Effect of chronic cyclic heat stress and supplemented inorganic and organic zinc source levels on grow-finish pig growth performance and estimated body composition.

Zinc (Zn) supplementation has proved to mitigate the effects of heat stress with varying effects evident with Zn source during acute heat events. However, the effects of Zn supplementation during long-term summer weather patterns have yet to be explored. Therefore, the objective of this study was to identify the effects of supplementation source and level of Zn to mitigate the negative effects of long-term, cyclic heat stress in finishing swine. Six hundred cross-bred pigs were housed under thermoneutral (TN) or cyclic heat (HS) conditions simulating summer heat with acute 3-d heat waves for a 70-d study. Thermoneutral conditions were 16.7 to 18.9 °C throughout the study. HS pigs were housed at the same temperature as TN from days 0 to 18, then 28 °C/24 °C for 12 h/12 h on days 18 to 21, followed by 30 °C/26.7 °C for 12 h/12 h on days 24 to 70, except during acute heat (32 to 33 °C/29 to 30 °C, 12 h/12 h) on days 21 to 24, 42 to 45, and 63 to 66. Treatments were arranged in a 2 × 6 factorial with main effects of environment (HS vs. TN) and dietary available Zn supplementation: (1) 50 mg/kg zinc oxide (ZnO), (2) 130 mg/kg ZnO, (3) 50 mg/kg of organic Zn (Availa Zn), (4) 50 mg/kg ZnO + 40 mg/kg organic Zn, (5) 50 mg/kg ZnO + 60 mg/kg organic Zn, and (6) 50 mg/kg ZnO + 80 mg/kg organic Zn. Pigs (5 pigs/pen) were blocked by initial body weight (72.2 kg) and randomly allotted to 1 of 12 temperature and diet treatment combinations across 10 replicates. Body weight and feed intake were determined at the beginning and end of each acute heat event. All pigs were ultrasonically scanned at the 10th rib (TR) to predict loin muscle area (LMA), backfat (BF), and percent lean. Data were analyzed by the MIXED procedure in SAS with pen as the experimental unit. At day 63, HS pigs were lighter (P < 0.05), had lower overall average daily gain (ADG; P < 0.05) and average daily feed intake (P < 0.05). A diet-by-environment interaction was observed for overall ADG (P < 0.05) with diet 5 HS pigs having a 3.9% reduction in ADG whereas diet 6 had 14.4% reduction in ADG, while under TN temperatures diet 6 had the greatest overall ADG of all treatments. Other diets were intermediate in their ADG under both HS and TN conditions. Pigs under HS had less BF at the TR (P < 0.05) and a smaller LMA (P < 0.05), and a greater calculated percent lean (P < 0.05). Our results indicate that a blend of supplemental Zn sources at 50/60 mg/kg may mitigate the reduction in growth performance due to HS. While not directly contrasted, the NRC requirement of 50 mg/kg Zn may be too low to optimize finishing pig growth performance under both TN and HS conditions.

Qualitative interviews to evaluate content validity of the ACTIV-2 COVID-19 Symptom Diary (ACSD).

BACKGROUND: Patient-reported outcome measures are needed to assess the impact of treatments for COVID-19 on symptoms. The ACTIV-2 COVID-19 Symptom Diary (ACSD) is being used in the ongoing Accelerating COVID-19 Therapeutic Interventions and Vaccines-2 (ACTIV-2) platform clinical trial. The purpose of the current study was to conduct qualitative interviews to assess content validity of the ACSD. METHODS: Interviews were conducted with adults who had tested positive for SARS-CoV-2. The ACSD begins with global items, followed by a symptom checklist. Each interview began with concept elicitation focusing on participant experiences with COVID-19. Then, participants completed the ACSD, and cognitive interviews were conducted to evaluate the questionnaire. Interviews were recorded, transcribed, and coded following a qualitative content analysis. For the qualitative analysis, a coding dictionary was developed with a list of all potential codes and instructions for how the codes should be applied and combined. RESULTS: Interviews were conducted with 30 participants (mean age = 39 years; 57% female; 17% Latinx; 17% Black/African American; 40% meeting at least one criterion for classification as high risk of progression to severe COVID-19). Commonly reported symptoms included fatigue (reported by 100% of the sample), body pain/muscle pain/aches (87%), headaches (87%), cough (83%), loss of smell (73%), shortness of breath/difficulty breathing (70%), and chills (70%). The 13 symptoms most commonly reported in this study are included in the ACSD. After completing the ACSD, participants consistently reported that it was clear and easy to complete, and all items were generally interpreted as intended. Based on participants' input, the ACSD was edited slightly after the first 13 interviews, and the revised version was used for the final 17 interviews. Two additional items assessing "brain fog" and dizziness were recommended for addition to the ACSD in future research. CONCLUSIONS: This qualitative study supports the content validity of the ACSD for assessment of COVID-19 symptoms. Quantitative research with larger samples will be needed to examine the questionnaire's measurement properties.

This study focused on the ACTIV-2 COVID-19 Symptom Diary (ACSD), a questionnaire that assesses symptom severity of COVID-19. The ACSD begins with global items assessing overall symptom severity, followed by a symptom checklist focusing on individual symptoms. Interviews were conducted with 30 adults who had tested positive for COVID-19. The patients reported their experiences with COVID-19, completed the ACSD, and provided their opinions about the ACSD. Based on input from these patients, the ACSD appears to be clear and easy to complete, and it includes the most common and important symptoms of COVID-19. The ACSD was edited for clarity, and "brain fog" and dizziness were recommended additions for future research. This study suggests that the ACSD is a useful questionnaire for assessment of COVID-19 symptoms in clinical studies. Studies like this are important for ensuring that symptoms are measured appropriately and accurately in clinical trials. Future research with larger samples will be needed to further examine the questionnaire.

The effect of reduced CP, synthetic amino acid supplemented diets on growth performance and nutrient excretion in wean to Finish swine.

Mixed sex pigs (n = 720) were placed in 12 rooms (Purdue Swine Environmental Research Building) to measure the effect of reduced crude protein (CP), amino acid (AA)-supplemented diets on growth and the carcass. Pigs were blocked by body weight (BW) and gender and allotted to room and pen (10 mixed-sex pigs/pen). Pigs were fed a nine-phase, wean-finish program. Control pigs consumed corn-soybean meal-distiller's dried grains with solubles (DDGS) diets containing no to minimal (Met) synthetic AA. The 2X diet was formulated to meet the seventh most-limiting AA, and balanced using synthetic AAs to meet all AA needs. The 1X diet was formulated to meet a CP value halfway between the control and 2X diet, and also balanced using synthetic AAs to meet all AA needs. Diets were formulated to identical net energy concentrations and balanced to meet standard ileal digestible NRC 2012 AA requirements. Pit vacuum samples were collected at the end of each growth phase for analyses of nitrogen, C and dry matter (DM). Pigs fed the Control and 1X diet grew faster (P < 0.005), had greater gain:feed (P < 0.001), and were heavier at market (P < 0.001) than animals fed the 2X diet. No consistent effects of diet were observed on average daily feed intake. Carcass data were analyzed for sex, diet and sex*diet effects. Reductions in dietary CP resulted in a linear reduction in ammonium nitrogen excretion per kg of BW gain in Nursery (P < 0.001) and Grow-Finish (P < 0.001) phases. Reductions in dietary CP, with synthetic AA supplementation resulted in a linear reduction in total nitrogen excreted per kg BW gain in the Grow-Finish phase (P < 0.001) and overall (P < 0.001). Total mineral excretion per kg gain was reduced in pigs fed 1X and 2X diets compared with control-fed pigs (P < 0.005). Reductions in dietary CP of ~3 and 5%-units from wean-finish result in reductions of total N excretion of 11.7 and 24.4%, respectively. Reduced performance and carcass characteristics observed in pigs fed the 2X diets indicates an inaccurate estimate of NRC 2012 AA requirements or ratios to lysine in a low CP diet.

Biomarkers predictive of long-term fertility found in vaginal lipidome of gilts at weaning.

A marker indicative of the fertility potential of replacement gilts early in development would decrease culling rates in the sow herd, improve sow herd reproductive efficiency, and reduce production costs. The objective of this study was to determine if vaginal lipid profiles at 21 d postnatal (PN) could predict sow reproductive performance. Vaginal swabs of the anterior vagina were taken at 21 ± 4 d PN from gilts born on a commercial sow production facility for lipidomic analysis. Animals were followed prospectively for 2 yr and assigned to reproductive performance categories based on the observation of estrus or piglets weaned per sow per year (PSY) across two farrowings. Lipids were extracted from cellular material collected with swabs taken from high fertility (HF; n = 28; ≥26 PSY) and infertile (IF; n = 34; no estrus, no pregnancy) animals, and multiple reaction monitoring profiling was used for lipidome analysis. The relative abundance of arachidonic acid (C20:4) and docosahexaenoic acid (C22:6) was lower (P < 0.05) in IF gilts than HF gilts, whereas the abundance of the free fatty acids such as cerotic (C26:0), ximenic (C26:1), and nonadecanoic (C19:0) acids was greater (P < 0.05) in IF gilts. Additionally, eicosapentaenoic acid (C20:5), a precursor of prostaglandins, was higher (P < 0.05) in IF gilts. The perspective of having a panel of lipids captured with vaginal swabs at weaning that can predict the reproductive efficiency of gilts shows promise and warrants future research in this area.

Effects of induction on the farrowing process and piglet blood parameters at the time of farrowing.

Historically, sows have been induced to farrow using prostaglandin followed by an injection of oxytocin 24 h later. Benefits of induction can include decreased rate of stillbirths, dystocia, and postnatal mortality along with increasing the likelihood of farrowings being attended. Several studies have indicated that oxytocin administration may negatively impact fetal oxygen supply during parturition, potentially from umbilical cords breaking prior to birth, resulting in increased preweaning mortality. Therefore, the objective of this study was to determine if various induction protocols impact umbilical cord breakage and fetal blood parameters at birth. Fifty-eight primiparous and multiparous sows were assigned to one of three treatments: no induction (NO; n = 24) or 2 cc prostaglandin administered on day 114 of gestation followed by either 1 cc of oxytocin 24 h later (OXY24; n = 13) or 0.5 cc of oxytocin at 6 and 12 h after prostaglandin (OXY6; n = 21). Details of the farrowing process were recorded, and umbilical cord blood was collected from piglets at birth and evaluated on an iSTAT machine using an Abbott EC8+ test cartridge. There were no differences in total born, number born alive, stillborns, mummies, or assistance needed during farrowing. Induced sows were more likely to farrow by day 115 compared to naturally farrowing sows (P = 0.02). Sows in the OXY24 treatment tended to have longer farrowings when compared to both NO and OXY6 (4.8 vs. 3.6 vs. 3.9 h; P = 0.09). Colostrum from OXY6 sows tended to have a greater amount of lactose present than NO and OXY24 (P = 0.05). Colostrum from sows with longer gestation lengths had a higher percentage of fat (P = 0.03). Piglets born from NO sows had higher base excess, total carbon dioxide, and glucose, which suggests that these piglets had prolonged moments of asphyxiation (P < 0.01). OXY24 piglets had the lowest blood pH which is indicative of hypoxic birthing conditions (P < 0.01). Preweaning mortality was driven largely by a low birth weight coupled with low colostrum intake (P = 0.03). All piglets, regardless of treatment, displayed signs of stress during farrowing. Induction did not influence preweaning mortality but has the potential to decrease the incidence by increasing attended farrowings.

Shotgun proteome analysis of seminal plasma differentiate boars by reproductive performance.

There is a need to identify subfertile boars before they enter into the breeding herd. Seminal plasma proteins are essential for normal sperm function and transport and play an important role in fertilization. The objective of this study was to use liquid chromatography tandem mass spectrometry for shotgun proteome analysis to investigate whether differences in boar fertility phenotype can be differentiated by seminal plasma protein abundance. Following 50 breedings, boars were categorized into one of four phenotypes: high farrowing rate and total born (HFHB; n = 9), high farrowing rate with low total born (HFLB; n = 10), low farrowing rate and total born (LFLB; n = 9), and low farrowing rate with high total born (LFHB; n = 4) that were distinct (p < 0.05) from each other by these variables. There were 506 proteins measured in at least one sample across all animals. There were 245 high confidence proteins and 56 were differentially abundant between the high fertility phenotype (HFHB) and at least one of the three subfertile groups. Findings support that seminal plasma protein profiles are distinct between boars with different fertility phenotypes.

Evaluation of on-farm indicators of gilt reproductive performance potential at 21 days of age.

Selection of replacements for the sow herd is one of the most important facets in swine production. Although our current methods of selection are effective, there is still a large amount of variation in sow reproductive performance traits such as pigs per sow per year (PSY). Therefore, the objective of this study was to determine if on-farm phenotypic traits at 21 d postnatal (PN) or perinatal environmental factors could predict sow reproductive performance. Data were prospectively collected from 2,146 gilts born on a commercial sow production facility and included birth and weaning weights, vulva length and width at 21 d PN, birth and nursing litter size, days nursed, average daily gain from birth to weaning, and age at first estrus. Of the initial animals, 400 (17%) were selected for the sow herd, 353 remained after removal of animals culled for non-reproductive reasons. Animals were assigned to 1 of 5 reproductive performance categories based on observation of estrus or pigs per sow per year (PSY) across two farrowings: High Fertility (HF; 23%; n = 82; ≥26 PSY), Middle Fertility (MF2; 12%; n = 43; 20-25 PSY), Low Fertility (MF3; 15%; n = 54; <20 PSY), Infertile-Estrus (IFe; 10%; n = 36; estrus, no pregnancy), and Infertile-No Estrus (IFno; 39%; n = 138; no estrus, no pregnancy). Generalized linear model analysis indicated vulva width (P = 0.03) was related to PSY, however, it only explained 1.5% of the total variation in PSY. To determine if preweaning variables were predictive of gilt fertility outcome, animals were grouped as those that became pregnant (n = 179) or not (n = 174). Vulva width tended to be greater in fertile animals versus infertile (P = 0.07). Binomial regression analysis revealed a positive relationship between vulva width and gilt fertility, however, this relationship is not strong enough to make sow herd selection decisions.