Litter Weaning Weight Research Articles

Dietary supplementation with pterostilbene activates the PI3K-AKT-mTOR signalling pathway to alleviate progressive oxidative stress and promote placental nutrient transport

BackgroundProgressive oxidative stress easily occurs as a result of a gradual increase in the intensity of maternal metabolism due to rapid foetal development and increased intensity of lactation. However, studies on the effects of processive oxidative stress on nutrient transport in the placenta have received little attention. The present study was conducted on sows at 85 days of gestation to study the effects of pterostilbene (PTE) on maternal oxidative stress status and placental nutrient transport.ResultsPTE increased the antioxidant capacity and immunoglobulin content in mothers’ blood and milk, reduced the level of inflammatory factors, and improved the nutrient content of milk. PTE also reduced sow backfat loss and the number of weak sons, and increased piglet weaning weight and total weaning litter weight. We subsequently found that PTE enhanced placental glucose and fatty acid transport and further affected glycolipid metabolism by increasing the expression of LAL, PYGM, and Gbe-1, which activated the PI3K phosphorylation pathway. Moreover, PTE addition altered the relative abundance of the Firmicutes, Proteobacteria, Parabacillus, and Bacteroidetes-like RF16 groups in sow faeces. PTE increased the levels of acetate, propionate, butyrate and isovalerate in the faeces.ConclusionsThese findings reveal that the addition of PTE during pregnancy and lactation mitigates the effects of processive oxidative stress on offspring development by altering maternal microbial and placental nutrient transport capacity.Graphical

Association Analysis of METTL23 Gene Polymorphisms with Reproductive Traits in Kele Pigs.

Methyltransferase-like 23 (METTL23) is a kind of RNA methyltransferase that catalyzes the methylation transfer to the N6-adenosine of RNA, serving as one of the key mediators in this process. However, the METTL23 gene has been poorly researched in pigs. In this study, we investigated the genetic effects of METTL23 single-nucleotide polymorphism(SNPs) on reproductive traits in Kele pigs. The DNA was extracted from 228 healthy multiparous Kele sows, and Sanger sequencing revealed three SNPs, g.4804958 G > T (intron 2), g.4805082 C > T (exon 2), and g.4806821 A > G (exon 3). The polymorphism information content (PIC) for each SNP was 0.264, 0.25, and 0.354, indicating moderate polymorphism (0.25 < PIC < 0.5) and providing genetic information. Linkage disequilibrium analysis showed no strong linkage disequilibrium between the three SNPs. The association analysis revealed that in the SNP g.4804958 G > T individuals with the GG genotype had a significantly higher number of piglets born alive, litter birth weight, number of weaned piglets, and weaning litter weight compared to those with the TT genotype (p < 0.05). Individuals with the GG genotype in the SNP g.4806821 A > G group had significantly higher litter birth weight and average birth weight than those with the AA genotype (p < 0.05). The H4H4 diplotype showed significant effects on the number of piglets born alive, litter birth weight, number of weaned piglets, weaning litter weight, and weaning weight (p < 0.05). Together, the METTL23 gene could be used as a candidate gene for the selection of reproductive traits in Kele pigs.

PSIV-19 Effects of Flavolac feed top dress in lactation on sow body weight change and litter performance

Abstract A total of 271 mixed parity sows (PIC 1050) were used to evaluate the effect of feeding Flavolac in lactation diets on sow farrowing performance and litter growth performance during summer conditions. Flavolac (Agroceres Multimix; Rio Claro, Sao Paulo, Brazil) is a commercial product containing several compounds, including amino acids, antioxidants, botanicals, direct fed-microbials, and vitamin-like compounds, that individually have previously been shown to improve litter weaning weight or preweaning mortality. However, there are no published data on the benefit when these compounds are used in combination. The experiment was conducted at a commercial sow farm located in northwest Texas. At approximately d 112 to 114 of gestation, sows were moved to the farrowing house, and randomly allotted to 1 of 2 treatments based on parity and caliper score. Treatments consisted of a control diet (no Flavolac) or the control diet with an added Flavolac top-dress (80 g/d in a single feeding). Sows were weighed before entering the farrowing house and at weaning. Sows were provided approximately 1.8 kg per day of a common lactation diet without Flavolac pre-farrowing. After farrowing, sows were provided ad libitum access to lactation feed. Application of treatments began after cross fostering, approximately 24 h post-farrowing. The weaning age averaged approximately 21.3 d. There was no evidence of differences (P &amp;gt; 0.10) in sow body weight (BW) at entry, weaning, or overall BW change (Table). There was no evidence of differences (P &amp;gt; 0.10) for sow entry caliper, weaning caliper score, caliper score change, or average daily lactation feed disappearance. In addition, there was no evidence of differences (P &amp;gt; 0.10) in total litter or piglet birth weight. However, administration of Flavolac tended (P &amp;lt; 0.10) to increase litter weaning weight, total litter weight gain, and litter average daily gain. The inclusion of Flavolac led to a tendency (P = 0.091) for a reduction in pre-weaning mortality and therefore, an improvement in percentage of pigs weaned relative to those on d 2. In summary, inclusion of Flavolac during the lactation period resulted in a tendency for reduced pre-weaning mortality and tended to improve total litter weight gain, and thus litter weight at weaning.

12 Effects of increasing SID lysine (Lys) and metabolizable energy (ME) levels of lactation diets fed to young and multiparous sows

Abstract Providing insufficient lysine to lactating sows can reduce piglet performance and subsequent farrowing performance of sows. Current SID lysine and ME recommendations for lactating sows are approximately 60 g/d and 20 Mcal/d, respectively. Because of variations in feed intake during lactation, a portion of sows do not meet recommended Lys intake levels. There is no clear understanding of the Lys:Calorie ratio when dietary energy is increased in the summer to ensure adequate caloric intake. The objective was to evaluate a potential advantage of feeding diets with SID Lys and energy levels that exceed recommendations to lactating sows. A total of 855 sows were fed during the summer of 2023 in 2×2 factorial arrangement of treatments in a randomized complete block design. Factors included SID lysine [low (0.85%) vs high (1.11%)] and ME [low (3,183 kcal/kg) vs high (3,334 kcal/kg)]. Diets were formulated to deliver 61 g of SID lysine at 0.85% inclusion to sows that consume 7.2 kg of complete feed per day. Primary outcome variables were sow body composition, lactation average daily feed intake (ADFI), average piglet weaning weight, and pre-wean mortality. There were no interactions between treatments (P &amp;gt; 0.05). SID Lys intake was 61.2 and 76.4 g/d for low and high Lys, respectively (P &amp;lt; 0.01). ME intake was 21.9 and 23.4 Mcal/d for low and high energy, respectively (P &amp;lt; 0.01). Contrary to expectations, ADFI did not differ (P = 0.25) between sows fed the low- and high-energy diets, however, sows fed low lysine consumed 0.29 kg more feed (P &amp;lt; 0.01) per day compared with sows fed high lysine. There were no differences (P ≥ 0.70) in the number of piglets born alive for any treatment group. Sows fed high energy had 0.27 fewer (P &amp;lt; 0.01) still-born piglets per litter compared with sows fed low energy. Pre-wean mortality was also reduced (P = 0.05) by 0.76 percentage units in litters of sows fed the high-energy diet compared with litters of sows fed the low energy. Lysine level had no effects on farrowing and litter performance (P &amp;gt; 0.05). Litters from sows fed the high-energy diet gained 1.2 kg more (P = 0.05) body weight during lactation and tended to result in litter-weaned weights that were 1.5 kg heavier (P = 0.06) than litters from sows fed the low-energy diet. Feeding a diet with a greater lysine concentration during lactation reduced feed intake but did not affect litter performance. In contrast, increasing dietary energy immediately before farrowing and during lactation did not affect sow feed intake but reduced pre-wean mortality and resulted in fewer still-born piglets, greater litter gains, and heavier litter weaning weights.

278 Phytogenic feed additive increased sow lactation average daily feed intake, litter weaning weight, and subsequent conception rate when fed in summer environmental conditions

Abstract An experiment was conducted to test the hypothesis that feeding a phytogenic feed additive (Fresta F, Delacon, Austria) to sows during lactation would increase lactation average daily feed intake (ADFI) during natural heat stress from summer environmental conditions. At the time of entry to lactation facilities, 192 sows were randomly allotted by parity and within farrowing batch to one of two treatments. A basal lactation diet based primarily on corn, soybean meal, and dried distiller’s grains with solubles (DDGS) served as the control treatment, whereas the test treatment contained 0.04% phytogenic feed additive at the expense of corn. Before farrowing, sows were limit fed, but once farrowing occurred, sows were provided with ad libitum access to feed. Individual feed disappearance was recorded daily, and sow was considered the experimental unit. Sow body weights (BW) and ultrasound backfat thickness were recorded at the time of entry to and exit from the lactation facilities. Litter weights were recorded at birth and at weaning, and litter inventories were recorded at birth, upon completion of cross-fostering within treatment, on d 5 of lactation, and at weaning. Ultimately, 185 sows completed the study and were included in statistical analyses. Data were analyzed using the lme4 package of R 4.1.2, and the statistical models included the fixed effect of treatment and the random effects of parity and farrowing batch. Data were assumed to be normally distributed, except for pig survival and conception rate, which were analyzed using generalized linear mixed models specifying a binomial distribution. Total and live litter size did not differ at birth, nor did litter birth weight (Table 1). Inclusion of the phytogenic feed additive increased (P &amp;lt; 0.05; ADFI in lactation from 6.21 to 6.74 kg per day. In turn, the phytogenic feed additive tended (P &amp;lt; 0.10) to increase litter wean weight, which was driven by numerically increased piglet survival (87.47% for control and 89.37% for phytogenic, P = 0.126) and a tendency (P &amp;lt; 0.10) for increased average pig weaning weight. Sow BW did not differ at entry to lactation, though sow weight at weaning tended to be greater (P &amp;lt; 0.10) when the phytogenic feed additive was fed. The phytogenic feed additive also increased (P &amp;lt; 0.05) subsequent conception rate from 88.7 to 97.8%. In conclusion, feeding a phytogenic feed additive during summer conditions increased lactation feed intake, which resulted in increased weaning weight and improved subsequent conception rate.

287 The effect of cooling pad and Moringa oleifera on lactating sows under heat stress

Abstract Lactating sows and their litters are particularly vulnerable to heat stress (HS). HS decreases sow fertility, feed intake, milk production, and litter growth. Approaches are needed to mitigate the negative effects of HS on animal welfare and reduce oxidative damage to tissues associated with HS. Recently, electronic cooling pad (ECP) were designed to remove heat through conductive cooling. The objective of this study was to test the efficacy of ECP and feeding an antioxidant, Moringa oleifera (4% of the diet, M), to sows from late gestation to weaning on their welfare and production performance. A study was conducted using a 2 by 2 factorial arrangements of treatments with mixed parity Yorkshire x Landrace sows (n = 48) mated to Duroc sires. The sows were exposed to moderate HS conditions from gestation d 100 to d 21 of lactation (weaning). To achieve moderate HS analogous to a summer day, farrowing room temperature was increased incrementally from 800 to 1100 h to 32º C and slowly decreased to 26 ºC from 1700 to 2000 h. Sows were limit-fed their specific diets during gestation (1.36 kg 2X/d) and fed for ad-libitum feed intake post farrowing. Treatments included HS+control corn-soy meal diet (CS), HS+M, ECP+CS, ECP+M (n = 12/treatment). Sow RR and RT were measured four times daily (0600, 1300, 1600, 1900 h) and sow feed intake during lactation was measured along with body weight (BW) change from farrowing to weaning. Birth litter size was determined, and growth of standardized litters (n = 13 piglets/sow) was measured. Milk was collected during active farrowing (d 0) and on d 3 and d 14 post-farrowing and analyzed for macronutrient content. The use of ECP decreased lactating sow RR (Lsmeans HS = 66.5 bpm, ECP = 28.2 bpm, P ≤ 0.0001), RT (Lsmeans HS = 39.2 ºC, ECP = 38.8 ºC, P = 0.003), and lactation BW loss (Lsmeans HS = -21.67, ECP = -5.1 kg P = 0.002). ECP by time-of-day interactions (P &amp;lt; 0.01) existed for RR and RT with ECP having a greater impact from 1300 to 1900 h than at 0600 h. ECP increased lactation feed intake (P &amp;lt; 0.02). An ECP by diet interaction (P = 0.0004) indicated ECP increased lactation feed intake for the sows fed the CS diet (6.48 kg/d vs 4.42 kg/d, P = 0.0004) but did not affect feed intake of sows fed the M diet. Treatment did not affect litter weaning weight (P = 0.14). M increased percent fat in milk (Lsmeans M = 12.28, CS = 11.06, P = 0.05) across all days of lactation. The reduction in sow RR and RT combined with increased feed intake and decreased loss of BW during lactation indicate that ECP improved sow wellbeing in the HS environment. Neither cooling nor M affected litter growth, despite increased fat content of milk of M supplemented sows and increased feed intake of ECP-CS sows.

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 &amp;lt; 0.01), but increased their body weight gain during gestation (P &amp;lt; 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.

Reproductive and productive performance of hair sheep in a semi-intensive system in southeastern Mexico

Productivity measured as kilograms of lamb weaned per ewe is a composite trait of economic importance and can be used as selection criterion of maternal breeds. The objective of this study was to estimate the reproductive, preweaning growth and productivity performance of hair breed ewes, and the effect some nongenetic factors influencing them under semi-intensive conditions in southeastern, Mexico. Information of purebreds and crossbred ewes and their lambs was used to develop a composite productivity index. The final mixed model used (except for age at first lambing, AFL), included the fixed effect of breed group, year (Y, 2016-2019) and season of lambing (dry, rainy and wind and rainy), lambing number (1, 2, … ≥ 5), litter size (LS, single and double for weaning traits), and the random effects of ewe within breed group and residual error. Except for the AFL, the effect of the breed group and all other non-genetic factors were significant (P &lt; 0.0100). No breed or crossbred was superior for all traits studied, yet Katahdin breed (K) excelled the most, despite of its reproductive performance. Traits in the productivity index (litter size at lambing, adjusted litter weaning weight and lambing interval) could not be used as an optimal indicator for the identification of the best breed for crossbreeding. The K showed the best maternal ability, except for lambing interval and AFL, influenced by all non-genetic factors which could be improved by sound flock management.

Effects of maternal methyl donor intake during pregnancy on ileum methylation and function in an intrauterine growth restriction pig model

BackgroundIntrauterine growth retardation (IUGR) affects intestinal growth, morphology, and function, which leads to poor growth performance and high mortality. The present study explored whether maternal dietary methyl donor (MET) supplementation alleviates IUGR and enhances offspring’s growth performance by improving intestinal growth, function, and DNA methylation of the ileum in a porcine IUGR model.MethodsForty multiparous sows were allocated to the control or MET diet groups from mating until delivery. After farrowing, 8 pairs of IUGR and normal birth weight piglets from 8 litters were selected for sampling before suckling colostrum.ResultsThe results showed that maternal MET supplementation tended to decrease the IUGR incidence and increased the average weaning weight of piglets. Moreover, maternal MET supplementation significantly reduced the plasma concentrations of isoleucine, cysteine, urea, and total amino acids in sows and newborn piglets. It also increased lactase and sucrase activity in the jejunum of newborn piglets. MET addition resulted in lower ileal methionine synthase activity and increased betaine homocysteine S-methyltransferase activity in the ileum of newborn piglets. DNA methylation analysis of the ileum showed that MET supplementation increased the methylation level of DNA CpG sites in the ileum of newborn piglets. Down-regulated differentially methylated genes were enriched in folic acid binding, insulin receptor signaling pathway, and endothelial cell proliferation. In contrast, up-regulated methylated genes were enriched in growth hormone receptor signaling pathway and nitric oxide biosynthetic process.ConclusionsMaternal MET supplementation can reduce the incidence of IUGR and increase the weaning litter weight of piglets, which may be associated with better intestinal function and methylation status.

The moon cycle influences reproductive and productive traits in guinea pigs (Cavia porcellus) from a tropical Andean area

ABSTRACT There is currently innumerable evidence showing that the lunar cycle affects various reproductive aspects in farm animals. However, there is very little information on the effect of the lunar cycle on productive traits in these species. A retrospective study was conducted (2015–2018) to evaluate the influence of the lunar cycle on some reproductive and productive traits in a guinea pig (Cavia porcellus) production system in the southern Andean region of Ecuador. A total of 7352 productive and reproductive records of guinea pig females housed in 3 m2 cages with a breeding male were analyzed. The following variables were considered: offspring sex ratio, litter size per cage, number of weaned guinea pigs, mortality, individual and litter weaning weight of guinea pigs, and calving frequency. The lunar cycle was split into eight periods of ~3.7-d length each. Data were analyzed by logistic regression and general linear model, and means were compared by the least mean squares method of the SAS. The offspring sex ratio was not correlated to the lunar cycle. The lunar cycle at mating and calving influenced the litter size per cage, number of weaned, and mortality of guinea pigs. The individual and litter-weaning weights were influenced by the lunar cycle at calving. The frequency of calving was greater around the new and full moon than in the remaining periods of the lunar cycle. In conclusion, the lunar cycle influenced several productive and reproductive traits in guinea pigs, such as litter size, mortality, number of pups weaned, and individual and litter weaning weights. This valuable information may have practical applications in management of guinea pig production systems.

PSIII-20 Impact of Prefarrow Fat Supplementation on Piglet Survival and Subsequent Reproduction

Abstract Past research (40+ years ago) suggests feeding fat to sows before parturition and during lactation improves piglet energy stores, sow colostrum fat percentage, sow milk fat percentage and piglet survival. Therefore, the objective was to evaluate the impact of sow fat feeding on piglet survival and throughput in a modern production system. Data were collected from 1,866 sows at a 3,600 sow commercial farm in eastern North Carolina between May and August. Sows were randomly assigned to one of four treatments from day 108 of gestation until farrowing (no supplementation; Control), supplemented with 227g or 454g of soybean oil per day, or supplemented with 227g of coconut oil per day. Oil sources were top dressed daily with 2.27kg of lactation diet. After farrowing, sows had ad libitum access to the lactation diet. At birth, piglets received a colored ear tag corresponding to prefarrow diet. Traits recorded included total number of piglets born, stillborns, crossfosters, number weaned, piglet survival (number weaned ÷ total number born), litter weaning weight, lactation length, whether a sow farrowed a subsequent litter, subsequent total number born, subsequent number born alive, subsequent stillborns, Knauer sow body condition caliper score prefarrow and sow caliper score at weaning. Linear models were used in statistical analysis. Fixed effects included sow prefarrow diet, parity, contemporary group and location of the sow within the farrowing room. Covariates were included when applicable. Results are shown in Table 1. Stillborns and stillborn percentage did not differ (P &amp;gt; 0.05) between dietary treatments. Yet sows supplemented with soybean oil tended (P = 0.10) to have fewer stillborn piglets (0.06 piglets) than Control sows. No differences (P &amp;gt; 0.05) in piglet survival across dietary treatments were observed. Sows supplemented with soybean or coconut oil prefarrow had greater (P &amp;lt; 0.05) subsequent total number born (13.71 vs. 13.31 piglets) and tended (P = 0.07) to have greater subsequent number born alive (13.07 vs. 12.72 piglets) than Control fed sows. Accordingly, sows supplemented with soybean oil tended (P = 0.08) to have more subsequent total number born (13.69 vs. 13.31 piglets) and tended (P = 0.09) to have greater subsequent number born alive (13.07 vs. 12.72 piglets) than Control fed sows. No differences (P &amp;gt; 0.05) in sow body condition loss during lactation were observed between dietary treatments. In summary, prefarrow fat supplementation did not impact piglet survival but did enhance subsequent litter size. The authors would like to thank the United Soybean Board for funding projects designed to enhance pig farmer profit.

Estimation of crossbreeding and genetic parameters for reproductive traits of Boer x Central Highland goats in Ethiopia.

Additive genetic and non-additive parameters for reproductive traits of Boer x Central Highland goats were estimated. Pedigree and performance records comprised of Central Highland and their crosses with Boer goats were collected from 2009 to 2018 in the Sirinka Agricultural Research Center sheep and goat breeding station. Least-squares means for genotypes were obtained using a general linear model procedure in SAS. To estimate crossbreeding parameters, breed additive, heterotic, and recombination effects were fitted as fixed covariates instead of genotypes. Variance, heritability, and repeatability estimates were estimated through the AI-REML algorithm using WOMBAT software. Genotype did not significantly (P>0.05) influence most of the reproductive traits studied except for gestation length. The additive effect for litter size at birth (LSB), total litter birth weight (LBW), total litter weaning weight (LWW), litter size at weaning (LSW), and gestation length (GL) was estimated to be -0.004 kid, 0.08 kg, -3.18 kg, -0.54 kid, and 3.69 days, respectively. The contribution of heterosis to LSB, LWW, and GL of crossbred goats was negative, while the estimates for LBW and LSW were positive. However, Boer goats' heterosis effect and direct additive contribution to reproductive traits were insignificant (P>0.05) except for LSW. The recombination effect was negligible and not significant (P>0.05) for all traits examined. The direct heritability estimate for LSB, LWB, LWW, LSW, and GL were 0.050, 0.098, 0.086, 0.018, and 0.00, respectively. The repeatability estimates for LSB, LWB, LWW, LSW, and GL were 0.149, 0.116, 0.099, 0.086, and 0.061, respectively. The result indicates that improvement in reproductive traits would not be expected by crossing Boer with Central Highland goats. In addition, heritability estimates indicate that the improvement of reproductive traits through selection will be small, and the repeatability estimates indicate that multiple records have to be used to make a decision of culling or selection.

Estimation of heritabilities and additive genetic correlations for reproduction traits in swine: insights for tropical commercial production systems using multiple trait animal models.

This study was to estimate heritabilities, additive genetic correlations, and phenotypic correlations between number of piglets born alive (NBA), litter birth weight (LTBW), number of piglets weaned (NPW) and litter weaning weight (LTWW) in different parities of Landrace (L), Yorkshire (Y), Landrace×Yorkshire (LY), and Yorkshire×Landrace (YL) sows in a commercial swine operation in Northern Thailand. Two models were utilized, a single trait repeatability model (RM) and a multiple trait animal model (MTM). The RM assumed reproductive records from different parities to be repeated values of the same trait, whereas the MTM assumed these records to be different traits. The two models accounted for the fixed effects of farrowing year-season, genetic group of the sow, heterosis, and age at first farrowing, and the random effects of sow, boar, and residual. Heritability estimates from RM were 0.02±0.01 for NBA, 0.10±0.01 for LTBW, 0.04±0.01 for NPW, and 0.11±0.01 for LTWW. Heritability estimates from MTM fluctuated across parities, ranging from 0.04±0.01 in parity 2 to 0.09±0.02 in parity 4 for NBA, 0.07±0.02 in parity 2 to 0.16±0.02 in parity 3 for LTBW, 0.04±0.02 in parity 4 to 0.08±0.01 in parity 1 for NPW, and 0.16±0.02 in parity 1 to 0.20±0.02 in parity 2 for LTWW. Additive genetic correlation estimates from MTM were also variable, ranging from 0.29±0.24 between NBA in parity 1 and NBA in parity 2 to 0.99±0.05 between LTWW in parity 3 and LTWW in parity 4. The findings of this study highlight the advantage of using MTM for the genetic improvement of reproductive traits in swine and contribute to the development of sustainable swine breeding programs in Thailand.

Trends and status of rabbit production and research in Zambia

Rabbit production has the potential to help alleviate poverty levels through job creation, income from the sales of rabbits and their products, and a supply of nutritional food, given its urban and peri-urban functionality. However, not much is known about rabbit production and productivity in Zambia. This study is a rapid survey to document rabbit production systems, management practices and provide estimates of rabbit productivity in Lusaka, Zambia. Three production systems (extensive, semi-intensive, and intensive) were determined given the following criteria: breeds and number reared, housing provided, feed supplied, management practices and marketing of rabbits and by-products. Most producers practiced extensive production system, rearing few local and crossbred rabbits fed mostly vegetables, and housing was made of locally available wood materials and or on deep litter. The intensive production system, however, involved purebreds such as New Zealand White (NZW), Chinchilla (CH), California White (CA), Dutch (DU) and Flemish Giant (FG) and their crosses, with numbers ranging between 50 and 100 breeding animals raised in individual metal cages fed hay and pelleted concentrate feed. Mortality was lower given the conducive environment and high management practices that reduced contact with faecal droppings and allowed urine to be collected for sale. The semi intensive production system lies in the middle and is pivotal to improving productivity in the rabbit industry. Mean performances reported were litter size at birth (3.3, 5.2, 6.4), litter weight at birth (105g, 225g, 410g), litter size at weaning (1.9, 4.1, 5.7), litter weaning weight (650g, 1955g, 3256g) and average mature weight (1510g, 2120g, 2825g) for the extensive, semi intensive and intensive productions systems accordingly. The two major challenges were the limited source of breeding animals, which predisposes the sector to a high level of inbreeding and inadequate veterinary care, leading to a high mortality of over 30%. The government is encouraged to develop a national rabbit development programme that will address the above-mentioned challenges.

183 Sow Location Within Farrowing Room Impacts Reproduction During Heat Stress

Abstract The objective was to evaluate the impact of sow location, within farrowing room, on reproduction during periods of heat stress. Data were collected on 1,866 sows at a 3,600-sow commercial farm in eastern North Carolina from May to August 2021. In the farrowing buildings, evaporative cool cell pads cooled the air entering the hallway. Cooled air, from the hallway, then entered the farrowing rooms through inlets at the front of the room and was pulled through the room by fans in the back of the farrowing room. For data analysis, each farrowing room was divided into four zones. Zone 1 included the sows at the front of the farrowing room near the inlets letting in cooled air. Zone 4 included sows at the back of the room where air exited the building through fans embedded within the wall. Zones 2 and 3 were intermediate. Each farrowing room on the farm housed between 18 and 36 sows. After farrowing, sows had ad libitum access to the lactation diet. Traits included piglet survival (number weaned ÷ total number born) the percentage of sows conceiving by 7 days after weaning, subsequent total number born, subsequent number born alive, subsequent stillborns, sow caliper score prefarrow, sow caliper score at weaning and sow caliper lactation loss. Results are shown in Table 1. Piglet survival was greater (P &amp;lt; 0.05) for sows that farrowed at the front of the room near the cool air inlets. Similarly, litter weaning weight was heavier (P &amp;lt; 0.05) near the cool air inlets relative to the back part of the farrowing room. The percentage of sows that conceived by 7 days after weaning, and farrowed, was linearly associated (P &amp;lt; 0.05) with farrowing zone. Sows near the cool air inlets lost less (P &amp;lt; 0.05) body condition and farrowed more (P &amp;lt; 0.05) piglets in the subsequent litter relative to sows in the back of the farrowing room. Results showed sows that farrowed at the front of the farrowing room lost less body condition, had greater piglet survival, heavier litter weaning weights and were more likely to be rebred and conceive by 7 days after weaning relative to sows farrowing in the back of the farrowing room.

Two-Stage Fermented Feather Meal-Soybean Meal Product Improves the Performance and Immunity of Lactating Sows and Piglets

This study aimed to investigate the effects of a two-stage fermented feather meal-soybean meal product (TSFP) on the performance, clinical blood biochemistry, and immunity of sows and piglets. TSFP was fermented by Saccharomyces cerevisiae Y10 for three days in the second stage, which showed similar results to the five-day fermentation of B. coagulans (p &gt; 0.05). Fifty hybrid sows (Duroc × KHAPS black pig) were randomly assigned into dietary supplementation groups of 2% fish meal or different levels of TSFP at 0%, 1%, 2%, or 3%. The results showed that body weight gain and feed conversion ratio of 2% and 3% TSFP groups were better than the control group and fish meal group during the gestation period (d 80–114) (p &lt; 0.05). During the lactation period, the 3% TSFP group showed the best weaning litter weight (p &lt; 0.05). In sows, interferon-γ and immunoglobulin G (IgG) of 2% and 3% TSFP groups were higher than the control group and fish meal group (p &lt; 0.05). In piglets, in groups of 2% and 3% TSFP blood urea decreased (p &lt; 0.05). The IgG of fermented groups was superior to the control group (p &lt; 0.05). The oxidative burst of phagocytes in the 3% TSFP was higher than those of the control and fish meal groups (p &lt; 0.05). In conclusion, TSFP supplementation exhibits the advantages of performance and immunity of lactating sows and piglets. Furthermore, adding 3% TSFP in the feed showed the best performance.

Feeding level during the last week of gestation can influence performance of sows and their litters in the subsequent lactation.

This study investigated the impact of feeding level during the last week of gestation on performance of sows and their litters in the subsequent lactation. A total of 48 sows were assigned to one of six feeding levels (1.8, 2.4, 3.1, 3.7, 4.3, or 5.0 kg/d) from day 108 of gestation until farrowing. Post-farrowing, all sows were fed similarly during lactation with a gradual increase in feed allowance in accordance with Danish recommendation until it reached the maximum allowance of 9 kg/d on day 17 of lactation. Plasma samples were collected from the sows during farrowing and lactation, and sow's body weight and backfat thickness, and milk samples were taken during lactation. Litters were standardized to have 13 to 15 piglets each and weighed once weekly during lactation. Plasma concentrations of urea, acetate, and butyrate in sows linearly increased (P < 0.001), while non-esterified fatty acids linearly decreased (P < 0.001) during farrowing with increasing feeding level. Moreover, concentrations of triglycerides (P < 0.001), acetate (P = 0.007), and succinate (P < 0.001) were greater in plasma collected at the onset of farrowing compared to the end of farrowing. Conversely, concentrations of glucose, urea, and butyrate (P < 0.001) were lower in plasma collected at the onset of farrowing than at the end. Sows fed 2.4 and 3.1 kg/d exhibited greater triglyceride concentrations than those fed 3.7 (P = 0.03) and 5.0 (P = 0.02) kg/d. Sows fed 1.8 kg/d during the last week of gestation had lower milk yield in wk 1 (P < 0.001) and wk 2 (P = 0.001) of lactation compared to the other groups. Additionally, litter weight gain (P = 0.04) and litter weaning weight (P = 0.007) were lower in sows fed 1.8 kg/d compared to the other groups. The greatest milk yield, litter growth, and litter size were observed in sows fed 3.7 kg/d during the last week of gestation, whereas the estimate generated by the regression model revealed that sows should have been provided with 4.0 to 4.1 kg/d as an adequate feeding level to maximize these performances in the subsequent lactation. Interestingly, feeding level during the last week of gestation did not influence feed intake during lactation. In conclusion, this study highlights the significance of adequate feed supply (4.0 to 4.1 kg/d) during the last week of gestation in order to maximize performance of sows in the subsequent lactation.

Evaluation of oxidized beta-carotene on sow and piglet immune systems, sow reproductive performance, and piglet growth.

This study aimed to determine if supplementation of oxidized-beta carotene (OxC-Beta) improved sow reproductive performance, litter growth performance, vitamin A status, and ability to alter immune cells abundance in sows and piglets, subsequent litter performance, and nursery growth performance. At approximately d 60 of gestation and through the lactation period, 194 sows (blocked by parity) were assigned to a common gestation diet or the common diet supplemented with 80ppm oxidized beta-carotene (OxC-Beta, Aviagen, Ottawa, ON, Canada). A subset of sows (n = 54 per treatment) were sampled for blood and body weight recorded at the beginning of the study, farrowing, and weaning. A blood sample was taken from a subset of piglets at birth and weaning, and all piglet weights were recorded. Blood was analyzed for vitamin A as retinol concentrations and immunoglobulin G (IgG) and immunoglobulin M (IgG) levels were assessed from the sow's blood. Twelve pigs (n = 6 per treatment) were euthanized at birth and weaning. The livers were collected and analyzed for the Kupffer cell phagocytic activity through flow cytometry. Whole blood was analyzed via flow cytometry for cluster of differentiation (CD335, CD8, and CD4). Colostrum during farrowing and milk at weaning were analyzed for IgG and IgA concentrations. Data were analyzed via SAS 9.4 using MIXED and frequency procedures where appropriate. No differences (P > 0.05) between dietary treatments were observed in sow reproductive performance, feed intake, wean to estrus interval, or piglet growth performance. No differences (P > 0.05) were observed in the plasma or liver for vitamin A. No differences (P > 0.05) were observed in the composition of the colostrum or milk. No immunological differences (P > 0.05) were observed in the piglets' liver and blood or sow antibodies in colostrum and milk. The supplementation of OxC-Beta did (P < 0.05) decrease IgM and tended (P < 0.10) to decrease IgG in sow plasma. No differences (P > 0.05) were observed in the reproductive performance of subsequent litter information from the sows. Gilt litter weaning weight and feed intake were reduced (P < 0.05) compared to sow performance. In conclusion, the supplementation of OxC-Beta at 80ppm from d 60 of gestation through lactation does not affect the reproductive performance of sows, litter growth performance, vitamin A status, piglet immune status, and antibodies or composition in colostrum and milk.

The impact of functional teat number on reproductive throughput in swine.

The objective was to evaluate the impact of functional teat number on reproductive throughput in swine. Data included 735 multiparous Landrace × Large White F1 females. Sow underlined traits consisted of total teat number (TT), functional teat number (FT), nonfunctional teat number (NFT), and number of functional mammary glands (FMG). Weaning traits were calculated for both the biological and the nurse dam. For the biological dam, litter size at weaning (LSW) included a sow's biological piglets regardless of cross-fostering. For nurse dam, number weaned (NW) included the piglets a sow weaned. For the biological dam, piglet survival (PS) was calculated as litter size at weaning / (total number born × 100). Linear regression estimates were calculated in RStudio v. 1.1.456 and variance components were estimated using GIBBS3F90. Average total number born, number born alive, TT, FT, NFT, and FMG were 14.22, 13.12, 14.43, 13.96, 0.42, and 10.7, respectively. An increase in one FT enhanced (P < 0.05) LSW by 0.32 piglets and NW by 0.33 piglets. Similarly, an increase in one FT improved (P < 0.05) PS by 1.63% and reduced (P < 0.05) preweaning mortality by 2.73%. However, an increase in one FT reduced (P < 0.05) average piglet weaning weight (WW) for biological and nurse dams by 35 and 94 g, respectively. Yet an increase in one FT enhanced (P < 0.05) litter weaning weight (LWW) for biological and nurse dams by 1.3 and 1.5 kg, respectively. Heritability estimates for TT, FT, NFT, FMG, WW, LWW, LSW, and PS were 0.25, 0.22, 0.53, 0.18, 0.21, 0.22, 0.16, and 0.18, respectively. Genetic correlation estimates between FT with TT, NFT, and FMG were 0.79, 0.09, and 0.28, respectively. Estimated genetic correlations between TT with WW, LWW, LSW, and PS were 0.37, 0.38, 0.11, and -0.19, respectively. Genetic correlation estimates between FT with WW, LWW, LSW, and PS were 0.44, 0.49, 0.39, and 0.35, respectively. Results suggest increasing functional teat number would enhance both piglet survival and reproductive throughput.

Feeding a whole-cell inactivated Pichia guilliermondii yeast to gestating and lactating sows in a commercial production system.

A total of 606 sows (PIC 1050) and their progeny (PIC 1050 × 280) were used to determine if feeding gestating and lactating sows a proprietary strain of Pichia guilliermondii as a whole-cell inactivated yeast product (WCY; CitriStim, ADM Animal Nutrition, Quincy, IL) improves sow and litter performance in a commercial production system. Once confirmed pregnant at d 35 post-breeding pregnancy check, sows were fed a basal gestation control (CON) diet (0.55% SID lysine) or the control diet fortified with 0.15% of the WCY replacing corn in the CON diet. Dietary treatments were also fed in lactation (1.05% SID lysine) once sows were moved into farrowing crates on approximately d 112 of gestation until weaning. Sows supplemented with WCY in gestation and lactation had increased total born piglets by 0.45 pigs (P < 0.04), piglets born alive (14.27 vs. 13.85; P < 0.04), and, therefore, heavier born alive litter weights (P < 0.001) compared to CON fed sows. A greater post cross-foster litter size (P < 0.001) meant that litter size at weaning was increased by 0.54 pigs when sows were fed WCY compared to CON (P < 0.001). However, litter weaning weights and 21-d adjusted litter weaning weights were similar (P > 0.158), although numerically greater, for WCY fed sows. Pigs from CON fed sows were 0.35 kg heavier at weaning compared to pigs from WCY fed sows (P < 0.001). This increase in weaning weight of pigs from CON fed sows is partially explained by their 0.93 d longer lactation (P < 0.001) and may also be due to the smaller litter size throughout lactation. The percent of litters treated for scours decreased from 38.3 to 14.2% when sows were fed WCY (P < 0.001). The distribution of birth and weaning weights was not impacted (P > 0.2461) by treatment. In conclusion, feeding gestating and lactating sows a proprietary strain of Pichia guilliermondii as a whole-cell inactivated yeast product increased the number of pigs born and weaned, and decreased the prevalence of scours during lactation.