Feed Delivery Research Articles

Nutrition in the Neurocritical Care Unit: a New Frontier.

Purpose of ReviewThis review presents the most current recommendations for providing nutrition to the neurocritical care population. This includes updates on initiation of feeding, immunonutrition, and metabolic substrates including ketogenic diet, cerebral microdialysis (CMD) monitoring, and the microbiome.Recent FindingsLittle evidence exists to support differences in feeding practices among the neurocritical care population. New areas of interest with limited data include use of immunonutrition, pre/probiotics for microbiome manipulation, ketogenic diet, and use of CMD catheters for substrate utilization monitoring.SummaryAcute neurologic injury incites a cascade of adrenergic and neuroendocrine events resulting in a pro-inflammatory and hypercatabolic state, which is associated with an increase in morbidity and mortality. Nutritional support provides substrates to mitigate the damaging effects of hypermetabolism. Despite this practice, studies on feeding delivery outcomes remain inconsistent. Guidelines suggest use of early enteral nutrition using standard polymeric formulas. Population heterogeneity, variability in interventions, complexities of the metabolic and inflammatory responses, and paucity of nutrition research in patients requiring neurocritical care have led to controversies in the field. It is imperative that more pragmatic and reproducible research be conducted to better understand underlying pathophysiology and develop interventions that may improve outcomes.

Outcomes of Neonates Born to Mothers With Coronavirus Disease 2019 (COVID-19) — National Neonatology Forum (NNF) India COVID-19 Registry

BackgroundLimited evidence exists on perinatal transmission and outcomes of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection in neonates.ObjectiveTo describe clinical outcomes and risk factors for transmission in neonates born to mothers with perinatal SARS-CoV-2 infection.DesignProspective cohort of suspected and confirmed SARS-CoV-2 infected neonates entered in National Neonatology Forum (NNF) of India registry.SubjectsNeonates born to women with SARS-CoV-2 infection within two weeks before or two days after birth and neonates with SARS-CoV-2 infection.OutcomesIncidence and risk factors of perinatal transmission.ResultsAmong 1713 neonates, SARS-CoV-2 infection status was available for 1330 intramural and 104 extramural neonates. SARS-CoV-2 positivity was reported in 144 intramural and 39 extramural neonates. Perinatal transmission occurred in 106 (8%) and horizontal transmission in 21 (1.5%) intramural neonates. Neonates roomed-in with mother had higher transmission risk (RR1.16, 95% CI 1.1 to 2.4; P=0.01). No association was noted with the mode of delivery or type of feeding. The majority of neonates positive for SARS-CoV2 were asymptomatic. Intramural SARS-CoV-2 positive neonates were more likely to be symptomatic (RR 5, 95%CI 3.3 to 7.7; P<0.0001) and need resuscitation (RR 2, 95%CI 1.0 to 3.9; P=0.05) compared to SARS-CoV-2 negative neonates. Amongst symptomatic neonates, most morbidities were related to prematurity and perinatal events.ConclusionData from a large cohort suggests perinatal transmission of SARS-CoV-2 infection and increased morbidity in infected infants.

Modelling the transmission and vaccination strategy for porcine reproductive and respiratory syndrome virus.

Many aspects of the porcine reproductive and respiratory syndrome virus (PRRSV) between-farm transmission dynamics have been investigated, but uncertainty remains about the significance of farm type and different transmission routes on PRRSV spread. We developed a stochastic epidemiological model calibrated on weekly PRRSV outbreaks accounting for the population dynamics in different pig production phases, breeding herds, gilt development units, nurseries and finisher farms, of three hog producer companies. Our model accounted for indirect contacts by the close distance between farms (local transmission), between-farm animal movements (pig flow) and reinfection of sow farms (re-break). The fitted model was used to examine the effectiveness of vaccination strategies and complementary interventions such as enhanced PRRSV detection and vaccination delays and forecast the spatial distribution of PRRSV outbreak. The results of our analysis indicated that for sow farms, 59% of the simulated infections were related to local transmission (e.g. airborne, feed deliveries, shared equipment) whereas 36% and 5% were related to animal movements and re-break, respectively. For nursery farms, 80% of infections were related to animal movements and 20% to local transmission; while at finisher farms, it was split between local transmission and animal movements. Assuming that the current vaccines are 1% effective in mitigating between-farm PRRSV transmission, weaned pigs vaccination would reduce the incidence of PRRSV outbreaks by 3%, indeed under any scenario vaccination alone was insufficient for completely controlling PRRSV spread. Our results also showed that intensifying PRRSV detection and/or vaccination pigs at placement increased the effectiveness of all simulated vaccination strategies. Our model reproduced the incidence and PRRSV spatial distribution; therefore, this model could also be used to map current and future farms at-risk. Finally, this model could be a useful tool for veterinarians, allowing them to identify the effect of transmission routes and different vaccination interventions to control PRRSV spread.

Coeliac disease presenting atypically: A much wider spectrum.

Atypical coeliac disease in young children is frequently missed when it presents atypically as non-gastrointestinal presentations to different specialties. There was a greater delay (54months) in establishing the diagnosis in those with atypical coeliac disease (p < 0.001). No difference was observed in the mode of delivery or duration of breast feeding, but significant difference was observed between gestational age at birth (p < 0.001). Most cases showed stunted growth and underweight. Irritability, anaemia, rickets, dermatitis herpetiformis, alopecia and intussusception were other common predictors of atypical coeliac disease. Because of a myriad spectrum of non-gastrointestinal symptoms, at any age with diverse presentation, a high index of suspicion is therefore required.

Methionine precursor effects on lactation performance of dairy cows fed raw or heated soybeans

Two experiments were conducted to evaluate the effect of isopropyl ester of 2-hydroxy-4-(methylthio) butanoic acid (HMBi) on lactation performance of dairy cows. Experiment 1 evaluated the effect of HMBi in diets with 15.3% crude protein (CP) and with different proportions of rumen-degradable and undegradable protein. Variation in rumen-degradable and undegradable protein was achieved by replacing raw with heated soybeans. Experiment 2 was an on-farm trial to evaluate HMBi with a large number of observations and using a farm-formulated diet (17.2% CP). In experiment 1, 20 Holsteins at 100 ± 41 d in milk were allocated to 5 replicated 4 × 4 Latin squares with 21-d periods. Treatments were formed by a 2 × 2 factorial arrangement of raw or heated soybeans with or without HMBi. Paper capsules with HMBi were orally administered twice daily to each cow. Dosage of HMBi was 7.6 g of digestible Met/cow per day. There was no interaction between soybean type and HMBi. Heat-treated soybeans increased the yields of milk, protein, fat, and lactose, and reduced urea N in milk and plasma (PUN) compared with raw soybeans. Rumen microbial yield, dry matter intake (DMI), and the total-tract apparent digestibility of nutrients did not differ between soybean types. There was no evidence for HMBi-driven effects on DMI, milk and components yield, or diet digestibility. Urinary purine derivative excretion and PUN concentration were reduced in HMBi-fed cows compared with cows fed diets without HMBi. In experiment 2, 294 Holstein cows were blocked by parity and milk yield, and randomly assigned to HMBi (8.9 g of digestible Met/cow per day) or control. The final data set had 234 cows (215 ± 105 days in milk; 96 primiparous and 138 multiparous; 114 on control and 120 on HMBi) housed in 4 freestall groups (1 group/treatment per parity). The freestall group was the experimental unit for DMI, diet and orts composition, and feed availability. The HMBi supplement was top dressed for 28 d on the first daily meal of each cow, immediately after feed delivery of the same batch of feed to all 4 freestall groups (3 times per day). Sample collection and feed analysis occurred during the last 5 d. Spot urine samples and blood samples from each cow were obtained for analysis of the urinary allantoin to creatinine ratio and PUN. Feed availability, the contents of CP and neutral detergent fiber in diets and orts, and DMI did not differ. Cows fed with HMBi had greater milk protein yield and concentration compared with control and had no change in milk fat and lactose. Rumen microbial yield was greater and PUN was lower in HMBi-fed cows compared with control. In experiment 1, HMBi decreased rumen microbial yield and did not affect lactation performance, but it increased ruminal microbial yield and the secretion of milk protein in experiment 2. These results suggest that lactation response to HMBi may be partially mediated by ruminal events. Heated soybeans increased the efficiency of N utilization and the yields of milk, protein, fat, and lactose, but did not interact with HMBi supplementation.

Frequency of hypocalcemia in jaundiced term neonates under phototherapy.

Background: Jaundice is most frequent situations requiring medical attention in neonate (involvev 60% full-term infants and 80% preterm infants in the 1st week after birth). Neonatal jaundice is the most frequent cause for hospital admission in the first 2 weeks of life. Light therapy is one of ordinary approach to treat hyperbilirubinemi. Phototherapy plays a signifying part in treatment and prevention of hyperbilirubinemia. However, this treatment form may lead to development of some complications such as induction of hypocalcemia. Objective: The goal of research is to estimate the outcome of light therapy on serum calcium in neoborne with hyperbilirubinemia who undergo phtotherapy and to find the relation between effect of phototherapy on serum calcium and gender, mode of delivery and type of feeding. Methods: Across sectional study was conducted at neonatal care unit at AlZahraa teaching hospital from January 2017 to December 2017. This study was conducted on 62 neonates (37 male and 25 female) with neonatal hyperbilirubinemia admmited in newborn nursery of either gender managed by phototherapy entered in this study, calcium level evaluated before and 48 hours after light therapy for all neonate under phototherapy and the tow values were compared. Results: There was statistically important decline of serum calcium and bilirubin after phototherapy as compared with serum calcium and bilirubin levels before phototherapy in this study (P<0.001). Four neonates evolved hypocalcemia (sr.Ca<8 mg/dl) no one had symptoms. There was no expressive corporation between decline serum calcium level and gender, mode of delivery and type of feeding. Conclusion: There is significant decrease in serum calcium after light therapy but risk of hypocalcemia is low in healthy babies. No expressive corporation founds between decline in serum calcium and gender, mode of delivery and type of feeding.

Effect of totally replacing hay by wood chips and feed delivery system on performance, behavior and carcass traits of finishing steers

An experiment was conducted to evaluate wood chips as solely fiber source in high-concentrate diet and it system of delivery (hand-feeding vs self-feeder) in feedlot. Thirty-six steers (362±48.5 kg) blocked by bodyweight (BW) were randomly assigned to nine pens and three treatments: 1) 20% hay plus 80% commercial concentrate hand-fed; 2) 8% wood chips 92% commercial concentrate hand-fed (WCH-HF), and 3) 8% wood chip plus 92% commercial concentrate self-feed (WCH-SF). The experiment lasted 70-d. Wood chips replaced totally hay (Setaria italica) in diets which were formulated to contain similar concentration of N, energy and NDF and were offered as a total mixed ration. The animals were gradually introduced to their diets and then fed ad libitum. Body weight was recorded every 14 days. Dry matter intake (DMI) was measured daily on even weeks, and mean feed-to-gain (FG) ratio was calculated for the experimental period. Animal behavior was record during weeks 4 and 8, and physical effective fiber supply (peNDF) were estimated on weeks 5 and 9. Steers were all slaughtered on the same date, and then carcass traits were measured. The experiment was analyzed according to a randomized block design, with repeated measures. Fiber source and delivery system effects were tested through orthogonal contrasts. The replacement of GH with WCH did not affect (P>0.05) peNDF nor BW gain, but it did reduce DMI (P<0.01), improving FG (P<0.01). This change also increased resting time at the expense of ruminating activity. The replacement of HF with SF did not affect BW gain (P>0.05), but it did increase DMI (P<0.05) and FG value (P<0.01). Higher FG in SF could be related to the observed larger variation in DMI between weeks and between days (P<0.01) compared to a more stable intake pattern in HF. No differences due to fiber source or feed delivery system were observed in carcass weight (265.6±15.6 kg), back fat (11.3 ±2.1mm), or the rib-eye area (54.4 ±4.9 cm2). The inclusion up to 8% of wood chip in total replacing hay in finishing diets permit greater inclusion of concentrates increasing NEg and improving feed efficiency without detrimental effect on BW gain and carcass characteristics. Self-feeder can be an option to optimizing fed delivery in low-forage diets.

Gastroparesis in the Hospital Setting.

Gastroparesis (GP) is commonly seen in hospitalized patients. Refractory vomiting and related dehydration, electrolyte abnormalities, and malnutrition are indications for hospital admission. In addition, tube feeding intolerance is a common sign of gastric dysmotility in critically ill patients. The diagnosis and management of GP in the hospital setting can be quite challenging. Diagnostic tests are often deferred because of patient intolerance of the oral meal for standard scintigraphy or severity of the primary disease. The diagnosis of GP is often established on the basis of clinical scenario and risk factors for gastric motor dysfunction. Medical therapy in GP is directed toward controlling nausea and vomiting by prokinetic and antinausea medications and correcting nutrition risks or treating malnutrition with nutrition therapy. Enteral nutrition is the preferred nutrition intervention for patients with GP. Delayed gastric emptying in critically ill patients has a negative impact on the timely delivery of enteral feeding and meeting the energy and protein goals. Measures to improve gastric tolerance or provide feeding beyond the stomach are often needed, since early enteral nutrition has been an important target of therapy for critically ill patients. This review will address the current understanding of the mechanisms of GP and feeding intolerance in critical illness, diagnostic workup, drug therapies, and interventions to improve the provision of enteral nutrition in hospital settings when gastric dysmotility is present or suspected.

Barriers to the delivery of enteral nutrition in pediatric intensive care units: A national survey.

Background and AimAccording to previously reported studies in the literature, a significant number of patients do not receive enteral nutrition in pediatric intensive care unit (PICU) because of avoidable barriers. Optimal nutrition is a fundamental goal in PICU. This study aims to identify the barriers of enteral nutrition in PICU.Setting and DesignA cross-sectional study of the results of a 25-item questionnaire-based survey distributed during the Annual International Critical Care Conference by the Saudi Critical Care Society.Methods and materialA 7-point Likert-type scale was used to rank the participants’ responses, and the relative importance index (RII) approach was used to analyze the relative contribution of each indicator to its main theme.The factor and parallel analysis methods were used to assess the factorial and unidimensionality of the enteral feeding barriers scale.ResultsA total of 223 PICU healthcare workers from various intensive care settings responded to the survey. The top-three perceived barriers for commencing enteral feeding were due to the patient being hemodynamically unstable (M = 3.6 and SD = 1.70), delays and difficulties in obtaining small bowel access in patients not tolerating other types of enteral nutrition (M = 3.4 and SD = 1.52), or severe fluid restriction, particularly in postoperative cardiac surgery (M = 3.3 and SD = 1.59). The top perceived overall barriers to enteral feeding were the dietician-related issues (M = 3.3, SD = 1.32), barriers related to enteral feeding delivery (M = 3.16 and SD = 1.13), and medical practice-related (M = 3 and SD = 1.10) issues. The lowest reported overall barriers were the resource-related obstacles (M = 2.7 and SD = 1.26).ConclusionBeing hemodynamically unstable and other dietician-related reasons were the top overall barriers in commencing enteral feeding.

Feed intake and feeding behavior traits for gestating sows recorded using electronic sow feeders.

Electronic sow feeding (ESF) systems are used to control feed delivery to individual sows that are group-housed. Feeding levels for gestating sows are typically restricted to prevent excessive body weight gain. Any alteration of intake from the allocated feeding curve or unusual feeding behavior could indicate potential health issues. The objective of this study was to use data recorded by ESF to establish and characterize novel feed intake and feeding behavior traits and to estimate their heritabilities. Raw data were available from two farms with in-house manufactured (Farm A) or commercial (Farm B) ESF. The traits derived included feed intake, time spent eating, and rate of feed consumption, averaged across or within specific time periods of gestation. Additional phenotypes included average daily number of feeding events (AFE), along with the cumulative numbers of days where sows spent longer than 30 min in the ESF (ABOVE30), missed their daily intake (MISSF), or consumed below 1 kg of feed (BELOW1). The appetite of sows was represented by averages of score (APPETITE), a binary value for allocation eaten or not (DA_bin), or the standard deviation of the difference between feed intake and allocation (SDA-I). Gilts took longer to eat than sows (15.5 ± 0.13 vs. 14.1 ± 0.11 min/d) despite a lower feed allocation (2.13 ± 0.00 vs. 2.36 ± 0.01 kg/d). The lowest heritability estimates (below 0.10) occurred for feed intake traits, due to the restriction in feed allocation, although heritabilities were slightly higher for Farm B, with restriction in the eating time. The low heritability for AFE (0.05 ± 0.02) may have reflected the lack of recording of nonfeeding visits, but repeatability was moderate (0.26 ± 0.03, Farm A). Time-related traits were moderately to highly heritable and repeatable, demonstrating genetic variation between individuals in their feeding behaviors. Heritabilities for BELOW1 (Farm A: 0.16 ± 0.04 and Farm B: 0.15 ± 0.09) and SDA-I (Farm A: 0.17 ± 0.04 and Farm B: 0.10 ± 0.08) were similar across farms. In contrast, MISSF was moderately heritable in Farm A (0.19 ± 0.04) but lowly heritable in Farm B (0.05 ± 0.07). Heritabilities for DA_bin were dissimilar between farms (Farm A: 0.02 ± 0.02 and Farm B: 0.23 ± 0.10) despite similar incidence. Individual phenotypes constructed from ESF data could be useful for genetic evaluation purposes, but equivalent capabilities to generate phenotypes were not available for both ESF systems.

Design and development of an automatic vegetable transplanter using a novel rotating finger device with push-type mechanism for plug seedlings

ABSTRACT Manual vegetable transplanting is a time-consuming, labor-intensive, operation. The objective of the study was to design, develop, and evaluate an automatic vegetable transplanter (AVT) for plug seedlings of chili (Capsicum annuum L.). Metering mechanisms in an AVT are affected by the transmission system and changes in desired plant spacing. To overcome problems, a novel rotating finger device with a push-type mechanism was developed for automatic transplanting of vegetable plug seedlings. The AVT consists of a pair of L-shaped rotating fingers, feed roller unit, metering mechanism, and delivery unit. Clearance between the feed roller and fingers is adjustable. The average values of performance parameters: plant spacing (Ps), planting depth (Pd), mis-planting (Mp), multiple planting (Mt), seedling mortality (Sm), transplanting efficiency (Et), and field transplanting efficiency (Ef) were 599.8 mm, 46.4 mm, 4.9%, 1.1%, 0.9%, 92.6%, and 76.12%, respectively. Effective field capacity (Fc) with the transplanter was 0.093 ha∙h−1 and 0.027 ha∙h−1 with the manual method. The two-row AVT can be used with a small tractor and may make up for labor shortage during peak season.

248 Application of computer vision and data analytics strategies for prediction of carcass composition in live pigs

Abstract The measurement of carcass traits in live pigs, such as muscle depth (MD) and backfat thickness (BF), is a topic of great interest for breeding companies and production farms. Breeding companies currently measure MD and BF using medical imaging technologies such as ultrasound (US). However, US is costly, requires trained personnel, and involves direct interaction with the animals, which is an added stressor. An interesting alternative in this regard is to use computer vision techniques. Farmers would also take advantage of such an application as they would be able to better adjust feed composition and delivery. Therefore, the objectives of this study were: (1) to develop a computer vision system for prediction of MD and BF from 3D images of finishing pigs; (2) to compare the predictive ability of statistical (multiple linear regression, partial least squares) and machine learning (elastic networks and artificial neural networks) approaches using features extracted from the images against a deep learning (DL) approach that uses the raw image as input. A dataset containing 3D images and ultrasound measurements of 618 pigs with average body weight of 120 kg, MD of 65 mm, and BF of 6 mm was used in this study. To assess the predictive performance of the different strategies, a 5-fold cross-validation approach was used. The DL achieved the best predictive performance for both traits, with predictive mean absolute scaled error (MASE) of 5.10% and 13.62%, root-mean-square error (RMSE) of 4.35mm and 1.10mm, and R2 of 0.51 and 0.45, for MD and BF respectively. In conclusion, it was demonstrated that it is possible to satisfactorily predict MD and BF using 3D images that were autonomously collected in farm conditions. Also, the best predictive quality was achieved by a DL approach, simplifying the data workflow as it uses raw 3D images as inputs.

6 Feed intake variability and performance implications of adjusting for dry matter content of cattle feedlot feed ingredients exposed to the elements

Abstract Objectives of this study were: 1) validate on-farm dry matter (DM) testing methods, and 2) determine how as-fed dietary composition adjustment to respond to DM content changes affected performance. One-hundred fifty-one crossbred steers (n = 85; 404 kg initial BW) and heifers (n = 66; 384 kg initial BW) were allocated randomly (4 to 6 hd/pen), within truck load and sex, to one of two 15-pen rows in a deep-bedded confinement barn. Treatments included control (n = 15 pens), where diets were only modified to account for changes in ingredient DM every 28 d or adjusted (ADJ; n = 15 pens), in which diets were modified daily to account for changes in ingredient DM. Target composition of diets was (DM basis) hay (3.73%), corn silage (CS; 8.28%), high moisture corn (HMC; 50.86%), dry distillers grains with solubles (DDGS; 11.83%), dry rolled corn (DRC; 20.07%), and a liquid supplement (5.23%). Cattle were fed for 84 d. Dry matter content of hay was determined daily using a microwave oven and that of CS and HMC were determined using a forced-air dryer every other day upon removal from bunker silos; these methods were validated against DM determination using a forced-air oven set at 105 °C. Hay or corn silage DM measured indirectly was similar (P &amp;gt; 0.10) to that measured using a forced-air oven at 105 °C. Adjusting as-fed dietary composition daily to compensate for changes in ingredient DM had no effect on DMI, ADG, feed conversion or final BW. Within-pen feed delivery residual variance tended to be greater (P = 0.06) for pens managed under ADJ. Within-pen and between-treatment residual DMI variance was not different (P &amp;gt; 0.10). Under the conditions of this study, exposure to the elements did not precipitate in large changes in diet DM composition or content. This resulted in similar performance response whether dietary as-fed composition was adjusted or not.

187 Effects of energy supplementation during early gestation in beef heifers on body weight, concentrations of IGF-1, and calf characteristics

Abstract Objectives were to evaluate effects of early gestation energy supplementation on heifer body weight (BW), IGF-1 concentrations, and calf characteristics. One-hundred Angus-based heifers (initial BW = 371.1 ± 3.9 kg) were estrous synchronized, bred to female-sexed semen, then randomly assigned to either a basal diet to achieve 0.20 kg/d (CON, n = 50) or a basal diet plus supplemental energy to achieve 0.75 kg/d gain (SUPP, n = 50) for 84 d. The CON diet consisted of 37% corn silage, 53% prairie hay, and 10% distillers dried grain with solubles (DDGS). The SUPP diet was 29% corn silage, 41% prairie hay, 5% DDGS, and 25% corn/PurinaAccuration Range Supplement 33 blend. Heifers were individually fed via Insentec feeders (Insentec Marknesse, The Netherlands), with bi-weekly feed delivery adjustments to achieve targeted gains. After d 84, heifers were managed as a single group on pasture, then in a dry lot until parturition. A total of 46 heifers gestated female pregnancies to term (n = 23 CON and n = 23 SUPP). Body weights and blood samples were collected on d 0, 42, 84, 162, 234, 262, and at parturition. By design, SUPP heifers were 55.4 kg heavier (P &amp;lt; 0.0001) than CON at d 84. Weight divergence remained throughout gestation, with SUPP heifers being 41.5 kg heavier at parturition (P &amp;lt; 0.0001). For SUPP, IGF-1 concentrations were greater throughout gestation (P = 0.003). Fetal size, as measured by ultrasound, was not affected by treatment at d 42 (P = 0.50), 63 (P = 0.35), or 84 (P = 0.20); however, calves from SUPP dams were 2.1 kg heavier (P = 0.03) and had larger chest circumference (P = 0.05) at birth compared with CON. Early gestation nutrition impacted heifer BW and IGF-1 concentrations throughout gestation, and clearly impacted in utero fetal growth.

The effects of social environment on standing behavior and the development of claw horn lesions

The primary aim of this prospective experimental study was to evaluate how the social environment after calving influenced standing behavior in primiparous cows. At calving, primiparous cows were mixed with familiar peers in a low-stocked pen (≤33% stocking density; n = 22) or mixed with unknown older cows at 100% stocking density (n = 20). All study cows were mixed with older cows 3 wk after calving. Time spent standing and perching (standing with only the front feet in the stall) were measured d 1 to 3 after calving using 5-min scan sampling. To evaluate if the low-stocked treatment constituted a low-stress social environment, agonistic interactions at the feed barrier were measured for 90 min following feed delivery for a subsample of cows in both treatments (12 cows/treatment). The daily behavioral time budget, including the 90 min following milking, was examined for this subset of cows. A secondary aim was to assess if the social environment after calving was related to the risk of developing claw horn lesions later in lactation. Sole and white line lesions were recorded at wk 6 and 12 after calving, and cows were categorized as either having or not having at least 1 hemorrhage of severity ≥3 (scale 1 to 5) for each lesion type and assessment. Prolonged standing after regrouping was not observed, and we found no differences in standing time and time spent perching between treatments. Agonistic behaviors directed toward the focal cows occurred less frequently in the low-stocked pen compared with the control. The number and severity of sole and white line lesions increased after calving. At wk 6 postpartum there was a numeric (but not statistically significant) difference between treatments in the proportion of primiparous cows that had white line hemorrhages of severity score ≥3 (low-stress social environment: 20% vs. control: 50%). In conclusion, under the conditions of this study the social environment did not influence standing behavior, but did affect agonistic interactions and may have influenced the risk of claw horn lesions in the weeks following calving. Further studies should evaluate the relationship between the social environment and claw health.

169 The effects of once or twice daily feed delivery on the finishing performance and carcass characteristics of feedlot steers

Abstract Yearling Angus steers (n = 64; arrival BW = 322 ± 44 kg) from a single ranch were used to determine the effects of delivering feed once (1X) or twice (2X) per day on finishing performance and carcass characteristics. Steers were blocked by BW and randomly assigned to pens (4.57 × 15.24 m; 4 steers per pen). Pens were randomly assigned to 1 of the 2 experimental treatments (1X or 2X). All steers were fed a common dry-rolled corn finishing ration for 141 d. Feed was delivered to steers in fence-line concrete bunks (4.57 m in length; 1.14 m per steer) with the only difference between experimental treatments being the frequency of feed delivery. The 1X steers received 100% of the daily feed call at 0930 h, while the 2X steers received 50% of the daily feed call at both 0930 and 1400 h. Pen served as the experimental unit, and all steers were harvested on d 142. There were no differences in final BW (P = 0.95) or overall ADG (P = 0.94) between experimental treatments; however, overall DMI was greater for the 1X steers (P &amp;lt; 0.01). The difference in DMI combined with no difference in ADG resulted in a 4% improvement in overall G:F for the 2X steers (P = 0.03). There were no differences between the experimental treatments for any carcass characteristics (P ≥ 0.28). While this experiment was conducted in a small pen research setting, the results suggest that the frequency of feed delivery impacts the intake and feed efficiency of feedlot steers. Consideration should be given to the impacts of feed delivery on feedlot logistics and batching in commercial settings.

Assessing response to dry-off in dairy cows kept outdoors using spontaneous behaviours and infrared thermography-a pilot study.

We used spontaneous behaviours to assess response to dry-off involving abrupt dietary and milking frequency changes, followed by regrouping, after the last milking in 15 clinically healthy Holstein-Frisian cows kept outdoors. Moreover, we explored the potential of infrared thermography to detect eye temperature variations possibly induced by dry-off. On days - 1, 0, 1 and 2 relative to dry-off, we recorded whether cows vocalised during feed delivery; ate fresh feed within 5min; and mean maximum eye temperature at approximately 1h after feed delivery. On days 1 and 2, cows were more likely to eat fresh feed compared to days - 1 and 0. No difference in likelihood of vocalising was found. Compared to day - 1, eye temperature was substantially higher on days 0 and 2. Collectively, the results suggest that cows responded, both behaviourally and physiologically, to the abrupt dry-off management. The interpretation of the current findings deserves further investigation using larger sample sizes, more controlled environments and further behavioural, physiological, cognitive and clinical measures.

Effect of hyperketonemia on the diurnal patterns of energy-related blood metabolites in early-lactation dairy cows

Most dairy cows experience a period of energy deficit in early lactation, resulting in increased plasma concentrations of nonesterified fatty acids (NEFA) and β-hydroxybutyrate (BHB). Our objectives were to determine (1) the diurnal variation in plasma BHB and NEFA, (2) the correlation between plasma NEFA and BHB when accounting for diurnal changes, and (3) the effect of hyperketonemia (HYK) on the diurnal pattern of blood metabolites. Jugular catheters were placed in 28 multiparous Holstein cows between 3 and 9 days in milk, and blood samples were collected every 2 h for 96 h. Cows were retrospectively classified as HYK positive (HYK; n = 13) if they had plasma BHB concentrations ≥1.2 mmol/L for ≥3 study days, or HYK negative (non-HYK; n = 15) if they had plasma BHB concentrations ≥1.2 mmol/L for ≤2 study days. Generalized linear mixed models were used to analyze concentrations of analytes over time and differences in metabolites between HYK groups. The correlation between total plasma NEFA and BHB was analyzed by calculating the area under the curve for plasma NEFA and BHB for all cows. Plasma NEFA reached a peak approximately 2 h before morning feed delivery, falling to a nadir in the late evening. Plasma BHB was at a nadir at the time of morning feed delivery, peaking 4 h later. We observed a strong positive correlation between daily plasma NEFA and BHB. Additionally, HYK cows had greater concentrations of plasma NEFA and BHB than non-HYK cows. The HYK cows also experienced a greater magnitude of change in BHB throughout the day than the non-HYK cows. Our results suggest that the time relative to feeding should be considered when analyzing plasma metabolites, as classification of energy status may change throughout a day.

Feed intolerance and postpyloric feeding in the critically ill child

: Feeding intolerance (FI) is a common problem in critically ill children that results in feed interruptions impacting heavily on outcome. The lack of consistent and validated definition for FI makes difficult to know the real prevalence of this problem in these patients and precludes obtaining conclusive results on predictors and outcomes. Gastric dysmotility (GD) is the principal mechanism underlying FI. The aetiology of GD is largely unknown but many factors (vasoactive drugs, sedatives, opioids, muscle relaxation drugs, hypoperfusion) may be involved in its appearance. Future research must focus on clarifying the potential mechanisms of FI during critical illness as well as finding a proper and validate definition of FI. Several actions are used in clinical practice to reduce FI in critically ill children as prokinetic agents, change from polymeric to semi-elemental formulation and change of feed delivery method from intermittent bolus to continuous feeding. However, the evidence does not support the routine use of these methods to manage FI. Transpyloric enteral nutrition (TEN) is another option to manage FI in sick children as it has proven to be safe and well tolerated with few complications in these patients. TEN promote early nutrition and reduce the volume of gastric residues and the number of enteral nutrition interruptions increasing energy intake. Children with shock, acute kidney injury (AKI) and in the recovery of cardiac surgery may benefit from this technique. However, feeding tube insertion is difficult and it is not exempt of problems. Staff must be trained to detect and decrease complications associated with its utilization.

Effects of feeding frequency and oil supplementation on feeding behavior, ruminal fermentation, digestibility, blood metabolites, and milk performance in late-lactation cows fed a high-forage diet

Many dairy producers are keen to feed low-producing late-lactation cows only once per day (1×) to reduce production costs. This study examined effects of feeding frequency (FF: thrice versus once daily) on behavioral patterns, ruminal fermentation, and milk production performance of cows and supplementation of yellow grease oil (YO) rich in 18:2n-6 as a potential strategy to alleviate the possible negative effects of 1× daily feeding. Twenty-four late-lactation Holstein cows (215 ± 53.8 DIM) housed in tiestalls were assigned to 4 treatments according to a 2 × 2 factorial arrangement with 2 FF [3 times daily (3×) at 0800, 1400, and 2000 h; or 1× at 0800 h] and 2 high-forage total mixed rations (TMR), without (CON) or with 25 g/kg of dry matter of YO (YGO), in a randomized complete block design. Treatments were applied for 21 d. Feeding behavior was recorded every 5 min over a 24-h period on d 19. Fresh TMR and orts were sampled (d 15 to 21) and separated using a 3-screen (19, 8, and 1.18 mm) Penn State Particle Separator for sorting activity. Ruminal fluid samples were collected using oral stomach tubing on d 21. Cows on 1×-CON spent more time eating during the first 6 h after feeding at 0800 h than did cows on 3×-CON or 1×-YGO. Decreasing FF increased meal length and tended to increase meal size for CON cows, but supplementing YO increased meal bouts and reduced meal length and size for cows fed 1×. Cows on 1×-CON had the greatest ruminating time between 2000 and 0800 h compared with other treatments. Total and daytime distribution of lying time did not vary by treatments. Sorting activity was higher for cows fed frequently, and the extent of sorting was increased by oil supplementation. In the morning ruminal fluid samples, pH was not different among treatments, but in the evening samples 1× daily feeding reduced ruminal pH compared with 3×. In the morning and evening samples, ratios of acetate to propionate were the lowest for 1×-CON cows compared with other treatments. Dry matter intake and milk yield were similar among the groups. Milk fat content and yield decreased with 1×-CON treatment, but supplementing YO numerically increased milk fat for cows fed 1×. These results suggest that decreasing FF from 3× to 1× daily increases meal length, particularly after feed delivery, in cows fed high-forage diets; but supplementation of plant oil changes feeding patterns and may improve ruminal pH and milk fat in cows fed once a day.