Scholarly Works, School of Animal Sciences

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Effects of subclinical Theileria orientalis Ikeda genotype infection on average daily gain ratios and a satisfactory rating in the breeding soundness exam in bull test stations in Virginia
Guynn, Sierra R.; Currin, John F.; Todd, S. Michelle; Greiner, Scott P.; Lahmers, Kevin K. (Texas A&M University Libraries, 2023-07-17)
Theileria orientalis Ikeda genotype is a tick borne hemoprotozoan that typically causes economic losses in dairy and beef cattle in Australia, New Zealand and Japan. Acute clinical infections from T. orientalis Ikeda include anemia, icterus, ill-thrift and death. The acute phase of the infection has been associated with decreased libido in dairy bulls, decreased live weight gain in beef bulls and increased mortality in naïve adults and calves. A sequela to acute infections within a herd is persistent subclinical infections, which have been associated with decreased mean daily gain in suckling beef calves. In late 2017, T. orientalis Ikeda was detected in beef cattle from multiple counties in Virginia and was associated with anemia, weakness, late term abortions and death. As of 2022, T. orientalis Ikeda has been identified in beef cattle in 31 of 95 Virginia counties. Beef production, typically in naturally bred cow-calf operations, is the second largest agricultural commodity in Virginia. Central bull testing programs for performance evaluation and marketing of beef bulls has existed for over 60 years in Virginia. T. orientalis Ikeda was first detected at the Southwest bull test station in 2020 when screened at conclusion of the test. The objective of this study was to determine if subclinical infection with T. orientalis Ikeda affected the average daily gain (ADG) ratios of all bulls on test and the achievement of a satisfactory rating of the breeding soundness exam (BSE) for senior bulls.
Theileria orientalis Ikeda infection does not negatively impact growth performance or breeding soundness exam results in young beef bulls at bull test stations
Guynn, Sierra R.; Greiner, Scott P.; Currin, John F.; Todd, S. Michelle; Assenga, Alphonce; Hungerford, Laura L.; Lahmers, Kevin K. (Frontiers, 2024-07-18)
Introduction: Theileria orientalis Ikeda genotype is an emerging cattle disease in the US. Since 2017, when T. orientalis Ikeda was discovered in beef cattle in two counties in Virginia, cattle infections have risen to include ~67% of Virginia counties and 14 states. Consistent with New Zealand studies, many infected herds in Virginia were >90% positive upon initial testing without overt evidence of infection. Central bull tests present a unique opportunity to study the effects of T. orientalis Ikeda infections, as bulls from multiple source herds are consolidated. The objective of this study was to determine if infection with T. orientalis Ikeda affected the average daily gain (ADG), adjusted yearling weight (AYW) and breeding soundness of bulls at two test stations in Virginia over a period of years. Materials and methods: The bulls were fed and housed similarly to compare their growth performance and breeding soundness. For T. orientalis Ikeda testing, DNA was extracted from whole blood for quantitative polymerase chain reaction. Results: The number of bulls infected with T. orientalis Ikeda at initial delivery to the stations increased significantly over the years studied. Multivariable linear regression models, using Angus bulls from Virginia test stations, indicated no significant effect on ADG or AYW in bulls that became test positive during the test or were positive for the duration, compared to Angus bulls that were negative for the duration. At LOC A, the odds of passing a breeding soundness exam (BSE) were not significantly different for bulls that turned positive during the test or were positive for the duration, compared to bulls that were negative for the duration of the test. At LOC B, bulls that became positive during the test were 2.4 times more likely (95% CI: 1.165–4.995, p = 0.016) to pass their BSE compared to bulls that remained negative throughout the test. Discussion: We do not suppose that an obscured infection of T. orientalis Ikeda is protective for bulls to pass a BSE. However, this study demonstrates an obscured infection of T. orientalis Ikeda does not negatively affect weight gain or achievement of a satisfactory BSE rating at the central bull test stations in Virginia.
Evaluation of Apparent Metabolizable Energy and Apparent Ileal Amino Acid Digestibility of Spirulina (Arthrospira platensis) in Broiler Chickens and Laying Hens
O’Lear Reid, Taylor K.; Gardner, Katherine E.; Paglia, Kayla L.; Ulans, Alexandra C. M.; Spierling, Ruth E.; Edwards, Mark S.; Lundquist, Tryg J.; McFarlane, Zach D.; Pokharel, Siroj; Bennett, Darin C. (MDPI, 2024-11-20)
Our study objective was to determine the apparent metabolizable energy (AME) and apparent ileal amino acid digestibility (AIAAD) of spirulina fed to broiler chickens and laying hens using the difference method. In both experiments, birds were either fed corn-soybean meal basal diets, containing no spirulina and formulated to provide the nutrient requirements of either broilers or layers, or fed test diets consisting of 25% spirulina and 75% of the appropriate basal diet. Titanium dioxide was added to all diets as an indigestible marker. The diets were fed to 10 replicate cages/treatment of broilers and 15 replicate cages/treatment of laying hens. The AME of spirulina for broilers was significantly lower (p < 0.05) (2368 ± 104 kcal/kg, as fed) than for laying hens (3144 ± 173 kcal/kg, as fed), suggesting bird type and age may influence energy utilization. The AIAAD of spirulina fed to broiler chickens did not differ from that of laying hens (p > 0.05), except for valine, alanine, and glycine, which were all significantly higher in laying hens (p < 0.05). Overall, the AIAAD for nonessential amino acids averaged 81.1%, with no significant difference between essential and nonessential amino acids. Differences in spirulina nutrient content cited in the literature support further research to determine the optimal inclusion of this alternative ingredient in broiler and layer diets.
Mitochondrial Abundance and Function Differ Across Muscle Within Species
Yen, Con-Ning; Bodmer, Jocelyn S.; Wicks, Jordan C.; Zumbaugh, Morgan D.; Persia, Michael E.; Shi, Tim H.; Gerrard, David E. (MDPI, 2024-10-16)
Background: Mitochondria are considered the powerhouse of cells, and skeletal muscle cells are no exception. However, information regarding muscle mitochondria from different species is limited. Methods: Different muscles from cattle, pigs and chickens were analyzed for mitochondrial DNA (mtDNA), protein and oxygen consumption. Results: Bovine oxidative muscle mitochondria contain greater mtDNA (p < 0.05), protein (succinate dehydrogenase, SDHA, p < 0.01; citrate synthase, CS, p < 0.01; complex I, CI, p < 0.05), and oxygen consumption (p < 0.01) than their glycolytic counterpart. Likewise, porcine oxidative muscle contains greater mtDNA (p < 0.01), mitochondrial proteins (SDHA, p < 0.05; CS, p < 0.001; CI, p < 0.01) and oxidative phosphorylation capacity (OXPHOS, p < 0.05) in comparison to glycolytic muscle. However, avian oxidative skeletal muscle showed no differences in absolute mtDNA, SDHA, CI, complex II, lactate dehydrogenase, or glyceraldehyde 3 phosphate dehydrogenase compared to their glycolytic counterpart. Even so, avian mitochondria isolated from oxidative muscles had greater OXPHOS capacity (p < 0.05) than glycolytic muscle. Conclusions: These data show avian mitochondria function is independent of absolute mtDNA content and protein abundance, and argue that multiple levels of inquiry are warranted to determine the wholistic role of mitochondria in skeletal muscle.
Functionalized Graphene-Based Biosensors for Early Detection of Subclinical Ketosis in Dairy Cows
Chick, Shannon; Kachouei, Matin Ataei; Knowlton, Katharine; Ali, Md. Azahar (American Chemical Society, 2024-08-22)
Precision livestock farming utilizing advanced diagnostic tools, including biosensors, can play a key role in the management of livestock operations to improve the productivity, health, and well-being of animals. Detection of ketosis, a metabolic disease that occurs in early lactation dairy cows due to a negative energy balance, is one potential on-farm use of biosensors. Betahydroxybutyrate (βHB) is an excellent biomarker for monitoring ketosis in dairy cows because βHB is one of the main ketones produced during this metabolic state. In this report, we developed a low-cost, Keto-sensor (graphene-based sensor) for the detection of βHB concentrations in less than a minute. On this device, graphene nanosheets were layered onto a screen-printed electrode (SPE), and then, a stabilized enzyme (beta-hydroxybutyrate dehydrogenase, NAD⁺, and glycerol) was used to functionalize the graphene surface enabled by EDC−NHS conjugation chemistry. The Keto-sensor offers an analytical sensitivity of 10 nM and a limit of detection (LoD) of 0.24 nM within a detection range of 0.01 μM−3.00 mM. Spike testing indicates that the Keto-sensor can detect βHB in serum samples from bovines with subclinical ketosis. The Keto-sensor developed in this study shows promising results for early detection of subclinical ketosis on farms.
Advancing Multi-Ion Sensing with Poly-Octylthiophene: 3D-Printed Milker-Implantable Microfluidic Device
Ali, Md. Azahar; Kachoueim, Matin Ataei (Wiley-VCH, 2024)
On-site rapid multi-ion sensing accelerates early identification of environmental pollution, water quality, and disease biomarkers in both livestock and humans. This study introduces a pocket-sized 3D-printed sensor, manufactured using additive manufacturing, specifically designed for detecting iron (Fe²⁺), nitrate (NO₃⁻), calcium (Ca²⁺), and phosphate (HPO₄²⁻). A unique feature of this device is its utilization of a universal ion-to-electron transducing layer made from highly redox-active poly-octylthiophene (POT), enabling an all-solid-state electrode tailored to each ion of interest. Manufactured with an extrusion-based 3D printer, the device features a periodic pattern of lateral layers (width = 80 μm), including surface wrinkles. The superhydrophobic nature of the POT prevents the accumulation of nonspecific ions at the interface between the gold and POT layers, ensuring exceptional sensor selectivity. Lithography-free, 3D-printed sensors achieve sensitivity down to 1 ppm of target ions in under a minute due to their 3D-wrinkled surface geometry. Integrated seamlessly with a microfluidic system for sample temperature stabilization, the printed sensor resides within a robust, pocket-sized 3D-printed device. This innovation integrates with milking parlors for real-time calcium detection, addressing diagnostic challenges in on-site livestock health monitoring, and has the capability to monitor water quality, soil nutrients, and human diseases.
Validation of a Commercial ELISA Kit for Non-Invasive Measurement of Biologically Relevant Changes in Equine Cortisol Concentrations
Share, Elizabeth R.; Mastellar, Sara L.; Suagee-Bedore, Jessica K.; Eastridge, Maurice L. (MDPI, 2024-10-01)
The measurement of fecal cortisol/corticosterone metabolites (FCMs) is often used to quantify the stress response. The sampling method is relatively non-invasive, reduces concern for elevation of cortisol from the sampling method, and has been shown to measure cortisol more consistently without the daily diurnal rhythm observed in blood. Commercial ELISA (enzyme-linked immunoassay) kits offer benefits over previously validated immunoassay methods but lack validation. The objective of this study was to evaluate a commercial ELISA kit (Arbor Assays^TM DetectX^® Cortisol ELISA kit, K003-H1, Ann Arbor, MI, USA) and provide analytical and biologic validation of equine fecal and plasma samples. Horses (4 male, 4 female, mean ± SD: 4 ± 5 yr) were transported for 15 min with limited physical and visual contact via a livestock trailer. Blood and fecal samples were collected pre- and post-transportation. Parallelism, accuracy, and precision tests were used to analytically validate this kit. Data were analyzed using PROC MIXED in SAS 9.4. Plasma cortisol concentrations increased in response to trailering (254.5 ± 26.4 nmol/L, 0 min post-transportation) compared to pre-transportation (142.8 ± 26.4 nmol/L). FCM concentrations increased 24 h post-trailering (10.8 ± 1.7 ng/g) when compared to pre-transportation (7.4 ± 1.7 ng/g). These data support that changes in FCMs can be observed 24 h post-stressor. In conclusion, the Arbor Assays^TM DetectX^® Cortisol ELISA kit is a reliable, economic option for the measurement of biologically relevant changes in cortisol in equine plasma and FCMs.
Growth and wear characteristics of individual claws in young dairy calves
Souza, Ana F.; Wallace, R. L.; Tomlinson, D. J.; Earleywine, T.; Socha, M. T.; Drackley, J. K.; Osorio, Johan S. (Elsevier, 2024-01-15)
Data are limited on how cow hooves develop early in life and how this will affect susceptibility to lameness and claw disorders later in life. The aim of this study was to characterize individual claw growth and wear in dairy calves. A total of 90 male Holstein calves <1 wk old were enrolled in this completely randomized design experiment and monitored until wk 20 of age. Evaluation of hoof development was conducted by visual inspection, and individual claw measurements were taken with a graduated ruler. Claws were numbered from 1 to 8 to maintain consistent data collection, where front claws were numbered 1 to 4 (left to right) and rear claws were 5 to 8. Lateral claws were numbered 1, 4, 5, and 8, and medial claws were 2, 3, 6, and 7. Measurements included length from the coronary band to the end of the hoof wall and from the coronary band to the groove line, resulting in the variables claw length (CL) and groove length (GL), respectively. Hoof development was evaluated at wk 0, 5, 10, 15, and 20. All evaluations were performed by the same person throughout the study to eliminate variation between observers. Hoof growth and wear were derived from CL and GL measurements and analyzed from wk 0 to 20. Claw length at wk 0 was different across claw positions, and maximal claw length was observed in claws in positions 6 and 7 (i.e., rear medial claws). A similar growth pattern in claw length was observed when evaluated from wk 0 to 20, where a greater claw length was observed in claws 6 and 7 compared with other claws. In contrast to claw length, claw wear at wk 20 was lower in claws 6 and 7 compared with other claws. Compared with rear claws, front claws had greater wear at wk 20, and compared with medial claws, lateral claws had greater wear at wk 20. Factors associated with claw length differences at wk 0 remain to be elucidated, but the fact that this uneven claw length difference was maintained 20 wk after birth is puzzling. The complementary claw length to wear described greater wear in claws 1 and 4 (i.e., front lateral) in young calves, which is translated into lower claw length in the same claws by wk 20 after birth. Future research in postnatal hoof growth should strive to understand the potential biological significance of this effect on lameness resistance and longevity of dairy cows.
Altered microRNA composition in the uterine lumen fluid in cattle (Bos taurus) pregnancies initiated by artificial insemination or transfer of an in vitro produced embryo
Biase, Fernando H.; Moorey, Sarah E.; Schnuelle, Julie G.; Rodning, Soren; Ortega, Martha S.; Spencer, Thomas E. (2024-09-13)
Background: MicroRNAs (miRNAs) are presented in the uterine lumen of many mammals, and in vitro experiments have determined that several miRNAs are important for the regulation of endometrial and trophoblast functions. Our aim was to identify and contrast the miRNAs present in extracellular vesicles (EVs) in the uterine lumen fluid (ULF) at the onset of attachment in cattle pregnancies (gestation d 18) initiated by artificial insemination (AI) or by the transfer of an in vitro-produced blastocyst (IVP-ET). A third group had no conceptus after the transfer of an IVP embryo. Results: The abundance of 263 annotated miRNAs was quantified in the EVs collected from ULF. There was an increase in the transcript abundance of 20 miRNAs in the ULF EVs from the AI pregnant group, while 4 miRNAs had a lower abundance relative to the group not containing a conceptus. Additionally, 4 miRNAs were more abundant in ULF EVs in the AI pregnant group relative to IVP-ET group (bta-mir-17, bta-mir-7-3, MIR7-1, MIR18A). Specific miRNAs in the ULF EVs were co-expressed with messenger RNAs expressed in extra-embryonic tissues and endometrium, including genes that are known to be their targets. Conclusions: The results provide biological insights into the participation of miRNAs in the regulation of trophoblast proliferation and differentiation, as well as in endometrium receptivity. The knowledge that in vitro cultured embryos can contribute to the altered abundance of specific miRNAs in the uterine lumen can lead to the development of corrective approaches to reduce conceptus losses during the first month of pregnancy in cattle.
Impact of Monensin Sodium and Essential Limonene Oil on the Fermentation and Chemical Composition of Total Mixed Ration Silages with Moisture Variations
de Andrade, Ronnie Coêlho; Orrico Junior, Marco Antonio Previdelli; da Silva, Yara América; Retore, Marciana; Fernandes, Tatiane; Orrico, Ana Carolina Amorim; Vargas Junior, Fernando Miranda de; Amaral, Isabele Paola de Oliveira (MDPI, 2024-08-09)
Monensin and essential oils have antimicrobial properties that may impact silage fermentation. The present study was divided into two trials to evaluate the effects of monensin (MON) and essential limonene oils (ELO) as additives in the ensiling of total mixed ration (TMR). In the first assay, TMR was tested with sheep in growth (65% dry matter—DM) using the following treatments: control (no additive), MON35 (35 mg of monensina per kg of DM), MON45 (45 mg of monensina per kg of DM), ELO300 (300 mg of essential limonene oil per kg of DM), and ELO600 (600 mg of essential limonene oil per kg of DM). In the second assay, the same treatments were used in TMR for lactating cows under two moisture conditions (30% and 40% DM). The parameters assessed included fermentative losses, short-chain fatty acid profiles, aerobic stability (hours needed for silage to reach 2 °C above ambient), chemical composition, and in vitro DM digestibility of the silages. Treatment averages were compared using the Scott–Knott test at 5% significance. In the first assay, the treatments with ELO had the lowest (p < 0.05) pH values and the highest (p < 0.05) lactic acid concentrations, with treatment ELO600 leading to the highest (p < 0.05) aerobic stability (297.88 h). Only the starch contents of the ELO treatments were lower (p < 0.05) than the others. In the second assay, the silages with the highest moisture contents and ELO600 exhibited the lowest (p < 0.05) values of DM recovery, lactic acid, and pH. The highest (p < 0.05) lactic acid:acetic acid ratios were observed in the silages with the most moisture added with MON35 and MON45. The use of MON and ELO increased aerobic stability, with the highest (p < 0.05) values observed for ELO600 and MON35. The treatments with MON and ELO resulted in silages with the lowest (p < 0.05) fiber contents and highest ether extract and starch contents when compared with control. Thus, MON and essential oils improve fermentative quality but ELO should be used in lower doses in humid silages to avoid negative fermentation impacts.
Identification of novel cattle (Bos taurus) genes and biological insights of their function in pre-implantation embryo development
Schettini, Gustavo P.; Morozyuk, Michael; Biase, Fernando H. (2024-08-09)
Background: Appropriate regulation of genes expressed in oocytes and embryos is essential for acquisition of developmental competence in mammals. Here, we hypothesized that several genes expressed in oocytes and pre-implantation embryos remain unknown. Our goal was to reconstruct the transcriptome of oocytes (germinal vesicle and metaphase II) and pre-implantation cattle embryos (blastocysts) using short-read and long-read sequences to identify putative new genes. Results: We identified 274,342 transcript sequences and 3,033 of those loci do not match a gene present in official annotations and thus are potential new genes. Notably, 63.67% (1,931/3,033) of potential novel genes exhibited coding potential. Also noteworthy, 97.92% of the putative novel genes overlapped annotation with transposable elements. Comparative analysis of transcript abundance identified that 1,840 novel genes (recently added to the annotation) or potential new genes were differentially expressed between developmental stages (FDR < 0.01). We also determined that 522 novel or potential new genes (448 and 34, respectively) were upregulated at eight-cell embryos compared to oocytes (FDR < 0.01). In eight-cell embryos, 102 novel or putative new genes were co-expressed (|r|> 0.85, P < 1 × 10–8) with several genes annotated with gene ontology biological processes related to pluripotency maintenance and embryo development. CRISPR-Cas9 genome editing confirmed that the disruption of one of the novel genes highly expressed in eight-cell embryos reduced blastocyst development (ENSBTAG00000068261, P = 1.55 × 10–7). Conclusions: Our results revealed several putative new genes that need careful annotation. Many of the putative new genes have dynamic regulation during pre-implantation development and are important components of gene regulatory networks involved in pluripotency and blastocyst formation.
Genetic diversity of United States Rambouillet, Katahdin and Dorper sheep
Becker, Gabrielle M.; Thorne, Jacob W.; Burke, Joan M.; Lewis, Ronald M.; Notter, David R.; Morgan, James L. M.; Schauer, Christopher S.; Stewart, Whit C.; Redden, R. R.; Murdoch, Brenda M. (2024-07-30)
Background: Managing genetic diversity is critically important for maintaining species fitness. Excessive homozygosity caused by the loss of genetic diversity can have detrimental effects on the reproduction and production performance of a breed. Analysis of genetic diversity can facilitate the identification of signatures of selection which may contribute to the specific characteristics regarding the health, production and physical appearance of a breed or population. In this study, breeds with well-characterized traits such as fine wool production (Rambouillet, N = 745), parasite resistance (Katahdin, N = 581) and environmental hardiness (Dorper, N = 265) were evaluated for inbreeding, effective population size (Ne), runs of homozygosity (ROH) and Wright’s fixation index (FST) outlier approach to identify differential signatures of selection at 36,113 autosomal single nucleotide polymorphisms (SNPs). Results: Katahdin sheep had the largest current Ne at the most recent generation estimated with both the GONe and NeEstimator software. The most highly conserved ROH Island was identified in Rambouillet with a signature of selection on chromosome 6 containing 202 SNPs called in an ROH in 50 to 94% of the individuals. This region contained the DCAF16, LCORL and NCAPG genes that have been previously reported to be under selection and have biological roles related to milk production and growth traits. The outlier regions identified through the FST comparisons of Katahdin with Rambouillet and Dorper contained genes with known roles in milk production and mastitis resistance or susceptibility, and the FST comparisons of Rambouillet with Katahdin and Dorper identified genes related to wool growth, suggesting these traits have been under natural or artificial selection pressure in these populations. Genes involved in the cytokine-cytokine receptor interaction pathways were identified in all FST breed comparisons, which indicates the presence of allelic diversity between these breeds in genomic regions controlling cytokine signaling mechanisms. Conclusions: In this paper, we describe signatures of selection within diverse and economically important U.S. sheep breeds. The genes contained within these signatures are proposed for further study to understand their relevance to biological traits and improve understanding of breed diversity.
Retrospective Single Nucleotide Polymorphism Analysis of Host Resistance and Susceptibility to Ovine Johne’s Disease Using Restored FFPE DNA
Kravitz, Amanda; Liao, Mingsi; Morota, Gota; Tyler, Ron; Cockrum, Rebecca; Manohar, B. Murali; Ronald, B. Samuel Masilamoni; Collins, Michael T.; Sriranganathan, Nammalwar (MDPI, 2024-07-15)
Johne’s disease (JD), also known as paratuberculosis, is a chronic, untreatable gastroenteritis of ruminants caused by Mycobacterium avium subsp. paratuberculosis (MAP) infection. Evidence for host genetic resistance to disease progression exists, although it is limited due to the extended incubation period (years) and diagnostic challenges. To overcome this, previously restored formalin-fixed paraffin embedded tissue (FFPE) DNA from archived FFPE tissue cassettes was utilized for a novel retrospective case-control genome-wide association study (GWAS) on ovine JD. Samples from known MAP-infected flocks with ante- and postmortem diagnostic data were used. Cases (N = 9) had evidence of tissue infection, compared to controls (N = 25) without evidence of tissue infection despite positive antemortem diagnostics. A genome-wide efficient mixed model analysis (GEMMA) to conduct a GWAS using restored FFPE DNA SNP results from the Illumina Ovine SNP50 Bead Chip, identified 10 SNPs reaching genome-wide significance of p < 1 × 10⁻⁶ on chromosomes 1, 3, 4, 24, and 26. Pathway analysis using PANTHER and the Kyoto Encyclopedia of Genes and Genomes (KEGG) was completed on 45 genes found within 1 Mb of significant SNPs. Our work provides a framework for the novel use of archived FFPE tissues for animal genetic studies in complex diseases and further evidence for a genetic association in JD.
Non-Alcoholic Fatty Liver Disease Induced by Feeding Medium-Chain Fatty Acids Upregulates Cholesterol and Lipid Homeostatic Genes in Skeletal Muscle of Neonatal Pigs
Gerrard, Samuel D.; Biase, Fernando H.; Yonke, Joseph A.; Yadav, Ravi; Shafron, Anthony J.; Sunny, Nishanth E.; Gerrard, David E.; El-Kadi, Samer W. (MDPI, 2024-07-11)
Non-alcoholic fatty liver disease (NAFLD) is a range of disorders characterized by lipid accumulation in hepatocytes. Although this spectrum of disorders is associated with adult obesity, recent evidence suggests that this condition could also occur independently of obesity, even in children. Previously, we reported that pigs fed a formula containing medium-chain fatty acids (MCFAs) developed hepatic steatosis and weighed less than those fed an isocaloric formula containing long-chain fatty acids (LCFAs). Our objective was to determine the association between NAFLD and the skeletal muscle transcriptome in response to energy and lipid intake. Neonatal pigs were fed one of three formulas: a control formula (CONT, n = 6) or one of two isocaloric high-energy formulas containing either long (LCFA, n = 6) or medium (MCFA, n = 6) chain fatty acids. Pigs were fed for 22 d, and tissues were collected. Body weight at 20 and 22 d was greater for LCFA-fed pigs than their CONT or MCFA counterparts (p < 0.005). Longissimus dorsi weight was greater for LCFA compared with MCFA, while CONT was intermediate (p < 0.05). Lean gain and protein deposition were greater for LCFA than for CONT and MCFA groups (p < 0.01). Transcriptomic analysis revealed 36 differentially expressed genes (DEGs) between MCFA and LCFA, 53 DEGs between MCFA and CONT, and 52 DEGs between LCFA and CONT (FDR < 0.2). Feeding formula high in MCFAs resulted in lower body and muscle weights. Transcriptomics data suggest that the reduction in growth was associated with a disruption in cholesterol metabolism in skeletal muscles.
Refining flowering date enhances sesame yield independently of day-length
Sabag, Idan; Pnini, Shaked; Morota, Gota; Peleg, Zvi (2024-07-26)
Background: The transition from vegetative to reproductive growth is a key factor in yield maximization. Sesame (Sesamum indicum), an indeterminate short-day oilseed crop, is rapidly being introduced into new cultivation areas. Thus, decoding its flowering mechanism is necessary to facilitate adaptation to environmental conditions. In the current study, we uncover the effect of day-length on flowering and yield components using F₂ populations segregating for previously identified quantitative trait loci (Si_DTF QTL) confirming these traits. Results: Generally, day-length affected all phenotypic traits, with short-day preceding days to flowering and reducing yield components. Interestingly, the average days to flowering required for yield maximization was 50 to 55 days, regardless of day-length. In addition, we found that Si_DTF QTL is more associated with seed-yield and yield components than with days to flowering. A bulk-segregation analysis was applied to identify additional QTL differing in allele frequencies between early and late flowering under both day-length conditions. Candidate genes mining within the identified major QTL intervals revealed two flowering-related genes with different expression levels between the parental lines, indicating their contribution to sesame flowering regulation. Conclusions: Our findings demonstrate the essential role of flowering date on yield components and will serve as a basis for future sesame breeding.
Heat Stress Effects on Physiological and Milk Yield Traits of Lactating Holstein Friesian Crossbreds Reared in Tanga Region, Tanzania
Habimana, Vincent; Nguluma, Athumani Shabani; Nziku, Zabron Cuthibert; Ekine - Dzivenu, Chinyere Charlotte; Morota, Gota; Mrode, Raphael; Chenyambuga, Sebastian Wilson (MDPI, 2024-06-28)
Global warming caused by climate change is a challenge for dairy farming, especially in sub-Saharan countries. Under high temperatures and relative humidity, lactating dairy cows suffer from heat stress. The objective of this study was to investigate the effects and relationship of heat stress (HS) measured by the temperature–humidity index (THI) regarding the physiological parameters and milk yield and composition of lactating Holstein Friesian crossbred dairy cows reared in the humid coastal region of Tanzania. A total of 29 lactating Holstein Friesian x Zebu crossbred dairy cows with 50% (HF50) and 75% (HF75) Holstein Friesian gene levels in the second and third months of lactation were used. The breed composition of Holstein Friesians was determined based on the animal recording system used at the Tanzania Livestock Research Institute (TALIRI), Tanga. The data collected included the daily temperature, relative humidity, daily milk yield, and physiological parameters (core body temperature, rectal temperature, respiratory rate, and panting score). THI was calculated using the equation of the National Research Council. The THI values were categorized into three classes, i.e., low THI (76–78), moderate THI (79–81), and high THI (82–84). The effects of THI on the physiological parameters and milk yield and composition were assessed. The effects of the genotype, the parity, the lactation month, and the interaction of these parameters with THI on the milk yield, milk composition, and physiological parameters were also investigated. The results show that THI and its interaction with genotypes, parity, and the lactation month had a highly significant effect on all parameters. THI influenced (p ˂ 0.05) the average daily milk yield and milk fat %, protein %, lactose %, and solids–not–fat %. As the THI increased from moderate to high levels, the average daily milk yield declined from 3.49 ± 0.04 to 3.43 ± 0.05 L/day, while the fat % increased from 2.66 ± 0.05% to 3.04 ± 0.06% and the protein decreased from 3.15 ± 0.02% to 3.13 ± 0.03%. No decline in lactose % was observed, while the solid–not–fat % declined from 8.56 ± 0.08% to 8.55 ± 0.10% as the THI values increased from moderate to high. Also, the THI influenced physiological parameters (p ˂ 0.05). The core body temperature (CBT), rectal temperature (RT), respiratory rate (RR) and panting score (PS) increased from 35.60 ± 0.01 to 36.00 ± 0.01 °C, 38.03 ± 0.02 to 38.30 ± 0.02 °C, 62.53 ± 0.29 to 72.35 ± 0.28 breaths/min, and 1.35 ± 0.01 to 1.47 ± 0.09, respectively, as the THI increased from low to high. The THI showed a weak positive correlation with the average daily milk yield and fat percentage, whereas the protein, lactose, and solids–not–fat percentages showed negative relationships with THI (p ≤ 0.05). CBT, RT, RR, and PS showed positive relationships (p ≤ 0.05) with THI. These negative relationships indicate that there is an antagonistic correlation between sensitivity to HS and the level of production. It is concluded that the THI, the genotype, the parity, and the lactation month, along with their interactions with THI, significantly influenced the milk yield, milk composition, and physiological parameters of lactating Holstein Friesian dairy crosses at THI thresholds ranging from 77 to 84.
Determining muscle plasticity and meat quality development of low-input extended fed market-ready steers
Wicks, Jordan C.; Wivell, Alexis L.; Beline, Mariane; Zumbaugh, Morgan D.; Bodmer, Jocelyn S.; Yen, Con-Ning; Johnson-Schuster, Chantal; Wilson, Thomas B.; Greiner, Scott P.; Johnson, Sally E.; Shi, Tim H.; Silva, Saulo Luz; Gerrard, David E. (Oxford University Press, 2024-05-02)
In March 2020, the World Health Organization declared COVID-19 a pandemic, which ultimately led to many meat processors temporarily shutting down or reducing processing capacity. This backlog in processing capacity forced many feedlots to retain cattle for longer periods of time and assume the risk of major market fluctuations. The aim of this study was to understand how a dietary insult affects meat quality and muscle metabolism in market-ready steers (590 kg). Sixteen market-ready (590 kg) commercial Angus crossbred steers were subjected to a maintenance diet of either forage or grain for 60 d. Longissimus lumborum (LL) muscle samples were collected immediately postmortem and processed for characteristics reflecting the underlying muscle fiber type and energy state of the tissue. Despite cattle being subjected to a 60-d feeding period, there were no detectable differences (P > 0.05) in carcass characteristics, color of lean, or ultimate pH (pHu). Moreover, our data show that muscle plasticity is rather resilient, as reflected by lack of significance (P > 0.05) in oxidative and glycolytic enzymes, myosin heavy chain isoforms (MyHC), myoglobin, and mitochondrial DNA (mtDNA) contents. These data show that market-ready steers are capable of withstanding a low-input feeding strategy up to 60 d without dramatically impacting underlying muscle characteristics and meat quality development.
Effects of single- or pair-housing on the welfare of shelter dogs: Behavioral and physiological indicators
Hecker, Grace; Martineau, Katherine; Scheskie, Mariah; Hammerslough, Rhonda; Feuerbacher, Erica N. (PLOS, 2024-06-12)
Dogs are often housed alone in shelter settings to reduce injury and disease spread. However, social isolation can be a stressor for dogs. Prior studies have suggested that cohousing can produce behavioral and physiological benefits. These studies have typically focused on laboratory dogs or shelter dogs that have been kenneled for several months. Thus, those results might not necessarily generalize to shelter dogs, many of which have shorter lengths of stay than those dogs studied to date, and might be cohoused soon after intake. In fact, being pair-housed could, in the short term, be more stressful as dogs have to navigate novel social situations in small spaces. We investigated the behavioral and physiological effects of single- or pair-housing shelter dogs, most of which had recently entered the shelter. We collected behavioral data on 61 dogs (30 single-housed; 31 pair-housed) daily across seven days; we also collected urine for cortisol:creatinine analysis on a subset (22 single-housed; 18 pair-housed) for eight days (each day of the seven-day study plus a baseline sample on Day 0, prior to dogs’ enrollment). We found pair-housed dogs engaged in three stressrelated behaviors (lip licking, whining, and ears back) significantly less frequently than single- housed dogs. When we analyzed the change in urinary cortisol:creatinine (Days 1–7 values minus Day 0 value), we found that pair-housed dogs generally showed a greater decrease in cortisol:creatinine levels than single-housed dogs. Pair-housed dogs also had significantly shorter lengths of stay, but we did not detect any effect on dog-dog skills. Overall, we found well-matched pair-housing can have both proximate and ultimate welfare benefits for shelter dogs.
A Multi-Institutional Description of Processes and Outcomes of Postbaccalaureate Research Education Programs in the Mid-Atlantic Region
Wright, Cynthia F.; Kasman, Laura M.; Robinson, Donita L.; Carey, Gregory B.; Hall, Joshua D.; Lloyd, Joyce A.; Shiang, Rita; Smith, Edward J.; Wilson, Katherine L. (Lippincott Williams & Wilkins, 2023-12-28)
Outcome data from 6 National Institutes of Health-funded Postbaccalaureate Research Education Programs (PREPs) in the Mid-Atlantic region were combined to give a multi-institutional perspective on their scholars' characteristics and progress through biomedical research training. The institutions hosting these programs were Johns Hopkins University School of Medicine, the Medical University of South Carolina, the University of Maryland School of Medicine, the University of North Carolina at Chapel Hill, Virginia Commonwealth University, and Virginia Polytechnic Institute and State University. The authors summarize the institutional pathways, demographics, undergraduate institutions, and graduate institutions for a total of 384 PREP scholars who completed the programs by June 2021. A total of 228 (59.4%) of these PREP scholars identified as Black or African American, 116 (30.2%) as Hispanic or Latinx, and 269 (70.0%) as female. The authors found that 376 of 384 scholars (97.9%) who started PREP finished their program, 319 of 376 (84.8%) who finished PREP matriculated into PhD or MD/PhD programs, and 284 of 319 (89.0%) who matriculated have obtained their PhD or are successfully making progress toward their PhD.
Evaluating Different Methods to Establish Biodiverse Swards of Native Grasses and Wildflowers for Pasturelands
Kubesch, Jonathan O. C.; Greiner, Scott P.; Pent, Gabriel J.; Reid, J. Leighton; Tracy, Benjamin F. (MDPI, 2024-05-14)
Many cool-season pastures in the southeastern U.S. are dominated by a competitive cool-season grass, tall fescue (Schedonorus arundinaceus), and lack substantial plant diversity. Planting native warm-season grasses (NWSGs) and wildflowers (WFs) into these pastures could provide summer forage for cattle and more floral resources for pollinators. This paper summarizes field experiments designed to evaluate different spatiotemporal planting arrangements of NWSGs and WFs to improve their establishment success. The study was conducted from April 2021 to October 2023 in central Virginia (USA). Planting treatments included NWSG and WF mixtures planted: (1) together in the same space, (2) spatially separated in space (i.e., side by side), or (3) temporally separated where NWSGs and WFs were planted in difference sequences. Results showed few differences in forage mass, floral production, and botanical composition as well as stand density in 2021 and 2022. In 2023, NWSG abundance was greater where grasses were planted first or mixed with WFs. Similarly, the WF component was favored when they were planted before NWSGs. Overall, planting NWSG and WF mixes separately, either spatially or temporally, favors successful establishment and could offer more flexibility for using selective herbicides to suppress the heavy weed pressure that often accompanies these plantings.

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