Adenocarcinoma of the distal esophagus and esophageal-proventricular junction in a yellow-naped parrot.

A 57-y-old male yellow-naped parrot (Amazona auropalliata) was presented because of lethargy, inappetence, and weight loss. Hematology and serum biochemistry were unremarkable, and imaging revealed a mass in the distal esophagus at the coelomic inlet. The luminal diameter of the esophagus was reduced in this area, and passage of ingesta was limited. Following gavage feeding, the patient died and was submitted for autopsy. At postmortem examination, the noted mass effect was a thickening of the distal esophagus with adherent, coalescing, soft, pale-tan plaques on the mucosal surface. Additional gross findings included pale-tan, opaque feed material oozing from the dorsum of the lungs and covering the cranial air sacs. Histology of the esophagus, esophageal-proventricular junction, and proximal proventriculus revealed an unencapsulated, infiltrative, transmural neoplasm that extended from the mucosal surface deep into the muscularis, almost to the adventitia. The neoplasm was composed of cuboidal cells arranged in islands and tubules, consistent with an adenocarcinoma, a rarely reported entity in the esophagus of psittacine birds and to our knowledge not reported previously at the esophageal-proventricular junction.

Fabrication and In Vivo Assessment of Oxidatively Responsive PolyHIPE Scaffolds for Use in Diabetic Orthopedic Applications.

Achieving surgical success in orthopedic patients with metabolic disease remains a substantial challenge. Diabetic patients exhibit a unique tissue microenvironment consisting of high levels of reactive oxygen species (ROS), which promotes osteoclastic activity and leads to decreased bone healing. Alternative solutions, such as synthetic grafts, incorporating progenitor cells or growth factors, can be costly and have processing constraints. Previously, the potential for thiol-methacrylate networks to sequester ROS while possessing tunable mechanical properties and degradation rates has been demonstrated. In this study, the ability to fabricate thiol-methacrylate interconnected porous scaffolds using emulsion templating to create monoliths with an average porosity of 97.0% is reported. The average pore sizes of the scaffolds range from 27 to 656 µm. The scaffolds can sequester pathologic levels of ROS via hydrogen peroxide consumption and are not impacted by sterilization. Subcutaneous implantation shows no signs of acute toxicity. Finally, in a 6-week bilateral calvarial defect model in Zucker diabetic fatty rats, ROS scaffolds increase new bone volume by 66% over sham defects. Histologic analysis identifies woven bone infiltration throughout the scaffold and neovascularization. Overall, this study suggests that porous thiol-methacrylate scaffolds may improve healing for bone grafting applications where high levels of ROS hinder bone growth.

Acute carpal tunnel syndrome from thrombosed persistent median artery in a patient with congenitally absent radial artery.

OBJECTIVES: Thrombosis of the persistent median artery (PMA) is a rare cause of acute carpal tunnel syndrome (ACTS). Existence of a congenitally absent radial artery in this setting has not been described in the literature. METHODS: Computed Tomography Angiography (CTA) and doppler screening were used in pre surgical planning. Open surgical decompression was achieved through the release of the flexor retinaculum in the left hand. A regimen of 100 mg of Aspirin for 3 months time was initiated to encourage clot resolution and recanalization of the thrombosed artery. RESULTS: The PMA was found to be abnormally large measuring approximately 4 mm in diameter. Visible clotting off of the PMA in keeping with the doppler scans with maintenance of distal flow and was left intact with the hopes that it would recanalize over time. At the 3-month post-op review the antiplatelet therapy was ceased and the patient was symptom free, demonstrated no signs of ischaemia in the hand, and had returned to full functionality and physical activity. CONCLUSIONS: Although infrequently encountered, the knowledge of the anatomical variations of the forearm and hand together with doppler screening and CTA is essential to the surgical management of ACTS.

H-ferritin in sows' colostrum- and milk-derived extracellular vesicles: a novel iron delivery concept.

Iron deficiency anemia is a significant problem in piglets, as they are born with insufficient iron stores for supporting their rapid body growth. Further, sows' milk contains inadequate iron levels for meeting the demands of piglet rapid growth in the pre-wean stage. The forms of iron present in the milk are essential to understanding bioavailability and potential routes for supplementing iron to mitigate iron deficiency anemia in piglets. Recently, our studies showed that H-ferritin (FTH1) is involved in iron transport to different tissues and can be used as an oral iron supplement to correct iron deficiency in rats and monkeys. In this study, we investigate the FTH1 levels in colostrum and milk in Yorkshires-crossbred sows (n = 27) and collected samples at the 1st, 15th, and 28th days of lactation to measure FTH1. Colostrum and milk were found to have FTH1, but there is no significant difference between the different days of lactation. FTH1 has been observed to be enriched in extracellular vesicles (EVs) of other species, and therefore examined the EVs in the samples. Colostrum-derived EVs were enriched with L-ferritin compared to FTH1, while in milk-derived EVs, only FTH1 was detected (P = 0.04). In milk-derived EVs, FTH1 was significantly higher (P = 0.021; P = 006) than FTH1 in colostrum-derived EVs. Furthermore, FTH1 levels of milk-derived EVs were significantly higher (P = 0.0002; P = 0004) than whole milk and colostrum FTH1. These results indicate that FTH1 is enriched in the milk-derived EVs and suggest that EVs play a predominant role in the FTH1 delivery mechanism for the piglet. The extent to which FTH1 in EVs accounts for the overall iron delivery mechanism in piglets is yet to be determined.

Colostrum and milk are the primary sources of nutrition for lactating mammals. Iron is an essential nutrient for nursing mammals. Piglets are routinely iron deficient and do not obtain adequate iron from sows' milk further contributing to anemia observed in young pigs. Additional information about the proteins that carry iron from the sow's breast milk to understand the bioavailability of iron and potential routes for reducing the incidence of anemia in offspring are clearly needed. We have discovered that H-ferritin (FTH1) is a potent iron transport protein and is not limited to iron storage as previously thought. Therefore, our objective was to determine whether the FTH1 is present in the sow's colostrum and milk. Furthermore, there are extracellular vesicles released from cells that are known to transport FTH1 and are reportedly present in sows' milk. Our study showed that FTH1 was present in the colostrum and milk and enriched in the milk-derived EVs. This study reveals a new protein and mechanism for iron delivery during lactation in sows that may be targeted to decrease iron deficiency in piglets.

Changes in unintentional cannabis exposures in children 6 months to 5 years reported to United States poison centers during the first nine months of the coronavirus-19 pandemic.

INTRODUCTION: Almost half of exposures reported to United States (US) poison centers are exploratory ingestions in children under the age of 5 years. Pediatric cannabis exposures reported to US poison centers have risen over the last twenty years, with greater increases in the last 5 years. In 2020, the Coronavirus disease 2019 (COVID-19) pandemic resulted in widespread stay-at-home orders and subsequent changes in work, education, and daycare. This study describes the changes in pediatric cannabis exposures during the first nine months of the COVID-19 pandemic relative to the three years before the pandemic. METHODS: Cases were identified from the National Poison Data System. Inclusion criteria was unintentional cannabis exposure in children aged 6 months to 5 years between January 1, 2017 and December 31, 2020. Analysis was performed with segmented regression of interrupted time series analysis comparing January 2017-March 2020 (pre-COVID-19) to April 2020-December 2020 (COVID-19 period). Autocorrelation was assessed using Dubin-Watson test. RESULTS: There were 7,679 unintentional pediatric exposures from January 1, 2017 through December 31, 2020. There was a significant increase of 3.1% per month during the pre-COVID-19 period (p < .0001). A statistically significant immediate increase in number of exposures per month occurred in April 2020 (58.4%; p < .0001). The slope in the COVID-19 period was -0.01% (p = .99). No autocorrelation was detected. DISCUSSION AND CONCLUSIONS: Unintentional cannabis exposures in children aged 6 months to 5 years reported to United States poison centers increased significantly after the initial COVID-19 stay-at-home orders. This trend may be associated with COVID-19 quarantines, increased time children are spending at home, increased availability of cannabis products in homes, or other reasons. Future efforts should evaluate specific factors that resulted in the observed increases in pediatric exposures.

Critical care interventions in children aged 6 months to 12 years admitted to the pediatric intensive care unit after unintentional cannabis exposures.

BACKGROUND: Cannabis exposures in children have risen sharply in recent years, resulting in increased hospital visits and admission to pediatric intensive care units (PICUs). The intent of this study was to describe the proportion of pediatric patients admitted to the PICU after unintentional cannabis ingestion that received critical care interventions (CCIs) along with describing trends over time in hospitalization, admission to the PICU, and clinical effects and treatments outside of the PICU. METHODS: This was a retrospective database study utilizing the National Poison Data System (NPDS) from 1/1/2000 to 12/31/2020. Children 6 months to 12 years of age with single substance cannabis exposures were included. RESULTS: A total of 12,882 cases were included. There was an increase in the proportion of cases seen in a hospital over time from 43.8% in 2000 to 54.6% in 2020 (range 29.1-62.6%). In patients seen in a HCF, the proportion admitted to the PICU was 9.5% in 2000 and 14% in 2020 (range: 5.6-29.0%). The 875 (6.8%) children admitted to the PICU were analyzed for the primary outcome. CCIs were performed in 69/875 (7.9%) cases that were admitted to the PICU. The most common CCIs in the PICU were intubation and sedation, 4.9 and 3.7%, respectively. CONCLUSIONS: Unintentional pediatric cannabis exposures are associated with clinically significant effects, including respiratory depression, hypotension, and bradycardia, but fewer than 5% of exposures were treated with CCIs, like intubation or vasopressors, in patients admitted to the PICU. Further work should assess specific reasons for admission to the PICU.

Bacterial infection of fasciotomy wounds following decompression for acute compartment syndrome.

OBJECTIVE: Acute Compartment Syndrome (ACS) is a serious complication generally requiring treatment with an emergency decompressive fasciotomy. The aim of this study was to identify the most prevalent organisms involved in fasciotomy wound infections, and to determine the best strategies to mitigate this risk. DESIGN: Retrospective review. SETTING: Single tertiary referral centre. PATIENTS/PARTICIPANTS: Patients (n = 370) who underwent fasciotomy for emergency ACS were included in this study. Positive wound swabs and tissue samples within 30 days post fasciotomy were identified, and extended antibiotic sensitivities were recorded. Patient medical charts were reviewed to assess infection rate, causative organism(s), and clinical outcomes. INTERVENTION: Fasciotomy Main Outcome Measurements: Most prevalent organism in fasciotomy wound infections, and the rate of any associated morbidity and mortality. RESULTS: The overall infection rate was 16.7%. Infection rates were significantly higher in burns (27%) and trauma (22%) patients than vascular patients (13%) (p = 0.002). The most prevalent organism was Pseudomonas aeruginosa, isolated from 23% of all wound specimens and comprising over a third (35%) of infections overall. Ten patients required amputation for infection control. Six of these were secondary to Pseudomonas infection, whereby one patient mortality occurred. CONCLUSION: In this series, one in six fasciotomies for ACS developed an infection within 30 days of their index procedure. Burns and trauma comprised the highest risk groups. Facultative anaerobes were the predominant organisms involved in fasciotomy wound infections. A combination of aminoglycosides and beta-lactams with quinolones should be considered when commencing empiric therapy for fasciotomy wound infections. Antibiotic coverage for routine peri­operative prophylaxis following emergency decompression for acute compartment syndrome should be strongly considered, particularly in burns or trauma cases. LEVEL OF EVIDENCE: Aetiologic Level III.

Measuring birth weight and umbilical cord diameter at birth to predict subsequent performance in swine.

In the swine industry, pre-weaning mortality, umbilical hernia incidence and pig market weight are a few contributing factors affecting profitability and welfare on farm. Therefore, the ability to reliably predict any of these outcomes is valuable to swine operations. Mortality during the pre-weaning phase, umbilical hernia incidence and poor-quality finisher pigs can represent a multi-million dollar loss and increase in welfare concerns to the producer. Consequently, the objective of this study was to evaluate whether birth weight (BW), umbilical cord diameter at birth (UCD), and the calculated umbilical diameter at birth to birth weight ratio (UCD:BW), are potential indicators of both placental efficiency and relative defect size in the abdominal musculature as well as reliable predictors of pre-weaning mortality, umbilical hernia incidence, and pig body weight at 150 d of age in a commercial facility. Mixed sex commercial piglets were followed through production. Four hundred sixty-five piglets were weighed within 1 h of birth, and the UCD was determined using digital calipers, these animals were followed through weaning. Three hundred eighty-five pigs of the 465 were followed through the post-wean phase in the nursery facility and checked for umbilical hernia incidence. Finally, of the 385 pigs, 177 pigs were assessed for umbilical hernia incidence and weighed a final time at the grower-finisher facility. All data were analyzed using PROC Logistic and PROC GLM procedures. The variables of UCD:BW and BW were significantly associated with the probability of increased pre-weaning mortality (P < 0.001). For example, piglets with a low UCD:BW, but an increased BW had the greatest survival rate. Umbilical diameter (UCD) was not significantly associated with pre-weaning mortality. Post-weaning mortality was not significantly affected by UCD:BW, BW, or UCD variables. Umbilical hernia incidence was not significantly affected by UCD:BW at the nursery phase or growing-finishing phase. Pig body weight at 150 d of age was significantly affected by UCD:BW, BW, and UCD variables (P < 0.001). For example, piglets that had a larger UCD weighed more at 150 d of age. In conclusion, measuring the calculated UCD:BW has the potential to be a novel tool for future research looking into the impacts of umbilical measurements as it relates to placental function, fetal development, piglet survivability and impacts on future performance of the animal.

Fibrous osteodystrophy in a dromedary camel.

A 6-y-old female dromedary camel (Camelus dromedarius L.) was presented for assessment of firm, bilateral swellings rostral and ventral to the eyes. Serum biochemistry revealed hyperglycemia (28.5 mmol/L), hypocalcemia (1.27 mmol/L), hyperphosphatemia (3.39 mmol/L), hypoproteinemia (total protein 50 g/L), and hypoalbuminemia (20 g/L). Based on the poor prognosis associated with the presumptive diagnosis of fibrous osteodystrophy, the camel was euthanized. Gross postmortem findings revealed expanded fibrous tissue replacing the maxilla and mandible, and bilaterally prominent parathyroid glands. Histology of the maxilla revealed proliferative loose fibrous tissue with widely scattered, regularly spaced, small spicules of mineralized bone. The parathyroid glands were prominent bilaterally; the internal and external parathyroid glands were composed of plump cells with abundant pale basophilic cytoplasm and open nuclei. The pathologic findings were consistent with the antemortem diagnosis of fibrous osteodystrophy. The camel's diet, which was not specifically balanced for a camel, included grass hay, sweet feed, and alfalfa pellets. The camel's caregivers reported feeding her treats of cookies. A feed analysis was not available. The biochemistry abnormalities and clinical and postmortem findings, along with a diet that was not balanced for a camel, are consistent with a diagnosis of nutritional secondary hyperparathyroidism.

Smooth Muscle Differentiation Is Essential for Airway Size, Tracheal Cartilage Segmentation, but Dispensable for Epithelial Branching.

Airway smooth muscle is best known for its role as an airway constrictor in diseases such as asthma. However, its function in lung development is debated. A prevalent model, supported by in vitro data, posits that airway smooth muscle promotes lung branching through peristalsis and pushing intraluminal fluid to branching tips. Here, we test this model in vivo by inactivating Myocardin, which prevented airway smooth muscle differentiation. We found that Myocardin mutants show normal branching, despite the absence of peristalsis. In contrast, tracheal cartilage, vasculature, and neural innervation patterns were all disrupted. Furthermore, airway diameter is reduced in the mutant, counter to the expectation that the absence of smooth muscle constriction would lead to a more relaxed and thereby wider airway. These findings together demonstrate that during development, while airway smooth muscle is dispensable for epithelial branching, it is integral for building the tracheal architecture and promoting airway growth.

Iron Packaging Regulations in the United States and Pediatric Morbidity: A Retrospective Cohort Study.

Iron poisoning was a leading cause of pediatric morbidity and mortality. We sought to assess whether the removal of strict iron packaging requirements in 2003 resulted in an increase in iron-related morbidity and mortality in pediatric exposures. We performed a retrospective cohort study utilizing the National Poison Data System from 2000 to 2017. A total of 4110 exposures met inclusion criteria: 847 from before (2000-2003) and 3263 after removal of unit-dose package regulations (2004-2017). The incidence of any marker of severity (7.2% vs 3.8%; odds ratio = 0.51, 95% confidence interval = 0.37-0.69) and frequency of deferoxamine use were both higher in the early time period (2.6% vs 1.0%; odds ratio = 0.38, 95% confidence interval = 0.22-0.66). There was no difference in the frequency of key serious effects (acidosis, elevated transaminases, hypotension). Despite removal of iron packaging regulations in the United States, there continues to be a decrease in the incidence of severe iron exposures in children.

Toxicity of acute exploratory amphetamine-salt medication in amphetamine-naïve pediatrics: a retrospective cohort study.

Background and Objectives: Pediatric ingestions of amphetamines used in the treatment of Attention Deficit Hyperactivity Disorder (ADHD) are on the rise. Little data provide an amphetamine dose at which to refer pediatric unintentional ingestions to a healthcare facility for monitoring. We studied the dose at which unintentional ingestions of amphetamines develop symptoms and receive benzodiazepines.Methods: We performed a retrospective study from a single poison center from 1/1/2005 through 11/30/2018. We included single substance ingestion of amphetamine salts to treat ADHD in amphetamine-naïve children age 0-12 years followed to a known outcome. Poison center documentation was reviewed for signs and symptoms related to amphetamine toxicity and use of benzodiazepines.Results: We screened 1,394 cases and 160 met inclusion criteria. The mean age of patients was 1.8 years and 55% were male. The median dose of symptomatic patients (1.38 mg/kg) was greater than those without symptoms (0.83 mg/kg). The median amphetamine dose of patients receiving benzodiazepines (1.58 mg/kg) was also greater than for patients not receiving benzodiazepines (1.0 mg/kg). A dose threshold of greater than 0.75 mg/kg was 100% sensitive and 36.8% specific for benzodiazepine administration and 93.9% sensitive and 47.4% specific for presence of any symptoms.Conclusions: The median dose of amphetamines ingested by patients receiving benzodiazepines was greater than those not receiving benzodiazepines. No child with a dose of ≤0.75 mg/kg received benzodiazepines. Prospective studies should be performed to assess triage guidelines and referral doses.

Prime eligible poisons: identification of extremely hazardous substances available on Amazon.com®.

Background: Widespread use of the Internet has increased availability of numerous products. Multiple published cases highlight that toxic xenobiotics are available for purchase online. Most cases describe purchase from the deep web. We sought to identify extremely hazardous substances available from an online retailer.Methods: Over a 10-month period, the online retailer Amazon.com® was searched for each of the products listed by the Environmental Protection Agency's "List of Extremely Hazardous Substances." Product names, availability on Amazon Prime®, need for a business account, price, and quantity were collated.Results: We identified 79/340 (23.2%) of these substances were available on Amazon.com®. Almost one-third of the available substances were eligible for Amazon Prime®. Approximately one-third of the products were available in an amount that could be toxic by purchasing a single unit (31/79). Of these 31 products, only four required a business account, 18 were eligible for Amazon Prime®, and nine were neither eligible for Prime nor required a business account. Notable products include sodium azide, acrylamide, mercuric acetate, and hydrazine.Conclusions: The ease of purchase and ready availability of such highly toxic substances is concerning. Online retailers like Amazon.com® should consult with toxicologists or other qualified experts and governmental agencies to identify which products should be removed or restricted to business accounts.

Clinical utility of venoarterial-extracorporeal membrane oxygenation (VA-ECMO) in patients with drug-induced cardiogenic shock: a retrospective study of the Extracorporeal Life Support Organizations' ECMO case registry.

Background: Venoarterial-extracorporeal membrane oxygenation (VA-ECMO) is increasingly utilized to treat severe or refractory drug-induced cardiovascular shock. There is limited evidence regarding VA-ECMO's clinical utility in poisoning. Therefore, we investigated the clinical benefit of VA-ECMO use in drug-induced cardiovascular shock using the Extracorporeal Life Support Organization (ELSO)'s ECMO case registry.Methods: The ELSO registry was systematically searched retrospectively, using ICD-9/10 codes for poisoning-related cases from January 1, 2003 to July 30, 2018. All adult cases (age ≥ 18 years) that received VA-ECMO for cardiac support were included. Cardiogenic shock was defined as systolic blood pressure (SBP) <90 mmHg, mean arterial pressure (MAP) <65 mmHg, or requiring infusion of ≥2 vasopressor agents. Study outcomes included survival to discharge (i.e., from the ECMO center), changes in metabolic (acid/base), hemodynamic and ventilatory status, and complications related to ECMO support. Demographic and clinical characteristics of pre-ECMO and 24-h after VA-ECMO cannulation were compared between survivors vs. non-survivors.Results: A total of 113 cases were identified from the ELSO registry; 9 cases were excluded because cardiogenic shock was not related to poisoning, leaving 104 cases for analysis. The median age was 34 years and 53.5% (n = 54) were male. Cardiovascular agents were involved in 47.1% (n = 49) of the cases followed by opioids (n = 9, 6.7%); 34 cases experienced pre-ECMO cardiac arrest. About 92.4% of the cases (n = 85) received vasopressor infusion for hemodynamic support, most frequently norepinephrine (83.7%). Median duration of VA-ECMO was 68 h (interquartile range [IQR]: 48, 113 h); 52.9% (n = 55) of the cases survived to discharge. VA-ECMO significantly improved hemodynamics (MAP, SBP, and DBP), acidemia/acidosis (pH, HCO3 level) and ventilatory parameters (pO2, SpO2, and SvO2). Non-survivors showed persistent acidemia/acidosis at 24-h after VA-ECMO cannulation compared to survivors. Renal replacement therapy (50.9%) and arrhythmia (26.3%) were the most frequently reported complications.Conclusions: VA-ECMO improved hemodynamic and metabolic parameters in patients with drug-induced cardiogenic shock (DCS).

The impact of dietary supplementation of arginine during gestation in a commercial swine herd: II. Offspring performance.

Arginine (Arg) is an important amino acid of pig fetal development; however, whether Arg improves postnatal performance is ill-defined. Therefore, the influence of Arg supplementation at different gestational stages on offspring performance was evaluated in a commercial swine herd. Sows (n = 548) were allocated into 4, diet by stage of gestation treatments: Control (n = 143; 0% suppl. Arg), or dietary treatments supplemented with 1% L-Arg (free-base; Ajinomoto Animal Nutrition North America, Inc., Chicago, IL): from 15 to 45 d of gestation (n = 138; Early-Arg); 15 d of gestation to farrowing (n = 139; Full-Arg); and from day 85 of gestation to farrowing (n = 128; Late-Arg). All offspring were individually identified and weighed at birth; at weaning, a subset was selected for evaluation of carcass performance at market. All data were analyzed using birth weight (BiWt) and age as covariates. Wean weights (WW) and prewean (PW) ADG tended to increase (P = 0.06) in progeny from sows supplemented with Arg, as compared to progeny from Control sows. Preplanned contrast comparisons revealed an increased (P = 0.03) BiWt for pigs from sows receiving 1% L-Arg prior to day 45 of gestation (Early-Arg and Full-Arg; 1.38 kg/pig), as compared to pigs from sows not supplemented prior to day 45 of gestation (Control and Late-Arg; 1.34 kg/pig). No difference in BiWt was observed (1.36 kg/pig; P = 0.68) for Arg supplementation after day 85 of gestation (Full-Arg and Late-Arg), as compared to those not receiving Arg supplementation after day 85 (Control and Early-Arg); although WW and PW ADG were greater (P = 0.02), respectively. A 3.6% decrease (P = 0.05) in peak lean accretion ADG occurred when dams received 1% L-Arg prior to day 45 of gestation (Early-Arg and Full-Arg), however, no other significant differences were detected in finishing growth parameters or carcass characteristics (P ≥ 0.1). Pig mortality rates tended (P = 0.07) to decrease in progeny of dams supplemented Arg after day 85 (3.6%) compared to dams not provided additional Arg during late gestation (4.9%). Collectively, these data suggest that Arg provided during late gestation may improve WW and PW ADG, however, finishing performance was not affected. While Arg supplementation provided some moderate production benefits, further investigation is warranted to comprehensively understand the gestational timing and biological role of Arg supplementation during fetal and postnatal development in commercial production systems.

Crouzon syndrome mouse model exhibits cartilage hyperproliferation and defective segmentation in the developing trachea.

Crouzon syndrome is the result of a gain-of-function point mutation in FGFR2. Mimicking the human mutation, a mouse model of Crouzon syndrome (Fgfr2342Y) recapitulates patient deformities, including failed tracheal cartilage segmentation, resulting in a cartilaginous sleeve in the homozygous mutants. We found that the Fgfr2C342Y/C342Y mutants exhibited an increase in chondrocytes prior to segmentation. This increase is due at least in part to over proliferation. Genetic ablation of chondrocytes in the mutant led to restoration of segmentation in the lateral but not central portion of the trachea. These results suggest that in the Fgfr2C342Y/C342Y mutants, increased cartilage cell proliferation precedes and contributes to the disruption of cartilage segmentation in the developing trachea.

The impact of dietary supplementation of arginine during gestation in a commercial swine herd: I. Gilt reproductive performance.

Supplemental arginine (Arg) during gestation purportedly benefits fetal development. However, the benefits of a gestational Arg dietary strategy in commercial production are unclear. Therefore, the objectives of this study examined Arg supplementation during different gestational stages and the effects on gilt reproductive performance. Pubertal gilts (n = 548) were allocated into 4 treatment groups: Control (n = 143; 0% supplemental Arg) or 1 of 3 supplemental Arg (1% as fed) treatments: from 15 to 45 d of gestation (n = 138; Early-Arg); from 15 d of gestation until farrowing (n = 139; Full-Arg); or from 85 d of gestation until farrowing (n = 128; Late-Arg). At farrowing, the number of total born (TB), born alive (BA), stillborn piglets (SB), mummified fetuses (MM), and individual piglet birth weights (BiWt) were recorded. The wean-to-estrus interval (WEI) and subsequent sow reproductive performance (to third parity) were also monitored. No significant effect of supplemental Arg during any part of P0 gestation was observed for TB, BA, SB, or MM (P ≥ 0.29). Offspring BiWt and variation among individual piglet birth weights did not differ (P = 0.42 and 0.89, respectively) among treatment groups. Following weaning, the WEI was similar among treatments (average of 8.0 ± 0.8 d; P = 0.88). Litter performance over 3 parities revealed a decrease (P = 0.02) in BA for Early-Arg fed gilts compared with all other treatments, whereas TB and WEI were similar among treatments over 3 parities (P > 0.05). There was an increased proportion of sows with average size litters (12 to 16 TB) from the Full-Arg treatment sows (76.8% ± 3.7%) when compared with Control (58.7% ± 4.2%; P = 0.01); however, the proportion of sows with high (>16 TB) and low (<12 TB) litters was not different among treatments (P = 0.20). These results suggest that gestational Arg supplementation had a minimal impact on reproductive performance in first parity sows. These data underscore the complexity of AA supplementation and the need for continued research into understanding how and when utilizing a gestational dietary Arg strategy can optimize fetal development and sow performance.