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Four years of feedlot performance and carcass characteristics were pooled on spring-(SPRING) and fall-(FALL) born steers (n=460) into a mixed model to evaluate the effects of calving season, sire breed (Angus [AN], Charolais [CHAR] or Hereford [HER]) and their interaction on feedlot performance and carcass traits. Initial and final BW, DOF, ADG, DMI, and G:F were evaluated as performance measures and HCW, YG, FT, REA, and MS were collected at harvest. There was no season by breed interaction for entry or final BW (P >0.05). SPRING steers (400.2 kg, 686.4 kg) weighed more than FALL (350.9 kg, 668.3 kg) upon entering and leaving the feedyard (P< 0.001). CHAR weighed 14.3 kg less than AN upon feedlot entry (P=0.01) although final BW did not differ by breed (P >0.05). SPRING steers (21.8 kg/d) consumed more feed than FALL steers (18.8 kg/d; P=0.002), but there was no difference in gain:feed due to calving season nor sire breed (P=0.575). A calving season by sire breed interaction was present for ADG and DOF (P=0.014). FALL AN (1.70 kg/d) and FALL HER (1.80 kg/d) gained more than FALL CHAR (1.55 kg/d;P< 0.001) and FALL AN were fed over a shorter period than FALL CHAR and FALL HER (P=0.006). However, average daily gain of SPRING calves did not differ by breed (P >0.05). There was a tendency for FALL (400.9 kg) steers to have lighter carcasses than SPRING steers (407.9 kg; P=0.068). HER carcasses were 18.0 kg heavier than AN carcasses (P< 0.001), but did not differ from CHAR (P=0.13). CHAR had larger REA (93.5 cm2) than both AN (87.7 cm2) and HER steers (88.5 cm2;P=0.001). Fall-born steers had less YG than spring-born steers (P< 0.042). Feedlot performance was generally less for fall-born steers finished during the winter months. Under these conditions, numerous performance and carcass traits were influenced by the interaction of breed and season. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the relationship between beef heifer feed efficiency and subsequent greenhouse gas emissions using an unprocessed hay diet. Fifty-four Angus and Angus Herford cross heifers were subject to a 71-day hay intake test using individual intake technology (C-Lock Inc., Rapid City, SD) with a stocking rate of 3.6 heifers per feeder. Heifers were blocked by BW into 2 drylot pens (HEAVY, n=21; LIGHT, n=33) at the Oklahoma State University Range Cow Research Center located near Stillwater, OK. Throughout the study, heifers were fed a long-stem, unprocessed, grass hay diet (10.8% CP, 2.0 Mcal ME, and 56% TDN) with 21-d adaptation. A subset of 39 heifers were used for the collection of gas flux data using an open-circuit, portable, gas-quantification system (GreenFeed, C-Lock Inc., Rapid City, SD) to measure (means±SD) oxygen consumption (3,118±330.9 g/d), carbon dioxide production (4,664±467.9 g/d), and methane production (169±23.4 g/d). Phenotypic measures (means±SD) for dry matter intake (DMI), average daily gain (ADG), average body weight (BW), and residual feed intake (RFI) were 6.75±1.12 kg, 0.15±0.2 kg, 312.7±30.5 kg, and 0.08±0.84 kg, respectively. Predicted DMI was calculated using a multiple regression equation (-3.11 + 0.13*BW0.75+0.76*ADG; P< 0.05; R2=0.43) in R. To further evaluate forage efficiency, heifers were segregated by 0.5 SD into three RFI categories of efficient (n=13), average (n=31), and inefficient (n=10) resulting in means of 5.8, 6.76, and 7.94 kg DMI and 0.16, 0.16, and 0.15 kg ADG, respectively. There was no significant difference (p< 0.05) between RFI categories for ADG, CO2, CH4, and O2. Phenotypic correlations of DMI with CO2, CH4, and O2 were 0.59, 0.45, and 0.61, respectively. Efficient heifers consumed 21% less forage compared with inefficient heifers, suggesting that improvement in forage utilization can be achieved when efficiency is evaluated using an unprocessed grass hay diet. [ABSTRACT FROM AUTHOR]

This study's objective was to determine the relationship between retained energy, lactation maintenance energy requirement (MER), and dry period voluntary feed intake (VOL) in beef cows. Twenty-four mature fallcalving Angus cows were used in an 82-d study during lactation to establish maintenance energy requirements followed by a voluntary feed intake study after weaning. During the lactation MER experiment, cows were housed in 2 drylot pens and limit-fed a mixed hay/concentrate diet (17.8% CP, 2.6 Mcal/kg ME, DM basis) individually once per d in a stall barn. Cows were adapted to the diet and feeding management for the first 16 d. Subsequently, cows were weighed and feed allowance adjusted at 14-d intervals to achieve BW and BCS stasis. Milk yield and composition were determined on d - 10, 49, and 77 using a milking machine. Retained energy was calculated as average daily maternal tissue energy change plus average daily milk energy yield. During the post-weaning VOL experiment, cows were provided ad libitum access to a grass hay diet for 41 d (8.15% CP, 1.8 Mcal/kg ME, DM basis) using five individual feed intake monitoring units (SmartFeed, C-Lock, Inc). Each one unit increase in metabolizable energy intake, kcal/kg BW0.75 was associated with a 0.86 ± 0.28 kcal/kg BW0.75 increase in total retained energy (P = 0.005). Using this partial efficiency coefficient, ME required for maintenance declined by 0.80 ± 0.11 kcal ME/kg BW0.75 for each additional kcal net energy retained/kg BW0.75 (P < 0.0001). There was no relationship between lactation-period retained energy and post-weaning VOL forage dry matter intake. The present study results contradict previous reports suggesting that maintenance requirements increase with increasing productivity. [ABSTRACT FROM AUTHOR]

Background: Cancer-related pain is a complex multidimensional experience that affects all aspects of life. To support those impacted by cancer-related pain it is essential that health professionals have adequate knowledge in its assessment and management., Aims: To explore the knowledge of health professionals regarding cancer-related pain., Methods: A scoping review methodology was used to systematically search the literature published between 2010 and 2020. Databases CINAHL, Medline and PsycINFO were searched using terms 'cancer pain', 'healthcare professional', 'knowledge', 'attitudes' and 'barriers'., Findings: The search identified 38 articles. They focused on nursing knowledge with minimal involvement of allied health professionals. Knowledge levels were variable with the majority demonstrating poor knowledge. Common knowledge gaps included around fear of addiction, principles of cancer-related pain assessment and management, and interventional techniques., Conclusion: Knowledge of cancer-related pain is variable with several knowledge gaps. More work is needed to ensure health professionals have adequate knowledge regarding the complexity of cancer-related pain.

Purpose of Review: The formation of a pre-metastatic niche (PMN), in which primary cancer cells prime the distant site to be favorable to their engraftment and survival, may help explain the strong osteotropism observed in multiple cancers, such as breast and prostate. PMN formation, which includes extracellular matrix remodeling, increased angiogenesis and vascular permeability, enhanced bone marrow-derived cell recruitment and immune suppression, has mostly been described in soft tissues. In this review, we summarize current literature of PMN formation in bone. We also present evidence of a potential role for osteocytes to be the primary mediators of PMN development., Recent Findings: Osteocytes regulate the bone microenvironment in myriad ways beyond canonical bone tissue remodeling, including changes that contribute to PMN formation. Perilacunar tissue remodeling, which has been observed in both bone and non-bone metastatic cancers, is a potential mechanism by which osteocyte-cancer cell signaling stimulates changes to the bone microenvironment. Osteocytes also protect against endothelial permeability, including that induced by cancer cells, in a loading-mediated process. Finally, osteocytes are potent regulators of cells within the bone marrow, including progenitors and immune cells, and might be involved in this aspect of PMN formation. Osteocytes should be examined for their role in PMN formation., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Survival of the African trypanosome within its mammalian hosts, and hence transmission between hosts, relies upon antigenic variation, where stochastic changes in the composition of their protective variant-surface glycoprotein (VSG) coat thwart effective removal of the pathogen by adaptive immunity. Antigenic variation has evolved remarkable mechanistic complexity in Trypanosoma brucei, with switching of the VSG coat executed by either transcriptional or recombination reactions. In the former, a single T. brucei cell selectively transcribes one telomeric VSG transcription site, termed the expression site (ES), from a pool of around 15. Silencing of the active ES and activation of one previously silent ES can lead to a co-ordinated VSG coat switch. Outside the ESs, the T. brucei genome contains an enormous archive of silent VSG genes and pseudogenes, which can be recombined into the ES to execute a coat switch. Most such recombination involves gene conversion, including copying of a complete VSG and more complex reactions where novel 'mosaic' VSGs are formed as patchworks of sequences from several silent (pseudo)genes. Understanding of the cellular machinery that directs transcriptional and recombination VSG switching is growing rapidly and the emerging picture is of the use of proteins, complexes and pathways that are not limited to trypanosomes, but are shared across the wider grouping of kinetoplastids and beyond, suggesting co-option of widely used, core cellular reactions. We will review what is known about the machinery of antigenic variation and discuss if there remains the possibility of trypanosome adaptations, or even trypanosome-specific machineries, that might offer opportunities to impair this crucial parasite-survival process., (Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Human African trypanosomiasis, or sleeping sickness, is caused by the protozoan parasite Trypanosoma brucei and induces profound reactivity of glial cells and neuroinflammation when the parasites colonise the central nervous system. However, the transcriptional and functional responses of the brain to chronic T. brucei infection remain poorly understood. By integrating single cell and spatial transcriptomics of the mouse brain, we identify that glial responses triggered by infection are readily detected in the proximity to the circumventricular organs, including the lateral and 3 rd ventricle. This coincides with the spatial localisation of both slender and stumpy forms of T. brucei. Furthermore, in silico predictions and functional validations led us to identify a previously unknown crosstalk between homeostatic microglia and Cd138 + plasma cells mediated by IL-10 and B cell activating factor (BAFF) signalling. This study provides important insights and resources to improve understanding of the molecular and cellular responses in the brain during infection with African trypanosomes., (© 2022. The Author(s).)

Developmental steps in the trypanosome life-cycle involve transition between replicative and non-replicative forms specialised for survival in, and transmission between, mammalian and tsetse fly hosts. Here, using oligopeptide-induced differentiation in vitro, we model the progressive development of replicative 'slender' to transmissible 'stumpy' bloodstream form Trypanosoma brucei and capture the transcriptomes of 8,599 parasites using single cell transcriptomics (scRNA-seq). Using this framework, we detail the relative order of biological events during asynchronous development, profile dynamic gene expression patterns and identify putative regulators. We additionally map the cell cycle of proliferating parasites and position stumpy cell-cycle exit at early G1 before progression to a distinct G0 state. A null mutant for one transiently elevated developmental regulator, ZC3H20 is further analysed by scRNA-seq, identifying its point of failure in the developmental atlas. This approach provides a paradigm for the dissection of differentiation events in parasites, relevant to diverse transitions in pathogen biology., (© 2021. The Author(s).)

Understanding the rate and patterns of genome variation is becoming ever more amenable to whole-genome analysis through advances in DNA sequencing, which may, at least in some circumstances, have supplanted more localized analyses by cellular and genetic approaches. Whole-genome analyses can utilize both short- and long-read sequence technologies. Here we describe how sequence generated by these approaches has been used in trypanosomatids to examine DNA replication dynamics, the accumulation of modified histone H2A due to genome damage, and evaluation of genome variation, focusing on ploidy change.