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The objective of this study was to determine the effect of limiting forage provision in pre-weaned calves on ruminal pH and short chain fatty acid (SCFA) transport capacity during the pre-weaning period. Twelve Jersey bull calves (age = 1.9 ± 0.8 d) were housed individually on sand. All calves were fed milk replacer at 1,200 g/d and texturized grain-based starter ad libitum from birth. Calves were randomly assigned one of two treatments: ad libitum forage ( ALF ) or limited forage provision, where forage was limited to 90 g/d as-fed ( LFP ). Individual feed intake was recorded daily, calf weights, and jugular blood samples were collected weekly. Once calves consumed 680 g/d of calf starter, ruminal pH was measured for seven days after which calves were humanely killed and rumen fluid sampled. During the pre-weaning period, starter intake, feed efficiency, plasma glucose and β-hydroxybutyrate (BHB) concentration, SCFA concentration, average daily gain, and body weight were not different between treatments. Forage intake for ALF calves was greater than LFP beginning at wk 9 (255 ± 34 vs. 71 ± 40 g/d, respectively). Compared to ALF, LFP decreased mean ruminal pH (6.38 ± 0.16 vs. 5.98 ± 0.23) and duration of time where rumen pH was below 5.8 (796 ± 145 vs. 261 ± 133 min/d). Epithelial markers of SCFA transport and cell homeostasis (MCT1, NBC1, NHE3) were not affected by treatment. In conclusion, incidence of sub-acute ruminal acidosis in limited forage-fed calves did not have the same effects on intake and nutrient transporters seen in adult cows., Competing Interests: The authors declare that they have no known competing interests., (© 2024 The Authors. Published by Elsevier Ltd.)

This study examined the effects of changes in rumen fermentation during the weaning transition on abundance of transporters involved in volatile fatty acid (VFA) absorption or intracellular pH homeostasis. Holstein bull calves (n = 27) were assigned to 1 of 3 treatment groups in a randomized, complete block design: 2 preweaning groups [animals fed milk only (PRE-M) or milk, calf starter, and hay (PRE-S)] and 1 postweaning group (animals fed milk, starter, and hay with a 2-wk weaning transition; POST-S). Calves were euthanized at 42 d of age (PRE-M and PRE-S) or at 63 d of age (POST-S), and rumen epithelium and rumen fluid samples were collected. Rumen fluid was analyzed for VFA concentration, and rumen epithelium was analyzed for the abundance of VFA transporter monocarboxylate transporter isoform 1 (MCT1) and the intracellular pH regulators sodium bicarbonate co-transporter 1 (NBC1) and sodium-proton exchanger 3 (NHE3) protein. Preweaning, total VFA concentrations tended to increase and NBC1 abundance increased with starter intake. Between pre- and postweaning, total VFA concentrations increased but NHE3 protein abundance decreased. In calves, rumen epithelial development during the weaning transition appears to show more pronounced changes in intracellular pH homeostasis than in VFA transport capacity., (© 2021.)

The objectives of this study were to determine the effects of the weaning transition and supplemental rumen-protected butyrate on subacute ruminal acidosis, feed intake, and growth parameters. Holstein bull calves (n = 36; age = 10.7 ± 4.1 d; ± standard deviation) were assigned to 1 of 4 treatment groups: 2 preweaning groups, animals fed milk replacer only (PRE-M) and those fed milk replacer, calf starter, and hay (PRE-S); and 2 postweaning groups, animals fed milk replacer, calf starter, and hay without supplemental rumen-protected butyrate (POST-S) or with supplemental rumen-protected butyrate at a rate of 1% wt/wt during the 2-wk weaning transition (POST-B). Milk replacer was provided at 1,200 g/d; starter, water, and hay were provided ad libitum. Weaning took place over 14 d by reducing milk replacer provision to 900 g/d in wk 7, 600 g/d in wk 8, and 0 g/d in wk 9. Rumen pH was measured continuously for 7 d during wk 6 for PRE-S and PRE-M and during wk 9 for POST-S and POST-B. After rumen pH was measured for 7 d, calves were euthanized, and rumen fluid was sampled and analyzed for volatile fatty acid (VFA) profile. Individual feed intake was recorded daily, whereas, weekly, body weights were recorded, and blood samples were collected. Compared with PRE-M, PRE-S calves tended to have a greater total VFA concentration (35.60 ± 11.4 vs. 11.90 ± 11.8 mM) but mean rumen pH was unaffected (6.25 ± 0.22 vs. 6.17 ± 0.21, respectively). Between PRE-S (wk 6) and POST-S (wk 9), calf starter intake increased (250 ± 219 vs. 2,239 ± 219 g/d), total VFA concentrations increased (35.6 ± 11.4 vs. 154.4 ± 11.8 mM), but mean rumen pH was unaffected (6.25 ± 0.22 vs. 6.40 ± 0.22, respectively). Compared with POST-S, POST-B calves had greater starter intake in wk 7, 8, and 9, but POST-B tended to have lower total VFA concentration (131.0 ± 11.8 vs. 154.4 ± 11.8 mM) and lower mean ruminal pH (5.83 ± 0.21 vs. 6.40 ± 0.22). In conclusion, the weaning transition does not appear to affect rumen pH and VFA profile, but supplementing rumen-protected butyrate during the weaning transition increased starter intake and average daily gain. Further, these data suggest that the ability of the rumen to manage rumen pH changes fundamentally postweaning. Why weaned calves with lower rumen pH can achieve higher calf starter intakes is unclear; these data suggest the effect of rumen pH on feed intake differs between calves and cows., (Copyright © 2019 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.)

The potential adverse effects on the neonatal/pediatric population of administering concentrated intravenous medications are a concern. After an adult minibag was successfully converted to a syringe pump system, a similar system for neonates and children was developed. Additional factors considered with this conversion included: osmolarity, fluid volumes, and i.v. administration procedures. Charts that provided information on appropriate final concentrations of commonly used drugs were developed for nursing and pharmacy staffs. Inservice education was given to ensure understanding and compliance with the charts as well as the procedures developed for this delivery system (such as i.v. line setup, flushing procedures, and tubing changes). When this system was implemented, aminoglycosides were administered in a uniform manner. Previously, each area had its own method of aminoglycoside administration, which was not conducive to reliable therapeutic drug monitoring. Significant improvements in patient care, drug waste, and therapeutic drug monitoring resulted from using the pediatric syringe pump delivery system.

Modern whole-body dosimeters are often required to accurately measure the absorbed dose in a wide range of radiation fields. While programs are commonly developed around the fields tested as part of the National Voluntary Accreditation Program (NVLAP), the actual fields of application may be significantly different. Dose algorithms designed to meet the NVLAP standard, which emphasizes photons and high-energy beta radiation, may not be capable of the beta-energy discrimination necessary for accurate assessment of absorbed dose in the work environment. To address this problem, some processors use one algorithm for NVLAP testing and one or more different algorithms for the work environments. After several years of experience with a multiple algorithm approach, the Dosimetry Services Group of Yankee Atomic Electric Company (YAEC) developed a one-algorithm system for use with a four-element TLD badge using Li2B4O7 and CaSO4 phosphors. The design of the dosimeter allows the measurement of the effective energies of both photon and beta components of the radiation field, resulting in excellent mixed-field capability. The algorithm was successfully tested in all of the NVLAP photon and beta fields, as well as several non-NVLAP fields representative of the work environment. The work environment fields, including low- and medium-energy beta radiation and mixed fields of low-energy photons and beta particles, are often more demanding than the NVLAP fields. This paper discusses the development of the algorithm as well as some results of the system testing including: mixed-field irradiations, angular response, and a unique test to demonstrate the stability of the algorithm. An analysis of the uncertainty of the reported doses under various irradiation conditions is also presented.