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The rarity of conjunctival melanoma has impeded progress in the management of patients with this cancer; however, much progress has occurred in recent years. Primary acquired melanosis is now differentiated histologically into hypermelanosis and conjunctival melanocytic intra-epithelial neoplasia, for which an objective reproducible scoring system has been developed. Mapping and clinical staging of conjunctival disease has improved. Adjunctive radiotherapy and topical chemotherapy have made tumour control more successful, with reduced morbidity. Genetic analyses have identified BRAF and other mutations, which may predict responsiveness to new chemotherapeutic agents, for example Vemurafenib, should metastatic disease develop. Multicentre studies are under way to enhance survival prediction by integrating clinical stage of disease with histological grade of malignancy and genetic abnormalities. Such improved prognostication would not only be more relevant to individual patients, but would also provide greater opportunities for basic science research. [ABSTRACT FROM AUTHOR]

The objective of this experiment was to determine if 2 doses of prostaglandin F2α (PGF) administered concurrently at controlled intravaginal drug release (CIDR) removal was an efficacious method for delivery of PGF in the 5-d CO-Synch + CIDR protocol. Postpartum beef cows (n = 2,465) from 13 herds in 8 states were enrolled in the 5-d CO-Synch + CIDR protocol and assigned to receive 2 doses of PGF (25 mg/dose) 8 h apart with the initial injection given at CIDR insert removal (8h-PGF), 2 doses (25 mg/dose) of PGF delivered in 2 injection sites, both administered at CIDR insert removal (Co-PGF), or a single 25-mg dose of PGF at CIDR insert removal (1x-PGF). Cows were fixed timed-artificially inseminated (FTAI) 72 h after CIDR removal concurrent with GnRH administration. Estrus-cycling status (54% cyclic) was determined by evaluation of progesterone in 2 blood samples collected before CIDR insertion. Determination of pregnancy was perfonned by transrectal ultrasonography 39 ± 0.1 d after FTAI and at least 35 d after the conclusion of the breeding season. Fixed timed-AI pregnancy rates were greater (P < 0.05) for the 8h-PGF (55%) than the 1x-PGF (48%) treatment, with the Co-PGF (51%) treatment intermediate and not different (P > 0.10) from the other treatments. Contrast analysis demonstrated that cows receiving 50 mg of PGF (8h-PGF and Co-PGF) had greater (P < 0.05) FTAI pregnancy rates than those receiving 25 mg (1x-PGF). Pregnancy rates to FTAI were greater (P < 0.05) in cyclic (55%) than noncyclic (47%) and greater (P< 0.05) in multiparous (>3 yr of age; 54%; n = 1,940) than primiparous cows (40%; n = 525). Luteolysis after PGF treatment was assessed in a subset of cows (n = 277) and treatment tended (P = 0.09) to affect the proportion of cows having luteolysis. The percentage of cows that had luteolysis was least in the 1x-PGF treatment (89%) and greatest in the 8h-PGF treatment (97%), with the Co-PGF treatment (94%) being intermediate. Breeding season pregnancy rate (88%) did not differ (P > 0.10) among treatments but was greater (P < 0.01) in multiparous (90%) than primiparous (78%) cows. In summary, 50 mg of PGF was required in the 5-d CO-Synch + CIDR protocol to maximize pregnancy rates; however, pregnancy rate did not differ when 50 mg of PGF was administered simultaneously with CIDR removal or split with 25 mg administered at 0 and 8 h after CIDR removal. [ABSTRACT FROM AUTHOR]

Two experiments were conducted to eval-uate the effects of feeding com modified wet distillers grain plus solubles (MWDGS) co-ensiled with direct-cut forage (DC) to beef steers, on feedlot performance and total tract digestibility. In Exp. 1, sixty-four cross-bred Angus steers (n = 64; 329 ± 43 kg) were blocked by BW and randomly assigned to 1 of 4 dietary treat-ments: 1) com-silage and soybean meal (CON), 2) DC co-ensiled with MWDGS (CO-EN), 3) haylage mixed with MWDGS at feeding (H+WDG), and 4) haylage mixed with dry distillers grains plus solubles at feed-ing (H+DDG). Steers were harvested when they reached an endpoint of 1.1 cm of 12th-rib back fat. In Exp. 2, four ruminally cannulated beef steers (initial BW = 556 ± 31 kg) were used in a 4 x 4 Latin square to evaluate digestibility of diets used in Exp. 1. Experimental peri-ods were 14 d in length with 10 d for diet adaptation and 4 d for sample collection. Three linear orthogonal con-trasts were used to compare effects of 1) CON vs. diets containing distillers grains (DGD), 2) CO-EN vs. diets where distillers grains were mixed at feeding (MIX), and 3) H+WDG vs. H+DDG. In Exp. 1, DMI was less (P < 0.001) for steers fed CON compared with those fed DGD and greatest (P < 0.001) for steers fed CO-EN compared with MIX. Com-silage- and soybean-meal- fed steers had more days on feed than those fed DGD (P = 0.001). Body weight gain (P = 0.02) was greater for CO-EN compared with MIX. Fat thickness at the 12th and 13th ribs was greater (P = 0.03) for DGD steers com-pared with CON steers. Hot carcass weight was greater (P = 0.03) for steers fed CO-EN compared with those fed MIX. Steers fed CON resulted in greater marbling scores (P = 0.01) compared DGD-fed steers. Longissi-mus muscle area was greater (P = 0.01) for CON-fed steers compared with all other treatments. In Exp. 2, no differences (P > 0.10) in DM, OM, or N intakes were observed. Apparent total tract DM (P = 0.01) and N (P = 0.02) digestibility were greatest in steers fed CON compared with all others. Steers fed DGD had less (P = 0.02) rumen NH3 concentrations compared with CON. The CON diet resulted in greater molar concentrations of VFA (P = 0.03) and decreased acetate to propionate ratio (P = 0.03) compared with all DGD. These data suggest that feeding MWDGS co-ensiled with direct-cut forage results in reduced diet digestibility but equal or greater feedlot performance and similar carcass and characteristics when compared with a com diet supple-mented with soybean meal and diets where MWDGS and DDGS were added at the mixer. [ABSTRACT FROM AUTHOR]

Three-year-old Angus × Gelbvieh beef cows nutritionally managed to achieve a BCS of 4 ± 0.07 (479.3 ± 36.3 kg of BW) or 6 ± 0.07 (579.6 ± 53.1 kg of BW) at parturition were used in a 2-yr experiment (n = 36/yr) to determine the effects of prepartum energy balance and postpartum lipid supplementation on cow and calf performance. Beginning 3 d postpartum, cows within each BCS were assigned randomly to be fed hay and a low-fat control supplement or supplements with either high-linoleate cracked safflower seeds or high-oleate cracked safflower seeds until d 60 of lactation. Diets were formulated to be isonitrogenous and isocaloric, and safflower seed supplements were provided to achieve 5% of DMI as fat. Ultrasonic 12th rib fat and LM area were lower (P < 0.001) for cows in BCS 4 compared with BCS 6 cows throughout the study. Cows in BCS 4 at parturition maintained (P = 0.02) condition over the course of the study, whereas cows in BCS 6 lost condition. No differences (P = 0.44 to 0.71) were detected for milk yield, milk energy, milk fat percentage, or milk lactose percentage because of BCS; however, milk protein percentage was less (P = 0.03) for BCS 4 cows. First-service conception rates did not differ (P = 0.22) because of BCS at parturition, but overall pregnancy rate was greater (P = 0.02) in BCS 6 cows. No differences (P = 0.48 to 0.83) were detected in calf birth weight or ADG because of BCS at parturition. Dietary lipid supplementation did not influence (P = 0.23 to 0.96) cow BW change, BCS change, 12th rib fat, LM area, milk yield, milk energy, milk fat percentage, milk lactose percentage, first service conception, overall pregnancy rates, or calf performance. Although cows in BCS of 4 at parturition seemed capable of maintaining BCS during lactation, the overall decrease in pregnancy rate indicates cows should be managed to achieve a BCS >4 before parturition to improve reproductive success. [ABSTRACT FROM AUTHOR]

Three-year-old Angus × Gelbvieh beef cows nutritionally managed to achieve a BCS of 4 ± 0.07 (479.3 ± 36.3 kg of BW) or 6 ± 0.07 (579.6 ± 53.1 kg of BW) at parturition were used in a 2-yr experiment (n = 36/yr) to determine the effects of prepartum energy balance and postpartum lipid supplementation on cow and calf performance. Beginning 3 d postpartum, cows within each BCS were assigned randomly to be fed hay and a low-fat control supplement or supplements with either high-linoleate cracked safflower seeds or high-oleate cracked safflower seeds until d 60 of lactation. Diets were formulated to be isonitrogenous and isocaloric, and safflower seed supplements were provided to achieve 5% of DMI as fat. Ultrasonic 12th rib fat and LM area were lower (P < 0.001) for cows in BCS 4 compared with BCS 6 cows throughout the study. Cows in BCS 4 at parturition maintained (P = 0.02) condition over the course of the study, whereas cows in BCS 6 lost condition. No differences (P = 0.44 to 0.71) were detected for milk yield, milk energy, milk fat percentage, or milk lactose percentage because of BCS; however, milk protein percentage was less (P = 0.03) for BCS 4 cows. First-service conception rates did not differ (P = 0.22) because of BCS at parturition, but overall pregnancy rate was greater (P = 0.02) in BCS 6 cows. No differences (P = 0.48 to 0.83) were detected in calf birth weight or ADG because of BCS at parturition. Dietary lipid supplementation did not influence (P = 0.23 to 0.96) cow BW change, BCS change, 12th rib fat, LM area, milk yield, milk energy, milk fat percentage, milk lactose percentage, first service conception, overall pregnancy rates, or calf performance. Although cows in BCS of 4 at parturition seemed capable of maintaining BCS during lactation, the overall decrease in pregnancy rate indicates cows should be managed to achieve a BCS >4 before parturition to improve reproductive success. [ABSTRACT FROM AUTHOR]

Milk fatty acid composition can be altered through maternal dietary manipulation. We hypothesized that changes in milk fatty acid composition could affect adipose tissue development in the suckling calf. Our objective was to determine the effects of maternal prepartum energy balance and postpartum lipid supplementation on mRNA transcripts of four lipogenic enzymes in adipose tissue of suckling calves. Three-year-old Angus × Gelbvieh beef cows nutritionally managed to achieve a BCS of 4 ± 0.07 (BW = 479.3 ± 36.3 kg) or 6 ± 0.07 (BW 579.6 ± 53.1 kg) at parturition were used in a 2-yr experiment (n = 36/yr). Beginning 3 d postpartum, cows within each BCS were assigned randomly to be fed hay and a low-fat control supplement or supplements with either high-linoleate cracked safflower seeds or high-oleate cracked safflower seeds until d 60 of lactation. Diets fed to cows were formulated to be isonitrogenous and isocaloric, with 5% of DMI as fat. After 61 d of suckling these cows, calf adipose tissue biopsies were taken from the tail head region for determination of mRNA abundance. Maternal BCS did not influence mRNA abundance for lipoprotein lipase (LPL; P = 0.90), acetyl-CoA carboxylase (ACC; P = 0.96), stearoyl-CoA desaturase (SCD; P = 0.97), or fatty acid synthase (FAS; P = 0.25). Likewise, mRNA abundance of LPL (P = 0.94), ACC (P = 0.93), SCD (P = 0.98), and FAS (P = 0.86) did not differ in adipose tissue of calves suckling cows fed the various dietary treatments. We conclude that neither maternal BCS nor milk fat compositional changes occurring from 5% of DMI as fat from oil seeds during the first 60 d of lactation in beef cows was great enough to impact lipogenic enzyme mRNA abundance in adipose tissue of their suckling calves. [ABSTRACT FROM AUTHOR]

This study was conducted to determine effects of pre-synchronization of ovulation timing among heifers and delayed fixed-time artificial insemination (TAI) with sex-sorted semen on proportion of heifers pregnant after TAI (PR/AI). Heifers were assigned to one of eight treatments: 1 and 2), 7-d CO-Synch + CIDR treatment regimen with administration of gonadotropin-releasing hormone and a CIDR insert on Day 0, prostaglandin F 2α (PGF) at CIDR removal on Day 7, and TAI occurring 54 h later with conventionally processed (CTRL54-CNV) or sex-sorted semen (CTRL54-SEX); 3 and 4), same as CTRL54 but TAI delayed to 72 h with conventionally processed (CTRL72-CNV) or sex-sorted semen (CTRL72-SEX); 5 and 6), same as CTRL54 but additional administration of PGF on Day -7 and TAI with conventionally processed (PRE54-CNV) or sex-sorted semen (PRE54-SEX); 7 and 8), same as PRE54 treatments but TAI delayed to 72 h with conventionally processed (PRE72-CNV) or sex-sorted semen (PRE72-SEX). Proportion of heifers pregnant after TAI was greater (P ≤  0.02) with conventionally processed semen compared with sex-sorted semen, yet PR/AI did not differ (P =  0.14) between heifers in PRE72-CNV and PRE72-SEX groups. There were greater PR/AI in the PRE72-SEX (P =  0.03) than CTRL54-SEX group (46.1 % and 36.9 %) and there was no difference (P =  0.31) in PR/AI between CTRL54-CNV and PRE72-SEX groups (50.4 % and 46.1 %). In conclusion, pre-synchronization of ovulation timing among heifers combined with delayed TAI resulted in increased PR/AI with sex-sorted semen compared with the 7-d CO-Synch+CIDR treatment regimen., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Previous studies have demonstrated that a decrease in nutrition immediately following AI reduces pregnancy success in beef heifers. The objective of this experiment was to determine if nutrient restriction following AI impacted early embryonic development among non-super ovulated heifers. Beef heifers in eight replications (Rep; Rep 1; n = 14, Rep 2; n = 15, Rep 3; n = 15, Rep 4; n = 14, Rep 5; n = 15, Rep 6; n = 15, Rep 7; n = 25, Rep 8; n = 25) across two locations (UMN, SDSU) were developed in a dry-lot and fed 125% NRC requirements from weaning to timed-AI (d 0). Heifers were timed-AI to a single sire in all replications. Immediately following AI, heifers were assigned, based on age, weight, and estrous response to one of two post-AI nutritional treatments. Half the heifers in each replication continued on the pre-insemination diet, serving as the control treatment (CON) and the remaining heifers were restricted to a sub-maintenance diet (RES). At UMN, heifers in the RES treatment were fed the same diet, but intake was limited to 80% NE m , while at SDSU, DMI remained the same, but diet composition was altered with the addition of straw to reduce NE m to 50% of requirements. On d 6, single embryos were collected nonsurgically and recovered embryos (CON; n = 46, RES; n = 42) were evaluated to determine quality (grade 1-9) and stage (1-4). Embryos were then stained and evaluated to determine the number of dead cells and total blastomeres. In Reps 1 through 6, concentrations of IGF-1 were assessed on d 0 and 6 and progesterone concentrations on d 4 and 6. Data were analyzed using the Mixed procedures of SAS. There were no treatment by Rep or treatment by location interactions for any embryo parameter evaluated, thus all data were pooled. Embryo stage and quality were improved (P < 0.01) in the CON (4.4 ± 0.16, 2.2 ± 0.19, respectively) compared to RES treatment (3.7 ± 0.16, 2.9 ± 0.19, respectively). Embryos in the CON treatment had greater total blastomeres (66.9 ± 5.05; P < 0.01) and tended to have a greater percentage of live cells (P < 0.10; 80.9 ± 4.19%) compared to RES (47.9 ± 5.41; 69.7 ± 4.39%, respectively). Progesterone and IGF-1 concentrations did not differ between treatments. In summary, nutrient restriction for 6 days immediately following AI resulted in poorer quality embryos that were delayed in stage of development, suggesting that immediate changes in nutritional status after insemination can alter early embryonic development., (Copyright © 2016 Elsevier Inc. All rights reserved.)

The objective of this study was to determine the effects of maternally supplemented natural- or synthetic-source vitamin E on suckling calf performance and immune response. In a 2-yr study, one hundred fifty-two 2- and 3-yr-old, spring-calving, Angus-cross beef cows were blocked by age, BW, and BCS into 1 of 3 isocaloric, corn-based dietary supplements containing 1) no additional vitamin E (CON), 2) 1,000 IU/d of synthetic-source vitamin E (SYN), or 3) 1,000 IU/d of natural-source vitamin E (NAT). Maternal supplementation began approximately 6 wk prepartum and continued until the breeding season. Colostrum from cows and blood from calves was collected 24 h postpartum for analysis of IgG concentration as an indicator of passive transfer and circulating alpha-tocopherol concentration. At 19 d of age, blood was collected from calves to determine the expression of CD14 and CD18 molecules on leukocytes. At 21 and 35 d of age, humoral immune response was measured by a subcutaneous injection, in the neck, with ovalbumin (20 mg; OVA) and blood samples collected weekly until d 63 of age to determine antibodies produced against OVA. At d 63 of age, calves were administered an intradermal injection of OVA (1 mg) in the neck to assess cell-mediated immunity, which was determined on d 65 of age by measuring nodule size with calipers. Circulating alpha-tocopherol concentrations were increased at both 24 h (P = 0.001) and at the day of initial OVA challenge (P < 0.001) in SYN and NAT compared with CON calves. No differences were detected (P > 0.05) for calf birth BW, ADG, or weaning BW. There were no differences (P > 0.05) in calf serum total IgG or cow colostrum total IgG at 24 h or presence of CD14 and CD18 receptors at d 19 of age. The NAT calves had a greater antigen response to OVA at d 63 than SYN calves (P = 0.01; treatment x day interaction). As an indicator of cell-mediated immunity to OVA, nodule size at 65 d of age was not affected (P = 0.92) by maternal dietary supplementation. In conclusion, calves suckling cows supplemented with natural- and synthetic-source vitamin E had increased circulating concentrations of alpha-tocopherol at 24 h, which appeared to continue throughout maternal supplementation; however, calf immune function and performance were not affected.

The objective was to determine the effects of natural- or synthetic-source vitamin E on reproductive efficiency in Angus-cross beef cows. In Exp. 1, one hundred fifty-two cows were fed hay and corn silage based diet and assigned to 1 of 3 dietary supplements (3 pens/treatment): 1) containing no additional vitamin E (CON), 2) formulated to provide 1,000 IU x d(-1) of synthetic-source vitamin E (SYN; all-rac or dl-alpha-tocopherol acetate), or 3) formulated to provide 1,000 IU x d(-1) of natural-source vitamin E (NAT; RRR or D-alpha-tocopherol acetate). In Exp. 2, seventy-five cows (2 reps/treatment) were assigned to similar treatments as Exp. 1; however, a vitamin-mineral supplement was offered for ad libitum intake and vitamin intake was calculated from predicted mineral intakes. Cows grazed pastures rather than being fed hay and corn silage as in Exp. 1. In Exp. 1 and 2, supplementation began 6 wk prepartum and continued until initiation of the breeding season. Blood samples were collected at calving (Exp. 1) or breeding (Exp. 2) to determine alpha-tocopherol concentration and weekly beginning 4 wk postpartum (Exp. 1) or 7 and 14 d before estrus synchronization (Exp. 2) to determine return to estrus via progesterone concentration. Cows were synchronized and bred by AI based on heat detection; nonresponding cows were time bred (AI) 66 h after PGF(2 alpha) injection, and cows returning to estrus after AI were bred by natural service. In Exp. 1, cows supplemented with NAT and SYN had greater (P < 0.001) serum concentrations of alpha-tocopherol at calving compared with CON cows. Dietary supplement did not affect (P >or= 0.55) the percentage of cows cycling before synchronization or the number of days to return to estrus by cows that resumed estrus before synchronization. Cows supplemented with SYN tended to have greater first service conception rates compared with CON and NAT (P = 0.09); however, first plus second services combined and overall conception rates were not affected (P >or= 0.23). In Exp. 2, NAT cows had greater (P = 0.002) concentrations of alpha-tocopherol at breeding, whereas there was no difference (P > 0.05) between SYN and CON. Supplementation of SYN or NAT did not affect (P >or= 0.17) days to resumption of estrus before breeding, first service, first plus second services combined, or overall conception rates. These data suggest that supplementation of SYN or NAT source vitamin E increased alpha-tocopherol concentration in cows; however, effects on reproductive efficiency are minimal.

Cyathostomins are recognised as the primary parasitic pathogens of horses. Despite the use of benzimidazole (BZ) anthelmintics in horses for more than 40 years and widespread drug resistance in the field, the mechanisms of resistance to this drug class in cyathostomins are not fully understood. The results presented here constitute a detailed comparison of beta tubulin gene mutations and mRNA transcript levels in populations of BZ-susceptible (BZ-S) and -resistant (BZ-R) cyathostomins. Full-length cDNA sequences were generated from individual parasites of four (n=24) and two (n=19) cyathostomin species for isotypes 1 and 2, respectively. Levels of intra- and inter-specific nucleotide sequence variation were comparable with previous findings and single amino acid substitutions were observed at several locations. On comparison of BZ-S and BZ-R parasites, differences were consistently observed at only two sites, codons 167 and 200 of the beta tubulin isotype 1 gene. Four populations of parasites were genotyped at these two loci by pyrosequencing; one that was fenbendazole (FBZ)-sensitive (FBZ-rS), two that were FBZ-resistant (FBZ-R1 and -R2) and one that was oxibendazole-resistant (OBZ-R), as previously assessed by faecal egg count reduction tests. This analysis revealed statistically significant differences between FBZ-rS and FBZ-R populations at both loci and this was highly significant for codon 167. For the OBZ-R population, the only significant difference compared with the FBZ-rS population was observed at codon 200. These observations suggest that mutations at codons 167 and 200 are important in BZ resistance and raise the possibility that selection at different loci may occur in FBZ- and OBZ-resistant parasites. Multiple parasites (n=158) were genotyped for both codons 167 and 200, the majority of which showed homozygous 'resistant' mutations at one locus only and none showed homozygous 'resistant' genotypes at both loci. No significant differences in mRNA levels of beta tubulin isotypes 1 and 2 were observed between the FBZ-rS and FBZ-R1 populations.