Sow Body Condition Research Articles

Body condition score accuracy and repeatability from evaluation of cull sow digital images at a midwestern harvest facility

The objective of this study was to assess accuracy, repeatability, and reproducibility when evaluating cull sow body condition score (BCS) using a digital medium. Selected digital images were sourced from recorded images of sows brought to a Midwest abattoir. Digital images were collected on 2 separate occasions. Each sample, grouped by capture date, represented a unique scoring session. Scorers (n = 6) with experience at assessing sow body condition used images to assign a BCS to each sow using a 7-point BCS scale. Using applied values, scores were adjusted to the standard 5-point scale. Because scorers assessed individual sows’ body condition from recorded video images, the mode score (BCSMode) was calculated for each sow and considered the gold standard. Scoring distributions, mode scores, individual bias, percent agreement with BCSMode, percent interobserver agreement, Spearman correlations evaluating scorer agreement, repeatability, and reproducibility were calculated. Scorer bias from the pooled cull sow groups (n = 386 total available video images from 2 separate collections) ranged from −0.25 (±0.5) to 0.51 (±0.9). Spearman correlation coefficients for cull sow BCS measured on all sows for all scores during the second scoring round were lower than those observed in the first round. Additionally, it was observed that repeatability estimates improved from round 1 and round 2 (Rd 1 = 0.74 and Rd 2 = 0.76), and reproducibility slightly decreased between round 1 and round 2 (Rd 1 = 0.52 and Rd 2 = 0.47). These repeatability and reproducibility changes demonstrate that as experience level increases, scorers begin to develop their interpretation of the scale used to assess body condition. In turn, they become more repeatable within themselves but may differ from other scorers. The ability for scorers to accurately identify low-BCS sows could serve as a cumulative lifetime welfare indicator where harvest facilities could provide valuable BCS feedback on individual sow and group average basis. The accuracy, repeatability, and reproducibility reported in this study suggest that digital images are an effective medium to assess cull sow BCS.

19 Technology to Efficiently and Effectively Evaluate Body Condition

Abstract Multiple tools are currently available to effectively evaluate gilt and sow body condition. Both A-mode and B-mode ultrasound technology can provide accurate measures of backfat while B-mode ultrasound can deliver precise measures of loin eye area or loin depth. More recently, Knauer invented and developed the sow body condition caliper. The sow caliper technology has been implemented in 39 countries across the world. Quantifying the angularity from the spinous process to the transverse process of a sow’s back, the sow body condition caliper has moderate correlations with weight, backfat and muscling. Recommendations for the “ideal” sow caliper score in relation to reproductive performance come from multiple, large scale studies conducted on commercial farms across an array of modern genetic lines. Results suggest a sow caliper angle of 127.5 to 132.5° maximizes subsequent reproduction. Going forward, tools should be developed to automate the estimation of sow body condition. While the sow caliper provides a low-cost phenotype, automating A-mode and B-mode ultrasound also warrant investigation. Perhaps scientists should collaborate with industry experts to speed the development of automated sow body condition tools.

Dam parity structure and body condition during lactation influence piglet growth and gilt sexual maturation through pre-finishing.

Energy demands during lactation greatly influence sow body condition and piglet performance. We hypothesized that primiparous sows or sows with reduced body condition would produce piglets with reduced growth and delayed sexual maturation. Eight weekly farrowing seasons were used to evaluate sow body condition (post-farrowing, PF and weaning, WN) and piglet growth from 157 dams. Body condition was measured at PF and WN using sow calipers (last rib and hip) and 10th rib ultrasound. Sows were categorized as thin, moderate, or fat by caliper (PF or WN). Individual pig weights were recorded on approximately 1, 10, WN, 45, 100, and 145 d of age. At 100 and 145 d of age, 10th-rib backfat and loin eye area were measured on 567 pigs and first estrus was monitored in 176 gilts reserved for breeding selection beginning at approximately 170 d of age. Sows had similar (P > 0.10) PF last rib caliper measurements but at WN, first parity sows had the smallest caliper measurements compared to other parities (P < 0.05). Parities 1, 2, and 3 sows had similar (P > 0.10) loin eye area at PF; however, at WN first parity sows had the smallest loin eye area (P < 0.05; 38.2±0.63cm2). Parity 1 sows had the greatest (P < 0.05) reduction of backfat and loin eye area over the lactation period (-2.9±0.31mm and -2.6±0.49cm2, respectively). At 1 d of age and WN, piglets from first parity sows weighed the least (P < 0.05) but were the heaviest (P < 0.05) at 100 and 145 d of age. Pigs from first parity litters had larger (P < 0.05) loin eye area at 100 and 145 d of age and greater backfat (P < 0.05) at 145 d of age. Fat sows at WN (last rib or hip) had the lightest (P < 0.05) piglets at 10 d of age and WN. However, at 45 d of age, piglets from fat sows (last rib or hip) were heavier (P < 0.05) than piglets from moderate and thin sows. Tenth rib backfat at 100 and 145 d of age tended (P < 0.10) to be less in pigs reared by thin sows (PF and WN hip). Tenth rib loin eye area was similar among pigs reared by fat, moderate, or thin sows. Gilts developed in litters from fourth parity sows had (P < 0.05) delayed age at puberty in contrast to gilts from first or third parity sows (200.9±4.96 d vs. 189.0±2.29 d and 187.5±2.84 d, respectively). Although progeny body weights were typically less from first parity dams through 45 d of age, these progeny were similar or heavier at 100 and 145 d of age in contrast to progeny from other parities. Furthermore, gilt progeny from first parity dams did not have delayed pubertal attainment.

Dietary Supplementation With Fine-Grinding Wheat Bran Improves Lipid Metabolism and Inflammatory Response via Modulating the Gut Microbiota Structure in Pregnant Sow.

This study investigated the effects of fine-grinding wheat bran on pregnant sow body condition, lipid metabolism, inflammatory response, and gut microbiota. In this study, wheat bran was crushed into three particle sizes. A total of 60 Landrace × Yorkshire second parity sows were allotted to two groups: CWB (a diet containing coarse wheat bran with particle size of 605 μm) and FWB (a diet containing fine wheat bran with particle size of 438 μm). Fine-grinding wheat bran had higher soluble dietary fiber concentration, swelling capacity, water-holding capacity, and fermentability than coarse wheat bran. Pregnant sows fed FWB throughout pregnancy had lower body weight and fat deposition than sows fed CWB. And the piglet body weight at birth of the FWB group was remarkably increased. Serum concentrations of lipids (triglycerides, total cholesterol, and free fatty acid), interleukin 6, leptin, and resistin were decreased on day 90 of pregnancy by fine wheat bran supplementation. Feeding FWB significantly decreased abundance of Firmicutes and dramatically increased the abundance of Bacteroidetes at phylum level. At genus level, the abundance of Terrisporobacter was decreased in FWB feeding sows, but the abundance of Parabacteroides was increased. Fecal total short-chain fatty acids, propionate, and butyrate contents were markedly increased in the FWB group. The results suggested that the physicochemical properties of finely ground wheat bran had been improved. Dietary supplementation with fine wheat bran changed the gut microbiota structure and enhanced the short-chain fatty acids level, which improved the maternal body condition, metabolic and inflammatory status, and reproductive performance in sows.

Protein Digestion Kinetics Influence Maternal Protein Loss, Litter Growth, and Nitrogen Utilization in Lactating Sows

Body protein losses in lactating sows have a negative impact on sow and litter performance. Improving dietary amino acid utilization may limit protein mobilization. The effects of dietary protein kinetics on sow body condition loss, blood plasma metabolites, and plasma insulin-like growth factor-1 (IGF-1), and also on litter gain during lactation, were investigated in this study. In total, 57 multiparous sows were fed one of three lactation diets with the same crude protein level: low level of slow protein diet (LSP) (8% slowly degradable protein of total protein), medium level of slow protein diet (MSP) (12% slowly degradable protein of total protein), or high level of slow protein diet (HSP) (16% slowly degradable protein of total protein) in a complete block design. Our results showed that HSP sows lost the least body weight compared to MSP and LSP sows (11.9 vs. 17.3 and 13.5 kg, respectively; p = 0.01), less body protein than MSP sows (1.0 vs. 2.1 kg; p = 0.01), and tended to lose less loin muscle thickness than LSP sows (1.7 vs. 4.9 mm; p = 0.09) between Day 2 to Day 21 post-farrowing. LSP sows had greatest plasma urea level on Day 6 than MSP and HSP sows (4.9 vs. 3.6 and 3.1 mmol/L, respectively; p < 0.01) and on Day 13 (5.6 vs. 4.1 and 3.7 mmol/L, respectively; p < 0.01). HSP sows had the lowest plasma urea level at Day 20 compared to LSP and MSP sows (4.0 vs. 5.5 and 4.9 mmol/L, respectively; p < 0.01). The average plasma urea level of Days 6, 13, and 20 post-farrowing was negatively correlated with slow protein intake (r = −0.49, p < 0.01). Litter gain, milk composition, and nitrogen output to the environment did not differ significantly among the treatment groups. Therefore, the dietary protein kinetics affected mobilization of maternal reserves in multiparous sows during lactation, with a high fraction of slow protein-sparing protein mobilization.

Evaluation of an on-farm method to assess colostrum IgG content in hyperprolific sows

The colostrum quality (immunoglobulin content) is one of the most challenging aspects for hyperprolific sows in the modern pig industry. The objective of this study was to evaluate relationships among sow body condition scores, litter characteristics, and colostrum IgG content in hyperprolific sows, using a digital Brix refractometer to measure IgG. Samples (5 ml) were collected from two hundred and eighty-seven sows within the first hour postpartum. Sow parameters and back fat thickness at farrowing (BFF) and weaning (BFW) were recorded. The results indicate a positive correlation between parity and IgG, as well as BFF and BFW. A negative correlation was found between the number of weaning piglets and BFW. Moreover, a positive correlation was observed between the number of mummified piglets and colostrum IgG. Finally, lactation duration was positively associated with BFF. In conclusion, the number of mummified piglets is a factor positively associated with colostrum IgG content in hyperprolific sows.

509 Late-Breaking: Effect of a Sensory Additive on Sow Reproductive Performance

Abstract The addition of a sensory additive to sow diets during the summer improved feed intake during lactation, and litter performance. The aim of this study was to evaluate the impact of the sensory additive on sow lactation performance during cooler temperatures. Three consecutive groups (n = 61 total) of sows were farrowed during winter (October, December and January). Sows were weighed, and back fat depth was measured, at 110 d of gestation prior to entering the lactation room, and again at weaning. The sows were sorted by parity, and then allotted by BW at d 110 to Control or 0.075% sensory additive (Luctamax® SowVive, Lucta S.A., Spain). Experimental diets were offered upon entry to the lactation room and fed through weaning. Feed disappearance was recorded every three days. Sows were fed 2.72 kg/head/day until farrowing, and then allowed to eat ad libitum from 24 hours post-farrowing until weaning. Data were analyzed using the PROC MIXED procedure of SAS as an RCBD with treatment as the fixed effect and group as a random effect. No differences were observed on sows feed intake (P &amp;gt; 0.4), 10th rib backfat thickness change (P = 0.632) and body weight change from d 110 of gestation to weaning (P = 0.65, Table 1). Sows fed the sensory additive lowered preweaning mortality by 4.9% (P = 0.051), and weaned an additional 1.42 piglets (P = 0.026) with similar weaning weights (P = 0.86) when compared to control. In conclusion, in the current study, lactation diets supplemented with a sensory additive improved litter performance and helped maintain sow body condition.

Influence of seasonal variation on post-farrowing dysgalactia syndrome (PFDS) and serum biochemistry profiles in the periparturient sow.

The objective of this study was to investigate the effect of seasonal variation on the frequency of post-farrowing dysgalactia syndrome (PFDS), sow body condition score (BCS), piglet survival, and weaning to estrus interval under intensive management systems. In addition, the effects of PFDS on litter characteristics and serum biochemistry, oxidative stress indices, thyroid, and cortisol profile were examined in order to identify potential biomarkers in the pre-farrowing stage. The study was conducted in summer and winter seasons in Nagaland, India, on 50 sows from 30days before farrowing until weaning at 45days. Sows were classified retrospectively into PFDS and non-PFDS. Although statistically, no significant difference was noted in the occurrence of PFDS between the seasons, the proportion of PFDS development was substantially higher in winter than summer (37.5 vs. 26.9%). In winter, the incidence of piglet stillbirth and sow weaning to estrus period was significantly higher (p < 0.05) and the mean litter size at weaning was significantly lower (p < 0.01). At weaning, the mean litter weight and average daily weight gain were decreased (p < 0.05) in both summer and winter, and the total number of piglets died in each litter was increased in sows afflicted with PFDS compared with healthy sows. A significant interaction effect of peripartum days and PFDS was observed in the changes of blood glucose, albumin (p < 0.05), and HDL-cholesterol (p = 0.07) concentration. Mean T3 and T4 concentration was influenced by peripartum days in both the season and a consistently lower T3 concentration was detected in PFDS sows before farrowing. It is concluded that PFDS sows exhibited an increased incidence of stillbirth and scouring of neonatal piglets during the winter. A pronounced drop in mean circulating T3 concentration in sows from 30days before farrowing to 3days after farrowing reflects endocrine-mediated metabolic dysfunction. Further research is warranted with more number of sows to identify the critical values of serum T3 concentration in the immediate pre-farrowing period for prediction of sows developing PFDS after farrowing.

Effect of starting time of co-mingling non-littermates during lactation on performance and skin lesions of sows and piglets

The natural weaning process of piglets is a gradual event, whereas in current commercial pig production weaning is a sudden, stressful phase in the pigs’ life. Management strategies such as co-mingling of non-littermates before weaning aim to mimic (semi)natural conditions and to stimulate social skills in piglets in order to minimize the adverse effects of stress around weaning. The present study investigated in which way timing of co-mingling non-littermate piglets during lactation in conventional farrowing units had implications for the sow and affected the performance and behaviour of piglets before and after weaning. In the experimental treatments, 3 litters were co-mingled either at day 16 before weaning (n = 27 sows and their litters), day 11 before weaning (n = 27) or day 6 before weaning (n = 27). In the control treatment, piglets were not grouped before weaning (n = 27). In total, 1294 piglets were weaned at 21 days of age. At weaning, piglets from 3 litters within each treatment were mixed. Piglets from the co-mingling system were housed with those they were co-mingled with during lactation, whereas control piglets were mixed with unfamiliar piglets. Co-mingling of non-littermate piglets did not affect sow body condition and lesion scores of udder and teats during lactation. Piglets co-mingled 6 days before weaning tended to gain less weight during d-6 – d-1 before weaning (P = 0.082), but piglet growth was not affected during d-16 – d-1. After weaning, the feed to gain ratio in piglets which were co-mingled 6 days before weaning tended to be lowest during the first week after weaning (P = 0.086), but no other treatment effects were observed in the post-weaning phase. Skin lesion score of the shoulders and flanks tended to be higher at day 11 before weaning in piglets co-mingled 16 days before weaning (P = 0.051) and was highest at day 6 before weaning in piglets co-mingled 11 days before weaning (P < 0.001). However, 1 day before weaning no differences in skin lesions were observed. After weaning, the socialized piglets had less skin lesions at the shoulders and flanks compared to control piglets (P < 0.001). In conclusion, pre-weaning co-mingling of non-littermates resulted in less aggression (i.e. lesions) at weaning, suggesting better social skills and a reduction of stress, consistent with a tendency for improved feed to gain ratio in the first week after weaning. Time of co-mingling seemed not crucial.

PSII-19 Effect of a Sensory Additive on Sow Feed Intake During Lactation

Abstract Sow feed intake during lactation is crucial to the maintenance of sow body condition, milk production, and litter performance. Loss of body weight or condition during this time could compromise future reproductive performance. Two groups (n = 52 total) of breeding age gilts and sows were used to evaluate whether a sensory additive would improve intake during the lactation period. Gilts/Sows were weighed, and back fat depth was measured, at 110 d of gestation prior to entering the lactation room, and again at weaning. The sows were sorted by parity and then allotted by BW at d 110 to Control or 0.075% sensory additive (Luctamax® SowVive, Lucta S.A., Barcelona, Spain). Experimental lactation diets were offered upon entry to the lactation room and fed through weaning. During this time feed was weighed back every three days. Gilts/sows were fed 2.72 kg/head/day until farrowing, and sows were placed on full feed 24 hours post-farrowing and allowed to eat ad libitum. Data was analyzed using the PROC MIXED of SAS as an RCBD with treatment as the fixed effect and group as a random effect. During lactation sows on the sensory additive diet showed an increase in intake during days 10 to 21 when compared to sows on the control diet (Table 1). Although it was not significantly different, sows fed sensory additive had numerically heavier weaning BW (239.4 vs 236.2 kg, P = 0.42) and increased litter weight gain (51.96 vs 48.69 kg, P = 0.24) compared to control fed sows. However, backfat thickness change during lactation did not differ between control and sensory additive fed sows (-4.74 vs -5.81 mm, P = 0.65). In conclusion, in the current study lactation diets supplemented with a sensory additive stimulated sow appetite during the lactation period.

Use of bioelectrical impedance spectroscopy to provide a measure of body composition in sows

The ability to accurately estimate fat mass and fat-free mass (FFM) has the potential to improve the way in which sow body condition can be managed in a breeding herd. Bioelectrical impedance spectroscopy (BIS) has been evaluated as a practical technique for assessment of body composition in several livestock species, but similar work is lacking in sows. Bioelectrical impedance uses population-specific algorithms that require values for the apparent resistivities of body fluids and body proportion factors. This study comprised three major aims: (i) to derive apparent resistivity coefficients for extracellular water (ECW) and intracellular water (ICW) required for validation of BIS predictions of total body water (TBW) in live sows against standard reference tracer dilution methods; (ii) to develop predictions of TBW to body composition prediction algorithms, namely FFM, by developing a body geometry correction factor (Kb) and (iii) to compare the BIS predictions of FFM against existing impedance predictors and published prediction equations for use in sows, based on physical measurements of back-fat depth and BW (P2-based predictors). Whole body impedance measurements and the determination of TBW by deuterium dilution and ECW by bromide dilution were performed on 40 Large White x Landrace sows. Mean apparent resistivity coefficients of body fluids were 431.1 Ω.cm for ECW and 1827.8 Ω.cm for ICW. Using these coefficients, TBW and ECW were over-estimated by 6.5 and 3.3%, respectively, compared to measured reference values, although these differences were not statistically different (P > 0.05). Mean Kb was 1.09 ± 0.14. Fat-free mass predictions were 194.9 kg, which equates to 60.9% of total sow weight, and 183.0 kg for BIS and the deuterium dilution method, respectively. Mean differences between the predicted and measured FFM values ranged from −8.2 to 32.7%, but were not statistically different (P > 0.05). Method validation (leave-one-out procedure) revealed that mean differences between predicted and measured values were not statistically significant (P > 0.05). Of the impedance-based predictors, equivalence testing revealed that BIS displayed the lowest test bias of 11.9 kg (8.2%), although the P2-based prediction equations exhibited the lowest bias and percentage equivalence, with narrow limits of agreement. Results indicate although differences between mean predicted and measured values were not significantly different, relatively wide limits of agreement suggest BIS as an impractical option for assessing body composition in individual sows compared to the use of existing prediction equations based on BW and back fat.

PSVII-11 Utilizing digital images to evaluate accuracy and repeatability of body condition score in cull sows

Abstract The objective of this study evaluated the accuracy and repeatability when determining cull sow body condition scores (BCS) evaluated by scorers utilizing digital images. Participants (n=6) were selected based on previous BCS scoring on live sows. Group standards were established utilizing the scores from two participants with extensive experience BCS sows. Other scorers were not provided training before they scored images and no “scorer calibration” activity occurred to ensure that each scorer was observing similar traits when applying BCS. Two separate groups of sows were scored and video images for each sow were collected and stored for evaluation. The images were recorded as a convenience sample from a cooperating sow abattoir. The cull sow video images were assigned a BCS using an 8-point scale (1,1+,2-,2,3,4,5,NS). Scores from the lower portion of the scale were classified (+ and -) to provide a more specific BCS difference evaluation among sows that were thin. When scorers evaluated the sows (n=165) from the first group, they scored the BC for each sow. Additionally, a random group of sows (n=40) images were selected to be scored a second time by the same scorer. Repeatability (inter- and intra- scorer), individual bias, group bias, and group deviation from standard’s mean BCS were calculated. Data from the first sow group showed that relative to the standard’s mean scores, participants overestimated BCS by .41 (P=0.0001). A similarly selected second set of cull sow images obtained from the same abattoir was recorded. The second group included more sow images (n=220) and a greater number images that were scored a second time(n=55) in order to calculate the repeatability values. The same measures described for group 1 were calculated. After data analysis from the second sow group, it was again noted that participants overestimated BCS by 0.1 (P=0.0009).

151 Effect of enhanced organic acid supplementation in late gestation and lactation of sows on body weight change, litter performance and wean to estrus interval

Abstract This study was conducted to evaluate the effects of an enhanced organic acid formulation (EOA; Biotronic PX Top3; BIOMIN America Inc., Overland Park, KS) on sow farrowing and lactation performance, sow weight and backfat change, and wean to estrus interval. A total of 18 crossbred (Yorkshire x Chester White) sows were randomly allocated to one of two dietary treatments which consisted of control (CNT) and EOA supplemented (n = 9 per treatment). Treatment diets were fed to sows from d 90 of gestation until weaning. Sow body weight gain from d 90 of gestation through weaning was greater in EOA supplemented sows compared than CNT sows (30.9 vs 18.1 ± 2.3 kg, respectively; P = 0.010). Backfat from d 90 of gestation through weaning tended to be affected by dietary treatment (P = 0.051), where EOA supplemented sows had an increase in backfat compared to CNT sows which had a decrease in backfat (0.091 vs. -0.046 ± 0.037 cm, respectively). Total number of pigs born was greater for EOA sows compared to CNT sows (13.1 vs. 8.7 ± 1.1 piglets, respectively; P = 0.047). However, number of liveborn, stillborn, and mummified piglets did not differ among dietary treatments (P ≥ 0.207). Additionally, litter growth rate did not differ among dietary treatments (P = 0.631). Wean to estrus interval was longer for EOA sows compared to CNT sows (5.4 vs. 4.7 ± 0.1 days, respectively; P = 0.008). The present results indicate that addition of this EOA to sow diets in gestation and lactation may be beneficial to maintaining sow body condition.

279 Evaluation of the NRC (2012) model in estimating standard maintenance metabolizable energy requirement of PIC sows during mid-gestation

Abstract The objective was to evaluate the NRC (2012) model in predicting standard maintenance metabolizable energy (MEm) of PIC sows during mid-gestation. A total of 201 PIC Camborough sows (parity 1 to 10) were randomly assigned to 1 of 4 treatments in a complete randomized design between day 36 and 46 post-breeding. Treatments consisted of feeding sows with daily feed allowances to meet 80, 90, 100 or 110% of MEm calculated as MEm, kcal/day = 100 × (body weight)0.75. A common corn-soybean meal-based diet with 3,302 kcal of ME/kg and 0.61% standardized ileal digestible lysine was fed for 28 days. Sow body weight (BW) and sow body condition caliper score (CS) were captured at day 0, 14 and 28. Data were analyzed with PROC GLM of SAS with sow as experimental unit. Average sow parity and feed allowance were 4.2 and 1.79 kg/day, respectively. Average sow BW and sow CS at day 0, 14 and 28 were 234, 233 and 242 kg and 14.9, 14.9 and 14.8, respectively. Increasing feed allowances to meet 80 to 110% of MEm requirement increased (linear, P&amp;lt; 0.01) average daily gain (ADG; 0.100, 0.259, 0.417 and 0.440 kg/d, respectively). The estimated regression equation was ADG, kg/day = -0.83 + 1.193 × MEm, estimating the MEm to maintain BW was below 80% of NRC (2012) estimate. Caliper score change (CSC) increased (linear, P&amp;lt; 0.01) with increasing feed allowances to meet 80 to 110% of MEm requirement (-0.78, -0.26, 0.13, and 0.35, respectively). The estimated regression equation was CSC = -3.73 + 3.78 × MEm, estimating the MEm to maintain CS at 98.7% of NRC (2012) estimate. In summary, results showed that the MEm to maintain BW and CS for PIC sows during mid-gestation was below 80% and at 98.7%, respectively, of NRC (2012) estimated requirement.

Faecal pH throughout the reproductive cycle of sows in commercial pig herds.

Despite the importance of swine intestinal health, there are no easy-to-use and cost-efficient methods to evaluate it under field conditions for sows. To provide some indication about intestinal health, pH of faeces could be used but reference values for the currently high-performing commercial sow breeds are missing. In response, faecal pH of healthy sows from three different herds (herd A: 230 sows, herd B: 350 sows, herd C: 500 sows) was measured throughout the reproductive cycle. Within each herd, 10 sows were selected and rectal faeces samples were collected at different time points during the reproductive cycle: day 90 of gestation, day 1, 7, 14 and 21 of lactation, 7days post-weaning and day 30 of the next gestation. In addition, data on sow body condition (back fat), feed composition and coarseness of the feed were collected. For individual pH measurements, the pH ranged from 6.30 to 7.93. However, for all herds together, the average faecal pH value of the sows throughout the reproductive cycle ranged from 6.89 to 7.15. Also, the variations due to sow and time of sampling during the reproductive cycle were low with coefficients of variation of less than 5%. The results from the pairwise comparisons of the statistical model showed that in the last stages of lactation (i.e., at day 21), significantly lower average pH values (p≤.05) are expected when compared to earlier stages of lactation (days 3 or 7), or at day 7 post-weaning or compared to day 30 of the next gestation. Bearing its limitations, our study provided reference faecal pH values from high-performing commercial sows under field conditions and as such they could be used directly in the field. Yet, further research is needed to provide more information on the factors affecting pH values throughout the reproductive cycle of the sow.

Implications of nutritional modulators in productive performance of pregnant and lactating sows

A meta-analysis was conducted with the aim to assess the use of nutritional modulators and their effects on reproductive performance of pregnant and lactating sows. Bibliographic data, experimental characteristics, and types and levels of nutritional modulators were tabulated. A total of 22,608 sows from 68 studies, published between 1989 and 2017, were included in the meta-analysis. This analysis was conducted sequentially via a graphical, correlation and variance analysis. There was no significant difference (P > 0.05) between the average feed intake and body condition of sows in groups supplemented with L-carnitine, chromium, and somatotropin. L-carnitine and chromium supplementation in pregnant sows was found to increase the number of live-born piglets by 2.3% (P < 0.05) and 4.7% (P < 0.01), respectively. Piglet weights were 5.5%, 2.8% and 3.4% higher (P < 0.05) in L-carnitine-, L-arginine-, and somatotropin-supplemented sows than those in the control sows. Somatotropin administration increased the number of weaned piglets by 9.0% (P < 0.05). Responses of body condition of sows to supplementation and the nutritional composition of diets were poorly explored in studies with nutritional modulators, which makes it impossible to reach conclusions about the efficient use of these additives for nutritional adjustments in pregnant and lactating sows. In summary, the performance of litters can be improved in sows supplemented either with L-carnitine, L-arginine, chromium or somatotropin, during gestation and lactation.

Effect of Increasing Dietary Aminoacid Concentration in Late Gestation on Body Condition and Reproductive Performance of Hyperprolific Sows.

Simple SummaryNutrition during gestation is relevant for the success of reproductive sows and the late pregnancy is an especially critical period. Currently, the usual feeding management includes only one diet supplied at different levels through pregnancy and it could not be enough. Additionally, modern sows are producing large litters; their requirements are probably higher than those of commercial sows and they have to be met. With the current study, it can be concluded that a high level of amino acids in the diet provided approximately during the last month of gestation (around 10 g of standardized ileal digestibility lysine/kg of feed, with the remaining essential AA following the ideal protein concept) could be a strategy to improve the sow body condition and the reproductive performances.A total of 62 highly prolific Danbred sows was used to evaluate the implications of increasing dietary amino acid (AA) concentration during late gestation (from day 77 to 107 of pregnancy) on body condition and reproductive performances. Sows were assigned to one of the two treatments (n = 31, with similar number of sows in the second-, third- and fourth-cycle); control diet (containing 6 g of standardized ileal digestible lysine -SID Lys-)/kg) and high AA level (containing 10 g SID Lys/kg and following the ideal protein concept for the remaining essential AA). On day 108 of pregnancy, animals were moved to the farrowing-lactating facilities where they spent until weaning receiving a common standard lactation diet. After farrowing, litters were standardized to 13 piglets each. At 107 d of gestation, backfat depth was thicker in sows fed high AA concentration than in those fed control diet (p < 0.0001) but these significant differences disappeared at weaning (p > 0.05). Additionally, at farrowing, the litter size (p = 0.043) and weight (p = 0.017) were higher in sows fed high AA level. It can be concluded that the increase in the AA content in the feed during the last month of gestation could improve the body condition of the sows and their performance results.

Influence of the metabolic state during lactation on milk production in modern sows

Selection for prolificacy in sows has resulted in higher metabolic demands during lactation. In addition, modern sows have an increased genetic merit for leanness. Consequently, sow metabolism during lactation has changed, possibly affecting milk production and litter weight gain. The aim of this study was to investigate the effect of lactational feed intake on milk production and relations between mobilization of body tissues (adipose tissue or skeletal muscle) and milk production in modern sows with a different lactational feed intake. A total of 36 primiparous sows were used, which were either full-fed (6.5 kg/day) or restricted-fed (3.25 kg/day) during the last 2 weeks of a 24-day lactation. Restricted-fed sows had a lower milk fat percentage at weaning and a lower litter weight gain and estimated milk fat and protein production in the last week of lactation. Next, several relations between sow body condition (loss) and milk production variables were identified. Sow BW, loin muscle depth and backfat depth at parturition were positively related to milk fat production in the last week of lactation. In addition, milk fat production was related to the backfat depth loss while milk protein production was related to the loin muscle depth loss during lactation. Backfat depth and loin muscle depth at parturition were positively related to lactational backfat depth loss or muscle depth loss, respectively. Together, results suggest that sows which have more available resources during lactation, either from a higher amount of body tissues at parturition or from an increased feed intake during lactation, direct more energy toward milk production to support a higher litter weight gain. In addition, results show that the type of milk nutrients that sows produce (i.e. milk fat or milk protein) is highly related to the type of body tissues that are mobilized during lactation. Interestingly, relations between sow body condition and milk production were all independent of feed level during lactation. Sow management strategies to increase milk production and litter growth in modern sows may focus on improving sow body condition at the start of lactation or increasing feed intake during lactation.

372 Dam body condition during lactation influences piglet growth and maturation pre-finishing

Abstract We previously reported, piglets reared by fat sows, weighed less during lactation, but were heavier by 45 d of age in comparison to piglets reared by thin or moderate sows. The objective of the current study was to evaluate weight and body condition during pre-finishing and age at puberty of gilts in relation to body condition of their dams at weaning. Eight weekly farrowing seasons (parities 1–4, n = 157 litters) were used to evaluate sow body condition (weaning) and piglet growth. Sows were categorized as thin, moderate, or fat by last rib caliper measurement at weaning. Individual pig weights were recorded at approximately 100 and 145 d of age. Additionally at 145 d of age, 10th rib backfat and loin eye were measured on a subset (n = 567) of pigs and first estrus was monitored in gilts reserved for breeding selection (n = 176). Pigs reared by fat sows tended (P &amp;lt; 0.10) to be heavier at 145 d of age (90.6 ± 0.75 kg) when compared to pigs reared by thin or moderate sows (89.0 ± 1.48 kg and 88.5 ± 0.82 kg, respectively). Tenth rib backfat during finishing was not different in pigs reared by fat or thin sows (10.0 ± 0.09 mm and 9.8 ± 0.27 mm, respectively); and tended (P &amp;lt; 0.10) to be less in pigs reared by moderate sows (9.7 ± 0.09 mm) than in pigs from fat sows. Tenth rib loin eye area was similar. Gilts developed in litters from thin sows tended (P &amp;lt; 0.10) to have an early age at puberty in contrast to gilts from moderate or fat sows (182.5 ± 3.82 d vs 189.7 ± 2.49 d and 192.2 ± 1.94 d, respectively). Body condition of sows at weaning did not adversely affect pre-finishing pig growth, however pubertal development was improved in gilts from thin sows.

Hot environment on reproductive performance, immunoglobulins, vitamin E, and vitamin A status in sows and their progeny under commercial husbandry.

Hot environments can affect feed intake and lactation, and the subsequent unavailability of important micronutrients to the newborn piglet can impair piglet growth, reduce the viability of newborn piglets and limit their subsequent performance. This work addresses the effects of hot environments (summer season) upon the reproductive performance of sows during gestation and lactation as well as on the serum levels of vitamins and the concentration of immunoglobulins in their litters in comparison with the winter season. Fourteen sows were evaluated over 100 ± 2 days of gestation in each season. The temperature and humidity index (THI) was used as an indirect measure of heat stress during gestation. The reproductive performance, milk yield, and body condition of the sows were recorded. The concentrations of vitamin E and vitamin A in piglets and in sow serum, colostrum, milk and feed were determined by HPLC; immunoglobulins were assessed by an ELISA. The THI index indicated that animals were subject to heat stress only in during the summer. Although the effect was not significant, there were a lower number of piglets at birth and at weaning and the milk yield in summer compared with winter. There was no difference (p > 0.05) in the body condition of sows between seasons. Season had an effect (p < 0.05) on the vitamin A concentration of postpartum sow serum (0.29 μg/mL in winter vs 0.21 μg/mL in summer) and on the vitamin E concentration before birth (2.00 μg/mL in winter vs 0.90 μg/mL in summer). Vitamin E in milk was higher (p < 0.05) in winter than in summer (2.23 vs 1.81 μg/mL). Serum levels of vitamins A and E in piglets at birth were lower (p < 0.05) in winter than in summer. The concentrations of immunoglobulins (IgG and IgA) in colostrum and milk were similar between seasons (p > 0.05), but the IgA in piglet serum was higher in winter than in summer (p < 0.05). High temperatures produced heat stress in sows, which affected certain aspects of production that can be translated into economic losses for this sector.