The potential for carbon dioxide removal by enhanced rock weathering in the tropics: An evaluation of Costa Rica

Tropical environments show great potential to sequester CO2 by enhanced rock weathering (ERW) of powdered mafic rocks applied to agricultural fields. This study seeks to assess carbon dioxide reduction (CDR) potential in the humid tropics (1) by experimental weathering of mafic rock powders in conditions simulating humid tropical soils, and (2) from weathering rates determined from a Holocene tropical soil chronosequence where parent material is andesitic sediments. Experimentally determined weathering rates by leaching of basaltic andesites from Costa Rica (Arenal and Barva) for 50 t ha-1 applications indicate potential sequestration of 2.4 to 4.5 t CO2 ha-1 yr-1, whereas the USGS basalt standard BHVO-1 yields a rate of 11.9 t ha-1 yr-1 (influenced by more mafic composition and finer particle size). The chronosequence indicates a rate of 1.7 t CO2 ha-1 yr-1. The weathering experiment consisted of 0.6 mm of powdered rock applied atop 12 mm of Ultisol at 35 °C. To simulate a tropical soil solution, 100-mL aliquots of a dilute solution of oxalic acid in carbonated DI water were rained onto soils over a 14-day period to simulate soil moisture in the humid tropics. Solutions were collected and analyzed by ICPMS for concentrations of leached cations. A potential ERW scenario for Costa Rica was assessed assuming that one-half of lowland agricultural kaolinitic soils (mainly Ultisols, common crop and pasture soils, excluding protected areas) were to receive 50 t ha-1 of annual or biennial applications of powdered mafic rock. With an experimentally determined humid tropical CDR rate for basaltic andesite (3.5 t ha-1 yr-1) and allowances for carbon costs (e.g. emissions from processing and delivery) that reduce CDR to a net 3.2 t ha-1 yr-1, potential annual CDR of this tropical nation is ∼2-4 million tons, amounting to ∼25-50 % of annual CO2 emissions (mainly from transportation in Costa Rica).

Intimate Partner Violence-Related Brain Injury: Unmasking and Addressing the Gaps

Intimate partner violence (IPV) is a significant, global public health concern. Women, individuals with historically underrepresented identities, and disabilities are at high risk for IPV and tend to experience severe injuries. There has been growing concern about the risk of exposure to IPV-related head trauma, resulting in IPV-related brain injury (IPV-BI), and its health consequences. Past work suggests that a significant proportion of women exposed to IPV experience IPV-BI, likely representing a distinct phenotype compared with BI of other etiologies. An IPV-BI often co-occurs with psychological trauma and mental health complaints, leading to unique issues related to identifying, prognosticating, and managing IPV-BI outcomes. The goal of this review is to identify important gaps in research and clinical practice in IPV-BI and suggest potential solutions to address them. We summarize IPV research in five key priority areas: (1) unique considerations for IPV-BI study design; (2) understanding non-fatal strangulation as a form of BI; (3) identifying objective biomarkers of IPV-BI; (4) consideration of the chronicity, cumulative and late effects of IPV-BI; and (5) BI as a risk factor for IPV engagement. Our review concludes with a call to action to help investigators develop ecologically valid research studies addressing the identified clinical-research knowledge gaps and strategies to improve care in individuals exposed to IPV-BI. By reducing the current gaps and answering these calls to action, we will approach IPV-BI in a trauma-informed manner, ultimately improving outcomes and quality of life for those impacted by IPV-BI.

Digitalization of toxicology: improving preclinical to clinical translation

Though the portfolio of medicines that are extending and improving the lives of patients continues to grow, drug discovery and development remains a challenging business on its best day. Safety liabilities are a significant contributor to development attrition where the costliest liabilities to both drug developers and patients emerge in late development or post-marketing. Animal studies are an important and influential contributor to the current drug discovery and development paradigm intending to provide evidence that a novel drug candidate can be used safely and effectively in human volunteers and patients. However, translational gaps-such as toxicity in patients not predicted by animal studies-have prompted efforts to improve their effectiveness, especially in safety assessment. More holistic monitoring and "digitalization" of animal studies has the potential to enrich study outcomes leading to datasets that are more computationally accessible, translationally relevant, replicable, and technically efficient. Continuous monitoring of animal behavior and physiology enables longitudinal assessment of drug effects, detection of effects during the animal's sleep and wake cycles and the opportunity to detect health or welfare events earlier. Automated measures can also mitigate human biases and reduce subjectivity. Reinventing a conservative, standardized, and traditional paradigm like drug safety assessment requires the collaboration and contributions of a broad and multi-disciplinary stakeholder group. In this perspective, we review the current state of the field and discuss opportunities to improve current approaches by more fully leveraging the power of sensor technologies, artificial intelligence (AI), and animal behavior in a home cage environment.

p53 inhibitor iASPP is an unexpected suppressor of KRAS and inflammation-driven pancreatic cancer

Oncogenic KRAS activation, inflammation and p53 mutation are key drivers of pancreatic cancer (PC) development. Here we report iASPP, an inhibitor of p53, as a paradoxical suppressor of inflammation and oncogenic KRAS^G12D-driven PC tumorigenesis. iASPP suppresses PC onset driven by KRAS^G12D alone or KRAS^G12D in combination with mutant p53^R172H. iASPP deletion limits acinar-to-ductal metaplasia (ADM) in vitro but accelerates inflammation and KRAS^G12D-induced ADM, pancreatitis and PC tumorigenesis in vivo. KRAS^G12D/iASPP^Δ8/Δ8 tumours are well-differentiated classical PCs and their derivative cell lines form subcutaneous tumours in syngeneic and nude mice. Transcriptomically, either iASPP deletion or p53 mutation in the KRAS^G12D background altered the expression of an extensively overlapping gene set, comprised primarily of NF-κB and AP1-regulated inflammatory genes. All these identify iASPP as a suppressor of inflammation and a p53-independent oncosuppressor of PC tumorigenesis.

Injury primes mutation-bearing astrocytes for dedifferentiation in later life

Despite their latent neurogenic potential, most normal parenchymal astrocytes fail to dedifferentiate to neural stem cells in response to injury. In contrast, aberrant lineage plasticity is a hallmark of gliomas, and this suggests that tumor suppressors may constrain astrocyte dedifferentiation. Here, we show that p53, one of the most commonly inactivated tumor suppressors in glioma, is a gatekeeper of astrocyte fate. In the context of stab-wound injury, p53 loss destabilized the identity of astrocytes, priming them to dedifferentiate in later life. This resulted from persistent and age-exacerbated neuroinflammation at the injury site and EGFR activation in periwound astrocytes. Mechanistically, dedifferentiation was driven by the synergistic upregulation of mTOR signaling downstream of p53 loss and EGFR, which reinstates stemness programs via increased translation of neurodevelopmental transcription factors. Thus, our findings suggest that first-hit mutations remove the barriers to injury-induced dedifferentiation by sensitizing somatic cells to inflammatory signals, with implications for tumorigenesis.

Role of the Beta and Gamma Isoforms of the Adapter Protein SH2B1 in Regulating Energy Balance

Human variants of the adapter protein SH2B1 are associated with severe childhood obesity, hyperphagia, and insulin resistance-phenotypes mimicked by mice lacking Sh2b1. SH2B1β and γ isoforms are expressed ubiquitously, whereas SH2B1α and δ isoforms are expressed primarily in the brain. Restoring SH2B1β driven by the neuron-specific enolase promoter largely reverses the metabolic phenotype of Sh2b1-null mice, suggesting crucial roles for neuronal SH2B1β in energy balance control. Here we test this hypothesis by using CRISPR/Cas9 gene editing to delete the β and γ isoforms from the neurons of mice (SH2B1βγ neuron-specific knockout [NKO] mice) or throughout the body (SH2B1βγ knockout [KO] mice). While parameters of energy balance were normal in both male and female SH2B1βγ NKO mice, food intake, body weight, and adiposity were increased in male (but not female) SH2B1βγ KO mice. Analysis of long-read single-cell RNA seq data from wild-type mouse brain revealed that neurons express almost exclusively the α and δ isoforms, whereas neuroglial cells express almost exclusively the β and γ isoforms. Our work suggests that neuronal SH2B1β and γ are not primary regulators of energy balance. Rather, non-neuronal SH2B1β and γ in combination with neuronal SH2B1α and δ suffice for body weight maintenance. While SH2B1β/γ and SH2B1α/δ share some functionality, SH2B1β/γ appears to play a larger role in promoting leanness.

Animals, quality and the pursuit of relevance

In 2021, the National Institutes of Health Advisory Committee to the Director (ACD) announced recommendations to improve the reproducibility of biomedical research using animals. In response, The Jackson Laboratory faculty and institutional leaders identified key strategies to further address this important issue. Taking inspiration from the evolution of clinical trials over recent decades in response to similar challenges, we identified opportunities for improvement, including establishment of common standards, use of genetically diverse populations, requirement for robust study design with appropriate statistical methods, and improvement in public databases to facilitate meta-analyses. In this Perspective, we share our response to ACD recommendations, with a specific focus on mouse models, with the aim of promoting continued active dialogue among researchers, using any animal system, worldwide. Such discussion will help to inform the biomedical community about these recommendations and further support their much-needed implementation.

Measurement properties of the WHO Disability Assessment Schedule 2.0 for evaluating functional status after inpatient surgery

BACKGROUND

Expert recommendations propose the WHO Disability Assessment Schedule (WHODAS) 2.0 as a core outcome measure in surgical studies, yet data on its long-term measurement properties remain limited. These were evaluated in a secondary analysis of the Measurement of Exercise Tolerance before Surgery (METS) prospective cohort.

METHODS

Participants were adults (40 years of age or older) who underwent inpatient non-cardiac surgery. The 12-item WHODAS and EQ-5DTM-3L questionnaires were administered preoperatively (in person) and 1 year postoperatively (by telephone). Responsiveness was characterized using standardized response means (SRMs) and correlation coefficients between change scores. Construct validity was evaluated using correlation coefficients between 1-year scores and comparisons of WHODAS scores across clinically relevant subgroups.

RESULTS

The analysis included 546 patients. There was moderate correlation between changes in WHODAS and various EQ-5DTM subscales. The strongest correlation was between changes in WHODAS and changes in the functional domains of the EQ-5D-3L-for example, mobility (Spearman's rho 0.40, 95 per cent confidence interval [c.i.] 0.32 to 0.48) and usual activities (rho 0.45, 95 per cent c.i. 0.30 to 0.52). When compared across quartiles of EQ-5D index change, median WHODAS scores followed expected patterns of change. In subgroups with expected functional status changes, the WHODAS SRMs ranged from 'small' to 'large' in the expected directions of change. At 1 year, the WHODAS demonstrated convergence with the EQ-5D-3L functional domains, and good discrimination between patients with expected differences in functional status.

CONCLUSION

The WHODAS questionnaire has construct validity and responsiveness as a measure of functional status at 1 year after major surgery.

Influence of high cyclic ambient temperature and water drinker design on growth performance and water disappearance of growing-finishing pigs

The objective of this study was to determine effects of room temperature and drinker design on growth and water disappearance of growing-finishing pigs (26.9 ± 3.67 to 130.9 ± 5.10 kg live body weight). A split-plot design was used with a 2 × 2 factorial arrangement of treatments: Room Temperature (RT) [Thermoneutral (TN) vs. High (HI); main plot], Drinker Design (DD; Nipple vs. Cup; sub-plot). A total of 316 pigs were used, housed in 32 pens in 4 rooms (8 pens/room; 7 pens of 10 pigs and 1 pen of 9 pigs). Two rooms were on each RT treatment. Room temperature for the TN treatment was constant throughout each day but decreased from 24°C at the start to 20°C and 18°C on d 14 and 45 of the study period, respectively. For the HI treatment, a single, cyclic RT protocol was used throughout the study (30°C from 08:00 to 19:00 h and 20°C from 20:00 to 07:00 h, with 1-h transition periods). Pens had fully-slatted concrete floors and 1 feeder and drinker (either nipple or cup); floor space was 0.67 m2/pig. Pigs had ad libitum access to standard corn-soybean diets, formulated to meet or exceed NRC (2012) nutrient requirements. Water disappearance was measured using a meter fitted to the water line supplying each drinker. There were no interactions (P > 0.05) between RT and DD treatments. Drinker Design did not affect (P > 0.05) growth performance; water disappearance was 7.3% greater (P ≤ 0.05) for Nipple than Cup drinkers. Compared to the TN treatment, the HI treatment had no effect (P > 0.05) on gain:feed ratio, but resulted in lower (P ≤ 0.05) average daily gain (6.5%) and average daily feed intake (5.5%) and greater (P ≤ 0.05) average daily water disappearance (16.8%). These results suggest that both drinker design and RT can affect water disappearance, and that the high, cyclic RT regime used reduced growth performance of growing-finishing pigs. Further research is needed to determine the contribution of water intake and wastage to treatment differences in water disappearance.

PSIII-3 Changes in Sow Posture from Weaning to Estrus

Sows exhibit changes in behavior as they approach estrus that could aid in identifying the optimum time for insemination. The objective was to monitor changes in posture of sows from weaning to the first day that sows exhibited standing reflex. A cross-sectional survey was carried out using 99 multi-parous sows (in 7 groups) that were monitored over an 11–d period following weaning. At weaning, sows were moved from a farrowing to a breeding facility and were housed in individual stalls. Sows were checked daily for standing reflex from d 4 to 8 post-weaning; 97 sows exhibited standing reflex (80.4% of sows by d 6). Continuous video recordings were collected throughout the study period. Scan sampling was carried out on the videos every 5 min with the posture of each sow recorded (lying, standing, or sitting). The relative frequency of each posture was estimated as a percentage of the total number of observations within each day. Regression analyses were carried out using PROC REG of SAS to determine the rate of change in the frequency of active behavior (standing + sitting) from day of weaning to the first day of standing reflex. Over the study period, the frequency of sows lying, standing, and sitting was 76.5%, 20.0%, and 3.5%, respectively. The frequency of active behaviors increased linearly (P < 0.05) from day of weaning to day of standing reflex (Table 1); slopes ranged from 1.73 to 4.39 %/d depending on the period analyzed. However, there was considerable variation between sows with 9 showing no change in the frequency of active behavior between weaning and standing estrus. These results suggest that changes in posture could potentially be used as a predictor for the start of estrus; however, further research is needed to understand individual sow variations in these postures.

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250 Associations Between Sow and Litter Parameters and Piglet Birth Weight and the Within-Litter Coefficient of Variation of Piglet Birth Weight

The objective was to evaluate associations between sow, litter, and piglet parameters and both piglet birth weight (BW), and within-litter coefficient of variation of piglet birth weight (CV). Data (1,005 sows/litters, 12,857 piglets) were from 5 studies conducted on the same commercial farrowing facility using the same management. Independent variables included sow parity, use of farrowing induction, number of piglets born alive, litter weight, BW (for analysis of CV), and piglet sex (for analysis of BW) and birth order (for analysis of BW; on a sub-sample of 289 litters/3,643 piglets). Data were analyzed using PROC REG of SAS. Models accounted for linear, quadratic, and cubic effects of each independent variable. The BW and CV averaged 1.49 ± 0.271 kg and 19.5 ± 6.69%, respectively. All independent variables were related (P ≤ 0.05) to BW (Table 1), with litter size having the strongest relationship (R2 = 0.11), and all other variables having weak relationships (R2 ≤ 0.01). All independent variables were related (P ≤ 0.05) to CV, with the exception of farrowing induction. Litter size explained the greatest amount of variation (R2 = 0.17), followed by litter weight and average piglet birth weight (R2 = 0.10 and 0.07, respectively). Other variables each explained a relatively small proportion (R2 ≤ 0.05) of variation in CV. Multivariate models including all significant (P ≤ 0.05) variables explained 13 and 22% of the variation in BW and CV, respectively. In conclusion, the primary variable associated with both BW and CV was litter size. Increases in litter size were associated with reductions in BW and increases in CV. Other variables showed weak relationships. However, even when all of these variables were accounted for, there was a large proportion of variation in both BW and CV that was not explained.

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PSVI-2 Effect of Increasing the SID Tryptophan:Lysine Ratio and Dietary Energy Level on Growth Performance of Growing-Finishing Pigs

The objective of this study was to evaluate the effect of increasing the SID Tryptophan:Lysine ratio in growing-finishing and dietary energy level in finishing on growth performance of growing-finishing pigs (43.6 ± 0.85 kg to 131.7 ± 2.09 kg BW). A RCBD was used with a 2 × 2 factorial arrangement of treatments: A) Dietary Energy Level: Low Energy (3,294 kcal/kg ME) vs. High Energy (3,527 kcal/kg ME) and B) SID Tryptophan:Lysine Ratio: Low Try:Lys [16%] vs. High Try:Lys [21%]. Dietary Energy Level treatment was applied from 96 kg BW to end of study and SID Tryptophan:Lysine Ratio treatment was applied throughout the study period. Diets were based on corn-soybean meal and corn coproducts and formulated to meet or exceed the nutrient requirements (NRC, 2012) for each of 4 dietary phases. A total of 1,356 pigs were housed in single-sex groups of 34 pigs (10 replicates) at a floor space of 0.63 m2/pig. Pigs had ad libitum access to feed and water. Pen was the experimental unit and data were analyzed using R version 4.0.2, with the model accounting for the fixed effects of treatment, the interaction, and the random effect of replicate. There were no treatment interactions (P > 0.05). High Try:Lys compared with Low Try:Lys increased (P < 0.05) overall ADG but had no effect (P > 0.05) on ADFI or G:F (Table 1). The High Energy treatment reduced (P < 0.05) overall ADFI and increased (P < 0.05) overall G:F compared with the Low Energy treatment. In summary, pigs fed the elevated SID Tryptophan:Lysine level had increased ADG and feeding a diet with a higher dietary energy level improved feed efficiency.

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PSV-3 Changes in Sow Farrowing Performance with Parity

Sow culling decisions are based, in part, on changes in productivity with increasing age. However, there is limited published information from detailed evaluation of changes in performance with parity in contemporary commercial sows. The objective of this study was to re-evaluate relationships between sow parity and productivity measures. Data (1,005 sows/litters, 12,857 piglets) were from 5 controlled studies conducted on the same commercial farrowing facility using the same management. Sow parity (average 5.0 ± 2.79) ranged from 1 (gilts) to 14. Measurements included farrowing duration (sub-sample of 289 litters), number of piglets born alive, average and within-litter CV of piglet birth weight (BW), and sow rectal temperature at the start and end of farrowing. Data were analyzed using PROC MIXED of SAS. Models accounted for the random effect of study and the fixed effect of sow parity category (1, 2, 3 to 4, 5 to 7, and ≥ 8). Farrowing duration was similar (P > 0.05) across parity categories (Table 1). Litter size was greater (P ≤ 0.05) for parities 5 to 7 compared with parities 1 and 3 to 4, with parities 2 and ≥ 8 being intermediate and similar (P > 0.05) to all other categories. Average piglet BW was least (P ≤ 0.05) for parity 1 and greatest (P ≤ 0.05) for parity 2 and 3 to 4 sows. The CV of piglet BW generally increased (P ≤ 0.05) with parity. Rectal temperatures at the start and end of farrowing were generally greater (P ≤ 0.05) for parity 1 and 2 sows compared with the other parity categories, which were similar (P > 0.05). In conclusion, these results suggest that changes in performance with parity were relatively limited and that sows with parities that are typically considered high have relatively similar performance to those of lower parity.

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257 Effect of Drinker Design on Growth and Water Disappearance of Nursery Pigs

Changes in genetic potential and management practices may have altered the water requirements of nursery and other classes of pigs. However, there are few recent estimates of the water intake of nursery pigs or effects of factors such as drinker design on intake levels. The objective of this study was to evaluate the effect of two Drinker Design treatments (Nipple vs. Cup) on the water disappearance of nursery pigs (weaning to 6 wk post-weaning; 6.4 ± 1.07 to 22.0 ± 3.39 kg live body weight). A RCBD was used with a total of 336 pigs, housed in 16 pens of 21 pigs in 2 rooms (8 pens/room). Pens had fully slatted concrete floors; floor space was 0.32 m2/pig; there was 1 feeder and 1 drinker per pen. Pigs were fed corn-soybean based diets (meal form) formulated to meet or exceed nutrient requirements (NRC, 2012). Pigs and feeders were weighed at the start and end of the study. Water disappearance was measured using water-flow meters fitted to the pipeline supplying the drinker in each pen. Data were analyzed using the PROC MIXED procedure of SAS; models accounted for the fixed effect of Drinker Design and random effect of block. Drinker Design did not affect (P > 0.05) growth performance (Table 1). However, average daily water disappearance was 19.1% greater (P ≤ 0.05) for Nipple vs. Cup drinkers. Consequently, water:feed disappearance ratio was 15.8% greater (P ≤ 0.05) for the Nipple than the Cup treatment. In conclusion, these results suggest that water disappearance from nipple drinkers was greater than for cup drinkers. The lack of an effect of Drinker Design on pig growth performance suggests that this treatment difference was most likely due to greater water wastage for nipple drinkers rather than any effect on water intake per se.

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251 Effects of Cross-Fostering and Number of Litters Used to Create Cross-Fostered Litters on Piglet Pre-Weaning Mortality and Weaning Weight

The objective was to determine effects of cross-fostering and number of litters used to create cross-fostered litters on piglet pre-weaning mortality (PWM) and weight. The study was conducted on 2 commercial farrowing facilities using a RCBD (53 blocks; total of 265 litters/3675 piglets). Blocking factors were farrowing day, sow parity, body condition score, functional teat number, and average and CV of piglet birth weight. Treatments involved cross-fostering different percentages of the litter (0% = no cross-fostering; 50% = half cross-fostered, half from the birth sow; 100% = all piglets cross-fostered) and differing number of litters used in cross-fostering. The 5 Treatments were (% fostered/number of litters used): 1) 0%/1 litter; 2) 100%/1 litter; 3) 100%/6+ litters; 4) 50%/4+ litters; 5) 50%/2 litters. Litter sizes at cross-fostering (13 or 14 piglets) were equalized across Treatments within block. Piglets were weighed 24 h after birth (when cross-fostering was carried out) and at weaning (19.2 ± 0.97 d); all PWM was recorded. Data were analyzed using SAS, models accounted for the fixed effect of Treatment and random effects of sow, block, and farm. The 0%/1 litter and 100%/1 litter Treatments were similar (P > 0.05; Table 1) for all measurements, indicating no effect of cross-fostering per se. Litter sizes at 7 and 14 d, and weaning were lower (P ≤ 0.05) for the two 1-litter Treatments compared with the 50%/2 litters Treatment; other Treatments were intermediate. There was no effect (P > 0.05) of Treatment on piglet weight. Pre-weaning mortality was greater (P ≤ 0.05) for the two 1-litter treatments compared with the other 3 Treatments, which were similar (P > 0.05). In conclusion, cross-fostering had no effect on piglet performance, however, PWM was greater for treatments comprised of piglets from a single litter compared with those from several litters.

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248 Relationships Between Sow and Litter Parameters and Sow Rectal Temperature at the End of Farrowing

There is evidence that sow rectal temperature during farrowing may be associated with farrowing duration and difficulty, and stillbirth rates. However, factors affecting sow temperature during parturition have not been well quantified. The objective of this study was to evaluate relationships between sow and litter parameters and sow rectal temperature at the end of farrowing. Data (1005 sows/litters) were from 5 studies conducted on the same commercial farrowing facility with the same management. Independent variables included sow parity, use of farrowing induction, number of piglets born alive, litter weight, farrowing duration (on a sub-sample of 289 litters), and room temperature at the start of farrowing. Sow temperature at the end of farrowing averaged 38.5 ± 0.53°C. Data were analyzed using PROC REG of SAS. Models accounted for the linear, quadratic, and cubic effects of continuous independent variables, and/or the categorical effect of farrowing induction. Sow rectal temperature at the start of farrowing had a positive relationship with sow temperature at the end of farrowing and the greatest R2 value (0.33; Table 1). Individually, sow parity, farrowing duration, and induction were related (P ≤ 0.05) to sow rectal temperature at the end of farrowing. However, these factors explained a small proportion of the variation (R2 ≤ 0.05) in sow temperature. For the multivariate model, only room temperature and sow rectal temperature at the start of farrowing were related (P ≤ 0.05) to temperature at the end of farrowing, explaining 34% of the variation. In conclusion, these results suggest that sow temperature at the start of farrowing had the greatest influence on temperature at the end and that other factors (sow parity, farrowing duration, farrowing induction, and room temperature) were relatively unimportant.

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249 Relationships Between Sow, Litter, and Piglet Parameters and the Rectal Temperature of Piglets at Birth and 30 Min After Birth

The objective was to evaluate relationships between sow, litter, and piglet parameters and piglet rectal temperature at birth and 30 min after birth. Data (460 sows/litters; 1,240 piglets) were from 5 studies conducted on the same commercial farrowing facility with the same management. Sow variables included parity and rectal temperature at start of farrowing, and use of farrowing induction. Piglet variables included birth weight, rectal temperature at 0 and 30 min after birth, birth interval (time from the birth of the previous piglet), birth order, and sex. Other variables included room temperature at start of farrowing and number of piglets born alive. Piglets were only handled to collect measurements; no interventions were used. Data were analyzed using PROC REG of SAS. Models accounted for the linear, quadratic, and cubic effects of each independent variable. Mean piglet temperature at birth and 30 min was 38.8 ± 0.55°C and 35.7 ± 1.35°C, respectively. For piglet birth temperature, all variables were related except farrowing induction and piglet sex (Table 1). The relationship with sow temperature at start of farrowing was positive and had the greatest R2 value (0.18). For piglet 30 min temperature, all variables were related (P ≤ 0.05) except sow parity, farrowing induction, and piglet sex (Table 1). The relationship with piglet birth weight was positive and had the greatest R2 value (0.31). Multivariate models including all significant (P ≤ 0.05) terms explained 35 and 50% of the variation in piglet birth and 30 min temperature, respectively. In conclusion, the primary factor affecting piglet birth and 30 min temperature was sow temperature and piglet birth weight, respectively. However, even when combining all of the factors, a large proportion of the variation in piglet temperature at both times remained unexplained.

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4 Variation in Sow Body Temperature Following Weaning

There is limited data available on variation in sow temperature following weaning. The objective of this study was to determine variation (diurnal and with day post-weaning) in rectal (RT) and vulva surface (VT) temperature following weaning. A cross-sectional survey was carried out using 114 multi-parous sows weaned in 7 groups between September and December. Sows were housed in individual stalls and were checked daily for standing reflex from d 4 to 8 post-weaning. Sow RT (measured with a standard thermometer) and VT (measured with an infrared thermal camera) were measured daily [at 06:15 (feeding time), 07:00, 07:30 (heat checking time), 09:00, 11:00, 13:00, 15:00, 17:00, 19:00, 21:00, and 23:00]. A repeated-measures analysis was carried out using PROC MIXED of SAS; models included the fixed effect of either study day or measurement time, and random effect of group. The number of sows exhibiting standing reflex on d 4, 5, 6, 7, and 8 post-weaning was 1, 45, 45, 19, 1, respectively; 3 sows did not exhibit standing reflex. Average VT and RT over the study period were 30.8 ± 3.23 and 38.2 ± 0.60°C, respectively; the correlation between these measurements was 0.08 (P < 0.05). There was considerable day-to-day variation in average VT (range between day: 29.5 to 32.6°C) and to a lesser extent RT (range: 37.7 to 38.5°C). The VT was higher (P < 0.05) on d 3 to 5 post-weaning compared with other days. Also, VT was higher (P < 0.05) between 06:15 and 07:30 than at the other measurement times. There was no clear pattern for either day-to-day or diurnal variation in RT. In conclusion, this study described between-sow variation in RT and VT following weaning. Further research is needed to determine if any of this variation in temperature is associated with the onset of estrus.

3 Effect of Litter Size and Provision of Supplementary Liquid Milk Replacer During Lactation on Piglet Pre-Weaning Performance

Recent increases in litter size in commercial sows have been accompanied by higher pre-weaning mortality (PWM) and lower weaning weights. The objective was to determine effects of litter size and feeding liquid milk replacer during lactation (using an automated feeder) on piglet performance. A split-plot design was used with a 2x2 factorial arrangement of treatments: Milk Replacer (MR; main plot; Unsupplemented vs. Supplemented); Litter Size [LS; sub-plot; Low (2 piglets less than functional teat number) vs. High (2 piglets greater than functional teat number)]. Cross-fostering was carried out at 24 h after birth to create treatment litters with similar gender ratio, proportion of cross-fostered piglets, and average and CV of birth weight. Milk replacer was available from 24 h after birth to weaning. Piglets were weighed on d 1 and 20 (weaning) after birth; all PWM was recorded. Growth data were analyzed using PROC MIXED of SAS; PWM data were analyzed using PROC GLIMMIX. Models accounted for fixed effects of MR, LS, the interaction, and random effects of replicate and replicate by MR interaction. There were no MR by LS interactions (P > 0.05) for any measurement. Supplemented compared with Unsupplemented litters had similar (P > 0.05) litter size at weaning and PWM, but greater (P < 0.05) average piglet and total litter weaning weight (Table 1). The High LS treatment had greater (P < 0.05) litter size and total litter weight at d 1 and weaning, but higher (P < 0.05) PWM and lower (P < 0.05) average piglet weaning weight. In conclusion, supplementing piglets with liquid milk replacer increased weaning weight with no effect on PWM, and increasing litter size above sow teat number had negative effects on both PWM and piglet weaning weight.

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The nucleolar δ isoform of adapter protein SH2B1 enhances morphological complexity and function of cultured neurons

The adapter protein SH2B1 is recruited to neurotrophin receptors, including TrkB (also known as NTRK2), the receptor for brain-derived neurotrophic factor (BDNF). Herein, we demonstrate that the four alternatively spliced isoforms of SH2B1 (SH2B1α-SH2B1δ) are important determinants of neuronal architecture and neurotrophin-induced gene expression. Primary hippocampal neurons from Sh2b1-/- [knockout (KO)] mice exhibit decreased neurite complexity and length, and BDNF-induced expression of the synapse-related immediate early genes Egr1 and Arc. Reintroduction of each SH2B1 isoform into KO neurons increases neurite complexity; the brain-specific δ isoform also increases total neurite length. Human obesity-associated variants, when expressed in SH2B1δ, alter neurite complexity, suggesting that a decrease or increase in neurite branching may have deleterious effects that contribute to the severe childhood obesity and neurobehavioral abnormalities associated with these variants. Surprisingly, in contrast to SH2B1α, SH2B1β and SH2B1γ, which localize primarily in the cytoplasm and plasma membrane, SH2B1δ resides primarily in nucleoli. Some SH2B1δ is also present in the plasma membrane and nucleus. Nucleolar localization, driven by two highly basic regions unique to SH2B1δ, is required for SH2B1δ to maximally increase neurite complexity and BDNF-induced expression of Egr1, Arc and FosL1.

A Compound Heterozygous Mutation in Calpain 1 Identifies a New Genetic Cause for Spinal Muscular Atrophy Type 4 (SMA4)

Spinal Muscular Atrophy (SMA) is a heterogeneous group of neuromuscular diseases characterized by degeneration of anterior horn cells of the spinal cord, leading to muscular atrophy and weakness. Although the major cause of SMA is autosomal recessive exon deletions or loss-of-function mutations of survival motor neuron 1 (SMN1) gene, next generation sequencing technologies are increasing the genetic heterogeneity of SMA. SMA type 4 (SMA4) is an adult onset, less severe form of SMA for which genetic and pathogenic causes remain elusive.Whole exome sequencing in a 30-year-old brother and sister with SMA4 identified a compound heterozygous mutation (p. G492R/p. F610C) in calpain-1 (CAPN1). Mutations in CAPN1 have been previously associated with cerebellar ataxia and hereditary spastic paraplegia. Using skin fibroblasts from a patient bearing the p. G492R/p. F610C mutation, we demonstrate reduced levels of CAPN1 protein and protease activity. Functional characterization of the SMA4 fibroblasts revealed no changes in SMN protein levels and subcellular distribution. Additional cellular pathways associated with SMA remain unaffected in the patient fibroblasts, highlighting the tissue specificity of CAPN1 dysfunction in SMA4 pathophysiology. This study provides genetic and functional evidence of CAPN1 as a novel gene for the SMA4 phenotype and expands the phenotype of CAPN1 mutation disorders.

Effect of drinker type on water disappearance of nursery pigs

This study was conducted to evaluate the water disappearance of nursery pigs (from weaning to 6 wk post-weaning; 6.4 ± 1.07 to 22.0 ± 3.39 kg live body weight) using a randomized complete block design to compare two Drinker Type treatments: Nipple vs. Cup. A total of 336 pigs housed in 16 pens with 21 pigs per pen in 2 rooms (8 pens per room) were used. Pens had fully-slatted concrete floors; floor space was 0.32 m2/pig and there was one feeder and one drinker per pen. Pigs were fed corn-soybean-based diets formulated to meet or exceed nutrient requirements. Pigs and feeders were weighed at the start and end of the study. Water disappearance was measured using a water-flow meter fitted to the water pipeline supplying the drinker in each pen. For the overall study period, Drinker Type did not affect (P > 0.05) growth performance; however, average daily water disappearance was greater (P < 0.05) for Nipple than Cup drinkers (2.74 and 2.25 liters/d, respectively; SEM = 0.139). Water to feed disappearance ratio was greater (P < 0.05) for the Nipple than the Cup treatment (5.23 vs. 4.22 liters:kg, respectively; SEM = 0.263). These results suggest that water disappearance from nipple drinkers was greater than for cup drinkers. The lack of an effect of Drinker Type treatment on pig growth performance suggests that the treatment difference for water disappearance was most likely due to greater water wastage for the nipple drinkers rather than any effect on water intake per se.

Effect of rearing cross-fostered piglets in litters of either uniform or mixed birth weights on preweaning growth and mortality

Cross-fostering is a practice commonly used in the swine industry to equalize litter sizes, however, there is limited understanding of the optimum cross-fostering methods that will maximize piglet preweaning growth and survival. This study evaluated the effects of within-litter variation in birth weight after cross-fostering on piglet preweaning mortality (PWM) and weaning weight (WW) using litters of 15 piglets. A hierarchical incomplete block design was used (blocking factors: day of farrowing and sow parity, body condition score, and number of functional teats) with a 3 × 2 factorial arrangement of treatments: 1) Birth Weight Category (BWC): Light (<1.0 kg), Medium (1.0 to 1.5 kg), or Heavy (1.5 to 2.0 kg); 2) Litter Composition: UNIFORM (all 15 piglets in each litter of the same BWC), or MIXED (five piglets in each litter from each BWC, i.e., five Light, five Medium, and five Heavy piglets). At 24 h after birth, piglets were weighed and randomly allotted to litter composition treatments from within BWC. The experimental unit was five piglets of the same BWC; there were three experimental units within each Litter Composition treatment litter. There were 17 blocks, each of six litters (one UNIFORM litter of each BWC; three MIXED litters) and 51 replicates (three replicates per block of six litters) for a total of 102 cross-fostered litters and 1,530 piglets. Piglets were weaned at 19.7 ± 0.46 d of age; WW and PWM were measured. PROC GLIMMIX and MIXED of SAS were used to analyze PWM and WW, respectively. Models included BWC, Litter Composition, the interaction, and replicate within the block. There were BWC by Litter Composition treatment interactions (P ≤ 0.05) for PWM and WW. Preweaning mortality was greater (P ≤ 0.05) for Light piglets in MIXED than UNIFORM litters. In contrast, for Heavy piglets, PWM was greater (P ≤ 0.05) and WW was lower (P ≤ 0.05) in UNIFORM than MIXED litters. Medium piglets had similar (P > 0.05) PWM and WW in UNIFORM and MIXED litters. The results of this study, which involved large litter sizes typical of current commercial production, suggested that for piglet survival to weaning, using cross-fostering to form litters of piglets of similar birth weight was beneficial for light piglets, detrimental for heavy piglets, and neutral for medium piglets.

Effect of drying and warming piglets at birth on preweaning mortality

Piglets are susceptible to hypothermia early after birth, which is a major predisposing factor for preweaning mortality (PWM). Drying and warming piglets at birth has been shown to reduce early postnatal temperature decline. This study evaluated the effect of drying and warming piglets at birth on PWM and weaning weight (WW) under commercial conditions. A completely randomized design was used with 802 sows/litters (10,327 piglets); sows/litters were randomly allotted at start of farrowing to one of two Intervention Treatments (applied at birth): Control (no drying or warming); Drying+Warming (dried with a cellulose-based desiccant and placed in a box under a heat lamp for 30 min). Piglets were weighed at birth and weaning; PWM was recorded. Rectal temperature was measured at 0 and 30 min after birth on all piglets in a subsample of 10% of litters. The effect of farrowing pen temperature (FPT) on WW and PWM was evaluated by comparing litters born under COOL (<25°C) to those born under WARM (≥25°C) FPT. The effect of birth weight on WW and PWM was evaluated by comparing three birth weight categories (BWC; Light: <1.0 kg, Medium: 1.0 to 1.5 kg, or Heavy: >1.5 kg). PROC GLIMMIX and MIXED of SAS were used to analyze mortality and other data, respectively. Litter was the experimental unit; piglet was a subsample of litter. The model included fixed effects of Intervention Treatment, and FPT or BWC as appropriate, the interaction, and the random effects of litter. Piglet rectal temperature at 30 min after birth was greater (P ≤ 0.05) for the Drying+Warming than the Control treatment (+2.33°C). Overall, there was no effect (P > 0.05) of Intervention Treatment on PWM or WW, and there were no Intervention Treatment by BWC interactions (P > 0.05) for these measurements. There was an Intervention Treatment by FPT interaction (P ≤ 0.05) for PWM. Drying and warming piglets reduced (P ≤ 0.05) PWM under COOL (by 2.4 percentage units) but not WARM FPT. In addition, WW were lower (P ≤ 0.05) under WARM (by 0.79 kg) than COOL FPT; however, there was no interaction (P > 0.05) with Intervention Treatment. In conclusion, this study suggests that drying and warming piglets at birth increases rectal temperature and may reduce PWM under cooler conditions, which are typically experienced in temperate climates during the majority of the year.

Effect of rearing cross-fostered piglets in litters of differing size relative to sow functional teat number on preweaning growth and mortality

Litter sizes of commercial sows have increased considerably over recent decades, and often exceed the number of functional teats on the sow. The objective of this study was to evaluate the effect of litter size after cross-fostering relative to sow functional teat number on piglet preweaning growth and mortality. A total of 39 litters (561 piglets) were used in a randomized complete block design; blocking factors were farrowing day and sow parity, body condition score, and functional teat number. Three Litter Size treatments were compared (relative to sow functional teat number): Decreased (two piglets less); Control (same number of piglets); Increased (two piglets more). Piglets were randomly allotted to treatment at 24 h after birth to form litters of the appropriate size, with similar mean and CV of birth weight within block. Weaning weights (WW) were collected at 19.5 ± 0.50 d of age; preweaning mortality (PWM) was recorded. Litter sizes were between 11 and 17 piglets, depending on block and treatment. The Decreased treatment had lower (P ≤ 0.05) PWM than the Increased (7.7% and 17.9%, respectively); the Control was intermediate (11.5%) and not different (P > 0.05) from the other treatments. The rate of decline in litter size from birth to weaning was greater (P ≤ 0.05) for the Increased than the Decreased treatment (-0.16 vs. -0.05 piglets per day), with the Control (-0.09 piglets per day) being intermediate and different (P ≤ 0.05) to the other two treatments. Litter sizes at weaning were greater (P ≤ 0.05) for the Increased than the Decreased treatment (13.3 and 11.3, respectively); the Control treatment was intermediate (12.6) and not different (P > 0.05) to the other treatments. The log odds of PWM increased with the decreasing birth weight, at a similar rate (P > 0.05) for all Litter Size treatments. However, the intercept was greater (P ≤ 0.05) for the Increased compared with the Decreased treatment; the Control was intermediate and different (P > 0.05) to the other two treatments. Mean WW tended (P = 0.07) to be greater for the Decreased (6.17 kg) compared to the Control and Increased treatments (5.86 and 5.84 kg, respectively). In conclusion, increasing litter size after cross-fostering relative to the number of functional teats of the sow increased piglet PWM, and tended to decrease WW.

Effect of farrowing pen size on pre-weaning performance of piglets

Litter sizes in commercial pig production have increased substantially over recent years; however, farrowing pen sizes have generally not changed over the same time period. The objective of this study was to evaluate the effect of farrowing pen size on piglet pre-weaning growth and mortality. Differences in pen size were created by varying the width of pens of the same length, increasing the creep area available to the piglets. The study used a total of 1,786 litters in a randomized complete block design to compare two farrowing pen size treatments (FPS): Standard (pen width 1.52 m) and Increased (pen width 1.68 m). Litter sizes were equalized across treatments (12.9 ± 1.95 piglets) at 24 h after birth using cross-fostering. Litter weights were collected at birth and weaning (21.3 ± 2.08 d); pre-weaning mortality was recorded. The experimental unit was the litter; models for statistical analysis included FPS and replicate. Farrowing pen size had no effect (P > 0.05) on litter size at birth (12.8 and 13.0 for the Standard and Increased FPS, respectively), after cross-fostering (12.9 for both treatments), or at weaning (11.2 and 11.3, respectively). There was no effect (P > 0.05) of FPS on total litter or average piglet weight at birth, after cross-fostering, and at weaning. These results suggest no benefit in piglet performance from increasing the width of farrowing pens. As litter sizes continue to increase in commercial production, further research is warranted to re-evaluate the impact of farrowing pen size on pre-weaning mortality.

Effect of within-litter birth weight variation after cross-fostering on piglet preweaning growth and mortality

Cross-fostering is commonly used in commercial swine production to equalize litter sizes and/or adjust piglet birth weights within litters. However, there is limited published information on optimum cross-fostering procedures. This study evaluated the effects of within-litter birth weight variation after cross-fostering (using litters of 14 piglets) on piglet preweaning mortality (PWM) and weaning weight (WW). An RCBD was used (blocking factors were day of farrowing and sow parity, body condition score, and functional teat number) with an incomplete factorial arrangement of the following two treatments: 1) birth weight category (BWC): light (<1.0 kg), medium (1.0 to 1.5 kg), or heavy (1.5 to 2.0 kg); 2) litter composition: uniform, all piglets in the litter of the same BWC [uniform light (14 light piglets); uniform medium (14 medium piglets); uniform heavy (14 heavy piglets)]; mixed, piglets in the litter of two or more BWC [L+M (seven light and seven medium piglets); M+H (seven medium and seven heavy piglets); L+M+H (three light, six medium, and five heavy piglets)]. Piglets were weighed at 24 h after birth and randomly allotted to litter composition treatment from within BWC; all piglets were cross-fostered. There were 47 blocks of six litters (total 282 litters and 3,948 piglets). Weaning weights were collected at 18.7 ± 0.64 d of age; all PWM was recorded. Individual piglet WW and PWM data were analyzed using PROC MIXED and PROC GLIMMIX of SAS, respectively; models included fixed effects of BWC, litter composition, and the interaction, and random effects of sow within the block. There was litter composition by BWC interactions (P ≤ 0.05) for WW and PWM. Within each BWC, WW generally increased and PWM generally decreased as littermate weight decreased. For example, WW was greatest (P ≤ 0.05) for light piglets in uniform light litters, for medium piglets in L+M litters, and for heavy piglets in L+M+H litters. Preweaning mortality was lowest (P ≤ 0.05) for medium piglets in L+M litters, and for heavy piglets in L+M+H litters; however, litter composition had no effect (P > 0.05) on PWM of light piglets. In conclusion, increasing the average birth weight of littermates after cross-fostering generally decreased WW and increased PWM for piglets of all birth weight categories. This implies that the optimum approach to cross-fostering that maximizes piglet preweaning growth and survival is likely to vary depending on the birth weight distribution of the population.

Effects of drying and providing supplemental oxygen to piglets at birth on rectal temperature over the first 24 h after birth

Neonatal piglets can experience both a decrease in body temperature and hypoxia, increasing risks for pre-weaning mortality. This research evaluated the effects of drying and providing supplemental oxygen to newborn piglets on rectal temperature (RT) over the first 24 h after birth. The study used a CRD with three Intervention Treatments (IT; applied at birth): Control (no intervention), Drying (dried using a desiccant), Oxygen [dried using a desiccant and placed in a chamber (at 40% oxygen concentration) for 20 min]. A total of 42 litters (485 piglets) were randomly allotted to treatments at the start of farrowing. At birth, each piglet was given a numbered ear tag, weighed, and the treatment was applied; RT was measured at 0, 20, 30, 45, 60, 120, and 1440 min after birth. Blood was collected from one piglet from each birth weight quartile within each litter at 24 h after birth to measure plasma immunocrit concentration. There was no effect (P > 0.05) of IT on piglet RT at 0 or 1440 min after birth. Between 20 and 60 min after birth, piglet RT was lower (P ≤ 0.05) for the Control than the Drying treatment, with the Oxygen treatment being intermediate and different (P ≤ 0.05) from the other two IT. The effect of piglet birth weight on responses to IT were evaluated by classifying piglets into Birth Weight Categories (BWC): Light (<1.0 kg), Medium (1.0 to 1.5 kg), or Heavy (>1.5 kg). There were IT by BWC interactions (P ≤ 0.05) for piglet RT at all measurement times between 20 and 120 min after birth. Relative to the Control, the effects of the Drying and Oxygen treatments on RT were greater (P ≤ 0.05) for Light than heavier piglets. Plasma immunocrit concentrations tended (P = 0.07) to be greater for piglets on the Control treatment compared to the other two IT and were lower (P ≤ 0.05) for Light than Heavy piglets, with Medium piglets being intermediate and different (P ≤ 0.05) to the other BWC. In conclusion, drying piglets at birth reduced the extent and duration of RT decline in piglets in the early postnatal period compared to undried piglets, especially for those of low birth weight. However, the combination of drying and placing piglets in an oxygen-rich environment provided no additional benefit over drying alone.

87 Effect of Number of Source Litters Used to Create Cross-fostered Litters on Piglet Pre-weaning Mortality and Weaning Weight

Sow litter sizes have increased over recent decades, increasing the need for cross-fostering. The objective of this study was to determine the effect of the number of source litters used to create cross-fostered litters on piglet pre-weaning mortality (PWM) and weaning weight. A RCBD was used with 26 blocks of 5 litters (total 130 litters/1820 piglets), all litters consisted of 14 piglets. Blocking factors were farrowing day, sow parity, body condition score, and functional teat number, and the average and CV of piglet birth weight. Five cross-fostering treatments were compared: 0%, 1 source (all piglets remaining on the birth sow); 100%, 1 source (all piglets moved from birth to a different sow); 100%, 6+ sources (piglets from ≥ 6 birth sows used to form a litter on a different sow); 50%, 2 sources (7 piglets remaining with birth sow, 7 from one other sow); 50%, 4+ sources (7 piglets remaining with the birth sow, 7 from ≥ 3 other sows). The single-source litters were selected from those with &gt; 14 piglets at birth, with excess piglets removed. For other treatments, piglets were selected to meet blocking factors. Piglets were weighed 24 h after birth and at weaning (19.5 ± 0.50 d); all PWM was recorded. Weight data were analyzed using PROC MIXED of SAS; PWM data were analyzed using PROC GLIMMIX of SAS. Models included Treatment and sow within block. There was no effect (P &gt; 0.05) of treatment on weaning weights. Pre-weaning mortality was greater (P &lt; 0.05) for the 0%, 1 source compared to the 50%, 2 source treatment, with the others being intermediate and generally not statistically different (Table 1). In conclusion, cross-fostering and/or mixing litters had no effect on weaning weights, but pre-weaning mortality was highest for the non-fostered treatment.

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PSIII-3 Effect of Type of Desiccant Used to Dry Piglets at Birth on Postnatal Changes in Rectal Temperature

All piglets experience hypothermia immediately after birth, which can be a predisposing factor for pre-weaning mortality. Drying piglets at birth with a desiccant reduces the extent and duration of postnatal temperature decline. This study compared the effectiveness of different types of commercially-available desiccant products using a CRD with four treatments (applied at birth): Control (piglets not dried) and 3 Desiccant Product treatments [dried with a Mineral-based, Cellulose-based, or Mixed (mineral and cellulose-based) desiccant]. Sows (40) and litters (546 piglets) were randomly allotted to a treatment at the birth of the first piglet. Sows were housed in individual farrowing crates within pens; a heat lamp was suspended over one side of each pen. Room temperature was set at 22.8°C throughout farrowing. Piglets were weighed at birth, those on the Desiccant Product treatments were coated with desiccant until completely dry, and then returned to the pen. Piglet rectal temperatures were measured at 0, 15, 30, 45, 60 and 120 min after birth. Data were analyzed using PROC MIXED of SAS (SAS Inst. Inc., Cary, NC). The model included the fixed effects of treatment, measurement time (repeated measure), and the interaction. There was no effect (P &gt; 0.05) of treatment on rectal temperatures at birth. At all other measurement times, piglets on the Control treatment had lower (P &lt; 0.05) rectal temperatures than those on the 3 Desiccant Product treatments, which had similar (P &gt; 0.05) rectal temperatures. These results suggest that the 3 commercial desiccant products evaluated were equally effective at minimizing the extent and duration of piglet rectal temperature decline in the early postnatal period.

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PSIII-2 Effect of Piglet Characteristics on Blood Glucose Levels at Birth

Blood glucose levels in piglets at birth are potentially associated with survival, however, there has been limited research to quantify these and to establish any associations with piglet characteristics. This study, which evaluated the effects of a number of piglet characteristics on blood glucose levels at birth, was conducted as a cross-sectional survey involving 32 litters. Litter was the experimental unit; piglet was a sub-sample of litter. At birth, piglets were weighed and assigned a vitality score [1 = high vitality; 2 = low vitality (limited mobility and/or respiration)]. Piglets were then dried with a cellulose-based desiccant, and blood samples were collected from half of the piglets in each litter with a vitality score of 1 (n = 226) and all piglets with a vitality score of 2 (n = 7). Samples (1.2 μL) were collected from the vena subcutanea abdominis; blood glucose was measured using a glucometer (Accuchek Aviva; Roche Diabetes Care, Inc., Indianapolis, IN). Effects of piglet characteristics and relationships with blood glucose levels were analyzed using PROC MIXED, PROC GLIMMIX, and PROC REG of SAS, as appropriate. There were no effects (P &gt; 0.05) of piglet birth weight or gender on blood glucose levels. Piglets with a vitality score of 2 had higher (P &lt; 0.05) blood glucose levels than those with a score of 1. Blood glucose levels increased linearly (P &lt; 0.05) with birth order (0.8 mg/dL for each piglet increase). In conclusion, blood glucose levels at birth were higher for piglets with low compared to high vitality and for those born later in the birth order. Further research is needed to establish relationships between blood glucose levels in piglets at birth and subsequent survival.

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92 Effect of Rearing Cross-fostered Piglets in Litters of Differing Within-litter Birth Weight Variation on Pre-weaning Growth and Mortality

Cross-fostering of piglets is a common commercial practice, however, there is limited information on optimum methods. The objective of this study was to evaluate the effects of within-litter birth weight variation after cross-fostering on piglet pre-weaning mortality (PWM) and growth. A RCBD was used with 47 blocks of 6 litters (total 282 litters/3,948 piglets); blocking factors were farrowing day, sow parity, body condition score, and functional teat number. Piglets were allotted at 24 h after birth according to Birth Weight Category (BWC) [L (&lt; 1.0 kg), M (1.0 to 1.5 kg), or H (1.5 to 2.0 kg)] to 6 Litter Composition (LC) treatments with 14 piglets/litter: Uniform (14 L, M or H); Mixed L+M (7 L, 7 M); Mixed M+H (7 M, 7 H); Mixed L+M+H (3 L, 6 M, 5 H). Piglets were weaned at 18.7 ± 0.64 d and PWM was recorded. Piglet birth and weaning weights were analyzed using PROC MIXED of SAS; PWM were analyzed using PROC GLIMMIX of SAS; models included BWC, LC, the interaction, and sow within block. There were LC by BWC interactions (P &lt; 0.05) for PWM and weaning weights. For L piglets, there was no effect (P &gt; 0.05) of LC on PWM (22.8, 26.7, and 28.4% for Uniform, Mixed L+M, and Mixed L+M+H treatments, respectively). For H piglets, PWM was lower (P &lt; 0.05) in Mixed L+M+H compared to Uniform or Mixed M+H litters (1.7, 9.6, and 5.8%, respectively). For M piglets, PWM was lower (P &lt; 0.05) in Mixed L+M than Uniform or Mixed M+H litters (7.1, 12.2, and 14.6%, respectively); Mixed L+M+H were intermediate (10.0%; P &gt; 0.05). Weaning weights generally followed a similar but opposite pattern for all BWC. In conclusion, increasing the average weight of littermates generally decreased weaning weights and increased PWM within each BWC.

PSVI-15 Effects of Dietary SID Lysine Restriction in the Growing Period and Number of Dietary Phases on Growth Performance of Growing-finishing Pigs

This study evaluated the effects of dietary SID lysine restriction in the growing period and number of dietary phases in the growing-finishing (GF) period on growth performance of GF pigs (32.7 ± 9.43 kg to 115.5 ± 8.18 kg BW). A RCBD (block = gender and start day) was used with a 3 × 2 factorial arrangement of treatments: 1) Dietary SID Lysine Level {Control [NRC (2012) recommendation]; Moderate Restriction [0.15% lower than Control]; Aggressive Restriction [0.30% lower than Control]} and 2) Number of Dietary Phases in GF (4 vs. 2). Lysine level treatments were applied from 32 to 64 kg BW. Diets were based on corn-soybean meal and corn coproducts, formulated to be isocaloric, and to meet or exceed recommendations of NRC (2012) for each phase, with the exception of SID lysine levels which were according to treatment. A total of 4,488 pigs were housed in single-sex groups of 34 pigs (22 replicates) with floor space of 0.63 m2/ pig. Pigs had ad libitum access to feed and water throughout and were weighed at start and end of the study; feeder additions were recorded. Pen was the experimental unit and data were analyzed using R version 3.6.2. The model accounted for the fixed effect of treatments, the interaction, and random effect of block. There were no treatment interactions (P &gt; 0.05) and no effect (P &gt; 0.05) of Number of Dietary Phases on overall growth performance. Decreasing dietary SID lysine linearly reduced (P &lt; 0.05) overall ADG and ADFI with no effect (P &gt; 0.05) on G:F. Restricting dietary SID lysine level to the extent used in this study reduced overall growth rate with no impact on feed efficiency.

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147 Effect of Within-pen Variation in Weaning Weight on the Growth Performance of Nursery Pigs

This study evaluated the effect of housing newly-weaned pigs in uniform versus mixed weight groups on nursery growth performance (5.9 ± 1.1 to 26.2 ± 2.9 kg BW). Pigs were assigned to a weaning weight (WW) quartile: Q1 (light; 4.2 ± 0.1 kg), Q2 (medium-light; 5.5 ± 0.1 kg), Q3 (medium-heavy; 6.3 ± 0.2 kg), and Q4 (heavy; 7.5 ± 0.1 kg). A RCBD was used (blocking factor = start date) with 5 treatments: Control (equal number of pigs from each quartile); Uniform Q1 (all pigs from Q1); Uniform Q2 (all pigs from Q2); Uniform Q3 (all pigs from Q3); Uniform Q4 (all pigs from Q4). There were 16 replicates and 3,503 pigs, with mixed-gender pens of 44. Pen was the experimental unit; data were analyzed using PROC MIXED of SAS (fixed effect = treatment; random effect = replicate). Overall ADG and ADFI increased (P &lt; 0.05) according to WW quartile for the Uniform treatments, with the Control being intermediate. There were no differences (P &gt; 0.05) between treatments for Overall G:F. A contrast statement was used to compare Control to the mean of all 4 Uniform treatments. Compared to Control, the mean of the 4 Uniform treatments had similar (P &gt; 0.05) overall ADG (0.44 vs. 0.44 kg, respectively) and ADFI (0.72 vs. 0.68 kg, respectively), but greater (P &lt; 0.05) overall G:F (0.637 vs. 0.611, respectively). Comparison of pigs from each quartile within Control pens with the respective quartile in Uniform pens suggested no effect (P &gt; 0.05) of weight quartile on ADG (respective means for Control vs Uniform: Q1 0.34 vs. 0.36 kg; Q2 0.39 vs. 0.40 kg; Q3 0.42 vs. 0.42 kg; Q4 0.47 vs. 0.45 kg). These results suggest that penning nursery pigs in uniform versus mixed weight groups had limited effect on growth performance.

178 Relationships Between Sow Blood Glucose Levels on Day of Farrowing and Sow and Litter Parameters

Low blood glucose levels at the start of farrowing have been associated with increased farrowing duration and stillbirth rate. This study evaluated changes in sow blood glucose (BG) on the day of farrowing and investigated relationships between sow and litter parameters and BG. The study was carried out over 12 h from 0600h (time of last feeding) on the day sows were induced to farrow (d 115 of gestation) as a cross-sectional survey using 42 sows/gilts of which 32 farrowed. Blood samples (1.2 μL) were collected from an ear vein of each sow every 2 h from 0600 h; glucose was measured using a glucometer (Accuchek Aviva; Roche Diabetes Care, Inc., Indianapolis, IN). Sow parameters recorded included parity, body condition score (BCS: 1 = extremely thin to 5 = extremely fat), number of piglets born, total litter birth weight, and farrowing duration. Linear relationships between sow parameters and BG were developed using PROC REG of SAS. Sows that farrowed had similar (P &gt; 0.05) BG to those that did not (84.4 vs. 86.8 mg/dL; SEM 1.76). Regression relationships between sow parameters and BG were generally weak (adjusted R2 ≤ 0.20). There was no effect (P &gt; 0.05) of time after feeding, time after start of farrowing, or time interval between piglet births on BG. Average BG levels increased linearly (P &lt; 0.05) with sow BCS (7.6 mg/dL/BCS; SE 2.63) but decreased linearly (P &lt; 0.05) with sow parity (-2.5 mg/dL/litter; SE 0.96), litter size (-0.8 mg/dL/piglet; SE 0.28), litter weight (-0.06 mg/dL/kg; SE 0.26), and farrowing duration (-1.8 mg/dL/h; SE 0.82). In contrast to previous research, changes in BG from last feed to start of farrowing (which ranged from 0 to 9 h) and relationship with other sow and litter parameters were relatively limited.

PSIII-1 Effect of Rearing Cross-fostered Piglets in Litters of Differing Size Relative to Sow Functional Teat Number on Pre-weaning Growth and Mortality

Litter sizes of commercial sows have increased recently, often resulting in the number of piglets exceeding the sow functional teat number. The objective of this study was to determine the effects of litter size after cross-fostering on piglet pre-weaning mortality (PWM) and growth. A RCBD was used with 13 blocks of 3 litters (total 39 litters/561 piglets); blocking factors were farrowing day, sow parity, body condition score, and functional teat number. Three Litter Size treatments (LS) relative to sow functional teat number were compared: Under (2 piglets below); Equal (same number of piglets); Over (2 piglets above). Piglets were weighed 24 h after birth and allotted to LS to create litters with similar gender ratio and average and CV of birth weight. Weaning was at 19.5 ± 0.50 d, weights and PWM were recorded. Piglet weight data were analyzed using PROC MIXED of SAS; PWM data were analyzed using PROC GLIMMIX of SAS. Models included LS and sow within block. Litter sizes averaged 12.1, 14.1, and 16.1 for the Under, Equal, and Over treatments, respectively (P ≤ 0.05). The Under treatment tended (P = 0.07) to have greater weaning weights compared to the Equal and Over treatments (Table 1). The Under treatment had lower (P ≤ 0.05) PWM than the Over treatment, with the Equal treatment being intermediate and not different to the other 2 (P &gt; 0.05; Table 1). In conclusion, reducing litter size after cross-fostering to two piglets below the number of functional teats of the sow decreased PWM and tended to increase weaning weights.

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Global phosphoproteomics reveals DYRK1A regulates CDK1 activity in glioblastoma cells

Both tumour suppressive and oncogenic functions have been reported for dual-specificity tyrosine phosphorylation-regulated kinase 1A (DYRK1A). Herein, we performed a detailed investigation to delineate the role of DYRK1A in glioblastoma. Our phosphoproteomic and mechanistic studies show that DYRK1A induces degradation of cyclin B by phosphorylating CDC23, which is necessary for the function of the anaphase-promoting complex, a ubiquitin ligase that degrades mitotic proteins. DYRK1A inhibition leads to the accumulation of cyclin B and activation of CDK1. Importantly, we established that the phenotypic response of glioblastoma cells to DYRK1A inhibition depends on both retinoblastoma (RB) expression and the degree of residual DYRK1A activity. Moderate DYRK1A inhibition leads to moderate cyclin B accumulation, CDK1 activation and increased proliferation in RB-deficient cells. In RB-proficient cells, cyclin B/CDK1 activation in response to DYRK1A inhibition is neutralized by the RB pathway, resulting in an unchanged proliferation rate. In contrast, complete DYRK1A inhibition with high doses of inhibitors results in massive cyclin B accumulation, saturation of CDK1 activity and cell cycle arrest, regardless of RB status. These findings provide new insights into the complexity of context-dependent DYRK1A signalling in cancer cells.

The white matter is a pro-differentiative niche for glioblastoma

Glioblastomas are hierarchically organised tumours driven by glioma stem cells that retain partial differentiation potential. Glioma stem cells are maintained in specialised microenvironments, but whether, or how, they undergo lineage progression outside of these niches remains unclear. Here we identify the white matter as a differentiative niche for glioblastomas with oligodendrocyte lineage competency. Tumour cells in contact with white matter acquire pre-oligodendrocyte fate, resulting in decreased proliferation and invasion. Differentiation is a response to white matter injury, which is caused by tumour infiltration itself in a tumoursuppressive feedback loop. Mechanistically, tumour cell differentiation is driven by selective white matter upregulation of SOX10, a master regulator of normal oligodendrogenesis. SOX10 overexpression or treatment with myelination-promoting agents that upregulate endogenous SOX10, mimic this response, leading to niche-independent pre-oligodendrocyte differentiation and tumour suppression in vivo. Thus, glioblastoma recapitulates an injury response and exploiting this latent programme may offer treatment opportunities for a subset of patients.

Effect of drying and/or warming piglets at birth under warm farrowing room temperatures on piglet rectal temperature over the first 24 h after birth

Piglets experience a decline in body temperature immediately after birth, and both drying and warming piglets at birth reduce this. However, these interventions may be less effective at higher farrowing room temperatures. This study was carried out at a commercial facility to compare the effect of drying and/or warming piglets at birth on postnatal rectal temperature (RT) under relatively warm farrowing room temperatures (26.6 ± 2.09 °C). Forty-five sows/litters were used in a completely randomized design to compare three Intervention Treatments (applied at birth): Control (no treatment); Warming (piglets placed in a plastic box under a heat lamp for 30 min); and Drying+Warming (piglets dried with desiccant and warmed as above). Temperatures in the warming boxes over the study period averaged 37.7 ± 2.75 °C. At birth, piglets were weighed; RT temperature was measured at 0, 10, 20, 30, 45, 60, 120, and 1,440 min after birth. Blood samples were collected at 24 h after birth from a subsample of one piglet from each birth weight quartile within each litter to measure plasma immunocrit concentration. Data were analyzed using PROC MIXED of SAS with litter as the experimental unit, and piglet as a subsample of litter. The model for analysis of piglet rectal temperature included fixed effects of Intervention Treatment, measurement time (repeated measure), the interaction, and the random effect of sow. Compared with the Control, piglet RT were higher (P ≤ 0.05) for the Warming treatment between 10 and 60 min, and higher (P ≤ 0.05) for the Drying+Warming treatment between 10 and 120 min after birth. Rectal temperatures were higher (P ≤ 0.05) for the Drying+Warming than the Warming treatment between 20 and 120 min. Responses to drying and/or warming were greater for low-birth-weight piglets (<1.0 kg) than heavier littermates, but were generally less than observed in previous experiments with similar treatments carried out under cooler temperatures. Piglet immunocrit values were lower (P ≤ 0.05) for the Drying+Warming treatment compared to the other Intervention Treatments, which were similar (P > 0.05). Immunocrit values tended (P = 0.10) to be lower for light (<1.0 kg) compared with heavier birth weight piglets. In conclusion, drying and warming piglets at birth was more effective for reducing piglet RT decline after birth than warming alone, though the effect was less than observed in previous studies carried out under cooler farrowing room temperatures.

84 Effect of rearing cross-fostered piglets in litters of either uniform or mixed birth weights on pre-weaning performance

There is limited understanding of optimum cross-fostering methods to use to maximize piglet performance. This study evaluated effects of within-litter birth weight variation after cross-fostering on pre-weaning piglet removals (PR; morbidity and mortality) and ADG. A hierarchical incomplete block design was used (blocking factors day of farrowing and sow parity and structure) with a 3x2 factorial arrangement of treatments: 1) Birth Weight Category (BWC): Light (&lt; 1.0 kg), Medium (1.0-1.5 kg), or Heavy (1.5-2.0 kg); 2) Litter Composition (LC): Uniform (piglets of the same BWC), and Mixed (equal numbers of piglets from each BWC). Piglets were weighed 24 h after birth and allotted to form litters of 15 cross-fostered piglets. The experimental unit was 5 piglets of the same BWC (3 experimental units per litter). A total of 102 litters were allotted to 17 blocks of 6 litters (1 Uniform litter of each BWC; 3 Mixed litters) with 51 replicates (3 replicates/block of 6 litters). Weaning weights and PR were measured. PROC GLIMMIX and MIXED of SAS were used to analyze PR and other data, respectively. Models included BWC, LC, the interaction, and replicate within block. There were treatment interactions (P &lt; 0.05) for all measures except birth weight. There was no effect (P &gt; 0.05) of LC on weaning weight or ADG for Light or Medium piglets; Heavy piglets had greater (P &lt; 0.05) weaning weight and ADG in Mixed than in Uniform litters. PR were greater (P &lt; 0.05) for Light piglets in Mixed than in Uniform litters, and for Heavy piglets in Uniform than in Mixed litters. PR for Medium piglets were similar (P &gt; 0.05) across LC treatments. In conclusion, rearing cross-fostered piglets in Uniform litters reduced PR for Light piglets, but increased PR and reduced ADG of Heavy piglets, with no effect for Medium piglets.

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PSV-5 Effect of oxygen administration to piglets at birth on post-natal body temperatures

Newborn piglets are susceptible to hypothermia, and associated mortality. Previous research suggested exposing neo-natal piglets to elevated oxygen concentrations reduced post-natal body temperature decline. This study evaluated the effects of oxygen administration at birth on piglet temperatures over 24 h after birth. This study used 296 piglets (24 litters) and was carried out in a standard farrowing facility consisting of crates within pens with a heat lamp. A GRBD was used; sow was the blocking factor; piglet the experimental unit. A replicate was 3 littermates of similar BW; piglets were randomly allotted at birth within replicate to treatment: 1) Control [dried at birth (with a desiccant); returned to farrowing pen]; 2) Ambient Oxygen (dried; placed in a chamber at ambient temperature and oxygen concentration for 20 min); 3) 40% Oxygen (dried; placed in a chamber at ambient temperature and 40% oxygen concentration for 20 min). Piglets were weighed at birth. Rectal temperature was measured at 0, 20, 30, 45, 60, 90, 120, 180, 240 and 1440 min after birth. Data were analyzed using PROC MIXED of SAS. The model included fixed effects of treatment, time of measurement (repeated measure), and the interaction and random effects of block and replicate. There was no treatment effect (P &gt; 0.05) on temperatures at birth and between 120 and 1440 min. Compared to the Control, temperatures were lower (P &lt; 0.05) for the 40% Oxygen treatment between 20 and 90 min and for the Ambient Oxygen treatment between 20 and 45 min. Temperatures at 60 and 90 min for the Ambient Oxygen treatment were intermediate to and not different (P &gt; 0.05) from the other treatments. Results suggest that exposing neo-natal piglets to an oxygen-rich environment in a chamber does not reduce post-natal temperature decline. This research was funded by the National Pork Board.

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PSV-9 The effect of warming and drying piglets at birth under cool or warm farrowing room temperatures on post-natal rectal temperatures

Piglets are born into a relatively cool environment, resulting in body heat loss, especially at low environmental temperatures. Drying and warming reduces this heat loss, but may be less effective at the higher temperatures experienced in farrowing houses in summer. This study compared the effect of warming and drying piglets at birth on post-natal rectal temperature under winter vs. summer conditions. The study was carried out at a commercial facility using a CRD with 96 sows/litters in a 2×3 factorial arrangement of treatments (applied at birth): 1) Piglet Management: Control (no treatment); Warmed (in a heated box for 30 min); Dried+Warmed (dried with desiccant and warmed); 2) Season: Winter (January-March; farrowing room temperature 21.0 ± 1.65°C); Summer (August-September; 25.3 ± 1.67°C). At birth, piglets were weighed; rectal temperature was measured at 0, 10, 20, 30, 45, 60, 120, and 1440 min after birth. Data were analyzed using PROC MIXED of SAS. Litter was the experimental unit; piglet was a subsample of litter. The model included Season, Piglet Management, and the interaction. There were treatment interactions (P &lt; 0.05) for rectal temperatures at all measurement times except at birth. For both Seasons, the Dried+Warmed treatment resulted in greater (P &lt; 0.05) temperatures than Warmed between 20 and 60 min; both treatments had greater (P &lt; 0.05) temperatures than the Control between 10 and 120 min. Rectal temperatures were lower (P &lt; 0.05) in Winter than Summer for the Control and Warmed treatments between 10 and 60 min. However, for the Dried+Warmed treatment, rectal temperatures were similar between Seasons at all times after 10 min. In conclusion, drying and warming piglets at birth was more effective for reducing rectal temperature decline than warming alone and this effect was greater in winter than summer. This research was funded by the National Pork Board.

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PSII-19 Effect of inclusion level of synthetic lysine, threonine, methionine, and tryptophan in corn-soybean meal and DDGS based diets for grow-finish pigs on growth performance and carcass characteristics

The objective of this study was to determine the effect of increasing dietary synthetic amino acids L-Lysine HCl, L-Threonine, Alimet®, and L-Tryptophan inclusion level at the expense of soybean meal on growth performance during the grow-finish period (46.2 ± 0.55 to 127.4 ± 0.83 kg BW) and carcass characteristics of pigs reared under commercial conditions. The study used a RCBD with 2 dietary treatments: 1). Control: 0.309, 0.029, 0.028, and 0.000 g/kg of synthetic lysine, methionine, threonine, and tryptophan, respectively; 2). High Inclusion: 0.422, 0.069, 0.047, and 0.014 g/kg, respectively. Diets were corn-soybean meal based with DDGS (20.6% for both diets) formulated to be isocaloric and to the same SID amino acid levels but varied in soybean meal inclusion (14.1 and 10.2%, for the Control and High Inclusion, respectively) and crude protein content (17.7 and 16.4%, respectively). A total of 3,520 barrows and gilts were used, housed in single-sex pens of 32 (22 replicates) at a floor space of 0.67 m2/pig. Pigs had ad libitum access to feed and water throughout the study. Pen was the experimental unit and data were analyzed using PROC MIXED of SAS; the model accounted for fixed effect of dietary treatment and the random effect of block. There was no effect of dietary treatment on final live weight, overall ADFI, hot carcass weight, backfat depth, or longissimus muscle depth. However, the High Inclusion treatment had lower overall ADG (P ≤ 0.01) and overall G:F (P ≤ 0.05), but greater (P ≤ 0.01) carcass yield than the Control treatment. These results suggest that increasing the inclusion of synthetic amino acids in corn-soybean and DDGS based diets for growing-finishing pigs to the levels evaluated negatively impacted growth rate and feed efficiency but increased carcass yield.

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