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The value of carinata, a non-food oilseed crop, has been demonstrated as a high-quality jet fuel alternative and successful cover crop in the southeastern U.S.; however, research is limited regarding carinata as an alternative for commonly used protein sources in livestock. Eighty-four Angus crossbred heifers were used in a generalized randomized block design to evaluate the effects of supplementing carinata meal compared with cottonseed meal on performance, intake, and digestibility in a backgrounding corn silagebased diet. Treatments included: corn silage only (CS), corn silage + Brassica carinata meal (BCM) at 10% (BCM10) or 20 % (BCM20) inclusion, or corn silage + cottonseed meal at 10% inclusion (CSM). Protein sources were mixed with corn silage prior to delivery and provided ad libitum, with individual intake measured using the GrowSafe system. Data were analyzed using Proc Glimmix of SAS. An effect of treatment was observed (P < 0.01) for final body weight (BW), average daily gain, and gain to feed ratio, where CS was least. Dry matter intake (DMI; kg/d) was greatest (P = 0.01) for BCM10 compared with CS, yet BCM20 and CSM did not differ from CS or BCM10. No effect of treatment was observed on DMI as a percentage of BW (P = 0.35) or residual feed intake (P = 0.94). Heifers receiving CSM had the greatest (P < 0.01) intake of dry matter (DM), organic matter (OM), neutral detergent fiber (NDF), and acid detergent fiber (ADF). Intake of crude protein (CP; P < 0.01) was least for CS and greatest for BCM20 and CSM, with BCM10 intermediate. Digestibility of all nutrients was least (P < 0.01) for CS, and greatest (P < 0.01) for BCM20 in CP and NDF, only, where BCM10 and CSM did not differ. Digestibility of DM, OM, and ADF was less (P < 0.01) in BCM10, greater in BCM20, while CSM did not differ between BCM10 and BCM20. Carinata supplemented at 10% diet DM performed similarly to cottonseed meal in backgrounding beef heifers fed a corn silage-based diet, thereby enhancing its value in the southeastern U.S. [ABSTRACT FROM AUTHOR]

The value of carinata, a non-food oilseed crop, has been demonstrated as a high-quality jet fuel alternative and successful cover crop in the southeastern U.S.; however, research is limited regarding carinata as an alternative for commonly used protein sources in livestock. Thirty-two Angus crossbred steers were used in a generalized randomized block design to evaluate the effects of supplementing carinata meal compared with cottonseed meal on performance, carcass characteristics, and meat sensory attributes in a finishing diet. Treatments included: either 90% basal diet + 10% inclusion of Brassica carinata meal (BCM) or 90% basal diet + 10% inclusion of cottonseed meal (CSM), on a dry matter (DM) basis. The basal diet consisted of 40% cracked corn, 35% soyhull pellets, 5% gin trash, 5% bermudagrass hay, and 5% vitamin-mineral supplement. Treatments were premixed before delivery and provided ad libitum, with individual intake measured using the GrowSafe system. Data were analyzed using Proc Glimmix of SAS. Protein source did not affect (P > 0.05) final body weight, dry matter intake, average daily gain, gain to feed ratio, or residual feed intake. Protein supplementation did not affect (P > 0.05) initial or final evaluations of longissimus muscle area (LMA), rib fat thickness (RF), and intramuscular fat performed via ultrasound during the performance portion of the experiment. Hot carcass weight (P = 0.10) dressing percentage (P = 0.61), LMA (P = 0.33), RF (P = 0.42), yield grade (P = 0.47), and marbling score (P = 0.89) were not affected by protein source. No effect of protein source was observed (P > 0.05) on slice shear force, juiciness, beef flavor, tenderness, connective tissue, off-flavor, crude fat, thaw loss, cook loss, lightness, redness, or yellowness. The frequency of Prime (P = 0.76), upper 2/3 Choice (P = 0.71), low Choice (P = 0.46), and Select (P = 0.34) USDA quality grades did not differ with protein source. carinata meal inclusion at 10% of the diet DM performed similarly to cottonseed meal in steers fed a finishing diet, thereby enhancing its value in the southeastern U.S. [ABSTRACT FROM AUTHOR]

Investigation of cellular responses to thermal heat stress can lead to identifying novel targets of intervention to tackle the increasing fertility decline due to climate change-associated seasonal heat stress. We aimed to study the response of granulosa cells to seasonal thermal stress. Dry beef cows (n=11) were kept together during the study and subjected to synchronization and stimulation for follicular dynamics. Ovum pick-up (OPU) was conducted on all animals in the winter and summer. Once OPU-fluid settled, cumulusoocyte-complexes (COCs) and granulosa cells were isolated form the OPU fluid and stored in a -80 freezer after snap freezing. In addition, blood samples and rectal temperature data were collected on each OPU. Environmental data were collected daily three weeks before each OPU using the Florida Automated Weather Network. Data was analyzed using the Glimmix procedure of SAS. Data are presented as mean ± standard error of the mean. RNA was extracted from five pools of granulosa cells followed by library preparation and sequencing (NovaSeq; Illumina). As expected, environmental conditions were contrasting: average air temperature (11.5°C vs. 27.5°C), average max air temperature (16.9°C vs. 33.7°C), relative humidity (83.5% vs. 82.3%), and temperature-humidity index (53.39 vs. 79.16) for winter and summer, respectively. Average rectal temperature was higher (P = 0.03) in summer (39.2 ± 0.2°C) than winter (38.8 ± 0.2°C). Of the total differentially expressed genes, granulosa cells during summer showed up and down regulation of 971 and 1038 transcripts, respectively compared to the winter season (Fold Change = -2 or = 2 and FDR p-value = 0.05). Those upregulated transcripts are found to be involved in cell cycle and division, regulation of cell death, steroid biosynthesis, progesterone mediated oocyte maturation and oocyte meiosis pathways. In conclusion, exposure of cows to thermal stress can induce significant alteration in transcriptome of granulosa cells which may have negative impact on follicular physiology. [ABSTRACT FROM AUTHOR]

This study investigated the relationship between thermotolerance and residual feed intake (RFI) in Bos-indicus influenced replacement beef heifers. Multiple individual vaginal temperatures (VT) collected during the summer in Florida were used to select the most (n = 14; thermotolerant) and least (n = 13; nonthermotolerant) heat tolerant heifers to undergo a feed efficiency test in the fall. The maximum initial VT difference between groups was of 0.19 and 1.2 ± 0.065 °C (P < 0.01) for thermotolerant and non-thermotolerant heifers, respectively. Heifers (398 ± 11.3 kg; approximately 720 d of age) were randomly allocated to four concrete-floored pens equipped with two GrowSafe feed bunks each and received a common ad libitum total mixed ration (16.9% crude protein and 52% total digestible nutrients) for 56 d (14 d adaptation and 42 d evaluation period). Body weight (BW) was collected on d -1, 0, 14, 28, 41, and 42, while VT was recorded (10 min intervals for 4 consecutive d) from d 29 to 32, using temperature probes placed intravaginally with a hormone-free controlled internal drug release device. Final BW, average daily gain (ADG), dry matter intake (DMI), DMI as a percentage of BW, RFI, and VT were analyzed as a completely randomized design. Final BW, ADG, DMI, and VT collected during the feeding period were not affected by thermotolerance phenotype (P = 0.42); however, heifers previously classified as thermotolerant had decreased RFI (P = 0.01; -1.32 vs. 1.27 ± 3.31 kg, respectively) and DMI as a percentage of BW (P = 0.01) when compared with nonthermotolerant heifers. In conclusion, Bos-indicus influenced replacement beef heifers previously classified as thermotolerant based on multiple vaginal temperature measurements collected throughout the summer had decreased residual feed intake when measured in the fall, indicating the potential of more heat tolerant heifers to be more feed efficient. [ABSTRACT FROM AUTHOR]

The value of carinata, a non-food oilseed crop, has been demonstrated as a high-quality jet fuel alternative and successful cover crop in the southeastern U.S.; however, research is limited regarding carinata as an alternative for commonly used protein sources in livestock. Eighty-four Angus crossbred heifers were used in a generalized randomized block design to evaluate the effects of replacing cottonseed meal with carinata meal on performance, intake, and digestibility in backgrounding corn silage-based diet. Treatments included: corn silage only (C), corn silage + Brassica carinata meal (BCM) at 10% (CS-BCM10) or 20 % (CS-BCM20) inclusion, or corn silage + cottonseed meal at 10% inclusion (CS-CSM). Protein sources were mixed on an as fed basis with corn silage prior to delivery and provided ad libitum, with individual intake measured using the GrowSafe system. Data were analyzed using Proc Glimmix of SAS. An effect of treatment was observed for final body weight (BW; P < 0.01), average daily gain (P < 0.01), and gain to feed ratio (P < 0.01), where CS was least. Dry matter intake (DMI; P = 0.01) was greatest for CS-BCM10. No effect of treatment was observed for residual feed intake (P = 0.94), time ruminating (P = 0.32), or DMI as a percentage of BW (P = 0.10). Intake of nutrients was greatest (P < 0.01) for CS-CSM, except crude protein (CP), which was least (P < 0.01) for CS. Dry and organic matter digestibility was decreased (P < 0.01) in CS but did not differ from CS-BCM10, whereas CP digestibility was greatest (P < 0.01) in CS-BCM20, and neutral and acid detergent fiber digestibility was least (P < 0.01) for CS. Carinata performed similarly to cottonseed meal in backgrounding beef heifers fed a corn silage-based diet, thereby enhancing its value in the southeastern U.S. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the effect of supplementation with an Aspergillus oryzae prebiotic (AOP) fed from ~30 d pre-partum until 30 d post-partum, on mineral concentrations in blood, liver, colostrum, and milk of multiparous beef cows. Thirty pregnant Angus crossbred cows were offered ad libitum Bermuda grass hay (Cynodon dactylon) plus a Vitaferm Concept-Aid (Biozyme Inc., St Joseph, MO) supplement at a rate of 112 g, containing (AOP; n = 15) or not (CTL; n = 15) an AOP. The treatments were delivered individually with a dried distillers grains-based premix at 454 g/d using an automated feeder (C-lock Inc, Rapid City, SD). For a minimum of 60 days prior to the expected calving date, the cows did not receive any mineral supplementation. Approximately 30 days prior to calving, right before supplementation began, blood and liver samples were collected, and mineral concentrations were used as a baseline. At calving (d 0) colostrum and blood samples were collected. Blood sampling, liver biopsies and milk collections were performed within one week after calving (d 7), and 30 days post-partum (d 30). All samples were analyzed to determine mineral concentration of P, Ca, Mg, Co, Cu, Fe, Zn, Mo, Mn, and Se. Concentrations of most micro minerals ranged from marginally adequate to deficient, with small improvement over time. Cows fed AOP had 11 and 14% lesser P and Se concentrations in serum, respectively (P < 0.05). Conversely, cows fed AOP had greater concentrations of Mn concentration in milk by 34% (P = 0.05), and greater Cu in milk by 74% on day 7 (P < 0.05). Feeding AOP did not affect (P > 0.10) the mineral concentrations in liver nor in colostrum. In conclusion, feeding AOP may affect mineral bioavailability in beef cows as evidenced by changes in milk mineral concentrations. [ABSTRACT FROM AUTHOR]

Previous evidence has suggested that fertilization and preimplantation embryonic development are sensitive periods that can be influenced by changes in maternal nutrition. We hypothesized that feeding rumen-protected methionine (RP-Met) during the periconceptional period will program bovine gestation in a manner that enhances fetal and postnatal growth. A total of 114 cows were fed a roughage-based diet and randomized to receive corn gluten supplemented with 15 g of RP-Met (RP-Met; Smartamine, Adisseo) or not (Con) from d -7 to +7 relative to artificial insemination (AI) with sex-sorted semen. Estrus synchronization was conducted using the 7-day CoSynch + CIDR protocol. Pregnancy diagnosis, embryo, and fetal morphology were conducted using transrectal ultrasonography 30, and 60 days after AI. After calving, 40 calves (Cont = 19; RP-Met = 21) were considered for birth weight (BW) analysis. Female calves (n=34) were weighed at 2 months of age. Pregnancy per AI at day 30 (Con = 50%, RP-Met = 55%) and day 60 (Con = 50%; RP-Met = 53.4%) were not different between groups (P ≥ 0.05). At 30 days of pregnancy, embryonic vesicle diameter (Con=11.0 ± 0.7 mm; RP-Met =11.6 ± 0.7 mm; P < 0.05) and circumference (Con=0.88 ± 0.09 cm2; RP-Met =0.99 ± 0.09 cm² P < 0.05) were larger in the RP-Met group but embryo length and abdominal cavity were not different between groups. No difference was observed in fetal morphology at d 60. A treatment by sex interaction was observed (P =0.04). Male calves (n=6) from cows fed RP-Met showed greater BW than those from Con group (Con=31.9 ± 2.3 kg; RP-Met =41.4 ± 2.3 kg) but no difference was observed in females (n=34). There was no difference in BW at 2 months of age between groups. In conclusion, using RP-Met increased embryonic vesicle diameter and circumference, and BW in males. [ABSTRACT FROM AUTHOR]