; 0.001), and dam had an effect on average speed (P &amp;lt; 0.001). The dam’s sire had an effect on all activity traits (P &amp;lt; 0.001) and the dam’s grandsire had an effect on average speed (P &amp;lt; 0.001). Heritabilities and variance components of activity traits were estimated in ASReml 4 using an animal model with a two-generation pedigree. Genetic variances are 0.17 +/- 0.029, 0.19 +/- 0.034, and 0.11 +/- 0.024, residual variances are 0.37 +/- 0.023, 0.41 +/- 0.027, and 0.41 +/- 0.022, phenotypic variances are 0.54 +/- 0.018, 0.60 +/- 0.020, and 0.52 +/- 0.016, and heritabilities are 0.32 +/- 0.048, 0.32 +/- 0.049, and 0.21 +/- 0.044 for average speed, distance, and lie respectively. NUtrack offers potential to aid in selection decisions. Given the results presented herein, continued investigation into these activity traits and their association with sow longevity is warranted.

11 Metal Amino Acid Chelates/complexes with Emphasis on Molecule Absorption and Efficacy Differences in Swine

Abstract The objective of this presentation will be to discuss differences in the molecular structures between various organic trace minerals (OTM) and inorganic trace minerals (ITM) and discuss how these properties impact stability, absorption, bioavailability and retention. The Association of American Feed Control Officials (AAFCO) lists several different categories of OTM including chelates, complexes and proteinates. Typical ligands include organic acids, amino acids, peptides and polysaccharides. It is widely known that bioavailability of ITM is low, primarily due to the presence of antagonisms such as phytate and/or fiber or excesses of other minerals. For this reason, inclusions of trace minerals (e.g. Zn, Cu, Mn, Fe) are often added in commercial livestock diets at 2–3-fold higher concentrations than recommended by NRC. Feeding highly bioavailable trace minerals is important. These minerals are required components of thousands of the proteins, enzymes and transcription factors that support a wide variety of biochemical processes in the cells and tissues of animals. These functions include gene regulation, cell growth and division, immune development and function, tissue development and integrity, reproduction and oxidative stress management. Low bioavailability of these trace minerals can reduce animal performance, immune function, reproductive performance and increase lameness. Numerous in vitro and in vivo methodologies have been used to compare bioavailability and demonstrate higher stability, tissue retention and digestibility of OTM vs ITM. Sow longevity is a key factor in commercial swine herd profitability. Reproductive problems and lameness are the most common reasons for premature sow culling from breeding herds. Compared to ITM, OTM reduced gilt and sow mortality 9–17% (P &amp;lt; 0.10), culling rate 20–35% (P &amp;lt; 0.01) and increased sow retention (through parity 3) 5–10%; (P &amp;lt; 0.01). Greater bioavailability translates to biological benefits to the producer, however, our findings demonstrate that not all OTM perform better than ITM.

Potential functional variants in AHR signaling pathways are associated with age at puberty in swine.

Puberty in female pigs is defined as age at first estrus and gilts that have an earlier age at puberty are more likely to have greater lifetime productivity. Because age at puberty is predictive for sow longevity and lifetime productivity, but not routinely measured in commercial herds, it would be beneficial to use genomic or marker-assisted selection to improve these traits. A GWAS at the US Meat Animal Research Center (USMARC) identified several loci associated with age at puberty in pigs. Candidate genes in these regions were scanned for potential functional variants using sequence information from the USMARC swine population founder animals and public databases. In total, 135 variants (SNP and insertion/deletions) in 39 genes were genotyped in 1284 phenotyped animals from a validation population sired by Landrace and Yorkshire industry semen using the Agena MassArray system. Twelve variants in eight genes were associated with age at puberty (P<0.005) with estimated additive SNP effects ranging from 1.6 to 5.3days. Nine of these variants were non-synonymous coding changes in AHR, CYP1A2, OR2M4, SDCCAG8, TBC1D1 and ZNF608, two variants were deletions of one and four codons in aryl hydrocarbon receptor, AHR, and the most significant SNP was near an acceptor splice site in the acetyl-CoA carboxylase alpha, ACACA. Several of the loci identified have a physiological and a genetic role in sexual maturation in humans and other animals and are involved in AHR-mediated pathways. Further functional validation of these variants could identify causative mutations that influence age at puberty in gilts and possibly sow lifetime productivity.

Concordance rate in cattle and sheep between genotypes differing in Illumina GenCall quality score.

Proper quality control of data prior to downstream analyses is fundamental to ensure integrity of results; quality control of genomic data is no exception. While many metrics of quality control of genomic data exist, the objective of the present study was to quantify the genotype and allele concordance rate between called single nucleotide polymorphism (SNP) genotypes differing in GenCall (GC) score; the GC score is a confidence measure assigned to each Illumina genotype call. This objective was achieved using Illumina beadchip genotype data from 771 cattle (12428767 genotypes in total post-editing) and 80 sheep (1557360 SNPs genotypes in total post-editing) each genotyped in duplicate. The called genotype with the lowest associated GC score was compared to the genotype called for the same SNP in the same duplicated animal sample but with a GC score of >0.90 (assumed to represent the true genotype). The mean genotype concordance rate for a GC score of <0.300, 0.300-0.549, and ≥0.550 in the cattle (sheep in parenthesis) was 0.9467 (0.9864), 0.9707 (0.9953), and 0.9994 (0.99997) respectively; the respective allele concordance rate was 0.9730 (0.9930), 0.9849 (0.9976), and 0.9997 (0.99998). Hence, concordance eroded as the GC score of the called genotype reduced, albeit the impact was not dramatic and was not very noticeable until a GC score of <0.55. Moreover, the impact was greater and more consistent in the cattle population than in the sheep population. Furthermore, an impact of GC score on genotype concordance rate existed even for the same SNP GenTrain value; the GenTrain value is a statistical score that depicts the shape of the genotype clusters and the relative distance between the called genotype clusters.

296 Awardee Talk: The Genetics of Sow Longevity

Abstract Sow longevity is a key productivity indicator trait that has real economic and welfare importance for commercial swine farms globally. The average parity at culling is 3.8 parities. Reports indicate that it takes 3 to 4 parities before a sow “pays for herself.” Research groups around the world have reported heritabilities estimates for sow longevity traits ranging from 0.05 to 0.35. Estimate differences result from the animal population under evaluation, the trait being evaluated, and the methodology employed to obtain the genetic parameter estimate. Because sow longevity is measured at the end of the sow’s productive life, indicator traits like age at first farrowing, leg conformation, and other traits are utilized in gilt selection programs. The genetic correlations between sow longevity and lifetime production traits range have been reported to range from 0.64 to 0.94, suggesting that selection will improve sow longevity. Genetic markers have been identified that affect both sow longevity and other indicator traits. Selection to improved sow longevity still requires phenotypes. Future technologies, e.g. CT scans, digital images, and automated disease detection, will provide additional phenotypes. Continued hardware, software, and molecular developments will improve selection accuracy for sow longevity traits and related traits. Research is needed to evaluate the impact that non-additive genetic effects have on sow longevity and other fitness-related traits. Sow longevity seems to be an ideal trait to employ genomic selection in order to make more rapid trait improvements because it is measured late in life, it is sex-limited, and the trait is not directly measured on nucleus animals. In conclusion, sow longevity and related traits have sufficient heritability and variation to improve through traditional and genomic enhanced selection methods. Selection programs employing effective genomic selection programs will be more effective in improving sow longevity trait and related traits and ultimately economical return.

PSVIII-22 Utilization of NUtrack to assess sire influence on pig activity and activity effects on weight

Abstract Structural conformation and behavior are integral components in sows remaining productive in the herd. This initial investigation studied the impact of activity data on weight and the impact of sires on overall activity of group housed replacement gilts. Beginning at 19 wk of age, video recorded data of approximately 75 gilts/wk for a total of 230 gilts over 3 wk was collected for 7 consecutive d using the NUtrack system, which tracks distance travelled (m), time standing (s), eating (s), and laying (s), and angle rotated (degrees). Any d that logged for less than 24 hr were dropped from analysis. Data were analyzed using mixed models (SAS V 9.4) including random effects of dam, barn, pen, and on-test date, and fixed effects including total laying time, angle rotated, distance travelled, time standing, and sire. For 20 wk wt, the mixed model included distance, laying, angle, and standing. Sire had an effect on distance traveled (P &amp;lt; 0.05). The following traits also had an effect on distance: angle (P &amp;lt; 0.01), laying (P &amp;lt; 0.001), standing (P &amp;lt; 0.001), sitting (P &amp;lt; 0.01), and eating (P &amp;lt; 0.01). Pearson correlation coefficient showed a positive correlation between wt and laying (0.26), and negative correlations between wt and distance (-0.34), standing (-0.28) and angle (-0.42). The regression of distance on 20 wk wt yielded a regression coefficient of -0.027 (P &amp;lt; 0.05) m/d per lb and the model explained 11.85% of the variation in 20 wk wt. NUtrack can be utilized to track activities and distance travelled of swine in group pens. Given the results presented herein, continued investigation into the heritability of these activity traits and their association with sow longevity is warranted.