Cattle Fed Research Articles

Were consumers of plant-based beef substitutes buyers of organic or grass-fed beef? Insights from correlations in willingness to pay

Organic and grass-fed beef serve as niche alternatives to conventionally grain-fed beef. A recent addition is plant-based beef substitutes, all three of which are marketed as environmentally friendly options. Despite this, it remains uncertain which specific products plant-based beef substitutes are most directly competing with. In this study, we investigate the correlations between the willingness to pay for plant-based beef substitutes and organic/grass-fed beef using a choice experiment and the Willingness to Pay Space model. Our findings indicate positive correlations between consumers' preferences for plant-based, organic, and grass-fed beef. This suggests that plant-based beef consumers are more likely to be prior consumers of organic or grass-fed beef. Given their relatively small market shares, novel beef substitutes could pose intense competition to the ecolabeled products.

Prevalence and concentration of mycotoxins in bovine feed and feed components: A global systematic review and meta-analysis

Mycotoxins are secondary metabolites produced by fungi and identified as contaminants in animal feed. They have potentially harmful effects, including carcinogenicity, mutagenicity, and repro-toxicity in animals and humans. As a result of climate change, there is the potential for a change in the prevalence and concentration of mycotoxins in animal feed components. This necessitates an assessment of the present and emerging threats to the food supply chain from mycotoxins. This systematic review and meta-analysis study synthesised studies on mycotoxin contamination and prevalence in cattle feed components. The studies were collected from scientific databases Web of Knowledge, Scopus, and Embase between 2011 and 2022. The meta-analysis synthesised 97 studies on the prevalence and the concentration of aflatoxins, ochratoxin A, deoxynivalenol, zearalenone, fumonisin and T-2/HT-2 toxins in feed components. Aflatoxin was highly prevalent (59 %), with a concentration of 2.58–3.92 μg kg−1 in feed components. Ochratoxin A had a global prevalence of 31 % with a concentration of 5.56–12.41 μg kg−1. Deoxynivalenol had a global concentration of 233.17–327.73 μg kg−1 and a prevalence of 74 %. Zearalenone had a prevalence of 70 % and a concentration of 42.47–66.19 μg kg−1. The concentration and prevalence of fumonisins was 232.19–393.07 μg kg−1 and 65 %, respectively. The prevalence and concentration of T-2/HT-2 toxins were 45 % and 23.54–35.12 μg kg−1, respectively. The synthesised concentration of the mycotoxins in the overall feed components was lower than the regulated and guidance values set by the European Union. However, in a few cases, the 95th percentile exceeded these concentration values due to high levels of uncertainty attributed to lower sample size, and thus, need to be considered while conducting risk assessments. The study highlights climates and regions likely to be conducive to the emergence of mycotoxin risk, especially considering the potential influences of climate change.

POTENTIAL OF CATTLE FEED FROM PALM OIL LEAVES AND MIDRIBS USING THE FERMENTATION PROCESS IN WEST KALIMANTAN

Abstract: One of the most crucial phases of cattle farming is the supply of high-quality animal feed, which can enhance productivity and animal health. Animal feed is often a problem in West Kalimantan. However, this area is an oil palm plantation, so it has the potential to produce oil palm waste. This community service activity aims to increase knowledge and practice community skills in oil palm plantations in utilizing palm oil waste in cattle feed. The community service applied a socialization and training methods to make high-quality fermented animal feed using palm oil waste, namely leaves and fronds. Participants in this program included the village chief and the village's livestock owners, a total of 30 people. The farmers benefited from the results of this training and socialization. The villagers can use palm leaves and fronds to make fermented animal feed. This adds insight into how to improve livestock productivity and health. In addition, this activity also has the potential to reduce the amount of palm oil waste generated, in addition to increasing the economic value of the waste. The results of the feed processing technology service activities after socialization and training were carried out, there was an increase in participants' knowledge regarding understanding feed processing, post-test scores from 33% to 80% after the post-test, and post-test scores on feed processing practices from 40% to 80% after the post-test.

Mucosal Immunization with Spore-Based Vaccines against Mannheimia haemolytica Enhances Antigen-Specific Immunity.

Mannheimia haemolytica is a bovine respiratory pathogen commonly associated with bacterial bronchopneumonia. Current vaccine strategies have shown variable efficacy in feedlot cattle, and therefore novel vaccines are needed. Bacillus subtilis spores have been investigated as a mucosal vaccine platform, due to their ability to bind and present antigens to the mucosa and act as an adjuvant. The aim of this study was to develop two spore-based mucosal vaccines targeting M. haemolytica and evaluate their immunogenicity in mice. Two antigen constructs composed of cholera toxin B subunit, M. haemolytica leukotoxin, and either the M. haemolytica outer membrane protein PlpE (MhCP1) or GS60 (MhCP2) were synthesized, purified and then bound to spores as vaccines. In two separate mice trials, the spore-bound vaccines (Spore-MhCP1 and Spore-MhCP2) were administered to mice through intranasal and intragastric routes, while free antigens were administered intranasally and intramuscularly. Unbound spores were also evaluated intranasally. Antigen-specific serum IgG and mucosal IgA from bronchoalveolar lavage, feces, and saliva were measured after vaccination. Mice sera from all treatment groups were assessed for their bactericidal activity against M. haemolytica. In both mice experiments, intramuscular immunization induced the strongest serum IgG antibody response. However, the intranasal administration of Spore-MhCP1 and Spore-MhCP2 elicited the greatest secretory IgA-specific response against leukotoxin, PlpE, and GS60 in bronchoalveolar lavage, saliva, and feces (p < 0.05). Compared to the intranasal administration of free antigen, spore-bound antigen groups showed greater bactericidal activity against M. haemolytica (p < 0.05). Since intranasally delivered Spore-MhCP1 and Spore-MhCP2 elicited both systemic and mucosal immune responses in mice, these vaccines may have potential to mitigate lung infection in cattle by restricting M. haemolytica colonization and proliferation in the respiratory tract. The efficacy of these mucosal spore-based vaccines merits further assessment against M. haemolytica in cattle.

ARCH/GARCH Analysis: Estimating Beef Price Volatility in Indonesia

This study analyses the volatility of beef prices in Indonesia, a strategic commodity that significantly impacts the welfare of producers and consumers. The sustained and erratic price fluctuations pose an economic risk to producers and threaten farmers' economic stability. ARCH / GARCH models were used to analyze daily beef price data from 10 July 2017 to 31 December 2023, obtained from the National Strategic Food Price Information Centre of Bank Indonesia. The GARCH (2,2) model is the most suitable for estimating the volatility of beef prices in Indonesia, with low and sustainable volatility in the long run. Factors that affect this volatility include feeder cattle and beef imports, exchange rates, livestock diseases, the COVID-19 pandemic, and government policies such as PPKM and PSBB during the new normal era. Important events such as Ramadan, Eid al-Fitr, Christmas, and New Year also influence price volatility of beef. This research aims to assist the government to design more effective market stabilization policies in the short, medium, and long term period. Keywords: beef, ARCH/GARCH, price volatility, fluctuation

Epidemiology of Digital Dermatitis in Western Canadian Feedlot Cattle.

Digital dermatitis (DD) is an emerging disease in feedlot cattle. Our objective was to identify animal- and feedlot-level risk factors for DD by analyzing individual animal health records (n = 1,209,883) and feedlot-level records from western Canadian feedlots (n = 28) between 2014 and 2018, inclusive. The risk of a DD diagnosis was higher (incidence rate ratio (IRR) = 2.08, 95% CI 1.52 to 2.86) in cattle sourced from confined background operations (CB) versus cattle sourced from auction markets (AM). Conversely, ranch direct (RD) cattle were (IRR = 0.02, 95% CI 0.04 to 0.30) lower risk than AM cattle of being diagnosed with DD. The risk of being diagnosed with DD was higher in females than in males. The magnitude of the risk in females over males was influenced by annual DD incidence in low morbidity years (2014, 2017, and 2018) (IRR = 2.02, 95% CI 1.27 to 3.19), medium morbidity years (2016) (IRR = 2.95, 95% CI 1.64 to 5.33), and high morbidity years (2015) (IRR = 5.41, 95% CI 3.27 to 8.95). At the feedlot-level, the risk of a diagnosis of DD was lower in small capacity (SCF) versus large capacity feedlots (LCF) (IRR = 0.24, 95% CI 0.05 to 0.76). Future research should focus on identifying factors that may propagate disease transmission between cattle of different sexes and from different acquisition sources.

Use of probiotic lactobacilli as alternative to monensin in beef feedlot cattle

Use of probiotic lactobacilli as alternative to monensin in beef feedlot cattle

Level of aflatoxins in dairy feeds, poultry feeds, and feed ingredients produced by feed factories in Addis Ababa, Ethiopia.

Aflatoxins are one of the major factors that affect the quality and safety of feeds. They can be transferred into livestock through contaminated feed and then onto humans via animal sources of food such as milk, meat, and eggs. The objective of this study was to detect and quantify the level of aflatoxins (B1, B2, G1, G2, and total aflatoxin) in dairy feeds, poultry (layer and broiler) feeds, and feed ingredients produced in Addis Ababa. A total of 42 feeds and feed ingredients consisting of dairy feeds (n = 5), poultry broiler feeds (n = 6), layer feeds (n = 6), and feed ingredients (n = 25) were collected from feed factories in the city and analyzed in fresh weigh basis. The aflatoxins were analyzed using high-performance liquid chromatography after clean-up with immunoaffinity columns. Aflatoxin B1 levels in feeds ranged from 51.66 to 370.51µg/kg in dairy cattle feed, from 1.45 to 139.51µg/kg in poultry layer feed, and from 16.49 to 148.86µg/kg in broiler feed. Aflatoxin B1 levels in maize ranged from 2.64 to 46.74µg/kg and in Niger seed cake from 110.93 to 438.86µg/kg. Aflatoxin B1 levels in wheat bran, wheat middling, and soybean were below 5µg/kg. 100% of dairy feeds, 67% of poultry layer, 67% of broiler feeds, and 24% of ingredients contained aflatoxin in levels higher than the maximum tolerable limit set by the US Food and Drug Administration and Ethiopian Standard Agency. This shows the need for strong regulatory monitoring and better feed management practices to prevent consumers of animal-source foods from significant health impacts associated with aflatoxins.

Genetic characteristics of Blastocystis sp. in cattle from Hebei Province, China

Blastocystis sp. is a protozoan parasite that infects the intestines of humans and animals, causing chronic diseases such as skin rashes, abdominal pain, and irritable bowel syndrome. A survey was conducted to determine the prevalence and genetic diversity of Blastocystis sp. infection in cattle, in Hebei Province, China. 2746 cattle fecal samples were collected from 11 cities in Hebei Province and analyzed using polymerase chain reaction targeting the Blastocystis sp. barcoding gene. MEGA, PhyloSuite, and PopART were used to analyze the subtype, sequence signature, pairwise genetic distance, and genetic diversity indices. The results showed that the Blastocystis sp. detection rate was 12.60% (346/2746). The infection rate in different herds was affected by region, age, breeding mode, and variety; that is, the infection rates in areas of southern Hebei, cattle under one year old, intensive raising, and dairy cattle were higher than the infection rates in northern Hebei, cattle over one year old, scatter feeding, and beef cattle. Seven Blastocystis subtypes were identified, namely, ST1, ST2, ST5, ST10, ST14, ST21, and ST26; ST10 was the dominant subtype, and ST14 was the second most common subtype. A total of 374 polymorphic and conserved sites were obtained, including 273 invariable (monomorphic) sites and 101 variable (polymorphic) sites, accounting for 27.01% of all nucleotides. The nucleotide diversity index (Pi) was 0.07749, and the haplotype (gene) diversity index (Hd) was 0.946. This study provides the first comprehensive information on the epidemiological situation of Blastocystis sp. infection in cattle from Hebei Province, China, and revealed rich genetic diversity of Blastocystis sp.

Biomass Densification to Improve Management Efficiency and to Obtain High Value Products in México

In México, the utilization of fast-growing plant species for biomass production presents transportation-related issues such as freshness reduction, the transportation of large volumes with minimal weight due to low density, limited storage availability, and logistical challenges. To enhance understanding in this field, the research aimed to evaluate the densification potential of a variety of organic materials, with a specific emphasis on the biomass derived from eight species of rapidly growing plants, three animal species’ manure, and concentrated feed. After conditioning, 100 g samples underwent particle size analysis and were categorized into seven sizes. Pellets and briquettes (40 g, 10% moisture, 15 MPa pressure, 5 min processing, 80 °C temperature) were produced and evaluated for bulk density (BD) and pellet (PD) and briquette durability (BDU). The predominant particle sizes were 0.850 mm and 0.425 mm. Original biomass bulk density (OBBD) varied notably, with ovine manure (0.50 g cm−3) and cattle feed (0.49 g cm−3) exhibiting the highest values. Caprine manure (0.83 g cm−3) and ovine manure (0.78 g cm−3) yielded the densest pellets at 1.76 and 1.84 g cm−3, respectively. Apple tree pellets achieved premium quality with the highest hardness (97.9%). Cattle manure (1.25 g cm−3) and cattle feed (1.25 g cm−3) had the densest briquettes, with notable BBD/OBBD ratios in pine sawdust (4.6) and corn (4.5). Caprine manure and Acacia biomass briquettes showed premium quality with the highest hardness (99.1%), emphasizing densification variations and the need for tailored approaches based on organic material characteristics.

First Record of Tricolored Blackbirds in Idaho

Over 99% of Tricolored Blackbirds (Agelaius tricolor) occur in California. However, small populations persist in Oregon, Washington, Nevada, and Baja California. Loss of wetlands that historically served as foraging and breeding habitat has led to their increasing use of agricultural landscapes including silage fields and cattle feedlots. Here we provide the first documentation of the Tricolored Blackbird in Idaho (26 March–13 May and 3 November–16 December 2023), of up to 30 birds observed at five different locations associated with cattle feedlots, each 10–15 km apart, in Payette and Gem counties. Seven observations included recordings of vocalizations (3-23 April and 14 December 2023), largely coinciding with the final observations at each location, presumably before dispersal to breeding grounds. We consider three hypotheses to explain the apparently sudden occurrence of these birds, including their return to some of the same sites in November 2023: (1) a continued pattern of range expansion due to climate change; (2) an undetected long-term population due to low survey effort; or (3) a large-scale movement in response to flooding and extreme weather in the traditional range. We encourage continued monitoring and surveying of these locations in the coming years and surveying for both new wintering locations and for evidence of the Tricolored Blackbird breeding in Idaho.

ANALISIS PENGENDALIAN KUALITAS MENGGUNAKAN METODE SIX SIGMA DI PT CHEIL JEDANG FEED AND CARE - PLANT SERANG

PT Cheil Jedang Feed And Care - Plant Serang is a company that operates in the field of cattle feed manufacturing and produces three kinds of feed for cattle: poultry feed, shrimp feed, and aqua feed. (pakan ternak ikan). With a production capacity of 271,308 per year. By 2022, it was 224.991,45 tons, with a defective number of 1.540,30 tons, or the equivalent of 0,7% of total production. In an effort to minimize the result of the defective product that occurs when the production process takes place in a company, a company needs strong commitment in carrying out the quality control process. The DMAIC method is used and assisted by some tools based on the existing data, and then improvement can be done with the six-sigma methodology that includes define, measure, analyze, improve, and control. After the improvement has been achieved, there is a decrease in the number of teams implementing the DMAIC method. It can be clearly seen that the original defect in the course of the year 1 January to December 2022 reached 1.540,30 MT of total production of 224.991,45 MT, which is 0,7% of the produced defect, and the path has passed the tolerance limit established by the company of 0.6%. After implementation of the method, DMAIC gives very significant results. Such things can be observed by reducing the defect number by 0.3% of the total production of 65.300,15 MT, even though it has not been implemented during the year from January to August 2023

Assessment Environmental and Social Impacts for the Rice Straw Utilization Technical Models to Promote Circular Economy for Rice Production in Chau Thanh District - An Giang Province

The study objective is to provide an initial scientific basis for calculating CO2 equivalent (CO2e) emission reduction from the three technical models such as rice-straw composting, rice-straw fermented for cattle feed, and straw mushroom production, which are rice-straw utilization alternatives instead of open burning them in Chau Thanh district. The study calculation is based on the surveyed practical database, the theoretical emission factors (EF), and the implementation of EasyPol-Ex software version 5 (Ex-Act) to estimate the amount of CO2e emissions when switching. The results show that in 2022, Chau Thanh could avoid 330,236 tons of CO2 emissions by burning 171,637 tons of rice straw. The estimated amount of CO2 emitted from harvesting and rolling rice straw by machine was 4.375 g CO2e per kilogram of rice straw. The EF for transportation of rice straw to model implementation places was 740 gCO2e/kg. The additional EFs for mushroom, composting, and animal feed production models were 222g, 172g and 60g CO2e/kg, respectively. Results indicate that although the EF of rice straw collection and transportation was still high, the total CO2e from three models (including transportation) was still lower than the EF from straw burning. In addition, farmers who own the paddy field earned an extra 500,000 VND/ha per crop, and farmers earned an extra about 1.7 to 2.3 million VND per crop, depending on the model applied. The successful implementation of technical models promoted the concept of circular economy applied to rice production industries.

Ruminal Microbiome Differences in Angus Steers with Differing Feed Efficiencies during the Feedlot Finishing Phase.

The catabolic activity of the ruminal microbial community of cattle enables the conversion of low-quality feedstuffs into meat and milk. The rate at which this conversion occurs is termed feed efficiency, which is of crucial importance given that feed expenses account for up to 70% of the cost of animal production. The present study assessed the relationship between cattle feed efficiency and the composition of their ruminal microbial communities during the feedlot finishing period. Angus steers (n = 65) were fed a feedlot finishing diet for 82 days and their growth performance metrics were evaluated. These included the dry matter intake (DMI), average daily gain (ADG), and residual feed intake (RFI). Steers were rank-ordered based upon their RFI, and the five lowest RFI (most efficient) and five highest RFI (least efficient) steers were selected for evaluations. Ruminal fluid samples were collected on days 0 and 82 of the finishing period. Volatile fatty acids (VFA) were quantified, and microbial DNA was extracted and the 16S rRNA gene was sequenced. The results showed that the ADG was not different (p = 0.82) between efficiency groups during the 82-day feedlot period; however, the efficient steers had lower (p = 0.03) DMI and RFI (p = 0.003). Less-efficient (high RFI) steers developed higher (p = 0.01) ruminal Methanobrevibacter relative abundances (p = 0.01) and tended (p = 0.09) to have more Methanosphaera. In high-efficiency steers (low RFI), the relative abundances of Ruminococcaceae increased (p = 0.04) over the 82-day period. The molar proportions of VFA were not different between the two efficiency groups, but some changes in the concentration of specific VFA were observed over time. The results indicated that the ruminal microbial populations of the less-efficient steers contained a greater relative abundance of methanogens compared to the high-efficiency steers during the feedlot phase, likely resulting in more energetic waste in the form or methane and less dietary energy being harvested by the less-efficient animals.

Lacticaseibacillus pabuli sp. nov., isolated from fermented cattle feed.

Strain BSF-3MT is a Gram-stain-positive, non-flagellated, facultative anaerobic and rod-shaped bacterium that was isolated from fermented feed collected at a cattle farm in the Daejeon region of the Republic of Korea. It was studied using polyphasic taxonomic methods. Using 16S rRNA gene sequences and the resulting phylogenetic tree, the strain was primarily identified as a member of the genus Lacticaseibacillus. Strain BSF-3MT contained a chromosome of 2.5 Mbp and a plasmid of 33.4 kbp. The G+C content of genomic DNA was 51.3 mol%. Strain BSF-3MT had the highest ortho-average nucleotide identity value of 73.7 % with Lacticaseibacillus songhuajiangensis 7-19T, its closest relative in the phylogenetic tree based on the 16S rRNA gene sequences and the phylogenomic tree based on up-to-date bacterial core genes. Based on the results of a polyphasic taxonomic study, strain BSF-3MT represents a novel species in the genus Lacticaseibacillus, for which the name Lacticaseibacillus pabuli sp. nov. is proposed. The type strain is BSF-3MT (=KACC 23028T=NBRC 116014T).

Association of ARRDC3 and NFIA variants with bovine congestive heart failure in feedlot cattle.

Bovine congestive heart failure (BCHF) has become increasingly prevalent among feedlot cattle in the Western Great Plains of North America with up to 7% mortality in affected herds. BCHF is an untreatable complex condition involving pulmonary hypertension that culminates in right ventricular failure and death. Genes associated with BCHF in feedlot cattle have not been previously identified. Our aim was to search for genomic regions associated with this disease. A retrospective, matched case-control design with 102 clinical BCHF cases and their unaffected pen mates was used in a genome-wide association study. Paired nominal data from approximately 560,000 filtered single nucleotide polymorphisms (SNPs) were analyzed with McNemar's test. Two independent genomic regions were identified as having the most significant association with BCHF: the arrestin domain-containing protein 3 gene ( ARRDC3), and the nuclear factor IA gene ( NFIA, mid- p-values, 1x10 -8 and 2x10 -7, respectively). Animals with two copies of risk alleles at either gene were approximately eight-fold more likely to have BCHF than their matched pen mates with either one or zero risk alleles at both genes (CI 95 = 3-17). Further, animals with two copies of risk alleles at both genes were 28-fold more likely to have BCHF than all others ( p-value = 1×10 -7, CI 95 = 4-206). A missense variant in ARRDC3 (C182Y) represents a potential functional variant since the C182 codon is conserved among all other jawed vertebrate species observed. A two-SNP test with markers in both genes showed 29% of 273 BCHF cases had homozygous risk genotypes in both genes, compared to 2.5% in 198 similar unaffected feedlot cattle. This and other DNA tests may be useful for identifying feedlot animals with the highest risk for BCHF in the environments described here. Although pathogenic roles for variants in the ARRDC3 and NFIA genes are unknown, their discovery facilitates classifying animals by genetic risk and allows cattle producers to make informed decisions for selective breeding and animal health management.

Selenized lactic acid bacteria microencapsulated by spray drying: A promising strategy for beef cattle feed supplementation.

This study aimed to assess the technical feasibility of incorporating selenized Lactobacillus spp. microencapsulated via spray drying into cattle feed. Gum Arabic and maltodextrin were used as encapsulating agents. The encapsulation process was carried out with a drying air flow rate of 1.75m3/min, inlet air temperature of 90°C, and outlet air temperature of 75°C. The viability of the encapsulated microorganisms and the technological characteristics of the obtained microparticles were evaluated. Microorganisms were incorporated into beef cattle feed to supplement their diet with up to 0.3mg of Se per kilogram of feed. The encapsulated particles, consisting of a 50/50 ratio of gum Arabic/maltodextrin at a 1:20 proportion of selenized biomass to encapsulant mixture, exhibited superior technical viability for application in beef cattle feed. Supplemented feeds displayed suitable moisture, water activity, and hygroscopicity values, ensuring the preservation of viable microorganisms for up to 5months of storage, with an approximate count of 4.5logCFU/g. Therefore, supplementing beef cattle feed with selenized and microencapsulated lactic acid bacteria represents a viable technological alternative, contributing to increased animal protein productivity through proper nutrition.

An across breed, diet and tissue analysis reveals the transcription factor NR1H3 as a key mediator of residual feed intake in beef cattle

BackgroundProvision of feed is a major determinant of overall profitability in beef production systems, accounting for up to 75% of the variable costs. Thus, improving cattle feed efficiency, by way of determining the underlying genomic control and subsequently selecting for feed efficient cattle, provides a method through which feed input costs may be reduced. The objective of this study was to undertake gene co-expression network analysis using RNA-Sequence data generated from Longissimus dorsi and liver tissue samples collected from steers of two contrasting breeds (Charolais and Holstein-Friesian) divergent for residual feed intake (RFI), across two consecutive distinct dietary phases (zero-grazed grass and high-concentrate). Categories including differentially expressed genes (DEGs) based on the contrasts of RFI phenotype, breed and dietary source, as well as key transcription factors and proteins secreted in plasma were utilised as nodes of the gene co-expression network.ResultsOf the 2,929 DEGs within the network analysis, 1,604 were reported to have statistically significant correlations (≥ 0.80), resulting in a total of 43,876 significant connections between genes. Pathway analysis of clusters of co-expressed genes revealed enrichment of processes related to lipid metabolism (fatty acid biosynthesis, fatty acid β-oxidation, cholesterol biosynthesis), immune function, (complement cascade, coagulation system, acute phase response signalling), and energy production (oxidative phosphorylation, mitochondrial L-carnitine shuttle pathway) based on genes related to RFI, breed and dietary source contrasts.ConclusionsAlthough similar biological processes were evident across the three factors examined, no one gene node was evident across RFI, breed and diet contrasts in both liver and muscle tissues. However within the liver tissue, the IRX4, NR1H3, HOXA13 and ZNF648 gene nodes, which all encode transcription factors displayed significant connections across the RFI, diet and breed comparisons, indicating a role for these transcription factors towards the RFI phenotype irrespective of diet and breed. Moreover, the NR1H3 gene encodes a protein secreted into plasma from the hepatocytes of the liver, highlighting the potential for this gene to be explored as a robust biomarker for the RFI trait in beef cattle.

112 In situ evaluation of multiple edible insects as feed for cattle

Abstract Livestock production is growing and intensifying in response to a growing population and associated food demands. Commercially reared insects have been positioned as a potential protein source for livestock due to their nutritional value and decreased environmental footprint as compared with conventional protein feeds. The American Association of Feed Officials (AAFCO) has issued a definition for black soldier fly larvae (BSFL) as feed for certain livestock but has not yet authorized feeding BSFL to ruminants. Further, AAFCO has not provided a feed definition for other edible insects [e.g., mealworm larvae (MWL)], likely due to a lack of research evaluating the value of insects as feed. The objective of this study was to evaluate edible insect species as feed for cattle by determining in situ characteristics of multiple commercially reared species. This research was approved by Texas State University IACUC (#8693). Samples (n = 14) included five insect species [i.e., black soldier fly larvae (BSFL)], mealworm larvae (MWL), house cricket, grasshopper, and banded cricket] that were commercially reared on different feed inputs and with various processing parameters and BSFL frass, which is insect excreta. There were 6 samples of BSFL, two of MWL, and three of house crickets. Three ruminally cannulated steers were used and provided ad libitum hay and water. A 6-d trial period was performed including a 3-d adaptation and 3-d experimental incubation period. Samples incubated in the rumen at 7 timepoints in reverse order (0, 4, 6, 12, 14, 48, and 72 h). After incubation, residues were analyzed for partial dry matter (PDM), dry matter (DM), and organic matter (OM). Dry matter and OM were separated into immediately soluble (IS), potentially soluble (PS), and not soluble (NS) fractions. For DM, the average NS fraction was 6.2% with a range from 3.0 to 10.4%. The sample with the greatest NS fraction was grasshopper. Across samples, the average PS fraction was 74.5% with a range from 69.3 to 79.1%. The sample with the smallest PS fraction was BSFL frass whereas the sample with the greatest was BSFL. Multiple samples had a DM degradability &amp;gt;85%. However, MWL and BSFL had fluctuating DM degradability across samples, likely due to variability among processing parameters. For OM fractionation, the average NS fraction was 5.7% with a range of 2.8 to 10.4%. Grasshopper had the greatest NS fraction. The average PS fraction was 74.9%; BSFL had the greatest PS fraction while frass had the least. Many samples had an OM degradability &amp;gt;85% and frass had the greatest degradability (90.0%). There was great variability in OM degradability across house cricket samples, likely related to rearing diet. These findings indicate that BSFL and MWL have potential value as feed for cattle but there would be challenges associated with feeding crickets.

85 Evaluation of a Saccharomyces cerevisiae fermentation product on performance, plasma metabolites, rumen parameters, and fecal pathogen shedding in feedlot steers

Abstract The objective of the experiment was to evaluate a commercial Saccharomyces cerevisiae fermentation product (SCFP; NaturSafe, Dimond V, Cedar Rapids, IA) on performance, plasma metabolites, rumen parameters, and fecal pathogen shedding in feedlot steers. Crossbred steers (n = 61; 271 ± 48.1 kg) were sourced from 3 different research units at Oklahoma State University and assigned to 1 of 3 experimental treatments in a randomized complete block design. Steers were group housed in pens equipped with an automated individual feed intake system. Treatments consisted of a negative control (CON), CON with tylosin phosphate (TYL; 9.9 mg · kg-1 of diet DM), or CON with SCFP (1.63 g · kg-1 of diet DM). Body weight and feed efficiency did not differ among treatments (P ≥ 0.12). However, steers fed SCFP tended to have greater ADG from d 35 to 56 (P = 0.10). In addition, steers fed SCFP exhibited increased DMI from d 56 to 112 (P = 0.03), a tendency for increased DMI from d 112 to final (P = 0.07), and increased DMI overall (P = 0.05). There was no treatment × time interaction for pH, pH change, or lactate concentrations in rumen fluid (P ≥ 0.11), but all were impacted by time (P &amp;lt; 0.01). A treatment × time interaction (P &amp;lt; 0.01) was detected for fecal pH and fecal pH change, with the pH being greater in TYL fed steers on d 56 and in CON fed steers on the final day. Steers that consumed CON had a reduced fecal pH (P &amp;lt; 0.01) and steers consuming SCFP tended to have a reduced fecal pH (P = 0.08) from d 35 to 56 compared with TYL fed steers, while both CON and SCFP fed steers experienced an increase in fecal pH from d 56 to 112 (P &amp;lt; 0.01). A time effect was detected (P ≤ 0.04) for plasma glucose, lactate, urea nitrogen, and non-esterified fatty acid concentrations among treatment groups. A treatment × time interaction was observed (P &amp;lt; 0.02) for stx2 genes of Shiga toxin producing Escherichia coli (STEC) in individual fecal samples where SCFP and TYL fed steers tended to exhibit an increased concentration compared with CON fed steers on d 14, while on d 190 CON and SCFP fed steers exhibited an increased concentration compared with TYL fed steers. Overall, STEC, E. coli O157:H7, and Salmonella concentrations were all impacted by time (P &amp;lt; 0.001). This experiment suggests that SCFP could be utilized as a potential alternative to TYL in feedlot cattle without adversely affecting cattle performance. However, SCFP did not impact pathogen shedding. In addition, CON fed steers performed similarly to both SCFP and TYL fed steers.