Reproductive Performance Of Sows Research Articles

154 Impact of Post-Breeding Feeding Level on the Reproductive Performance of Sows

Abstract The objective of this study was to determine the impact of feeding sows different feed levels during the first 7 d of gestation on the reproductive performance of sows. A total of 483 sows (Camborough, PIC) were used, equally balanced by parity (3-10) and body condition score (BCS) and placed on 1 of 2 treatments after breeding. Treatments consisted of: 1) feed a common level of 1.81 kg/d regardless of BCS from breeding to d 7, then feed levels were adjusted according to BCS thereafter; and 2) adjustment of feed level at breeding according to BCS. Sows were fed either 3.63, 2.72, 2.04, or 1.59 kg/d according to their BCS (1-5), respectively. Body condition, measured by the sow caliper, was reassessed, and feed levels were adjusted as needed on d 45 and 90 of gestation. Diets consisted of a standard milo and wheat midds based gestation diet which met or exceeded NRC (2012) recommendations for nutrient levels. Feeding thin (BCS 1, 2) pregnant sows elevated feed levels from breeding to d 7 of gestation tended to reduce the return rate (% sows that returned to estrus: bred) (P = 0.098; 8.85 vs. 3.68%, respectively); but not the farrow rate (% sows that farrowed: bred; P = 0.265, 87.61 vs. 91.91%, respectively). There was no difference in litter size at farrowing (P > 0.10). In conclusion, feeding weaned sows according to body condition compared with feeding 1.81 kg/d during the first 7 d of gestation decreased the number of thin sows returning to estrus.

PSVII-9 The Impact of Increasing Dietary Manganese on the Reproductive Performance of Sows

Abstract The objective of this study was to determine the effect of dietary manganese (ProPath Mn, Zinpro Corporation) on the reproductive performance of sows. Sows (N = 39; 231 ± 8 kg) were randomly assigned to 1 of three dietary levels of Mn (CON: 0 ppm Mn; PRO20: 20 ppm Mn; PRO40: 40 ppm Mn). Experimental treatments were initiated at breeding and continued through 2 parities. Sows were blocked by parity within each farrowing group and dietary treatments were represented within each block. Data were analyzed as a randomized complete block design using the MIXED procedure of SAS with diet as a fixed effect and block as a random effect. Dietary treatment did not affect sow body weights (P > 0.10). Lactation feed intake was increased in PRO20 sows compared with CON and PRO40 sows (P < 0.05). PRO20 and PRO40 sows farrowed heavier piglets (CON 1.23 kg; PRO20 1.57 kg; PRO40 1.40 kg; P = 0.001) with improved average daily gain to weaning (CON 213 g/day; PRO20 237 g/day; 220 g/day; P < 0.05), compared with CON sows. Milk fat content (average from d 7 and 14 of lactation) was reduced in PRO20 (5.5%) and PRO40 sows (6.1%; P < 0.05) compared with CON sows (7.8%), possibly due to increased milk demand from the piglets. There were no significant differences in milk mineral concentrations during lactation or piglet tissue Mn-superoxide dismutase (MnSOD) activity at weaning (P > 0.10). On day 3 of lactation, prolactin concentrations were similar across treatments (P > 0.10), whereas progesterone concentrations tended to differ in response to Mn level (CON 23.70 ng/mL; PRO20 26.15 ng/mL; PRO40 22.10 ng/ml; P = 0.09). Supplementary dietary Mn throughout 2 gestation and lactation cycles led to increased birth weights and pre-weaning growth of piglets.

PSVII-2 Effects of Oxidized Beta-Carotene on Sow Reproduction and Piglet Growth Performance

Abstract As reproductive performance of sows in the commercial U.S. sow herd continues to improve, advancing the impact of gestation and lactation diet supplementation is critical. Beginning on d 60 of gestation through lactation, sows (blocked by parity) were assigned to a standard gestation diet (n = 88), or the standard diet supplemented with 80 ppm OxC-beta (n = 90) provided by Avivagen (Ottawa, ON, Canada) to determine if the supplementation of OxC-beta improves sow reproductive performance, litter growth performance, and alters the abundance of immune cells in sows and piglets. Blood samples were taken from a subset of sows (n = 54 per treatment) at the start of the study, at farrowing, and at weaning; and also, on a subset of piglets at birth and weaning. Also, at birth and weaning, 12 pigs (n = 6 per treatment) were euthanized, and livers were collected and subjected to flow cytometry to analyze phagocytic activity of the Kupfer cells. CD335, CD8, and CD4 populations within whole blood were assessed via flow cytometry. Colostrum at farrowing and milk at weaning were collected for analysis of IgG and IgA. Data were analyzed via SAS 9.4 using PROC GLIMMIX. No differences (P > 0.05) between dietary treatments were observed in sow reproductive performance, sow feed intake, wean to estrus interval, or piglet growth performance. No differences (P > 0.05) were observed for vitamin A in the plasma or liver. No immune differences (P > 0.05) were observed in the piglet’s liver and blood nor sow antibodies in colostrum and milk. Subsequent litter information was obtained from the sows, and no differences (P > 0.05) were observed in reproductive performance. Overall, there were no differences in sow reproductive performance, litter growth performance, and the immune system of sows and piglets of sows supplemented OxC-beta.

118 Awardee Talk: An Empirical Model of Essential Amino Acid Requirements in the Pregnant Sow

Abstract Amino acid (AA) requirements are generally considered to be the minimum needed for maximum growth or protein synthesis; however, multiple studies have shown that AA intakes above these requirements improve various body functions such as immune response, gut health, and reproduction. The objective of the current modeling approach was to estimate AA intake in gestation that considered protein synthesis as well as sow reproductive performance and offspring development, potentially increasing piglet growth and survivability. A literature review was conducted to identify studies evaluating the effects of sow AA intake during gestation on protein synthesis, sow body weight, litter size, average piglet birth weight and suckling piglet growth rate. Data from 26 empirical studies from 1989 to 2021 were selected for model development and estimation of arginine, leucine, lysine, methionine, threonine, and valine requirements. To check model accuracy and performance, a validation analysis was conducted by contrasting the model predicted lysine requirements with data from 17 published studies not used in the development of the model. The estimated lysine requirement was approximately 40% greater than the minimum lysine intake required for maximum protein synthesis. Similarly, the ratios of arginine, leucine, methionine, and valine to lysine were on average 1.60, 2.47, 0.41, and 0.79, respectively, which are 6 to 300% greater than, and the ratio of threonine to lysine was similar to, current recommendations. The validation analysis showed that the estimated lysine requirement resulted in the greatest litter size and birth weight. In addition, when compared with lysine intakes that met current recommendations, lysine intake at the estimated requirement improved colostrum and milk quality, stillborn rate, proportion of low birth weight, suckling piglet growth rate, and sow blood urea, among other metabolic variables. In conclusion, at the estimated requirements sow reproductive performance as well as piglet survivability and growth rate are improved.

121 Effects of Total Dietary Fiber Content During Gestation on Sow Reproductive Performance

Abstract The objective of this study was to investigate the effects of total dietary fiber (TDF) levels during gestation on sow and litter performance. A total of 397 (Camborough, PIC) individual-housed sows were used. Sows were balanced by parity (P4-P10) and body condition score (BCS, 1-5) at breeding and allocated to 2 treatments: Low Fiber (TDF = 9%, LF) or High Fiber (TDF = 18%, HF) with similar insoluble to soluble fiber ratios 7.4 and 7.5 respectively. During gestation, all sows were fed according to their BCS (BCS 1 and 2 = 2.7 kg/d, BCS 3 = 2kg/d and BCS 4 and 5 = 1.6 kg/d). From d 90 of gestation thin sows (BCS 1 or 2) received an additional 0.9 kg/d. During lactation sows received a common diet, 1.81 kg/d pre-farrow, and then ad libitum. Diets were milo based with wheat midds and soy hulls as fiber sources. Dietary treatments were isonutrient and isocaloric and formulated to meet or exceed NRC (2012) nutrients. Data were analyzed for main effects of treatment and within body condition category. Overall, sows that received the LF diet were heavier at placement in lactation (306.6 and 280.6 kg; P = 0.012, for LF and HF, respectively). Similarly, the estimated post-partum BW was heavier for those fed the LF diet (283.1 and 256.1 kg; P = 0.008) and at wean BW (271.3 and 257.1 kg; P = 0.003). However, sows fed a HF gestation diet tended to lose less weight during lactation (17.0 and 4.0 kg; P = 0.080). There were no differences for total born (P = 0.767), born alive (P = 0.821), stillborn (P = 0.850) or weaned pigs (P = 0.620). In conclusion, elevating TDF during gestation did not improve litter performance, but did reduce weight and body condition loss during lactation.

246 Awardee Talk: Evaluating the Impact of Essential Fatty Acids in Lactation Diets on Sow and Litter Performance

Abstract Two experiments were conducted to evaluate the effects of supplemental fat sources providing low and high essential fatty acids (EFA) in lactation diets on sow reproductive performance, piglet growth and survivability, and colostrum and milk composition. In Exp. 1, mixed parity sows (n = 91) were allotted to 5 experimental treatments arranged in a 2×2 + 1 factorial. Treatments were corn-soybean meal-based diets that contained no added fat or diets with 3% added fat as either beef tallow or soybean oil starting on d 107 or 112 of gestation. Sows were provided low EFA [linoleic acid (LA) and α-linolenic acid (ALA)] in diets without supplemental fat or with beef tallow or high EFA with soybean oil. Results confirmed that providing fat sources with high EFA can increase colostrum and milk LA and ALA content, regardless of pre-farrow time of diet consumption. However, supplemental fat did not influence litter growth performance (P > 0.05). In Exp. 2, mixed parity sows (n = 3,451) were assigned to 4 corn-soybean meal-wheat-based lactation diets with 0.5 (Control) or 3% choice white grease (CWG), 3% soybean oil (SO), or a combination of 3% soybean oil and 2% choice white grease (Combination) at d 112 of gestation to provide diets with low or high EFA. Lactation ADFI increased (P < 0.05) for sows fed the Combination and CWG diets compared with sows fed the Control or SO diet. Sows fed Combination and SO diets had greater (P < 0.05) LA and ALA intake, LA and ALA in colostrum and milk, litter weaning weights, and litter ADG than sows fed 0.5 or 3% CWG. Sow EFA intake did not affect (P > 0.10) piglet survivability or subsequent sow reproductive performance. In conclusion, increased LA and ALA intake provided by SO during lactation increased overall litter growth and weaning weights but did not affect piglet survivability or subsequent performance.

151 Impact of Feed Allotment During the Wean-To-Estrus Interval on Sow Reproductive Performance

Abstract Pork producers have recently inquired whether the allotment of feed should be greater during the wean-to-estrus interval to optimize sow performance. The objective of this experiment was to validate the amount of feed allotted to sows during the wean-to-estrus interval to optimize feed costs and farrowing performance. A total of 257 PIC 1050 (PIC, Inc., Hendersonville, TN) weaned sows were blocked to 3 body condition categories (thin, ideal, or heavy, respectively) and then randomly allotted to 1 of 2 feed quantity treatments (2.7 or 5.4 kg, respectively) on d 0. The sows used in this experiment were housed under commercial conditions and had an average parity of 3.15. One day prior to weaning, each sow was calipered to determine body condition and feed boxes were validated to determine that the desired amount of feed was actually allocated during the experimental period. Sows were fed their allotted amount of feed (2.7 or 5.4 kg, respectively) from d 0 till the sows were serviced or if the sows had not been detected in estrus until d 8. Sows were tracked through their subsequent wean to detect any downstream differences. Data were analyzed using Proc MIXED (SAS 9.4; Cary, NC) with sow as the experimental unit, treatment as the main effect, and caliper score as the block criteria. These data indicate that allocating 5.4 kg of feed did not improve wean-to-first service interval (2.7 kg = 4.4 d vs. 5.4 kg = 4.4 d; P = 0.99), farrowing rate (2.7 kg = 91.5% vs. 5.4 kg = 90.6%; P = 0.81), or total born (2.7 kg = 15.9 vs. 5.4 kg = 15.4 pigs/litter; P = 0.31). In summary, feeding greater than 2.7 kg of feed from wean-to-estrus does not improve sow performance, but does increase feed costs.

PSV-18 Time Since Last Meal Until the Onset of Farrowing Affects Survivability of Newborn Piglets

Abstract The present study aimed to investigate whether time since last meal until the onset of farrowing affects sow reproductive performance. The results are based on data records compiled from 8 batches for a total of 660 mixed parity (µ = 3.7) sows from the same commercial farm. All sows were fed standard lactation diets twice a day (7:30 AM and 4:30 PM) 1 week before expected farrowing. Time since last meal until the onset of farrowing and farrowing duration were calculated accordingly. Based on the time from the start of last meal to the onset of farrowing, sows were divided into three groups: 0-3 hours, 3-6 hours and 6-16 hours (212, 220 and 228 sows respectively). Probability of born alive, stillborn and mummified piglets were statistically analyzed by a binomial model in R. Farrowing duration of sow was not affected by time since last meal until the onset of farrowing. However, sows farrowed 3-6 hours after feeding had lowest probability of stillborn piglet compared with sows farrowed 0-3 hour and 6-16 hour after feeding (6% vs 8% and 10%; P < 0.01), greater probability of born alive was also found in sows in 3-6 hour group than the other 2 groups (92% vs 89% and 88%; P < 0.01). The probability of mummified piglet was not affected when comparing the three groups. Time since last meal until the onset of farrowing also showed no effect on litter size or litter birth weight. In conclusion, feeding sows the last meal 3-6 hours before farrowing may help improve live born and decrease stillborn piglets.

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.

Reproductive Performance, Piglet Mortality and Reproductive Health Problems of Sows in The Ejisu Municipality

A cross-sectional study was conducted among commercial pig farmers in the Ejisu Municipality to investigate reproductive performance, piglet mortality, and reproductive health problems on their farms. Questionnaires designed to obtain information on reproductive performance and reproductive health problems were administered to a total of 50 randomly selected pig farmers. Three farms were randomly selected to monitor farrowing and pre-weaning piglet mortality. The farrowing records of a minimum of 10 sows on each farm were taken, and the piglets followed up to the point of weaning by six weeks. Records of piglet mortalities and their causes were retrieved from farm records or post mortem reports. The mean litter size, stillbirth per litter, piglet birth weight (Kg), weaning to estrus interval, and gestation period were 9.5± 1.4, 1.6 ± 0.2, 1.0 ± 0.1, .7±1.0 days, and 115.1± 2.6 days, respectively. The pre-weaning mortality (%) at day 42 was 18.7 and ranged from 7.3-28.3. Within the first two days post farrowing, mechanical crushing (8.9%) of piglets by sows and piglet starvation (7.2%), while diarrhea (2.5%) and piglet anemia (1.5%) accounted for mortalities within the first two weeks of life. Reproductive health problems by frequency of occurrence included mastitis (23%), agalactia (18%), stillbirths (18%), repeat breeders (14%) and dystocia (14%). The study concluded that the reproductive performance of sows was satisfactory, while pre-weaning piglet mortality was high. It is recommended to intensify extension education on the management of piglets after farrowing.

Sow Reproductive Performance, Lifetime Performance, Their Risk Factors, Predictors and Farm-Level Factors in Farm Data Analysis

Sow Reproductive Performance, Lifetime Performance, Their Risk Factors, Predictors and Farm-Level Factors in Farm Data Analysis

Effects of Dietary Lysolecithin Supplementation during Late Gestation and Lactation on Sow Reproductive Performance, Sow Blood Metabolic Parameters and Piglet Performance.

Simple SummaryLactation is metabolically very demanding, and sows struggle to eat enough to cover their requirements. Use of lysolecithin can improve energy digestibility and retention and may be able to help sows maintain condition and performance during lactation. In the present study supplementation with lysolecithin reduced backfat loss and increased litter growth. There were also impacts of lysolecithin supplementation on glucose and urea metabolism, indicating improved nutrient digestion and absorption, potentially via leptin-regulated mechanisms.The objective of the present study was to evaluate the effects of dietary supplementation of lysolecithin in sows’ diets during the last three weeks of the gestation period and throughout the lactation period on performance and metabolic parameters. In total 60 sows were allocated to two treatments: (a) CG (control group): the sows were fed commercially control diets; (b) LLG (lysolecithin group): the sows were fed the control diets supplemented with 750 g/t of feed supplemented with lysolecithin (Lysoforte Booster DryTM, Kemin Europa N.V., Herentals, Belgium). Backfat was lower in LLG than CG at end of gestation and at weaning (p = 0.030 and 0.044, respectively), while the CG sows mobilized more backfat between day 14 to weaning (p = 0.006). Litter weight at weaning was higher in the LLG (p = 0.027). Fasted glucose levels at day 14 of lactation tended to be lower in LLG compared to CG (p = 0.074). Urea concentrations were higher in LLG than CG at day 14 (p = 0.002). Lysolecithin supplemented sows compared to the control mobilized less tissue during lactation to support lactation demands. In conclusion, lysolecithin supplementation in sows resulted in improved litter weight at weaning without an excessive catabolism of backfat tissue, most probably due to an efficient nutrient utilization, which warrants further investigation.

Effects of Dietary Choline Levels During Pregnancy on Reproductive Performance, Plasma Metabolome and Gut Microbiota of Sows.

This study investigated the effects of dietary choline levels during gestation on reproductive performance of sows. In addition, the plasma metabolome and gut microbiota of sows was studied. A total of 260 multiparous sows were allocated to five dietary treatment groups with increasing choline concentrations (1,050, 1,450, 1,850, 2,250, and 2,650 mg/kg) in a randomized complete block design. The sows were fed experimental diets from breeding until farrowing and a common lactating diet during lactation. The results showed that the backfat (BF) gain of sows during gestation, individual birth weight for total piglets born, piglets born alive, average piglet weight at weaning increased linearly (P < 0.05), whereas the within-litter birth weight variation coefficient (CV) of piglets born alive and suckling piglet mortality decreased linearly (P < 0.05) as dietary choline level increased. A quadratic effect of dietary choline level was observed for the average daily feed intake (ADFI) of sows during lactation (P < 0.05). ADFI was maximized when the dietary choline concentration reached 1,910 mg/kg. Plasma H2O2 concentration at day 30 of gestation in the 1,050 mg/kg group was greater than that in the 1,850 and 2,650 mg/kg groups (P < 0.05). Plasma metabolomics identified 46 metabolites among the three groups. Specifically, plasma concentrations of trimethylamine-N-oxide (TMAO), dopamine, and L-proline increased while 1-methylhistidine concentration decreased as dietary choline levels increased. In addition, bacterial observed species and richness (Chao 1 and ACE) at day 110 of gestation decreased as dietary choline levels increased (P < 0.05). For the gut microbiota composition, the enhanced dietary choline level decreased the abundance of phylum Proteobacteria (P < 0.05) and increased the abundance of phylum Actinobacteria (P < 0.05) at day 30 of gestation. Compared with the 1,050 mg/kg group, the abundance of genus Terrisporobacter was less in the 1,850 mg/kg group, and genera Bacillus and Cellulomonas were greater in the 2,650 mg/kg group. In summary, increasing dietary choline levels improved the birth weight, uniformity of neonatal piglets and litter performance during lactation. This may be associated with better antioxidant capability, metabolic status, and gut microbiota of sows during gestation.

Evaluation of Essential Fatty Acids in Lactating Sow Diets on Sow Reproductive Performance, Colostrum and Milk Composition, and Piglet Survivability

A total of 3,451 mixed parity sows and their litters were used to evaluate the effects of essential fatty acid intake on sow reproductive performance, piglet growth and survivability, and colostrum and milk composition. At approximately d 112 of gestation, sows were blocked by parity within farrowing room and randomly assigned to 1 of 4 experimental treatments. Lactation diets were corn-soybean meal-wheat-based and included 0.5 (Control) or 3% choice white grease (CWG), 3% soybean oil (SO), or a combination of 3% soybean oil and 2% choice white grease (Combination). Thus, sows were provided diets with low essential fatty acid (EFA; as linoleic [LA] and α-linolenic acid [ALA]) in diets with choice white grease or high EFA in diets with soybean oil. Prior to farrowing, sows were provided 4 lb/d of their assigned lactation diet and then allowed ad libitum access after parturition. Overall lactation ADFI increased (P < 0.001) when sows were fed the Combination and CWG treatments compared to sows fed the Control or diet with 3% SO. Regardless of differences among ADFI, daily LA and ALA intake of sows assigned to the Combination and SO treatments were greater (P < 0.001) than sows fed diets with lower EFA provided as CWG. There was no effect of sow EFA intake on piglet survivability from birth to 24 h or from 24 h to weaning (P > 0.10). Overall, sows consuming high EFA provided in the Combination and SO diets produced litters with greater (P < 0.05) litter gain and litter ADG during the lactation period and heavier (P < 0.001) piglet weaning weights when compared to litters from sows fed diets with low EFA provided through CWG. Lactation diet EFA composition did not influence colostrum or milk dry matter, crude protein, or crude fat content (P > 0.10). However, LA and ALA content in both colostrum and milk at weaning increased (P < 0.05) in response to increased EFA levels in diets that contained SO. There was no evidence for differences (P > 0.10) in wean-to-estrus interval, percentage of sows bred by d 7, percentage of sows bred by d 12, farrowing rate, or subsequent farrowing performance due to sow lactation EFA intake. In conclusion, increased LA and ALA intake during the lactation period from soybean oil addition increased overall litter growth and average weaning weights of pigs but did not affect piglet survivability or subsequent reproductive performance of sows.

Influence of technological factors on the reproductive performance of sows in an industrial breeder

The most important element of pork production technology is herd reproduction. Among all reproductive qualities of sows, the most important are prolificacy, heavy litter, and preservation of piglets during the suckling period. Therefore, the study of reproductive qualities of pigs is relevant to the theory and practice of pig breeding. The research was carried out under reproductive conditions in an industrial pig breeding complex. It is noted that the greatest increase in sows prolificacy is observed when the service-period is 21-28 days, i.e. when one heat is skipped, as compared to sows with a service-period of 1-7 days, i.e. without heat skipping. The highest farrowing rate was observed in groups of sows without heat skipping, but taking into account the prolificacy, the highest number of piglets was obtained in groups of sows with a service-period of 21-28 days - 33.35-34.70 animals. The survival rate of piglets in all groups of sows was 90.3%. Stillbirth rate was 0.85 heads per sow. Slight variations in this indicator from 0.79 to 0.95 were recorded depending on the service period of the sows. On average the crushed piglets amounted to 0.76 animals per nest. There were slight fluctuations from 0.73 to 0.79 depending on the service-period of the sows. Fetal mummification of fetuses was 0.37 per nest. It is noted that there is a tendency to increase the number of mummified fetuses with increasing service-period of sows. The number of mummified fetuses increases with increasing multiplicity of sows, which was observed in groups of sows with a service period of 21-28 and 45 days or more.

Lactating sows fed whey protein supplement has eventually increased the blood profile of piglets.

The intension of this study was to examine the effect of dietary whey protein supplementation on the reproduction performance, growth performance and blood profile of sow and their offspring. From Day 114 of lactation to 21days of weaning, a total of 21sows (n=7/ treatment) (Landrace×Yorkshire) were blocked according to average parity (2.4) and allocated to 1 of 3 dietary treatments: (i) CON-corn-soybean meal based basal diet, (ii) WPC-CON+0.047% WPC whey protein concentrate (WPC) and (iii) WPH-CON+0.02% whey protein hydrolysate (WPH). The reproduction performance of sows was not affected by WPC or WPH supplementation. However, piglets that were born to WPC and WPH group sows showed higher body weight at birth (p=0.057) and at weaning (p=0.018). After farrowing, WPC and WPH group sows showed decreased (p=0.043) RBC count and total iron-binding count (TIBC) (p=0.046), whereas at the end of the experiment, the blood profile including red blood cells, iron, haemoglobulin and TIBC was significantly increased (p=0.042, 0.049, 0.051 and 0.052 respectively) in WPC group piglets compared to the CON and WPH groups. Based on the positive impact on the blood profile of piglets, we conclude that whey protein supplement could serve as a potential energy source to suit lactating sows that could eventually benefit the performance of their offspring.

Comparison of Gut Microbiota and Metabolic Status of Sows With Different Litter Sizes During Pregnancy.

The experiment was conducted to compare the differences of gut microbiota and metabolic status of sows with different litter sizes on days 30 and 110 of gestation, and uncover the relationship between the composition of maternal gut microbiota during gestation and sow reproductive performance. Twenty-six Large White × Landrace crossbred multiparous sows (2nd parity) with similar back fat thickness and body weight were assigned to two groups [high-reproductive performance group (HP group) and low-reproductive performance group (LP group)] according to their litter sizes and fed a common gestation diet. Results showed that compared with LP sows, HP sows had significantly lower plasma levels of triglyceride (TG) on gestation d 30 (P < 0.05), but had significantly higher plasma levels of TG, non-esterified fatty acid, tumor necrosis factor-α, and immunoglobulin M on gestation d 110 (P < 0.05). Consistently, HP sows revealed increased alpha diversity and butyrate-producing genera, as well as fecal butyrate concentration, on gestation d 30; HP sows showed significantly different microbiota community structure with LP sows (P < 0.05) and had markedly higher abundance of Firmicutes (genera Christensenellaceae_R-7_group and Terrisporobacter) which were positively related with litter size on gestation d 110 than LP sows (P < 0.05). In addition, plasma biochemical parameters, plasma cytokines, and fecal microbiota shifted dramatically from gestation d 30 to d 110. Therefore, our findings demonstrated that microbial abundances and community structures differed significantly between sows with different litter sizes and gestation stages, which was associated with changes in plasma biochemical parameters, inflammatory factors, and immunoglobulin. Moreover, these findings revealed that there was a significant correlation between litter size and gut microbiota of sows, and provided a microbial perspective to improve sow reproductive performance in pig production.

NR1D1 targeting CYP19A1 inhibits estrogen synthesis in ovarian granulosa cells

The circadian system performs an important role in mammalian reproduction with significant effects on hormone secretion. Nuclear receptor subfamily 1 group D member 1 (NR1D1) functions as a transcriptional repressor in the circadian system and affects granulosa cells (GCs), but how it regulates estrogen synthesis has not been clarified. We investigated the effect of NR1D1 on estrogen synthesis and found that NR1D1 was highly expressed in GCs, mainly in cell nuclei. Additionally, the expression of NR1D1 and estrogen synthesis key genes CYP19A1, CYP11A1 and StAR showed rhythmic changes in porcine ovarian GCs. Activation of NR1D1 enhances its ability to inhibit the transcriptional activity of CYP19A1 by binding to the RORE on the CYP19A1 promoter, resulting in a decrease in estradiol content. Interference with NR1D1 can eliminate the transcriptional inhibition of CYP19A1 and promote the synthesis of estradiol. The results suggest that the hormone secretion of the ovary itself is also regulated by the biological clock, and any factors that affect the circadian rhythm can affect the endocrine and reproductive performance of sows, so the natural rhythm of sows should be maintained in production.

Effect of Season and Parity on Reproduction Performance of Iberian Sows Bred with Duroc Semen.

Simple SummaryThe Iberian pig is appreciated for the organoleptic and nutritional characteristics of its meat. Traditional breeding is extensive, but many farms perform intensive breeding for increased productivity. In these cases, Duroc boars are the source of semen for artificial insemination (AI). There is little information on this kind of breeding; therefore, we analyzed the records from a farm near Mérida (Spain). Our main interest was the effect of parity (number of previous farrowings) and season on the reproductive results of the farm. Sows between 2 and 4 previous farrowings showed the best fertility and prolificacy. Additionally, the results were higher for AI performed in autumn and winter, with a drop in reproductive performance earlier in the year than for other breeds, which usually decline by summer–early autumn. Increasing day length in the spring combined with higher temperatures in late spring–summer could lower performance during these periods. These results could help improve the management of Iberian sow farms.The Iberian pig is an autochthonous breed from the Iberian Peninsula highly valued for its meat. The sows are often bred as Iberian × Duroc crossings for increased efficiency. Since sow parity and season affect the reproductive performance, we evaluated two-year records from a commercial farrow-to-finish farm (live, stillborn, and mummified piglets after artificial insemination, AI). A total of 1293 Iberian sows were inseminated with semen from 57 boars (3024 AI). The effects of parity (gilts, 1, 2–4, 5–10, and >10 farrowings) and season were analyzed by linear mixed-effects models (LME). The data were fitted to cosinor models to investigate seasonal effects within parity groups. The effects of maximum daily temperature (MDT) and day length change (DLC) during spermatogenesis, pre-AI, and post-AI periods were analyzed with LME. The 2–4 group was the optimal one for parity. A seasonal effect was evident between spring–summer (lower fertility/prolificacy) and autumn–winter (higher). Cosinor showed that the seasonal drop in reproductive performance occurs earlier in Iberian sows than in other breeds, more evident in gilts. MDT negatively affected performance in all periods and DLC in spermatogenesis and pre-AI. These results are relevant for the improvement of Iberian sows’ intensive farming.

20. Impact of a bioactive mineral-based feed additive on oxidative stress and reproductive performance in sows

20. Impact of a bioactive mineral-based feed additive on oxidative stress and reproductive performance in sows