bluuebunny/crossref_metadata_2025 huggingface dataset:
PSVIII-12 Nutrient digestibility, production performance, and eggshell calcium and phosphorus levels of White Leghorn hens fed ahiflower press cake and micronized seed
Authors: Ogory Roseline , Adewole Deborah
Published: September 2024

Laying hens can benefit from dietary inclusions of oil seeds and their co-products such as ahiflower seeds and ahiflower press cake as sources of energy and nutrients. However, the type and inclusion level of the ahiflower product to achieve these beneficial effects is yet to be investigated. This study aims to determine the effect of ahiflower seed and press cake on production performance, nutrient digestibility, and eggshell calcium (Ca) and phosphorus (P) contents in laying hens. A total of 240 64-week-old Lohman LSL-Lite laying hens were randomly allotted to 1 of 8 treatments for 3 periods (4 weeks/period). The experiment was a completely randomized design with six replicate cages/treatment and 5 hens/cage. The treatments included a control diet (CD), or CD supplemented with 10% Flaxseed as a reference oilseed diet (FS), 1%, 5%, and 10% micronized ahiflower seed (AS), and 5%, 10%, and 15% ahiflower press cake (APC). Production performance was determined at the end of each period, while Ca and P concentrations in eggshell and nutrient digestibility were determined in the third period. Dietary treatment had no significant effect (P >0.05) on eggshell P and Ca levels, body weight (BW), feed conversion ratio (FCR), and hen-day production percentage (HDEP). Although feed intake (FI) was significantly reduced (P < 0.05) in 15% APC when compared to CD, it was not different from 5 and 10% APC inclusion levels. Furthermore, FI and HDEP increased (P < 0.05), while FCR and BW decreased (P <0.05) along the periods. Compared to CD (2129kcal/kg), nitrogen corrected apparent metabolizable energy (AMEn) increased (P < 0.05) in 10% FS (2754kcal/kg), 1% (2681kcal/kg), and 10% AS (2546kcal/kg) and 15% APC (2673kcal/kg). 10% APC (78.9) reduced (P <0.05) P digestibility compared to 10%FS (85.5) and 1%AS (78.9). Calcium digestibility was higher (P <0.05) in hens fed 10% FS (85.5) compared to 10%AS (63.0) and 5%,10% and 15%APC but similar to CD (83.4) and 1% (78.9) and 5%AS (65.3). In conclusion, dietary inclusion of up to 10% AS and 15% APC did not affect BW, FCR, and HDEP in older Lohman LSL-Lite laying hens. Also, AMEn and the digestibility of CP, Ca, and P were positively influenced by different inclusion levels of APC and AS.
PSVIII-20 Identification of functional INDELS responsible for alternative splicing in acute stress responders grazing sheep exposed to gastrointestinal nematode infection
Authors: Cunha Samla M F , Schenkel Flávio S , Mallard Bonnie , Karrow Niel A , Cánovas Ángela
Published: September 2024

Gastrointestinal nematodes (GINs) are a major constraint to the sheep industry. Infected animals can develop clinical signs, like anemia, hypoproteinemia, diarrhea, and in extreme cases death. The misuse of anthelmintics to treat infected animals has led to the development of GIN resistance making necessary the integration of different approaches to reduce the impact of GINs on the sheep industry. The application of transcriptomics using RNA-Sequencing technology to better understand the underlying genetic mechanisms of resistance to GIN can help accelerate the genetic gain. This study aimed to identify insertion and deletions (INDELs) responsible for alternative splicing in Rideau x Dorset crossbred sheep with different immune profiles under natural exposure to gastrointestinal nematodes using RNA-Sequencing. High (H) and medium (M) acute stress responders with the highest and lowest worm burden, after natural exposure to GIN, were selected for liver RNA extraction (H; n = 5 and M; n = 6). In addition, GIN-unexposed lambs (U; n = 4) were used as immunological controls. Quality control analyses were performed on fastq files using the CLC Bio Genomics workbench software including the guanine-cytosine (GC) content, ambiguous base content, Phred score, base coverage, nucleotide contributions, and over-represented sequence parameters. Pair-end sequence reads were aligned to the annotated Oar_rambouillet_v.2.0 ovine reference genome. After that, variant discovery analysis and functional consequence analysis were performed using CLC Bio Genomics workbench software to identify INDELs leading to amino acid changes and splice site events (SSEs). Genes associated with the list of INDELs leading to SSE were recovered from Ensembl BioMart. Unique INDELs with SSEs for H, M, and U groups (162, 244, and 161, respectively) and shared (372) among groups were identified. Among them, 4 INDELS with SSE uniquely identified in the M group were located within the NLRC5, SIGLEC1, CFD, and STAT6 genes related to the immune system. Significant enriched metabolic pathways (FDR< 0.05) were identified using the list of genes with INDELs that led to SSEs unique for each group and shared among groups using Reactome. Metabolic pathways related to the immune system response such as cross-presentation of soluble exogenous antigens (endosomes) and NIK noncanonical NF-kB signaling pathways were identified in the M group. These results can help to better understand the mechanisms responsible for the immune response of sheep to GIN.
PSVIII-21 Meta-analysis of nutritive factors influencing mean retention time of digesta in the gastrointestinal tract of broiler chickens
Authors: Hong Grace , Leishman Emily M , Kiarie Elijah , Ellis Jennifer L
Published: September 2024

Broiler chicken meat is an important source of food protein for human consumption globally. Over the last several decades, dramatic changes have been made to broiler genetics, management, and nutrition to increase production efficiency. Different feeds with varying nutrient composition have been researched to target goals such as improving growth and feed conversion ratio. Part of understanding and further improving these feeding programs involves understanding the effects of the feed on nutrient digestibility and animal performance. As such, models are a key tool in the wholistic evaluation of diet, genetics, and management interactions. Towards developing a mechanistic digestion model for broilers, knowledge of mean retention time (MRT, min) of digesta in the gastrointestinal tract (GIT) across a variety of diets is required. To understand the relationship between MRT in broilers and their diet, a systematic literature search and meta-analysis was conducted where 34 articles were found to meet the inclusion criteria. MRT in these studies was measured in various parts of the GIT where 7 studies reported MRT in just one segment (e.g. jejunum), 12 studies reported MRT in multiple combined segments (e.g. jejunum + ileum) and 21 studies reported MRT of the entire GIT. Birds used in these studies included those in the starter, grower, and finisher phases as well as breeders. Nutritional composition of the diets was represented by data on metabolizable energy (ME, kcal/kg), crude fiber (% DM), crude fat (% DM), crude protein (% DM) and calcium (% DM) that was consistently reported across studies. A mixed model (PROC MIXED, in SAS), treating study as a random effect, and using a subset of the data collected where MRT was reported for the entire GIT, and limited to grower and finisher phases, was used to examine the relationship between the diet composition and MRT. Only ME (F1,28.1 = 4.25; P = 0.0486) was found to be significantly related to MRT, where an increase in one kcal/kg of ME resulted in a decrease of MRT by 0.091 minutes (within the range of 2,749 to 3,507 kcal/kg ME). Other nutritional components of the diet were found to have no significant relation to MRT (all P > 0.05), though next steps will examine how the source of ME (fat vs starch vs fiber) impacts this relationship. Although other factors (such as age and feed intake) are still to be considered, the initial results from this study provide valuable insights into how nutritional composition of poultry feeds relates to MRT. Further investigation will also quantify this relationship within segment of the GIT. This work not only provides valuable information to nutritionists, but also lays the groundwork for empirical model development to predict MRT of poultry feed, essential to poultry nutritional models.
PSVIII-19 Assessing methane and carbon dioxide production in beef cows across diverse foraging conditions
Authors: Behrouzi Amir , Bolen Hailey , de Novais Francisco José , Basarab John A , bork Edward , Fitzsimmons Carolyn J
Published: September 2024

Beef cattle grazing across more than 40M ha of Canada’s grasslands is economically significant yet contributes to methane (CH4) emissions. Accurately measuring CH4 emissions across diverse environments presents substantial challenges. Our study investigated CH4 and carbon dioxide (CO2) production in 3-yr-old pregnant crossbred beef cows (n = 30) across different phases of the beef production cycle, including in drylot and while grazing on native rangeland, in Western Canada’s Aspen Parkland region using the GreenFeed Emissions Monitoring System (GEM). During the January to March drylot phase, enteric CH4 and CO2 production of the cows were monitored for 63 d in consort with feed efficiency testing while consuming a mixed oat-barley silage diet. Following this, cows were categorized into three distinct groups based on the standard deviation (SD) of CH4 yield [gּ kg−1 dry matter intake (DMI)]: Low (< 0.5 SD; n = 11), Medium (± 0.5 SD; n = 10), and High (> 0.5 SD; n = 9). Post-calving, cows and calves transitioned to native pastures for CH4 and carbon dioxide (CO2) assessment across three distinct foraging conditions: high-quality, high-quantity forage in summer (SUM; 50 d); moderate-quality, high-quantity forage in September (SEP; 22 d); and finally, low-quality, low-quantity forage in October (OCT; 22 d). We hypothesize that ranking cows based on their CH4 yield (gּ kg−1 DMI) in drylot settings may have the potential to reflect their CH4 production (g/d) during grazing conditions, even without feed intake data. Data were analyzed using the PROC MIXED procedure of SAS to examine CH4 production among cows categorized by their assigned ranking. Spot CH4 and CO2 measurements totaled 1,242, 1,145, and 1,205 for the SUM, SEP, and OCT, production phases, respectively. Average daily visits to GEM units were 1.4 ± 0.1, 1.84 ± 0.1, and 1.96 ± 0.1 for the corresponding phases. While High CH4-ranked cows had methane production similar to Low CH4-ranked cows (234.8 ± 8.2 vs. 235.0 ± 6.0 g/d, respectively), the Medium group had significantly greater methane production (260.5 ± 6.2 g/d; P = 0.008) than the Low and High CH4 groups. Furthermore, significant interactions were observed between CH4 ranking groups and CH4 production during the grazing phase (P = 0.035). Cows in the Medium CH4 group emitted greater amounts of CH4 compared with the High group in SUM (288.2 ± 9.3 vs. 247.0 ± 14.1 g/d) and to the Low group in SEP and OCT (276.5 ± 6.6 vs. 238.1 ± 6.3, and 216.7 ± 7.2 vs. 191.8 ± 7.5 g/d, respectively). In conclusion, the drylot CH4 ranking may hold promise in predicting outcomes for both Low and Medium CH4-ranked groups during grazing phases. However, High CH4-ranked cows had decreased methane production, likely influenced by grazing-induced changes in feed intake and individual feeding behaviors, prompting further exploration.
PSX-13 Assessment of bull buying behavior using a simulated bull auction
Authors: Culbertson Miranda M , Rowan Troy N , Martinez Charles
Published: September 2024

The bull buying behavior of Iowa cattle producers was assessed using an online simulated bull auction. Participants (n = 45) were asked a series of questions to determine the bull type they wished to bid on and the purchase price for the bull. Questions included the breeding objective of the producer and whether the bull would be bred to heifers. Participants were asked to identify the breed of bull they were interested in purchasing, the traits that were the most important to their breeding objective, and the maximum amount that they would be willing to pay. Once the buyer information was complete, the responses were randomly redistributed to other participants. As a result, a participant would receive the buyer information from another individual involved in the simulated bull auction. At this point, the participant role would change from buyer to bidder. A list of 70 bulls with expected progeny differences (EPD) was provided to each participant, and the simulated bull auction was accessed through an online auction platform via cell phones. Participants bid for bulls on behalf of the instructions of the buyer. After the sale, the bidder was asked if they were able to purchase the bull to fit the criteria requested by the buyer and if it was purchased within the given price range. The purchase information was returned to the original participant (i.e., the buyer). The buyer then stated if they were satisfied with the purchased bull. Questionnaires were collected, and information was compiled. The most common breeding objectives were replacement heifers, feeder calves, fed cattle, and profit. Important traits for purchasing a bull were calving ease direct, yearling weight, terminal traits, and docility. Only 16 participants indicated using indexes for selection. Criteria for removing a bull from consideration included low EPD for calving ease direct and docility, and if the bull was horned. Poor index values were listed by 9 participants as a reason to eliminate a bull. Responses from participants as the bidder, 83.7% indicated that the bull was purchased within the provided price range, while 16.3% were unable to purchase a desired bull within the given price range. When asked why the bidder bid on a specific bull, 28 stated the bull met the EPD profile, 16 stated the bull was in the correct price range, seven bulls met a phenotypic profile, and five bulls were purchased due to the bidder running out of time. Of the bulls purchased, 80% of the buyers were satisfied with the bull purchased by the bidder. The results from this simulated bull auction provide insight into tools and methods used by cattle producers when purchasing bulls and what, if any, genetics tools for selection are being used.
PSX-12 Implementation of virtual fencing technology to build resiliency of agriculture systems impacted by wildfire and subsequent flooding
Authors: Ochoa Luis , Utsumi Santiago A , Marta Sara , Perea Andres Ricardo , Spetter Maximiliano J , Ward Marcy , Spackman Casey , Cram Doug , Gifford Craig A
Published: September 2024

The Southwestern U.S. has experienced frequent drought over the past 30 yr, and wildfire frequency and intensity has been increasing which threatens western rangelands. In the west, livestock grazing systems often involve a combination of private, state, and federal land, and the grazing managers must comply with designated grazing plans. In 2022, the Black Fire in southern NM was the second largest wildfire in state history and burned hundreds of thousands of hectares of rangeland including fencing which impeded the ability to comply with grazing management plans. Local extension agents along with area beef producers and federal grazing managers revealed the largest challenge they faced was lack of fencing and fence damage due to wildfire loss and floods. Labor shortages, replacement costs, and difficult terrain inhibited the ability to replace fences and sufficiently manage cattle. Virtual fencing (VF) technology allows containment of cattle without physical fencing, but the technology has not been evaluated in extensive systems in the SW challenged by large pastures and extremely difficult terrain. NMSU Extension worked with producers and federal grazing managers to evaluate the effectiveness of VF as a response to wildfire. All procedures were approved by NMSU Institutional Animal Use and Care Committee (2211000086). Two large allotments (17,233 and 5,776 ha, respectively) were evaluated for cellular receptivity and LoRa WAN connectivity and 2 peaks per allotment were identified for installation of LoRa WAN receiving stations. Two ranchers enrolled in the program and were trained to VF principles and Vence software platforms. Cows (n = 100/rancher) were trained to Vence VF collars utilizing physical fence in conjunction with sound and electrical pulse. After a 4-d training period, cattle were grazed across 2 to 3 large pastures per site. Containment efficacy was evaluated via GPS position data. In allotment A and B, LoRa WAN packet communication was 46% and 37%, respectively. After 230 d of testing, cattle containment using VF in combination with remaining perimeter fence and terrain barriers was estimated at 79% and 94% for pastures A and B, respectively. Producers reported that GPS location data helped reduce gathering time by 1 to 2 wk and increased gathering efficiency by approximately 10%. Results demonstrated that VF technology can reasonably be used in response to partial fencing loss during post-fire recovery and there is a need for Extension to provide support for new technology utilization on ranching operations. Project was supported by USDA/NIFA #2023-68016-38885.
PSXII-4 Intercropping perennial cereal grain crops in alternate or same row seeding method for improved forage yield and quality
Authors: Ugwu Cosmas , Omokanye Akim , Hernandez Guillermo Ramirez , Thilakrathna Malinda S , Hostetller Chelsey , Arora Naveen , Puurveene Dick , Singh Kabal , Olson Alex , Ahmed Khalil
Published: September 2024

Intercropping perennial cereal crops with legume species can offer multiple ecosystem functions and agronomic benefits. This study evaluated the forage dry matter yield (FDMY) and the nutritive value of two perennial cereal grain crop species [ACE 1-rye and Kenza, intermediate wheatgrass (IWG)] intercropped with three perennial legume species (alfalfa, white clover, and sainfoin) using alternate- and same-row seeding methods at five different sites in Alberta. The experimental sites were established in June 2022 using a factorial experimental model with eight treatment factors, including perennial monocultures or intercrop with a legume species. One year after establishment in 2023, the forage dry matter yield (FDMY) varied significantly (P < 0.05) across experimental sites, ranging from 228 kgּ ha-1ּ yr-1 for the IWG/sainfoin intercrop to 6,833 kgּ ha-1ּ yr-1 for the IWG and alfalfa intercrop treatment. Seeding methods (Same or Alternate row) and site location had a significant effect on the FDMY (P = 0.00126), indicating consistent performance in the two cropping systems across diverse environments and site locations. The study assessed eight treatments (cereal-legume combinations) for forage quality performance, of which seven treatments, including Rye-Clover, Rye-Sainfoin, Wheat-Alfalfa, Wheat-Clover, Wheat-Sainfoin, Wheat mono, and Rye mono, showed significant effects on forage quality factors of crude protein (CP), NDF, NDFD-48, and the Relative Feed Value (RFV). The nutritive value of forage varied across different treatments, with CP content ranging from 6.28% to 18.94% and acid detergent fiber (ADF) content ranging from 10.28% to 40.27%. This variation suggests that the protein and digestibility requirements for livestock consumption are met at different stages. Additionally, the study suggests that intercropping perennial cereal grain crops with legume species using either alternate or the same row seeding methods can lead to consistent forage productivity across different sites. The forages from these intercropping systems exhibit adequate concentrations of CP and total digestible nutrient (TDN), with an average TDN concentration across all sites of approximately 59.3%. This makes them suitable for fulfilling the dietary requirements of beef or dairy cows at various developmental stages. Further research is ongoing to investigate ecosystem functions such as biological nitrogen fixation and water-use efficiency to optimize management practices for sustainable forage production.
PSXIII-7 Effects of whole corn on gain and subsequent feedlot and carcass traits of Brahman steers stocked on Tifton 85 bermudagrass
Authors: Rouquette Monte , Banta Jason , Long Charles R , Turner Kyle , Norman Kelli , Paschal Joe , Randel Ronald D
Published: September 2024

Supplementation (SUP) of stocker calves is used to enhance gain and/or adjust for stocking rates (SR). Our objective was to determine the influence of whole corn on performance of steers stocked on Tifton 85 bermudagrass [Cynodon dactylon (L.) Pers. X Cynodon nlemfuensis Vanderyst] (T85) that has documented forage crude protein ranging from 18.5% in June to 13.5% in September. For a 3-yr period, Brahman (Bos indicus) steers, 15 mo old and 275 kg body weight (BW), were stocked on T85 and received daily whole corn at 0 (PAS), 0.3% BW (SUP3), or 0.6% BW (SUP6). A fourth treatment included SUP6 at an increased stocking rate (SUP6SR). The 3-yr average SR of 275 kg steers was 11 steersּ ha-1 on PAS, SUP3, and SUP6, and 15 steersּ ha-1 on SUP6SR. Average daily gain (ADG) was similar for SUP steers at 0.98 kgּ d-1 (SUP6), 0.92 kgּ d-1 (SUP3), and 0.92 kgּ d-1 (SUP6SR), but greater (P = 0.002) than PAS steers at 0.84 kgּ d-1. Steer gainּ ha-1 was greatest (P = 0.001) for SUP6SR at 1230 kgּ ha-1. Gain ha-1 was similar for SUP6 and SUP3 at 1,010 kgּ ha-1 and 941 kgּ ha-1, respectively, and similar for SUP3 and PAS (860 kg-1). Body weights off pasture tended to be greater (P = 0.083) for all SUP steers at 370 kg than PAS steers at 354 kg. Body condition score off pasture was similar for all SUP steers at 5.7 and different (P = 0.001) from PAS steers at 5.2. At termination of stocking, steers were shipped 700 km to a commercial feedlot in South Texas. Each year, steers were fed in the same pen until a visual assessment of about 1.25 cm backfat was attained. Days on feed were similar for all steers at 190 d. Feedlot ADG was similar for steers on SUP3 (1.36 kgּ d-1), PAS (1.34 kgּ d-1), and SUP6SR (1.29 kgּ d-1), but greater (P = 0.045) than steers on SUP6 (1.24 kg d-1). These feedlot ADG exhibited some compensatory gain effects from pasture treatments. Off feedlot weights were similar at 620 kg. Steers were transported 60 km to an abattoir for harvest and carcass trait evaluations. There were no differences across treatments for steer hot carcass weight, 367 kg; 12th rib fat thickness, 1.13 cm; marbling score, 395; calculated yield grade, 3.10; longissimus dorsi area, 85.02 cm2; or internal fat (kidney-pelvic-heart), 1.92%. With SUP:extra gain at 12.5:1 for SUP3 and 13.8:1 for SUP6, supplementation of whole corn for Brahman steers stocked on T85 was not as efficient as previous T85 x SUP experiments with DDGS, but may offer management options for specific cattle classes and ownership-stocking strategies.
PSXIII-6 Weed encroachment reduces soil organic carbon stock in bermudagrass pastures
Authors: Dubeux José C B , Brêtas Igor , Queiroz Luana , Kelly Courtland , Flynn Scott , Ingram Sam , Trumpp Kevin , Oduor Kenneth , Portuguez Javier , Bernardini Marilia , Ruiz-Moreno Martin
Published: September 2024

Weed encroachment might reduce stocking rate and overall animal performance in grazing systems. In addition, weeds can affect soil organic carbon because of changes in primary productivity and belowground biomass compared with well managed pastures. This study assessed different levels of spiny pigweed (Amaranthus spinosus L.) encroachment on bermudagrass [Cynodon dactylon (L.) Pers.] pastures. Spiny pigweed was drilled onto bermudagrass pastures to create three levels of encroachment: weed free, medium encroachment, and high encroachment. The weed-free pastures were treated with herbicide to control weed encroachment, and the medium had strips where weeds were controlled and strips uncontrolled. The high encroachment had no weed control. Treatments (weed free, medium, and high) were allocated in a randomized complete block design. The spiny pigweed was drilled in 2020 and grazing occurred from 2021 to 2023. Soil samples were collected in October 2023 to assess soil organic carbon (C) stock by determining soil bulk density and soil C concentration in the 0- to 5- and 5- to 15-cm layers. Results indicated that weed-free and medium-encroached pastures had greater soil organic carbon stock (20.2 Mg C/ha) compared with the weed-infested pastures (17.2 Mg C/ha). Soil C concentration was similar, but soil bulk density was lower in the weed-infested pastures, affecting soil carbon stocks.
PSVII-15 Interaction of supplemental rumen-protected lysine and methionine, and ractopamine-hydrochloride on cattle growth performance and carcass characteristics of finishing calf-fed Holstein steers
Authors: Carvalho Pedro H V , Latack Brooke C , Veaslquez Cesar , Moura Gustavo A B , Zinn Richard A A
Published: September 2024

The objective of the current study was to investigate the effects of supplemental rumen-protected lysine and methionine (SMART) and ractopamine-hydrochloride (RAC) on cattle growth performance and carcass characteristics of finishing calf-fed Holstein steers. Calf-fed Holstein steer calves [n = 96; body weight (BW) = 466 ± 29 kg] were used to evaluate the interaction of ractopamine and supplemental methionine and lysine on growth performance and carcass characteristics. Steers were blocked by initial off-truck BW and assigned within BW grouping to 16 pens (6 steers/pen). From d 1 to 67, all steers received the basal steam-flaked corn-based finishing diet. From d 68 to harvest (d 103), steers received experimental diets consisting of two levels of RAC (0 vs. 300 mg/hd/d; Optaflexx, Elanco US, Inc., Greenfield, IN) and two levels of supplemental SMART (0 vs. 0.67% DM basis, Smartamine ML Adisseo, Alpharetta, GA). There was an interaction (P = 0.04) between RAC and SMART supplementation, where cattle fed the combination of both supplements had an increase in dry matter intake (DMI) compared with cattle fed either RAC or SMART. However, there was no interaction (P ≥ 0.17) of treatments in other growth performance or carcass characteristic variables evaluated in the study. Carcass adjusted average daily gain (ADG) and energy efficiency of the diet increased (P ≤ 0.02) on cattle supplemented with SMART. Moreover, carcass-adjusted final BW and feed efficiency, as well as energy efficiency, increased (P ≤ 0.05) on cattle supplemented with RAC. However, neither SMART nor RAC supplementation affected (P ≥ 0.13) cattle DMI. Both SMART and RAC supplementation increased (P ≤ 0.03) carcass weight, with no effect (P ≥ 0.17) in other carcass characteristics. In conclusion, both SMART and RAC supplementation enhances cattle growth performance with no detrimental effects on carcass characteristics of calf-fed Holstein steers.
PSII-11 Temporal variables of the four-beat stepping gaits of the Mountain Pleasure Horse
Authors: Nicodemus Molly , North Ed , Culwell Robert , Ellsworth Sierra , Williams Toree
Published: September 2024

The Mountain Pleasure Horse (MPH) is the oldest gaited horse breed in North America with genetic testing finding the breed is ancestral to all other American gaited horse breeds according to the MPH Association (MPHA). Further, the breed is classified as “threatened” according to the Livestock Conservancy with only 2,670 purebred MPHs living today. To expand numbers, the registration books for the MPHA were opened in 2009; however, 5 yr later the books were closed due to negative consequences including potential changes within the gait. Therefore, to ensure the preservation of the gait of the MPH, the objective of this study was to define the temporal variables of the four-beat stepping gaits of the purebred MPH. The six horses utilized for this study were MPHA registered with permanent registration status and were verified to be purebred using blood typing and pedigree tracing with pedigrees tracing back to the foundation sires on both sides of the pedigree as identified by the MPHA. Horses were ridden by their respective trainers at a flat walk and saddle rack following MPHA judging guidelines with those strides utilized for the study being selected by representatives of the breed association. A total of 10 strides for each horse (n = 60) for each gait were selected. Student’s paired t-tests were utilized to determine differences in temporal variables between gaits with P-value set at 0.05. Comparisons were also made within gaits using student’s paired t-test to determine differences between lateral and diagonal variables. Both gaits had a lateral footfall pattern that alternated between bipedal and tripedal support. The saddle rack was performed at a faster velocity than the walk with a longer stride length and shorter stride and stance durations (Table 1). Advanced placements and bipedal support were similar between gaits with lateral and diagonal variables similar within gaits (Flat Walk Lateral-Diagonal Comparisons: Advanced Placement; P = 0.31, Bipedal Support; P = 0.08; Saddle Rack Lateral-Diagonal Comparisons: Advanced Placement; P = 0.23, Bipedal Support; P = 0.11), thus, indicating the gaits had a regular rhythm with no couplets. These variables assist in distinguishing between the gaits of the MPH and between those performed by other gaited horse breeds.
PSII-15 Comparative analysis of equine diets on growth metrics and economic feasibility
Authors: Blythe Madison K , Anderson Mark J , Nelson Tatum B , Flores Karla V , Beverly Marcy M M , Kelley Stanley F , Martinez Rafael E
Published: September 2024

The objective of the study was to assess the impact of two commonly available low non-structural carbohydrate equine diets on growth parameters and economic factors in young growing horses. To do this, young stock type horses n = 11; 6 fillies, 5 colts; body weight (BW) = 380.3 ± 15 kg] were separated into two groups that were balanced by age, sex, and BW. All horses were backgrounded for 14 d on a hay-only diet prior to the beginning of the study. Additionally, each group was assigned to one of two dietary treatments fed at 0.75% BW/d (as fed) twice daily in 12 h intervals for 56 d. Dietary treatments consisted of a leading national brand feed (n = 5) and Thomas Moore Calm and Safe (n = 6). Horses were allowed ad libitum access to Coastal bermudagrass (Cynodon dactylon) hay and fresh water. For the 56-d period, horses were exercised at a light workload for 30 min/d and 4 d/wk. For all growth measurements, a baseline measurement was recorded per horse. Growth measurements were then recorded at 7 d intervals. Data from these growth measurements were analyzed using PROC MIXED in SAS v9.4 with the fixed effects of day and diet. Growth metrics increased on all horses throughout the length of the trial regardless of dietary treatment (P ≤ 0.01), which is expected from young growing horses. A Diet x Day trend towards significance (P = 0.075) was observed for BW, as the leading national brand feed dietary treatment group tended to have heavier BW than the Thomas Moore Calm and Safe during the duration of the study. Additionally, body fat percentage was greater (P = 0.04) in the national leading brand feed group compared with the Thomas Moore group. None of the remaining growth metrics had any statistical difference across diets. Furthermore, there was no difference in dietary intake between dietary groups (P > 0.5). These results suggest that the Thomas Moore Calm and Safe concentrate serves as a good alternative and economically friendly for young growing horses when compared with more traditional feeds currently on the market.
PSII-9 Impact of exercise on blood metabolites and other health parameters during the reconditioning of emaciated stock-type horses
Authors: Maldonado Ashley M , Boyd Jamie A , Bardassi Ariane Tabari , Rosa Laura Patterson
Published: September 2024

In the equine industry, optimal and reduced-muscle-stress-inducing exercise levels are not well understood for horses recovering from negligence. To optimize equine recovery and welfare, this study delved into the effects of exercise among horses in rehabilitation from previous dietary neglect by evaluating blood biochemistry and health parameters. We conducted an 8-wk reconditioning study during Spring 2023, comprised of 9 horses assigned to one of the three diet groups: commercial low starch/sugar grain with Bermuda hay (Ctrl = 3), Total Equine extruded pellets with Bermuda hay (Trt = 3), and Total Equine extruded pellets only (Grn = 3). Horses were housed in 4.2 x 4.2m stalls, with access to ad libitum water, and exercised in a Priefert hot walker (Priefert Manufacturing, Mount Pleasant, TX) for 5 d/wk, with 2 d of stall rest. Exercise time gradually increased from 15 to 75 min/d through the 8 wk. Blood samples for biochemistry and immediate lactate measures, as well as clinical health parameters [body temperature (T); respiration rate (RR); and heart rate (HR)], were collected in wk 0, 4, and 8, during pre-exercise (baseline) and post-exercise at time = 0, 5, and 15 minutes. Data was analyzed using Proc Mixed procedures of SAS in a randomized block design considering week and individual horse. Diet had no impact on blood lactate (P > 0.50), RR (P = 0.08), HR, or T. The alkaline phosphatase (ALKP) and aspartate aminotransferase (AST) were significantly greater for the Grn when compared with the Ctrl and Trt groups (P ≤ 0.0001). These blood biochemistry health markers may indicate inflammation in the gastro-intestinal tract associated to the Grn diet. No significant impact on lactate and quick recovery of baseline health parameters indicate that the gradual increase and amount of exercise was likely adequate for this cohort of recovering horses. Further evaluation in other recovery horse groups is necessary to validate and establish a recommended exercise protocol for previously neglected horses in rehabilitation.
PSIII-30 Development of an application programming interface (API) to automate downloading and processing of precision livestock data
Authors: Parsons Ira L , Brennan Jameson R , Harrison Meredith A , Menendez Hector M
Published: September 2024

Advancements in technology have ushered in a new era of sensor-based measurement and management of livestock production systems. These sensor-based technologies have the ability to automatically monitor feeding, growth, and enteric emissions for individual animals across confined and extensive production systems. One challenge with sensor-based technologies is the large amount of data generated, which can be difficult to access, process, visualize, and monitor information in real time to ensure equipment is working properly and animals are utilizing it correctly. A solution to this problem is the development of application programming interfaces (APIs) to automate downloading, visualizing, and summarizing datasets generated from precision livestock technology. For this methods paper, we develop three APIs and accompanying processes for rapid data acquisition, visualization, systems tracking, and summary statistics for three technologies (SmartScale, SmartFeed, and GreenFeed) manufactured by C-Lock Inc (Rapid City, SD). Program R markdown documents and example datasets are provided to facilitate greater adoption of these techniques and to further advance precision livestock technology. The methodology presented successfully downloaded data from the cloud and generated a series of visualizations to conduct systems checks, animal usage rates, and calculate summary statistics. These tools will be essential for further adoption of precision technology. There is huge potential to further leverage APIs to incorporate a wide range of datasets such as weather data, animal locations, and sensor data to facilitate decision-making on times scales relevant to researchers and livestock managers.
PSLBI-8 Effect of sunflower (Tithonic diversifolia) extract on growth performance and serum antioxidant enzymes of broiler chickens
Authors: Ogunkunle Funmilola , Alade Oluwatooyin , Ogunkunle Nathaniel
Published: September 2024

The ban of antibiotic growth promoters in many countries has increased the use of plant bioactives as alternatives to antibiotics; however, there is little information on the impact of sunflower extract on animal performance. Therefore, this study focused on the use of sunflower extract on growth performance and serum antioxidant enzymes of broiler chickens. Unsexed broiler chicks (n = 128; 1 d of age) were completely randomized into group 1 (Con: 0 mL of extract; n = 32), group 2 (2SE: 2mL/L of extract, n = 32), group 3 (4SE: 2mL/L of extract; n = 32) and group 4 (6SE: 2mL/L of extract; n = 32). Each group was replicated 4 times with 8 chicks per replicate. Data was analyzed as one-way ANOVA using SAS 9.4 at 5% alpha. There was no significant (P = 0.0605) difference in final body weight (BW), BW gain (P = 0.0557) and average daily gain of the chickens. The BW gain was 1,727.54g, 1,970.87g, 1,913.86 g and 1,765.53 g for CON, 2SE, 4SE and 6SE respectively. There was significant (P < 0.05) difference in superoxide dismutase and glutathione peroxidase while no significant difference was observed in catalase enzyme activity. In conclusion, sunflower extract could increase the antioxidant status of broiler chickens by scavenging free radicals, it has the potential to increase growth performance, thereby increasing broiler productivity and welfare.
PSLBI-29 Gene expression patterns in liver tissue proximal to abscesses in cattle
Authors: Baker Emilie C , Lawrence Ty E
Published: September 2024

Liver abscesses pose a significant economic burden on the beef industry, resulting in substantial profit losses. A contributor to these losses is the decreased productivity and feed efficiency observed in affected cattle. Reduced feed efficiency could be attributed to the impairment of metabolic activity due to liver tissue damage caused by the abscesses. While tissue within the abscess itself is dysfunctional, little is known about the functional state of the surrounding liver tissue. Considering this, the present research aimed to evaluate liver tissue gene expression profiles at varying distances from liver abscesses. Tissue samples (n = 21) were collected from three distinct regions: 1) <4 mm proximal from the abscess without including abscessed tissue (adjacent tissue), 2) 3 cm proximal from the abscess (nearby tissue), and 3) from livers with no abscesses (healthy controls). Gene expression comparisons utilizing DESeq were conducted between each tissue sample group. The number of differentially expressed genes (FDR ≤ 0.10) identified in each comparison is presented in Table 1. Tissue directly adjacent to the liver abscess was substantially different in gene expression when compared with both the healthy and tissue 3 cm proximal to an abscess. Fewer genes exhibited differential expression between healthy tissue and tissue taken 3 cm away. Gene enrichment analysis was conducted using the KOBAS-i software to identify biological pathways associated with the differentially expressed genes. Genes upregulated in liver tissue adjacent to the abscess were associated (FDR ≤ 0.10) with immune response pathways, including the “T cell receptor signaling pathway” and “Cytokine-Cytokine receptor interaction,” whereas downregulated genes were linked to metabolic pathways such as “Fatty Acid Metabolism” and multiple amino acid biosynthesis pathways. Gene expression differences between tissue 3 cm away and healthy tissue were minimal; however, enrichment analysis identified significant (FDR ≤ 0.10) metabolic pathways such as the “peroxisome proliferator-activated receptor signaling” which is involved in gluconeogenesis and lipid metabolism, suggesting some metabolic alterations up to 3 cm proximal from the abscess. Upregulation of immune response pathways and downregulation of metabolic pathways in the adjacent tissue suggest a shift in cellular priorities, diverting resources to combat the active infection rather than routine metabolic processes. This localized immune response and metabolic dysregulation observed in the liver tissue adjacent to the abscess, coupled with metabolic alterations up to 3 cm away, highlight the effects of liver abscesses on the overall metabolic capacity and functionality of the liver. Continued research should focus on investigating the effect of abscess severity on overall liver function.
PSLBI-17 Total sulfur amino acid requirements across the canine life cycle in Labrador Retrievers using the indicator amino acid oxidation (IAAO) technique
Authors: Dickerson Sarah M , Timlin Claire L , McCracken Fiona B , Fowler Jason W , coon craig n
Published: September 2024

Methionine and cysteine are the principal sulfur-containing amino acids that are incorporated into proteins, although homocysteine and taurine also have important physiological roles in canines. As limited studies have been conducted for total sulfur-containing amino acids (TSAA) requirements across the canine life cycle, our objective was to determine the minimum requirements (MR) for TSAA at 4 life stages using the indicator amino acid oxidation (IAAO) technique. Labrador Retrievers (n = 24) were used in feeding studies to evaluate the changing requirements of TSAA as dogs mature: 6 puppies aged 10 to 14 wk, 6 puppies >14 wk to 9 mos, 6 adults 2 to 5 yr (yr), and 6 seniors > 8yr. Following a 2-d adaptation to a TSAA-adequate basal diet (TSAA = 1.12% dry matter), dogs underwent individual IAAO studies. In brief, all dogs were randomly fed one of six test diets with varying levels of TSAA ranging from deficient to sufficient (final TSAA content in experimental diets were 0.41, 0.46, 0.51, 0.98, 1.05, and 1.12% dry matter, with indispensable amino acids formulated at 1.6x NRC values). The test diet was divided into 13 equal meals; at the 5th meal, a tracer amino acid was included (a bolus L-[1-13C] phenylalanine based on body weight was first given, followed by [1-13C] Phe doses every 30 spanning 4 h). Breath samples were collected via a respiration mask every 30 min. Total CO2 production was determined via indirect calorimetry and production of 13CO2 at each dose was measured by enrichment of 13C in breath samples via isotope ratio mass spectrometry (IRMS). Results for IRMS data were converted to atom percent excess (APE) and analyzed using segmented linear regression. The Four Rivers mean and population requirements for TSAA were estimated to be 1.55 ± 0.069 g/1,000 kcal (mean ± 2 SD) for puppies 10 to 14 wk, 1.53 ± 0.21 g/1,000 kcal (mean ± 2 SD) for puppies 14 wk to 9 mo, 1.4 ± 0.30 g/1000 kcal (mean ± 2 SD) for adults 2 to 5 yr, and 1.27 ± 0.23 g/1,000 kcal (mean ± 2 SD) for seniors. These results may contribute to the formulation of diets that meet the age-appropriate requirements of TSAA for large-breed dogs at all life stages.
PSLBI-18 Isoleucine requirements of young adult and senior Labrador retrievers
Authors: Dickerson Sarah M , Fuqua Mary E , Webb Tanya , Timlin Claire L , McCracken Fiona B , Fowler Jason W , Coon Craig N
Published: September 2024

Age-appropriate diets that meet the unique nutritional needs of aging are in greater demand as senior dogs represent an increasing percentage of the pet population. Studies targeting the specific amino acid requirements of the aging canine are important because they may inform dietary formulations for this specific life stage. In this study, the indicator amino acid oxidation (IAAO) technique was used to determine the minimum requirements for isoleucine (Iso) in young adult and senior Labrador retrievers. After 2-d adaptation to Iso-adequate basal diet (Iso = 0.608% dry matter), dogs underwent individual IAOO studies. In brief, all dogs were randomly fed one of six test diets with varying levels of isoleucine ranging from deficient to sufficient (final Iso content in experimental diets were 0.244, 0.285, 0.326, 0.532, 0.57 and 0.608% dry matter). Test diet was divided into 13 equal meals; at the 5th meal, a tracer amino acid was supplied (a bolus L-[1-13C] phenylalanine based on body weight was first given, followed by [1-13C] Phe doses every 30 min spanning a 4 h period), and breath samples were collected via respiration mask every 30 min. CO2 production was determined via indirect calorimetry and production of 13CO2 at each dose was measured by enrichment of 13C in breath samples via isotope ratio mass spectrometry (IRMS). Results for IRMS data were converted to atom percent excess (APE) and analyzed using segmented linear regression. The Four Rivers mean and population requirements for isoleucine were 898 ± 71 mg/1,000 kcal ME (mean ± 2 SD) for young adults and 885 ± 91 mg/1,000 kcal ME (mean ± 2 SD) in senior dogs, which is slightly greater than the National Research Council’s minimum requirement. As the pet food industry offers more specialized diets for aging canines, updating the amino acid requirements for such animals is increasingly important.
PSLBI-1 Stepwise approach applied to metabolites related to residual feed intake in Angus cattle
Authors: Ten Nunes Alanne ório , de Novais Francisco José , Faleiros Camila Aparecida , Marcilli Gabriela Marques , Poleti Mirele Daiana , Ferraz José Bento Sterman , Fukumasu Heidge
Published: September 2024

Feed efficiency (FE) selection is crucial for improving the economic and environmental sustainability of beef cattle production. Residual feed intake (RFI) is the most commonly used parameter for FE because it is independent of metabolic body weight (MBW) and average daily gain (ADG). Low-RFI (LRFI) animals are more efficient, as they present less feed intake than expected, decreasing dry matter intake (DMI) and methane production per unit of body weight gain (BW). However, considering the time and resources required for RFI measurement, omics methods have been applied to distinguish between LRFI and high-RFI (HRFI) animals. This study performed a stepwise approach as an alternative for selecting important plasma metabolites related to RFI in beef cattle. Black Angus bulls (n = 64) with an initial BW of 321.8 ± 59.98 kg and 12.9 ± 1.08 mo from rearing under continuous grazing were allocated to feedlot pens and fed a diet containing 80:20 roughage:concentrate. The animals were evaluated for DMI and BW using an integrated real-time data collection system (Intergado, Brazil) for 56 d, and ADG was estimated as the slope of the linear regression between BW and days on feed. Blood samples were collected at the end of the finishing phase by puncturing the coccygeal vessels. Through targeted metabolomics, concentrations of plasma amino acids, biogenic amines, and hexoses were determined using an AB Sciex 5500 QTRAP mass spectrometer in liquid chromatography-mass-spectrometry and flow-injection analysis mode. The fixed effect of MBW, ADG, age and batch, and the random effect of sire were considered in the mixed model to determine RFI and to categorize the 20 greatest and 20 least values as HRFI and LRFI, respectively, using the lmer4 R package. A stepwise approach in both directions was used in the MASS R package. The model with the lowest AIC (31.15) presented 23 of the 31 metabolites, followed by ANOVA (Table 1). Serotonin, glutamate, phenylalanine, and tyrosine concentrations were greater in HRFI, whereas aspartate, citrulline, tryptophan, ornithine, taurine, creatinine, and trans-4-hydroxyproline concentrations were greater in LRFI (P < 0.05). The gluconeogenic potential of glutamate, phenylalanine, and tyrosine suggests that an impact on energy availability may affect DMI. Conversely, differences in creatinine and trans-4-hydroxyproline abundance can reflect changes in muscular body mass, while the greater concentrations of aspartate, citrulline, and ornithine in LRFI animals suggest that a lower DMI can be associated with lower urea cycle activity. The stepwise approach appears to be a feasible alternative as a pre-selection method to identify plasma metabolites that could be used to categorize beef cattle for RFI. Further validation is required to confirm the potential of these metabolites as biomarkers for FE selection.