Yr Of Age Research Articles

Residual feed intake measured as replacement heifers is indicative of residual feed intake measured as mature cows

This study aimed to quantify the relationship between residual feed intake (RFI) measured in 500 heifers and subsequently as mid-gestation cows at the Roy Berg Kinsella Research Station (KIN; n=227) and Lacombe Research and Development Centre (LRDC; n=273). Heifers were initially tested for RFI adjusted for end of test rib fat (RFIfat) at 8-12 mo of age and then again as 3-yr old first-calf heifers at KIN and as 4-13 yr old cows at LRDC. Heifer RFIfat measured in drylot on a forage diet was associated (R2 >0.53; P < 0.001) with RFIfat measured again as older cows. Each 1 kg DM d-1 change in heifer RFIfat equaled 0.48±0.10 and 0.75±0.19 kg DM d-1 change in cow RFIfat for KIN and LRDC, respectively. Linear effects were also reported for RFIfat component traits, where DMI (P<0.001), ADG (P<0.060), mid-test metabolic weight (P<0.001) and end of test rib fat (P<0.001) measured as heifers were related when measured again as older cows. In addition, the linear effects of heifer RFIfat on cow RFIfat were constant across cow age groups from 4-10 yr of age. These results show that selection for RFI in heifers will result in cows that are also more feed efficient.

Parental non-compliance to childhood safety practices: A cross-sectional study.

Background & objectives To assess the pattern of non-compliance to childhood safety practices among parents of children between one and five yr of age and to determine the reasons behind the same. Methods A descriptive, cross-sectional study was conducted on 120 children between one and five yr of age through a questionnaire-based interview of the primary carer. Poor compliance was defined as compliance to <85 per cent of the recommended practices. Results Of the total 48 injuries, 32 were serious (66.6%). Falls and burns/scalds were the two common types of injuries. Nearly three-fourths (72.5%) of families showed overall poor compliance. Poorest compliance was observed towards four safety practices namely, helmet wearing, restricting number of pillion riders to two on a two-wheeler, seatbelt wearing in a car and avoiding food items with a high risk of choking in children <3 yr. Parental perception of 'unnecessary' and 'lack of knowledge' were the main reasons behind non-compliance. Interpretation & conclusions Low compliance among families occurred with respect to safety on motor vehicles and avoidance of choking hazards. Change of parental perception and improved awareness is necessary for the prevention of unintentional childhood injuries.

PSLBII-5 Impacts of residual feed intake measured as a heifer in drylot on mature cows and calves grazing native pasture

Abstract Selection for feed efficiency is crucial for improving economic and environmental sustainability in beef cattle production. Residual feed intake (RFIfat) is a commonly used measure of feed efficiency and is determined in a drylot setting by calculating the difference between observed and expected dry matter intake (DMI), where expected feed intake is adjusted for metabolic body weight (BW), average daily gain (ADG) and body fatness. Lower RFIfat cattle are more efficient animals as they eat less than predicted for the same growth, body size and body fatness. Limited studies have been conducted evaluating the role of RFIfat on the subsequent performance of cow-calf pairs on native range. Kinsella Composite cows and calves (n = 120) grazed native pasture from July 11 to Sept 12 (summer) and from Sept 13 to Nov 2 (fall) of 2023 were included in this study. All dams had previously been evaluated for RFIfat as a heifer (8 to 12 mo of age) using the GrowSafe Feed Intake System (Vytelle, Canada). Cow and calf ADG were subjected to an analysis of covariance using lm function from stats R core package (R Core Team, 2024), with cow age (2 to 8 yr of age) as the fixed effect and RFIfat as the covariate, analyzing separately by season. An unbalanced Tukey HDS post-hoc were applied for age and p-values &amp;lt; 0.05 were considered significant. Weight gain was assessed on cows with an initial BW on pasture of 598.4 ± 68.4 kg, and 2 to 8 yr of age, and on calves having an initial on pasture BW of 106 ± 21.5 kg, and 65 ± 14 d of age. Cow age affected (P &amp;lt; 0.01) cow ADG during summer, with the youngest dams (2 yr old) gaining more weight than older animals (7 yr old; Figure 1A). No effect of RFIfat was found on cow weight gain during summer grazing. However, during fall grazing, RFIfat affected (P &amp;lt; 0.01) cow ADG (Figure 1B). Low-RFIfat cows (efficient) had increased weight gain during fall grazing as compared with high-RFIfat cows (inefficient: Figure 1B). Calf ADG was not affected (P &amp;gt; 0.1) by cow age, cow RFIfat and cow ADG during summer and fall. We conclude that cows with low RFIfat exhibited superior body weight gain, during fall grazing on native range when forage nutrient quality and quantity become limiting.

PSIX-12 Influence of obesity on satiety hormones, serum metabolome, and fecal microbiome in adult dogs

Abstract The objective of this study was to investigate the difference between lean and obese dogs in terms of their satiety hormones, serum metabolome, and fecal microbiome. Mixed-breed lean (n = 30; 17 male and 13 female; 4.0 ± 2.5 yr of age; 24.6 ± 6.3% body fat) and obese (n = 30; 19 male and 11 female; 7.3 ± 2.1 yr of age; 46.9 ± 3.9% body fat) adult dogs were used in this study. Blood samples were collected to measure satiety hormones and serum metabolome, and fresh fecal samples were collected for microbiome analysis. It was hypothesized that obese dogs had altered metabolism and gut microbiome compared with lean dogs. Data were analyzed using MIXED procedure of SAS, using body type as the fixed effect and dog as the random effect. Results showed that obese dogs had greater (P &amp;lt; 0.05) serum leptin, insulin, and insulin-like growth factor-1 (IGF-1) concentrations, but reduced (P &amp;lt; 0.05) gastric inhibitory peptide (GIP) than lean dogs. Serum concentrations of all essential amino acids except for threonine in obese dogs were greater (P &amp;lt; 0.05) than in lean dogs. Obese dogs also had greater (P &amp;lt; 0.05) concentrations of serum N-Lactoyl amino acids and dipeptides except for prolylglycine than their lean counterparts. Additionally, concentrations of serum long-chain saturated and monounsaturated fatty acids were less (P &amp;lt; 0.05; only for myristate, pentadecanoate, and non-adecanoate) or similar in obese dogs compared with lean dogs. Serum oxidative stress makers, such as oxidized glutathione, cysteine-glutathione, and 4-hydroxynonenal, were greater (P &amp;lt; 0.05) in obese dogs than lean dogs. Furthermore, obese dogs had less (P &amp;lt; 0.05) fecal Firmicutes, but greater (P &amp;lt; 0.05) fecal Bacteroidetes and Fusobacteria, compared with lean dogs. There were no differences (P &amp;gt; 0.10) in fecal microbiome alpha diversity, such as Chao1 and Shannon index, between lean and obese dogs. In conclusion, obese dogs had differential body metabolism and gut microbiome compared with lean dogs.

PSIX-26 Effectiveness of mineral supplementation during range grazing on mineral status in ewes

Abstract Mineral supplementation in the intermountain west region of the US may be necessary for maintenance of healthy flocks since important trace minerals are deficient in this region. However, rough terrain can make mineral supplementation challenging. The objective of this study was to evaluate the trace mineral status of ewes on range. We hypothesized that ewes with access to a mineral supplement would have decreased risk of mineral deficiency. In this study, ewes (n = 59) grazed four summer pastures on Cedar Mountain near Cedar City, Utah. Ewes between the ages of 1 and 6 yr of age were stratified by initial body weight (BW) = 87 kg ± 13 kg and breed [black face (BLF; Suffolk) and white face breeds (WF; Targhee, Rambouillet, and their crosses)] into two treatment groups 1) trace mineral supplement ad libitum (TRT; n = 7 BLF and 23 WF) or 2) no mineral supplement (CON; n = 15 BLF and 14 WF). All ewes received a diet of mixed alfalfa and triticale hay without mineral supplementation 30 d before the trial began. A SmartFeed (C-lock Inc.) was used to track individual animal mineral intake. Plasma samples were collected via jugular venipuncture at d 0, 34, 77, and 116. A clinical veterinarian from Utah State University performed liver biopsies at d 0 and 116 on a subset of ewes (n = 10). After the grazing season, plasma and liver samples were sent to the Iowa State University Veterinary Diagnostic Laboratory for analysis of Cu, Mn, Se, and Zn. The mixed procedure of SAS was used to analyze plasma mineral content with day as a repeated measure and individual ID as a random variable. The Glimmix procedure of SAS was used to analyze liver mineral content. Plasma Cu and Se increased (P ≤ 0.05) by day in all ewes throughout the grazing season. No differences related to treatment or breed (P &amp;gt; 0.10) were observed for plasma Cu or Se concentrations. Plasma Mn and Zn decreased (P &amp;lt; 0.0001) by 1.5 ppb and 0.4 ppm, respectively, between d 0 and 116 with no treatment effect (P &amp;gt; 0.10). BLF ewes had 0.3 ppm (P = 0.01) greater plasma Mn concentrations than WF ewes, with no difference (P = 0.6) observed due to treatment. Hepatic Cu and Se increased (P ≤ 0.05) by 114 ppm and 1 ppm, respectively, between d 0 and 116. Hepatic Mn concentrations did not differ (P &amp;gt; 0.10) by day or treatment. Hepatic Zn concentrations tended to increase by day (P = 0.07), 23 ppm between d 0 and 116. CON ewes had 28 ppm greater (P = 0.04) hepatic Zn concentrations than TRT ewes. Additional research is warranted to understand why CON had greater hepatic Zn concentrations than TRT, which may indicate that diverse rangeland forages may provide sufficient concentrations for sheep production in summer months.

PSI-8 Inflammatory cytokine concentrations and gene expression in mature and aging sedentary horses

Abstract Chronic inflammation associated with aging, termed “inflamm-aging” may negatively impact overall animal health. However, the mechanisms of inflamm-aging and, therefore, effective interventions, remain unknown. Nuclear factor erythroid 2-related factor 2 (Nrf2; NFE2L2) is a transcription factor that controls antioxidant gene expression and could be a target for promoting anti-inflammatory pathways. To test the hypothesis that supplementation of nonenzymatic derived antioxidants (Protandim Nrf2 Synergizer, LifeVantage Corporation) would activate Nrf2 and mitigate inflammation, 40 mature, sedentary horses [32 mares, 8 geldings; 15.7 ± 4.9 yr of age, body weight (BW) = 519 ± 46 kg] were stratified by age, sex, and BW and randomly assigned to one of four dietary treatment groups for 56 d: 1) 0 mg (CON); 2) 675 mg (Pro1); 3) 2,025 mg (Pro3); or 4) 4,050 mg (Pro6) Protandim Nrf2 Synergizer per day (n = 10 per group). Blood samples were collected at d 0 (September, 27°C, 61.6% humidity), d 28 (October, 21.6°C, 55.8% humidity), and d 56 (November, 15.1°C, 73.8% humidity) of supplementation prior to the morning feeding. Plasma cytokine concentrations of tumor necrosis factor (TNF)-α, interleukin (IL)-4, IL-6, IL-8, and IL-10 were quantified using custom Meso Scale Discovery U-Plex kits and whole blood gene expression of IL-1β, NFE2L2, and heme oxygenase 1 (HMOX1) were determined using qRT-PCR. Data were analyzed using PROC MIXED in SAS v9.4 with sex, time, treatment, age (under or over 15 yr), and time × treatment as fixed effects and time as a repeated effect with horse(treatment) as the subject. Day 0 was included as a covariate when treatment groups differed at d 0. Relationships between age and cytokine concentrations or mRNA expression were determined using PROC CORR. Plasma IL-4 (r = 0.4054) concentrations as well as whole blood HMOX1 (r = 0.3437) and NFE2L2 (r = 0.3382) expression on d 0 were positively correlated with age (P ≤ 0.04). Regardless of treatment or age, IL-1β and NFE2L2 expression and IL-4 and IL-8 concentrations decreased from d 0 to 28 (P ≤ 0.03) and remained depressed at d 56 (P ≤ 0.02) while IL-10 was not different from d 0 to 28 but decreased from d 0 to 56 (P = 0.02). TNFα concentrations were not different between treatments or over time. These data corroborate increased inflammatory markers with age and suggest a change in inflammatory status over time potentially due to seasonal environmental factors.

PSII-14 Climate and conception: Investigating the resilience of equine embryo survival to ambient temperatures in southeast Texas

Abstract Amidst the unique challenges posed by the humid and hot climate of southeast Texas, this study aimed to assess the establishment of pregnancy from transferred equine embryos, hypothesizing that an increase in ambient temperature would lead to a decrease in pregnancy establishment. To achieve this, we utilized 17 embryo donors and 46 recipient mares (3 to 9 yr of age), all anatomically and clinically normal with no history of reproductive problems. Breeding records for 49 transferred d 8, grade-1 embryos from a single private horse farm in southeast Texas, along with the reported high and low ambient temperatures on the day of transfer, were analyzed using logistic regression via PROC GLIMMIX in SAS v9.4 with fixed effects for the reported high and low ambient temperatures on the day of transfer, with a random statement for donor and sire. The pregnancy rate for all embryo transfers was 79%. Surprisingly, our results revealed that neither the reported high ambient temperatures (P = 0.16) nor reported low ambient temperatures (P = 0.19) significantly influenced the likelihood of pregnancy establishment observed at d 14 post-ovulation of transferred equine embryos. Furthermore, no statistically significant influence (P &amp;gt; 0.05) on pregnancy establishment was observed when embryo transfers were conducted outside of the thermal neutral zone (5°C to 20°C). Within the context of our study, these results suggest that environmental temperatures in southeast Texas do not significantly impact equine pregnancy outcomes.

PSX-4 Exploring the impact of age and body condition score on the genetic analysis of mature cow weight in American Angus cattle

Abstract Selecting sires with optimal genetic merit for mature weight (MWT) is crucial for profitability of beef producers, ensuring cost-effective production and increased economic returns per animal. The main objective of this study was to determine how different statistical approaches [e.g., including the fixed effects (FE) of age and body condition score (BCS) in the statistical model and/or pre-adjusting the weights for these effects] affect variance components estimation and genetic parameters for MWT, and their impact in the posterior selection decisions. The dataset provided by the American Angus Association (AAA) comprised 80,296 MWT records from 37,934 cows aged 2 to 15 yr. Contemporary groups (CG) were defined by concatenating herd, year, and season of measurement. Model 1 analyzed unadjusted MWT with CG and BCS as categorical FE and age as a covariable (quadratic). Model 2 was model 1 without BCS, model 3 was model 1 without age, and model 4 considered CG as the only FE. In model 5, MWT was pre-adjusted for 6 yr of age and BCS of 6, and CG was the only FE included in the statistical model. Additive genetic and permanent environment (pe) random effects were included in all statistical models except model 5, which did not include pe (only one adjusted record per animal). Variance components were calculated using REML implemented in the BLUPf90+ family of programs. Sires with at least 10 offspring (n = 1,483) were ranked according to their breeding values (EBVs) predicted for MWT, and all and the top 10% sires were used to estimate the rank correlation across models. The heritability (± SE) estimated for MWT was 0.43 (± 0.011), 0.42 (± 0.011), 0.70 (± 0.008), 0.72 (± 0.082), and 0.37 (± 0.013) for models 1, 2, 3, 4, and 5, respectively. Repeatability values were 0.64, 0.67, 0.72, and 0.76 for models 1, 2, 3, and 4, respectively. The EBV ranks were highly correlated between models 1 and 2 (Top 10%: 0.96; All: 0.99), and models 3 and 4 (Top 10%: 0.99; All: 0.99). Inflated heritabilities in models 3 and 4 suggest that the effect of age is confounded with the additive genetic effect, which will not translate to greater genetic progress. Therefore, disregarding age in the genetic evaluation of MWT is not recommended. Similarities between models 1 and 2 suggest that BCS has a relatively small impact on MWT, probably related to the relatively low genetic correlation between these traits. Models 1 and 5 cannot be directly compared, as they use slightly different response variables (body weight vs. pre-adjusted weight) and may lead to slightly different selection decisions (correlation between Top 10%: 0.85; All: 0.95). Further investigations in this field are warranted.

PSIX-11 Effects of black soldier fly larvae on the serum chemistry, hematology, fecal characteristics, and oral health measures of healthy adult cats

Abstract Black soldier fly larvae (BSFL) serve as an alternative protein source for pet food products. Even though BSFL are one of many insect species being added to dog foods and treats, knowledge of its effects in cats remains limited. Further investigations are imperative to delineate the effects of BSFL-based ingredients in cats. Therefore, the objective of this study was to determine the effects of BSFL on serum chemistry, hematology, fecal characteristics, and oral health measures of adult cats. All procedures were approved by the University of Illinois IACUC prior to experimentation. Adult cats [n = 25; 17 females, 8 males; 6.28 ± 0.27 yr of age; 4.50 ± 0.18 kg body weight (BW)] were used in a completely randomized design. The study was composed of a 21-d baseline phase and a 70-d experimental phase. During the baseline phase, all cats were fed a control diet based on chicken meal (35% of diet). After baseline, cats were randomly assigned to 1 of 2 experimental diets: control diet (n = 12) or BSFL-containing diet (20% whole BSFL meal and 24% chicken meal; n = 13). At baseline, teeth were cleaned by a veterinary dentist. Breath samples were analyzed for volatile sulfur compounds (VSC), salivary pH was measured, and blood samples were collected for serum chemistry and hematology at baseline and after 35 d and 70 d on treatment. At baseline and after 70 d on treatment, fecal samples were scored and collected for pH, dry matter, and metabolite measurement. Gingivitis, plaque, and calculus scores were performed by a veterinary dentist after 70 d on treatment. All data were analyzed using the Mixed Models procedure of SAS. Diet, time, and diet*time interaction effects were tested, with P &amp;lt; 0.05 being considered significant. Over time, VSC increased (P &amp;lt; 0.0001) in all cats, but was unaffected by diet. Diet*time interactions were observed for fecal pH, fecal scores, and blood cholesterol and triglyceride concentrations. Blood cholesterol concentrations increased (P &amp;lt; 0.05) over time in cats fed the control diet, but remained stable in cats fed the BSFL diet. The opposite effect was observed with blood triglycerides. Triglyceride concentrations increased (P &amp;lt; 0.05) in cats fed the BSFL diet over time, but were stable in cats fed the control diet. Cats consuming BSFL had reduced (P &amp;lt; 0.05) fecal pH, dry matter content, and protein catabolite concentrations, but increased (P &amp;lt; 0.05) fecal short-chain fatty acid concentrations and fecal scores. Overall, 20% BSFL dietary inclusion had comparable effects as chicken meal, suggesting that it will serve as a suitable replacement in cat foods.

PSX-16 The effect of short-term heat stress on physiological, hematological, and immunological parameters of Florida Cracker Sheep

Abstract Florida Cracker sheep are a heritage sheep breed that was developed under natural selection in Florida, US. The objective of this study was to evaluate the effect of short-term heat stress on rectal temperature, respiration rate, hematological parameters, and IgA concentrations of Florida Cracker ewes (2 yr of age). A total of fourteen ewes were allocated to heat stress (HT, n = 7) or cooling (CTL, n = 7) conditions for 6 wk during the summer season. Treatment groups were grouped in covered concrete floor pens with similar dimensions and characteristics and had access to shelter, feed, and freshwater ad libitum. The HT pen was exposed to regular ambient temperatures, and for the cooling pen, an evaporative cooling fan was used. Data for ambient temperature and relative humidity of HT and CTL pens were recorded every week to estimate the temperature humidity index (THI). Blood samples were collected from each experimental ewe 1 wk before the start of the experiment (baseline) and at wk 1, wk 2, wk 3, wk 4, wk 5, and wk 6 post-treatment. Blood samples were analyzed using a hematology analyzer (Vetscan HM5, Zoetis). Plasma was extracted from the blood and was used to evaluate IgA concentrations with a commercial kit. For the statistical analysis of the physiological, hematological, and immunological parameters, a mixed model with repeated measures was used. Fixed effects included treatment (HT or CTL), wk (1 to 6), and the treatment by week interaction. Animal was fitted as a random effect and the baseline data was used as a covariate. The THI for the HT and CTL groups ranged from 81.3 to 89.5 and from 73.5 to 75.6, respectively. The HT group presented a significant (P &amp;lt; 0.05) increase in respiratory rate when compared with the CTL group. No significant changes were observed for rectal temperature and IgA concentrations in the experimental groups. However, for wk 3, a significant (P &amp;lt; 0.05) increase of neutrophils and a decrease in lymphocyte % was observed for the HT group. In conclusion, short-term heat stress increased respiratory rate and neutrophil % and decreased the lymphocyte % in Florida Cracker ewes. It is possible that heat stress could have a detrimental impact on immune mechanisms in Florida Cracker ewes. Further studies are required to investigate the effects of long-term heat stress.

PSIV-15 Effect of transient fetal bovine viral diarrhea virus infection on postnatal growth, estimated dry matter digestibility, glucose concentrations, and carcass characteristics

Abstract Fetal infection of bovine viral diarrhea virus (BVDV) before d 125 to 150 of gestation results in the birth of immunotolerant, persistently infected (PI) calves. Infection of BVDV during late gestation results in transient fetal infections (TI). Unvaccinated, yearling Hereford heifers (n = 25), seronegative for antibodies to BVDV1 and BVDV2, were bred by artificial insemination with X chromosome-bearing sperm from an Angus sire to examine the impact of TI on postnatal growth, estimated dry matter digestibility, blood glucose concentrations, and carcass characteristics. On d 175 of pregnancy, heifers were intranasally inoculated with either DMEM + 2% horse serum (sham control) to generate control calves or 4.0 log TCID50 noncytopathic type2 BVDV to generate TI calves. All sham-inoculated control dams remained seronegative, and all BVDV-inoculated dams seroconverted by d 14 post-inoculation. Sham-inoculated control dams (n = 12) and BVDV-inoculated dams (n = 12) gave birth to live calves. All control offspring were seronegative, and all TI offspring were seropositive for antibodies to type 2 BVDV at birth. All offspring were raised on pasture until weaning. At weaning, all calves were transported to our feedlot research facility, housed in one group feedlot pen, and transitioned to a high-energy concentrate-based diet until reaching an approximate BW of 600 kg. Upon arrival at the feedlot, all animals received a standard heifer growth implant, a modified live viral vaccine containing IBR-BRSV-PI3 and were dewormed. Heifer BW and jugular blood samples were collected every 28 d. On d 84 of the feeding period, titanium dioxide was added to the diet of 12, age-paired, individually fed, heifers (3 control and 3 TI heifers; approximately 1 yr of age) for 28 d and used to estimate dry matter digestibility. After approximately 280 d on feed heifers were transported to a USDA-inspected abattoir and harvested. The TI heifers had lighter birth weights (P &amp;lt; 0.03) and final BW (P &amp;lt; 0.04) when compared with control heifers. Average daily gain was greater (P &amp;lt; 0.01) in control compared with TI heifers. Blood glucose concentrations were similar between control and TI heifers at all sampling time points. Dry matter intake of individually fed heifers was similar across treatments. TI heifers had a 2.2% lesser (P &amp;lt; 0.05) dry matter digestibility and lighter (P &amp;lt; 0.01) hot carcass weights compared with controls. These data suggest that TI fetal BVDV infection negatively impacts growth throughout the feeding period, possibly by impacting gastrointestinal tract function. This research was supported by USDA-NIFA Grant # 2019-67015-29866.

182 Converting spring-born heifers into a summer-calving herd increases subsequent cow longevity and productivity

Abstract Developing replacement heifers is one of the most expensive and complex management decisions for a cow-calf producer, which also has long-term implications for profitability. The objective of this study was to determine the impact of converting spring-born heifers into a summer-calving herd on growth, reproductive performance, longevity, and productivity compared with early or late-born May heifers. Over a 3 yr period, Red Angus/Simmental crossbred heifers (n = 273) were utilized to determine the impact of converting March-born heifers (Convert; n = 90) to a May-calving herd compared with May-born heifers on reproductive performance, body weight (BW), and calf performance from a yearling to 5 yr of age. May-born heifers were retrospectively grouped into 2 different groups: heifers born in the first 21 d of calving as a heifer calf (Early; n = 123) or heifers born after the 21 d of calving as a heifer calf (Late; n = 60). Heifers were exposed to bulls for a 45-d breeding season with a bull-to-heifer ratio of 1:20. Heifers were synchronized with a single injection of prostaglandin F2α (5-mL i.m.; Lutalyse, Zoetis, Parsippany, NJ) 5 d after bulls were introduced in the pasture for breeding. Data were analyzed as a randomized design using the MIXED procedure (SAS Inst. Inc., Cary, NC, USA). All binomial data were analyzed using PROC GLIMMIX. Heifer served as the experimental unit with treatment and year developed set as fixed effects. Heifer BW at December, May, July, and pregnancy check (Oct) were greater (P &amp;lt; 0.01) for Convert heifers with no difference between Early and Late born heifers. Heifer BCS at pregnancy check was not different (P = 0.13) among heifer treatment groups. However, pregnancy rate tended (P = 0.08) to increase for Convert heifers with no difference between Early and Late born May heifers. After 5 yr of age, retention rate was increased (P = 0.04) in Convert cows compared with Early and Late May-born cows with no difference (P = 0.84) between the two May-born heifer groups. Total kilograms of calf weaned was greater (P = 0.04) in Convert cows than their counterparts with no differences (P = 0.94) between Early and Late May-born cows. This study implies that selecting replacement heifers from an earlier calving season for replacements in a later calving season increases the longevity and long-term productivity of the cowherd than selecting heifers within the same calving season. This may be even more important in resource-poor breeding environments that create reproductive challenges for heifers and rebreeding young cows.

52 Differences in body composition measurements for developing Angus heifers

Abstract The profitability of beef cow-calf operations relies on the reproductive ability of females to calve at 2 yr of age and provide a calf each subsequent year for her lifetime. The management of replacement heifers could affect her ability to conceive early, calve, and rebreed. Common management practices use heifer body weight (BW) (and body condition score (BCS) as indicators of puberty onset but do not indicate body composition and fat deposition. The objective of this study was to use ultrasound measurements of carcass traits to compare the effect of different diet management practices on muscle development and fat deposition of post-weaning heifers. The heifers placed on a higher energy diet are expected to have greater mean carcass trait measurements than the lower energy diet heifers. A total of 124 purebred Angus heifers from the Iowa State University McNay Memorial Research and Demonstration Farm were used for this study. Two diets were administered in this study. One group of heifers (G1; n = 61) was developed on a low-energy roughage diet to reach a target BW of 55% of mature BW at the time of breeding. The second group (G2; n = 63) was developed on a grain diet to reach the target BW of 65% mature BW at breeding. Body weight and ultrasound measurements for backfat (BFAT), ribeye area (REA), and intramuscular fat (IMF) were collected over three time points (0-d, 55-d, and 123-d) during the study to quantify the development of body composition characteristics. The initial measurements were collected 1 wk post-weaning. Significant mean differences between the two groups were observed for BW, BFAT, and REA at 55-d (P = 0.027, P = 0.008, and P &amp;lt; 0.0001, respectively), and 123-d (P &amp;lt; 0.001). The mean differences for BW, BFAT, and REA at 123-d between G1 and G2 were 30.98 kg, 0.10 cm, and 7.81 cm2, respectively No significant difference was found between the groups for IMF measurements at 55-d (P = 0.927) or 123-d (P = 0.169). This suggests IMF is not significantly influenced by diet during the early, post-weaning heifer developmental stage. Although further research is needed, the results from this study suggest the development of weight, BFAT, and REA in early post-weaning beef heifers is influenced by the energy concentration of the diet.

HEMATOLOGY AND BIOCHEMICAL REFERENCE INTERVALS FOR FREE-RANGING PRONGHORN (ANTILOCAPRA AMERICANA) IN WEST TEXAS.

Pronghorn (Antilocapra americana) are considered a keystone species of North American grasslands and an important economic source for many landowners in Texas. Pronghorn restoration projects routinely capture and translocate individuals from surplus populations to restoration areas. The objective of this study was to generate normal hematological and biochemical reference intervals (RI) for free-ranging pronghorn populations in Texas as a health monitoring tool for pronghorn restoration efforts. Blood samples were collected by jugular venipuncture and divided among an EDTA tube, serum separator tube, and a single blood smear on site. Complete blood counts and biochemical profiles were completed at the Texas Veterinary Medical Diagnostic Laboratory. In total, 417 individuals (41 males, 376 females) were included in the analysis. RI were determined by robust methods (R Studio) and mixed models' analysis of variance (SPSS 28) to examine differences in blood parameters due to fever, sex, age (adult versus yearling [<1 yr of age]), cell abnormalities, and pathogen exposure reported by the testing laboratory. Sex, age, and pathogen exposure affected mean blood values, but did not warrant development of separate RI by class. Bluetongue virus was identified in 46.8% (195/417) of pronghorns and epizootic hemorrhagic disease in 89.4% (194/217) of pronghorns; 84.8% (184/217) of the pronghorns tested positive for both diseases. This information provides baseline hematology and biochemical parameters to assess the health of free-ranging pronghorn and guide wildlife managers in decision-making for future translocations and restoration objectives.

204 Detecting subclinical mastitis in meat-breed ewes using infrared thermography

Abstract Mastitis, the inflammation of the mammary gland most commonly due to bacterial infection, is an important welfare concern in meat-breed sheep. The objective of our study was to evaluate udder surface temperature obtained from infrared thermography as a diagnostic tool for subclinical mastitis. We predicted that udder halves with subclinical mastitis would have greater surface temperatures than healthy udder halves. We enrolled 39 meat-breed ewes (10 Hampshire, 24 Polypay, 5 Targhee; 2 to 9 yr of age) at the University of Wisconsin-Madison sheep unit. All procedures were approved by the UW-Madison Institutional Animal Care and Use Committee. Milk samples from each udder half were collected in duplicate weekly beginning 2 to 4 d postpartum until 8 wk postpartum. Immediately before milk sampling, the udder was photographed from the rear using a thermal camera. A sample was considered a true infection if at least 100 CFU/mL of a bacterial species were isolated. From each photo, we obtained values for minimum, maximum, and mean skin surface temperature for the right and left udders. Three linear mixed models were fit using minimum, maximum, and mean temperatures as the response variables. Fixed effects were infection status (infected or not), weeks postpartum (wk 1-8), and ambient temperature, with a random effect of udder half nested within animal ID. Contrary to our predictions, infection status did not predict udder skin surface temperature (P &amp;gt; 0.12). Healthy udder halves had a mean temperature of 35.5 ± 0.1°C (mean ± SE), minimum temperature of 29.9 ± 0.3°C, and maximum temperature of 37.8 ± 0.1°C. Infected udder halves had a mean temperature of 35.4 ± 0.1°C, minimum temperature of 30.5 ± 0.3°C, and maximum temperature of 37.7 ± 0.1°C. Our results contradict findings in dairy cows, and suggest more research is needed to evaluate the relationship between udder surface temperature and subclinical mastitis in sheep.

Neurodevelopmental outcome in preterm infants with intraventricular hemorrhages: the potential of quantitative brainstem MRI.

This retrospective study aimed to identify quantitative magnetic resonance imaging markers in the brainstem of preterm neonates with intraventricular hemorrhages. It delves into the intricate associations between quantitative brainstem magnetic resonance imaging metrics and neurodevelopmental outcomes in preterm infants with intraventricular hemorrhage, aiming to elucidate potential relationships and their clinical implications. Neuroimaging was performed on preterm neonates with intraventricular hemorrhage using a multi-dynamic multi-echo sequence to determine T1 relaxation time, T2 relaxation time, and proton density in specific brainstem regions. Neonatal outcome scores were collected using the Bayley Scales of Infant and Toddler Development. Statistical analysis aimed to explore potential correlations between magnetic resonance imaging metrics and neurodevelopmental outcomes. Sixty preterm neonates (mean gestational age at birth 26.26 ± 2.69wk; n = 24 [40%] females) were included. The T2 relaxation time of the midbrain exhibited significant positive correlations with cognitive (r = 0.538, P < 0.0001, Pearson's correlation), motor (r = 0.530, P < 0.0001), and language (r = 0.449, P = 0.0008) composite scores at 1 yr of age. Quantitative magnetic resonance imaging can provide valuable insights into neurodevelopmental outcomes after intraventricular hemorrhage, potentially aiding in identifying at-risk neonates. Multi-dynamic multi-echo sequence sequences hold promise as an adjunct to conventional sequences, enhancing the sensitivity of neonatal magnetic resonance neuroimaging and supporting clinical decision-making for these vulnerable patients.

136 Evaluation of internal parasite burden in grazing beef cattle in North Carolina over a production lifecycle

Abstract Gastrointestinal nematode (GIN) parasite infections can be detrimental to not only cattle health and immunity, but also result in economic loss and poor performance. Cattle grazing in the southeast are challenged even further by the favorable environmental conditions for parasite development, especially those animals who have yet to develop an immunity to combat parasitism. To diminish potential economic and performance-based losses, many beef producers treat animals for GIN parasites with anthelmintics on a regular basis without proper diagnosis. Anthelmintic resistance(AR) develops when deworming products are overused and misused. To minimize the development of AR, selective deworming and sustainable management practices should be implemented. However, the severity of parasite burden over the production cycle needs to be better understood in beef cattle herds before recommendations can be made. Thus, the objective was to investigate the rates of GIN parasite infections through fecal egg counts (FEC) and the impact on body weight (BW) and body condition score (BCS). Angus-based cattle (6 mo-13 yr, n = 1,154) on a were utilized from five different research and educational herds across North Carolina. Cattle were categorized based on their age at the start of the project as either calves (n = 446), yearling heifers (n = 205), 2 year old (n = 260), 3-5 year old (n = 501), or 6+ year old (n = 206). Starting in September, FEC, BW, and BCS were collected and analyzed every 90 d at critical production timepoints (calving, breeding, weaning, and 90d post-weaning) to monitor the severity of GIN parasite challenge. Cattle on study were not treated with anthelmintics regardless of parasite load, with the exception of calves at four of the locations at the time of weaning. All data were analyzed using Proc MIXED in SAS with repeated measures. Statistical significance was declared at P ≤ 0.05 and a trend at 0.10 &amp;gt; P &amp;gt; 0.05. Age of cattle had an impact on FEC overall (P &amp;lt; 0.05), however, there was no difference between FEC of mature cattle over 3 yr (4.29 ± 4.9 eggs/gm). Calves had the greatest FEC (120.59 ± 4.2 eggs/gm) while cattle 6+ yr had the least (3.68 ± 4.5 eggs/gm). Cattle age at each location affected BCS and BW (P &amp;lt; 0.05). Between age groups across locations, time had an impact on FEC, BW, and BCS (P &amp;lt; 0.05). There was also a tendency (P = 0.6) for location to impact FEC. Calf sex did not affect (P &amp;gt; 0.05) FEC. Further FEC analysis of cattle under 2 yrof age is required to better understand when a natural immune response to GIN parasite infections develops.

Molecular Characterization and Phylogenetic Relationship of VP6 Gene of Rotavirus among Canine, Porcine and Human Infants

Background: Rotaviruses have been widely reported and have a worldwide prevalence to be associated with diarrhea in humans but fewer studies abound on other mammalian species. Group A Rotavirus (RVA) are majorly responsible for causing acute gastroenteritis (AGE) in humans and animals. Methods: In the present study 150 diarrheic fecal samples from, piglets, pups and human infants (0-5 yr of age) were screened for the presence of rotaviruses by lateral flow assay, VP6-based RT-PCR assay and phylogenetic analysis. Result: A total of 13/150 (8.6%) fecal samples were found positive by lateral flow assay. Out of 50 diarrheic fecal samples each of human infants 4 (8.0%), pups, 03 (6.0%), piglet samples 6 (12.00%) showed the presence of rotavirus. All 13 positive fecal samples from piglets, pups and human infants were further screened for the detection of group A Rotavirus by VP6 gene-based RT-PCR assay. Of the samples tested, 13 (100.00%) samples were found positive for Rotavirus. The sequences of VP6 gene amplified from piglet, pups and human infants were subjected to phylogenetic analysis. The phylogenetic analysis showed that there is not much sequence variation between rotavirus from human infant and piglet. It showed more identity with Homo sapiens and Bos taurus which indicated the possibility of zoonotic transmission.

How Age, Sex and Transfusion Affects the Incidence of Endocrine and Bone Density Disorders in Major Thalassemic Patients.

Beta-thalassemia major patients frequently have endocrinopathies. We tried to determine relation between demographic and transfusion factor and endocrinopathies. Major beta-thalassemia patients (n=114 cases), 3-38 yr of age, entered this study. Female to male ratio was 51/63. Children (less than 20 yr) formed 57% of participants. Information about bone mineral density (BMD) and hormonal and biochemistry blood evaluation including fasting blood sugar (FBS), ferritin, triiodothyronine (T3), thyroxine (T4) and thyroid-stimulating hormone (TSH), luteinizing hormone (LH) and follicle-stimulating hormone (FSH), testosterone (males), and estradiol (females) entered data sheet. Sex and ferritin level showed no significant correlation with above disorders. Age significantly correlated to short stature, diabetes, low BMD at femur and neck (P, 0.031, 0.008, 0.009 and <0.001, respectively) . The risk of short stature had increased in 12 yr and older patients 7.71 times than younger patients (P= 0.008). The risk of diabetes had increased in 35 yr and older patients 26.25 times than younger patients (P= 0.03). The risk of Z-score ≤ -2 in femoral region has increased in 19 yr and older patients 5.84 times than younger patients (P= 0.002). The risk of Z-score ≤ -2 in spinal region has increased in 14 yr and older patients 17 times than younger patients (P= 0.007). The main factor related with endocrinopathies was age. The correlation between age and short stature, diabetes and low BMD was positive. Therefore, we recommend early monitoring of thalassemia patients (in their late childhood and early teenage) for these complications.

Comparing bluegill growth among newly constructed, renovated, and established flood-control reservoirs in southeastern Nebraska

Perrion MA, Lebsock JR, Werner JP, Blank AJ, Miller BT. 2024. Comparing bluegill growth among newly constructed, renovated, and established flood-control reservoirs in southeastern Nebraska. Lake Reserv Manage. 40:57–65. Multiple reservoirs have been constructed in the last 10 yr in southeastern Nebraska for flood control and recreational purposes. In addition, other existing reservoirs have undergone major renovations in the same time period to remove sediment and aquatic invasive species. This situation created the opportunity to compare bluegill (Lepomis machrochirus) growth between newly constructed, renovated, and established reservoirs. This study analyzed bluegill growth data from 8 different flood-control reservoirs in southeastern Nebraska in 2021 and 2022. The study objectives were to (1) determine aging precision of scales and otoliths in bluegill and (2) evaluate bluegill growth among new, renovated, and established flood-control reservoirs. For all bluegill collected during the study, exact percent agreement for otolith ages between 2 readers was 89.6%, and percent agreement was 99.1% within 1 yr of age. For scales, exact percent agreement was 48.0% and 84.3% within 1 yr. Mean lengths at age for all reservoir types were similar for age-2 bluegill, whereas age-3 bluegill had longer mean lengths in renovated reservoirs than in either new or established reservoirs. Mean lengths of age-4 bluegill from new and renovated reservoirs were similar, but greater than mean lengths of age-4 bluegill in established reservoirs. Results of this study further demonstrate the greater precision of whole view otolith aging for bluegills compared to scale estimates and will benefit future managers making management decisions for bluegills. Managers can also use information ascertained from bluegill growth metrics to further manage bluegill populations based on reservoir age and management objectives.