Scholarly Works, School of Animal Sciences
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- Companion animal foster caregiving: a scoping review exploring animal and caregiver welfare, barriers to caregiver recruitment and retention, and best practices for foster care programs in animal sheltersPhillips, Grace E.; Gunter, Lisa M. (PeerJ, 2024-12-13)Each year, millions of animals enter animal shelters across the United States and are met with a variety of potential stressors that can negatively impact their experience, including noise, confinement, and social isolation. Foster care, a unique form of human–animal interaction, is increasingly understood to be an effective tool for improving welfare by allowing animals to escape the stressors of the shelter, providing an environment that allows for greater social interaction, and offering opportunities for improved health and behavior. This review includes 42 published articles, reports, master’s theses, and doctoral dissertations that have previously evaluated companion animal foster care programs. While scientific literature in this area has increased over the last decade, no review of the research exploring companion animal fostering has been published. Here, we examine foster care programs and their effects on human and animal welfare, evaluate the successes and challenges of supporting shelter foster care programs, recommend best practices for programmatic success, illuminate discrepancies in equity and diversity of caregiver engagement, and offer directions for future research in animal foster caregiving. The examinations in this review conclude that fostering provides both proximate (i.e., physiological and behavioral) and distal (i.e., length of stay and adoption outcomes) welfare benefits for shelter animals as well as their caregivers. Companion animal foster care programs may be further improved by providing greater caregiver support and increasing the diversity and extent of community engagement. Meanwhile, scientific investigations should explore lesser-researched components of foster care programs that are not yet well understood.
- Environmental complexity impacts anxiety in broiler chickens depending on genetic strain and body weightUlans, Alexandra; Brooks, George C.; Jacobs, Leonie (Nature Portfolio, 2024-07-30)The objective was to assess the impact of environmental complexity on affective state (anxiety) in fast- and slow-growing broilers (Gallus gallus domesticus) as they gain weight. Six hundred fast-growing broilers (Ross 708; “fast-growers”) and 600 slow-growing broilers (Hubbard Redbro Mini; “slow-growers”) were raised in 24 pens with simple (standard; SE) or complex (permanent and temporary enrichments; CE) environments. Six birds/pen underwent the attention bias test on day 23 (fast-growers only), 28–29, 35–36, 42–43, and 56–57 (slow-growers only), with individuals only tested once (n = 576). Proportion of birds feeding, time spent vigilant and latencies to eat and step were recorded. Greater vigilance and longer latencies indicate more anxiety. Slow-growers fed more (p = 0.001), were less vigilant (p = 0.003), and stepped sooner than fast-growers (p = 0.007). For both strains, likelihood of feeding was unrelated to weight in SE, but decreased with increasing weight in CE (p = 0.048). Birds in CE stepped sooner than birds in SE (p = 0.030). Vigilance increased with body weight (p = 0.024). These results indicate that affective state (anxiety) can change as birds gain weight, depending on environmental complexity and genetic strain. Overall, slow-growers showed reduced anxiety compared to fast-growers, across housing treatments or weights.
- Pharmacological validation of an attention bias test for conventional broiler chickensda Silva, Marconi Italo Lourenco; Ulans, Alexandra; Jacobs, Leonie (Public Library of Science, 2024-04-09)Fear and anxiety are considered concerns for animal welfare as they are associated with negative affective states. This study aimed to pharmacologically validate an attention bias test (ABT) for broiler chickens (Gallus gallus domesticus) as a cognitive bias test to determine anxiety. Two-hundred-and-four male Ross 708 broiler chickens were arbitrarily allocated to either the anxiogenic or control treatment at 25 days of age (n = 102/treatment). Birds from the anxiogenic group were administered with 2.5 mg of β-CCM (β-carboline-3-carboxylic acid-N-methylamide [FG 7142]) per kg of body weight through an intraperitoneal injection (0.1 ml/100 g of body weight). Birds from the control group were administered with 9 mg of a saline solution per kg of body weight. During ABT, birds were tested in groups of three (n = 34 groups of three birds/treatment) with commercial feed and mealworms as positive stimuli and a conspecific alarm call as a negative stimulus. Control birds were 45 s faster to begin feeding than anxiogenic birds. Birds from the control group vocalized 40 s later and stepped 57 s later than birds from the anxiogenic group. The occurrence of vigilance behaviors did not differ between treatments. This study was successful in pharmacologically validating an attention bias test for fast-growing broiler chickens, testing three birds simultaneously. Our findings showed that latencies to begin feeding, first vocalization, and first step were valid measures to quantify anxiety.
- Machine Learning-Driven Optimization of Livestock Management: Classification of Cattle Behaviors for Enhanced Monitoring EfficiencyZhao, Zhuqing; Shehada, Halah; Ha, Dong; Dos Reis, Barbara; White, Robin; Shin, Sook (ACM, 2024-08-02)Monitoring cattle health in remote and expansive pastures poses significant challenges that necessitate automated, continuous, and real-time behavior monitoring. This paper investigates the effectiveness and reliability sensor-based cattle behavior classification for such monitoring, emphasizing the impact of intelligent feature selection in enhancing classification performance. To achieve this, we developed Wireless Sensor Nodes (WSN) affixed to individual cattle, enabling the capture of 3-axis acceleration data from five cows across varying seasons, spanning from summer to winter. Initially, we extracted a comprehensive set of 52 features, representing a broad spectrum of cow behaviors alongside statistical attributes. To enhance computational efficiency, we employed the Recursive Feature Elimination (RFE) method to distill 30 critical features by discarding redundant or less significant ones. Subsequently, these optimized features were utilized to train four machine learning (ML) models: Support Vector Machine (SVM), k-Nearest Neighbors (k- NN), Random Forest (RF), and Histogram-based Gradient Boosted Decision Trees (HGBDT). Notably, the HGBDT model demonstrated superior performance, achieving remarkable F1-scores of 99.01% for ’grazing’, 98.74% for ’ruminating’, 89.62% for ’lying’, 84.06% for ’standing’, and 91.87% for ’walking’. These findings underscore the potential of our approach to serve as a robust framework for precision livestock farming, offering valuable insights into enhancing cattle health monitoring in remote environments.
- SegIt: Empowering Sensor Data Labeling with Enhanced Efficiency and SecurityZhang, Zhen; Abraham, Samuel; Lee, Alex; Li, Yichen; Morota, Gota; Ha, Dong; Shin, Sook (ACM, 2024-08-02)SegIt is a novel, user-friendly, and highly efficient sensor data labeling tool designed to tackle critical challenges such as data privacy, synchronization accuracy, and memory efficiency inherent in existing labeling tools. While many current sensor data labeling tools provide free online services, they typically necessitate users to upload unlabeled sensor data, alongside video or audio references, to cloud storage for labeling. Nevertheless, such third-party storage exposes user data to potential security risks. SegIt, an innovative open-source tool, provides a software solution for tagging unlabeled sensor data directly on a local computer, ensuring enhanced accuracy, convenience, and, most importantly, data security.
- Embryonic Thermal Programming and Dietary Baicalein Supplementation Post-Hatch: Effects on Broiler Adipose Tissue DepositionSulaiman, Usman; Vaughan, Reagan; Siegel, Paul; Liu, Dongmin; Gilbert, Elizabeth; Cline, Mark (MDPI, 2024-12-10)Optimization of growth performance and fat metabolism in broilers are critical for meat quality and overall production efficiency. This experiment investigated the effects of dietary baicalein supplementation and embryonic heat conditioning (EHC) on the growth performance and adipose tissue metabolism of 10-day old broilers. Fertile eggs were divided into control and EHC groups, with EHC eggs exposed to intermittent heating (39.5 °C) from day 7 to day 16 of incubation. Hatched chicks were further divided into four groups: CC (control control), CT (control treatment with baicalein), EC (embryonic heat control), and ET (embryonic heat treatment with baicalein), and were fed ad libitum. On day 10 post-hatch, blood and adipose tissue samples were collected for analysis. C/EBPα mRNA was lower in the ET group compared to the EC group and higher in the CT group compared to the CC group. PPARγ and HSL mRNAs were elevated in both the ET and CT groups relative to their controls. Additionally, plasma non-esterified fatty acid (NEFA) levels were significantly higher in the CT group compared to the CC group. These results indicate that baicalein supplementation, particularly when combined with embryonic heat conditioning, can modulate fat metabolism and potentially improve the growth performance of broilers, thereby offering insights into strategies for enhancing poultry production.
- Nutritional Value of Nannochloropsis oceanica for Weaner PigletsChaves, Andreia A. M.; Ribeiro, David M.; Martins, Cátia F.; Fernandes, Tatiane; Maia, Margarida R. G.; Fonseca, António J. M.; Cabrita, Ana R. J.; Alves, Susana P.; Pinho, Mário; Bessa, Rui J. B.; de Almeida, André M.; Freire, João P. B. (MDPI, 2024-12-11)This study evaluates the nutritional value of spray-dried Nannochloropsis oceanica biomass to infer its applicability for weaner piglet feeding. Twenty-four piglets were randomly allocated to four dietary treatments (n = 6) with increasing N. oceanica inclusion (0, 5, 10, and 15%) levels. After a 4-day adaptation period, the digestibility experiment lasted two weeks, with daily excreta collection. Total tract apparent digestibility (TTAD), N balance, intestinal pH, histomorphology, and volatile fatty acid (VFA) concentrations were measured. No significant differences were observed in feed intake, growth, or intestinal morphology (p > 0.05). N intake increased linearly (p = 0.005) with N. oceanica inclusion, while N retention efficiency remained unchanged (p = 0.058). VFA concentrations decreased linearly (p < 0.001). The TTAD of dry matter (DM), organic matter, ether extract, and gross energy decreased (p < 0.05) with higher N. oceanica levels, while the ash TTAD increased (p < 0.001). The estimated TTAD values for N. oceanica biomass were 72.5% for DM, 82.9% for N, and 64.4% for gross energy. The digestible energy, metabolisable energy, and digestible crude protein values estimated for N. oceanica were 12.74 MJ/kg DM, 12.40 MJ/kg DM, and 20.4% DM, respectively. This information enabled the first nutritional characterisation of N. oceanica for weaner piglets, ultimately leveraging its use in piglet diet formulation.
- Characterization of In Situ Ruminal Degradation of Crude Protein and Individual Amino Acids from RyegrassMorales, Álvaro G.; Navarro, Álvaro R.; Pulido, Rubén G.; Hanigan, Mark D. (MDPI, 2024-12-13)In temperate pasture-based dairy systems, ryegrass (Lolium perenne L.) is a key forage due to its high crude protein (CP) content, yet its rapid ruminal degradation could limit the supply of rumen-undegraded protein and essential amino acids (EAAs) to dairy cows. This study aimed to investigate the in situ ruminal degradability of CP and individual amino acids (AAs) in fresh ryegrass at the vegetative stage. Three second-parity, rumen-cannulated Holstein Friesian cows (487 kg body weight, 16.5 kg milk/day) were used for the incubation of ryegrass samples collected in different seasons at the vegetative stage. The degradation kinetics were assessed using the Ørskov and McDonald model, with mathematical corrections for microbial contamination. Results showed that the effective degradability (ED) of AAs was generally higher than that of CP (p < 0.05), exceeding 2%, and that some EAAs, particularly lysine, exhibited an ED up to 5.5% greater than CP (p < 0.05). These differences underscore the need for caution when using CP as a proxy for AA degradation in dietary formulations. Given the high degradability of ryegrass AAs, it would be important to monitor and adjust their supply in diets with high ryegrass inclusion to prevent potential deficiencies that could impair milk production and reduce feed efficiency.
- 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 VirginiaGuynn, 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 stationsGuynn, 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 HensO’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 SpeciesYen, 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 CowsChick, 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 DeviceAli, 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 ConcentrationsShare, 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 AssaysTM 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 AssaysTM 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 calvesSouza, 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 embryoBiase, 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 Variationsde 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 developmentSchettini, 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 sheepBecker, 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.