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Length of the menstrual cycle was positively associated with antral follicle number in women. If this pattern is consistent in cattle, a value-added benefit to using automated activity monitors to determine estrous status could be the ability to predict antral follicle count (AFC). We, therefore, hypothesized that as inter-estrous interval increased ultrasonographic AFC would be greater in crossbred beef heifers. Over 3 yr, crossbred beef heifers (n  = 1,394) were fitted with automated activity monitors for 81 d. From days 42 to 46, heifers were submitted for ultrasonographic examination to determine AFC. From days 60 to 81, heifers were visually observed twice daily for 45 min for signs of behavioral estrus. Heifers that had a behavioral estrus that coincided with a sensor-based estrus and had a previous sensor-based estrus between 15 and 26 d earlier were used for the analysis (n  = 850). A combination of regression analyses and correlation analyses were applied to understand the association between data collected by sensors and follicle number determined by ultrasonographic examination. Antral follicle count was analyzed using the GLM procedure of SAS with estrous cycle length (15 to 26 d) as a fixed effect. Estrus was more likely to initiate in the early morning hours and peak activity was greater (P  < 0.0001) when estrus initiated between 0200 and 0800 hours then when estrus initiated at other times of the day. Antral follicle count did not differ due to length of the estrous cycle (P  = 0.87). Thus, length of the estrous cycle obtained from three-axis accelerometers cannot be used to predict follicle number in crossbred beef heifers; however, machine learning approaches that combine multiple features could be used to integrate parameters of activity with other relevant environmental and management data to quantify AFC and improve reproductive management in beef cows. [ABSTRACT FROM AUTHOR]

Early identification of animals in need of management intervention is critical to maximize animal health and welfare and minimize issues with productivity. Feeding behavior, captured by automated feeding systems, can be used to monitor the health and welfare status of individual pigs. Here, we present a framework for monitoring feeding behavior of grow-finish pigs in real time, using a low-frequency radio frequency identification (RFID) system. Using historical data, an autoregressive linear model for predicting daily time at the feeder was developed and utilized to detect anomalous decreases in feeding behavior associated with health status of the pig. A total of 2,826 pigs were individually monitored with our warning system over the entire grow-finish period, and health warnings were compared to caretaker diagnoses. The system detected 55.7% of the caretaker diagnoses, and on average these events were detected 2.8 d earlier than diagnosis by the caretaker. High numbers of potentially spurious health warnings, generated by the system, can be partly explained by the lack of a reliable and repeatable gold standard reference data set. Results from this work provide a solid basis for monitoring individual animals, but further improvements to the system are necessary for practical implementation. [ABSTRACT FROM AUTHOR]

The objective was to determine the genetic factors influencing mobility traits recorded from 5 mo-old gilts. Mobility was measured using a pressuresensing mat (GAIT4) and 7 d of video recorded activity (NUtrack). Gilts (n = 3,659) were evaluated for the study, but only 2,172 gilts had data for both systems. GAIT4 system creates a series of measurements for each foot related to pressure, duration and step length of each foot generating a lameness score for each foot. Traits studied summarized values for all 4 feet: average stride length, average stance time, standard deviation of stance time, lameness score and total scaled pressure. NUtrack measurements were rotations, velocity, and distance walked as well as the time spent eating, sitting, standing, lying sternal and lying lateral. All NUtrack traits were standardized to a mean of zero and standard deviation of 1.0 based on each pen-day subgroup. Mixed model analyses were conducted in R fitting animal as a random effect and fixed effects of breed of sire and contemporary group, with day included for NUtrack data. ssGBLUP analyses were conducted in WOMBAT using animal effects from R models as phenotypes. Three generations of pedigree were included and genotypic data from the NeoGen Porcine 50K beadchip on 3,186 animals representing 60% of gilts with NUtrack data, 67% of gilts with GAIT4 data and most parents (>99%). Single trait analyses were conducted for all traits, gEBVs estimated and then SNP effects estimated by back-solving equations. Significance values were determined by 5,000 permutations and a Bonferroni adjustment factor applied. Estimates of heritability ranged from 0.08 to 0.41 and traits from the NUtrack system tended to have greater heritability than GAIT4 traits. There were 343 significant SNP effects in 39 unique chromosomal regions. There were 133 significant SNP associations located on chromosome 14 between 45-47 Mb associated with rotations, distance and times standing and lying. Pathway analysis identified proteoglycan and apelin pathways to be over-represented based on associations with SNP located at 2:45, 2:51, 13:79 and 14:40 (SSC:Mb). Proteoglycans are a subunit of cartilage and apelins affect blood flow and angiogenesis which make them candidates for the development of osteochondrosis, a leading cause of lameness in pigs. These results will facilitate selection of more robust animals capable of withstanding commercial production environments and group sow housing. USDA is an equal opportunity employer. [ABSTRACT FROM AUTHOR]

New findings in developmental programming show an increased importance of methyl donor availability; however, effects of changing methyl donor concentration on the fetal transcriptome have yet to be identified. Differential gene expression (DEG) was used to determine the impact of maternal supplementation of methionine (MET), an obligate methyl donor, and guanidinoacetic acid (GAA), a methyl donor consumer, during the periconceptual period on bovine fetal development. MARC II heifers [n = 80; initial body weight (BW) = 346 ± 8.28 kg] receiving the same mixed ration and targeting the same gain (0.68 kg/d) were assigned to one of four treatments totaling 100 g/d of supplement with a ground corn carrier: MET (10 g/d), GAA (40 g/d), MET+GAA (10 g/d Met + 40 g/d GAA), and only ground corn carrier for control (CON). Supplementation began 63 d before breeding and concluded 63 d after breeding. Heifers pregnant with male offspring (CON, n = 10; MET, n = 8; GAA, n = 7; MET+GAA, n = 10) were slaughtered on d 63 of gestation. Transcript abundance was measured using RNA-Seq from extracted total RNA of fetal hindlimb samples (n = 35). The DEG analysis identified 227 upregulated and 121 downregulated genes from MET vs CON, 483 upregulated and 40 downregulated genes from GAA vs CON, and 672 upregulated and 34 downregulated genes from MET+GAA vs CON treated heifers (P ≤ 0.05). We identified 315 upregulated and 114 downregulated genes from MET vs GAA, 202 upregulated and 204 downregulated genes from GAA vs MET+GAA, and 35 upregulated and 133 downregulated genes from MET vs MET+GAA treated heifers (P ≤ 0.05). Over-representation analysis of DEGs highlighted immune response pathways that were found amongst the GAA vs CON, MET vs GAA, and GAA vs MET+GAA comparisons. Genes associated with cell inflammatory and immune response, including CD14, Toll-like receptor (TLR) 6, CD86, and TLR8, were upregulated in the GAA treatment. The TLR genes regulate expression of several pro-inflammatory cytokines, whereas CD genes are responsible for cell inflammatory response. Both are important for regulation of lipopolysaccharide (LPS)- binding protein, which plays a subsequent role in immune recognition when bound with LPS, resulting in genes from these families being recognized as markers for inflammatory response in beef cattle. Between MET vs CON and MET+GAA vs CON comparisons, 15 pathways including skeletal system development, alpha-amino acid catabolic process, and acylglycerol catabolic processes were shared. The FABP1 gene was upregulated in both aforementioned comparisons and has an integral role in transport and metabolism of fatty acids within cattle. Providing supplementation of methyl donors to the maternal environment results in over-representation of fetal muscle genes acting on immune response as well as fatty acid and amino acid metabolism. USDA is an equal opportunity provider and employer. [ABSTRACT FROM AUTHOR]

For the mature cow with low body condition scores (BCS), being too thin can accompany health issues, reduced pregnancy rates, more days to rebreeding, and decreased milk production resulting in lighter calves at weaning. In addition, reduced fat insulation in low BCS cows during the winter equates to additional feed requirements for warmth. The hypothesis of this study was that stress and immune factors contribute to low BCS in mature cows. The objective of this study was to determine whether there were differences in hematology parameters, hair cortisol concentrations, and plasma cytokine concentrations among animals with low body condition (BCS ≤ 4). Over a 3 yr study, we collected 62 pairs of cows which included cows with a BCS ≤ 4, and a matched control animal born in the same year with the same or similar breed composition from the same population of animals with a BCS of 5 or higher. Hematology parameters, cytokine concentration, and cortisol concentrations were analyzed using a model with BCS classification and sample year as fixed effects and age in years as a covariate. Hemoglobin, hematocrit, red blood cell and mean platelet volume were all less among the low BCS cows, and neutrophil count was greater (P < 0.05). Platelet, monocyte counts, mean corpuscular volume, and mean corpuscular hemoglobin tended to be greater in low BCS cows (0.05 < P ≤ 0.1), and lymphocyte count tended to be less. Hair cortisol concentrations, a longer-term measure of cortisol, tended to be greater in low BCS cows (P = 0.09). None of the 15 cytokines tested differed with BCS. The combination of reduced RBC parameters with greater neutrophils suggests that low BCS cows were responding to or were the reflection of some type of chronic stressor, such as a subclinical disease state or a physiologic stressor. This was also supported by the tendency for greater cortisol concentrations in low BCS cows. USDA is an equal opportunity provider and employer. [ABSTRACT FROM AUTHOR]