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Heat stress (HT) and photoperiod affect milk production and immune status of dairy cows. The objective was to evaluate the effects of HT abatement prepartum under controlled photoperiod on hepatic metabolic gene expression and cellular immune function of periparturient Holstein cows (n = 21). Cows were dried off 46 d before expected calving date and assigned to treatments by mature equivalent milk production. The treatments were 1) HT and 2) cooling (CL), both imposed during a photoperiod of 14L:10D. Rectal temperature was measured twice daily, whereas respiration rate was measured 3 times/wk at 1500 h during the entire dry period. After calving, cows were housed in a freestall barn with cooling, and milk yield was recorded daily up to 140 d in milk. Liver samples were taken at dry off, −20, 2, and 20 d relative to calving by biopsy. Under a similar schedule, neutrophil function was determined in blood of cows on HT (n = 12) and CL (n = 9). Blood samples were taken on −46, −32, −18, 0, 14, 28, and 42 d relative to calving for measurement of metabolites and were collected twice daily from −7 to 2 d relative to calving for prolactin (PRL) analysis. The HT cows had greater concentrations of PRL at 0 d relative to calving (150 vs. 93; SEM = 11 ng/mL) and had higher afternoon rectal temperatures (39.4 vs. 39.0; SEM = 0.04°C) and elevated respiration rates (78 vs. 56; SEM = 2 breaths/min) during the prepartum period compared with CL cows. Relative to HT cows, CL cows had greater hepatic expression of PRL-R, SOCS-3, and CAV-1 mRNA. Neutrophil oxidative burst was greater in CL cows relative to HT cows at 2 d (61 vs. 42; SEM = 6%) and at 20 d (62 vs. 49; SEM = 5%) relative to calving, and phagocytosis was greater in CL cows at 20 d (47 vs. 33; SEM = 4%) relative to calving compared with HT cows. Humoral response, as measured by IgG secretion against ovalbumin challenge, was greater for CL cows at −32 d (0.44 vs. 0.33; SEM = 0.05 OD) and −21 d (0.60 vs. 0.50 ± 0.04 OD) relative to calving compared with HT cows. These results suggest that HT abatement during the dry period improved innate and acquired immune status as measured by neutrophil function and immunoglobulin secretion against ovalbumin challenge, and altered hepatic gene expression related to PRL signaling in the periparturient period or subsequent lactation. [ABSTRACT FROM AUTHOR]

Environmental factors, especially temperature and light exposure, influence the health and productivity of dairy cows during lactation, possibly via similar physiological mechanisms. For example, heat stress is a critical component of decreased milk yield during summer. However, less is known about the effect of heat stress during the dry period. The objective of this study was to evaluate the effects of heat stress prepartum under a controlled photoperiod on lactation performance and hepatic metabolic gene expression of periparturient multiparous Holstein cows (n = 16). Cows were dried off approximately 46 d before expected calving date and assigned to treatment randomly after blocking by mature equivalent milk production and parity. Treatments consisted of either heat stress (HT) or cooling (CL) with fans and sprinklers, both under a photoperiod of 14L:10D. Rectal temperature was measured twice daily during the dry period. After calving, cows were housed in a freestall barn with cooling devices, and milk yield was recorded daily up to 210 d in milk. Blood samples were taken from dry off until +42 d relative to calving for metabolites and from -2 until +2 d relative to calving for hormone analysis. Daily dry matter intake was measured from -35 to +42 d relative to calving. Liver biopsies were collected at dry off, -20, +2, and +20 d relative to calving for cows on HT (n = 5) and CL (n = 4) to measure mRNA expression of suppressors of cytokine signaling-2 (SOCS-2), insulinlike growth factor binding protein-5 (IGFBP-5), a key transcription factor in lipid biosynthesis (SREBP-1c), and enzymes of lipid metabolism (FASN, ACACA, and ACADVL) by real-time quantitative PCR. Heat stress increased rectal temperatures (39.2 vs. 38.8°C), plasma prolactin concentrations at -1 (171 vs. 79 ng/ mL) and 0 d (210 vs. 115 ng/mL) relative to calving, and decreased dry matter intake at 0 and +14 d relative to calving and 3.5% fat-corrected milk postpartum (26.1 vs. 35.4 kg/d) compared with CL cows. Relative to CL cows, hepatic mRNA expression of SOCS-2 and IGFBP-5 was downregulated in HT cows. Expression of ACADVL was upregulated in CL cows at d +2 but downregulated at d +20 relative to HT cows. Concentrations of C16:0 and cis C18:1 were greater in the milk and liver of CL cows compared with HT cows, which reflects greater lipid mobilization. These results suggest that heat-stress abatement in the dry period improves subsequent lactation, possibly via suppression of plasma prolactin surge around calving, SOCS-2 expression, and regulation of hepatic lipid metabolism. [ABSTRACT FROM AUTHOR]

Reports on a prospective study on the effectiveness of sulphasalazine for the treatment of Melkersson-Rosenthal syndrome (MRS), a disease characterized by the triad of symptoms labial such as facial edema, fissured tongue and facial palsy. Finding that sulphasalazine is the drug of choice in granulomatous disorders.

Cell wall fragments from both yeast-like and mycelial forms of the dimorphic fungus Mucor rouxii were used as enzymatic preparations to study the synthesis and role of prenyl-phospho-sugars in these systems. In the presence of GDP ['4C] mannose two main products were formed. One of them was characterized as dolichol-monophosphate β-mannose on the following basis: solubility in organic solvents, behaviour upon paper chromatography, DEAF cellulose column chromatography, mild acid hydrolysis, alkali treatment, catalytic reduction and phenol degradation. The other product was identified as a glicoprotein containing a single mannose unit linked to a serine or threonine residue. It was degraded with pronase and by mild NaOH-NaBH treatment all the radioactivity was released as free mannitol. When UDP[C] glucose was employed as sugar donor two butanol soluble components were isolated. One of them (25%) was characterized as dolichol-monophosphate-ß-glucose on the basis of the same criteria as described above. The other one (75%) was neutral and was not studied in detail. Mycelial enzymes were about 40 times more active in the synthesis of the dolichol derivatives. In addition, large amounts of glycogen were detected. The role that both dolichol derivatives might play in glycoprotein biosynthesis is discussed. [ABSTRACT FROM AUTHOR]

No presente texto discutimos como palavras polissêmicas e homônimas são acessadas e qual o papel do contexto durante a etapa de acesso. Trabalhos clássicos como Swinney (1979) e Tanenhaus et al. (1979) defendem a hipótese do acesso múltiplo, para a qual o contexto age apenas tardiamente no acesso lexical de palavras ambíguas. Já Tabossi e Zardon (1993) e Simpson (1994) defendem a hipótese do acesso seletivo, segundo a qual apenas o sentido especificado pelo contexto é acessado na leitura de uma palavra ambígua. Para verificar a validade dessas hipóteses no acesso a palavras polissêmicas e homônimas realizamos três experimentos de cross-modal priming. Os resultados corroboram a hipótese do acesso múltiplo. No que concerne à relação entre polissemia e homonímia, nossos achados fornecem evidências para a hipótese de que palavras polissêmicas e homônimas são acessadas da mesma forma, mesmo que haja mais sentidos diacronicamente associados às polissemias

The present study was conducted to assess the testicular structure and germ cell ultrastructure of Hypophthalmus marginatus during spermatogenesis. Semen and sections of the mid-region of the testis were collected, processed, and analyzed using optical and electron microscopy. Macroscopically, the testes of H. marginatus were filiform, and the testicular parenchyma was composed of spermatogenic cells that proliferated, organized within spermatic cysts. During spermiogenesis, spermatids had no nuclear rotation. The proximal centriole was perpendicular to the distal centriole, characteristic of type III spermiogenesis. Spermatozoa were released into the lumen of the seminiferous tubules and had an ovoid head without an acrosome, condensed nucleus, and shallow nuclear fossa. The midpiece was short, with a single long flagellum. The flagellum had the typical axoneme structure, with nine pairs of peripheral and a central pair of microtubules. The thin end piece comprised only peripheral microtubules. Spermatogenesis in H. marginatus features filiform testes, cystic spermatogenesis, and type III spermiogenesis. [ABSTRACT FROM AUTHOR]

In an effort to improve the efficiency of dairy cattle production, the University of Florida provides producers with information, support and leadership for the continued economic development and sustainability of the dairy industry. Dietary supplementation of lipids allowed for improved production and reproductive performance of dairy cows, especially during the summer. Other contributions in nutrition include use of citrus pulp as an energy source and DCAD diets for cows in the transition period and the realization of the importance of mineral nutrition in the summer. A greater understanding of the physiology and endocrinology of the estrous cycle and ovarian function has led to the development of reproductive management tools for synchronizing estrus for timed insemination. In addition, pioneering work led to the discovery of interferon-tau as the key protein involved in maternal recognition of pregnancy. Shortening of the dry period increased milk income and reduced the incidence of disorders associated with transition cows as they initiate a new lactation. Studies with bST in lactating cows helped with its promotion and utilization to increase milk yield and allowed for increased profit margins of dairy enterprises. Realization that heat stress reduced the establishment and maintenance of pregnancy and lowered milk production led to studies to improve the ability of lactating cows to regulate their body temperature. These efforts included improving housing conditions through the use of shade, fans, sprinklers, water application rates, and cooling ponds and identification of the "slick hair" gene involved in thermoregulation. Incorporation of timed artificial insemination to eliminate heat detection and utilization of timed embryo transfer to bypass the sensitivity of early embryos to elevated temperature are management strategies used by producers to increase pregnancy rates in the summer. The Dairy Science program continues to improve dairy cattle efficiency while maximizing milk production and developing solutions for the changing needs of the dairy industry. [ABSTRACT FROM AUTHOR]

The objective was to evaluate how dietary fat sources enriched with oleic, trans-octadecenoic, linoleic, or linolenic acids affected the plasma and liver fatty acid profiles of Holstein heifers (n = 22) and cows (n = 32) during the summer season. Fat supplements were the following: 1) sunflower oil (SFO - Trisun, Humko Oil, 80% C18:1), 2) Ca salt of trans-octadecenoic acids (TRANS- EnerG TR, Virtus Nutrition, 57% trans 6-12), 3) Ca salt of vegetable oils (MEGRMegalac- R, Church & Dwight Co, 30% C18:2), and 4) linseed oil (LSO- Archer Daniels Midland, 56% C18:3 and 16% C18:2). Supplemental fats were fed at 1.35% of dietary DM beginning at 29 d prior to expected calving date. After calving, fats were fed at 1.5% (oils) and 1.75% (Ca salts) of dietary DM for 15 wk. Three blood samples collected on a Monday-Wednesday-Friday schedule between 21 and 28 DIM were analyzed for fatty acids using gas chromatography. Liver samples were taken via biopsy on 2, 14±2, and 28±2 DIM, immediately frozen in liquid nitrogen and kept at -800C for fatty acid analysis. Feeding high oleic sunflower oil did not affect the C18:1 concentrations of plasma (12.35%) or liver (21.8%). Cows fed TRANS fats had greater concentrations of plasma C18:1 trans isomers in liver tissue (1.0, 1.4, 1.0, and 1.0% for diets 1, 2, 3, and 4, respectively). Concentrations of C18:2 were greater in cows fed MEGR (44.4%) compared to cows fed LSO (41.8%) but were not different from that of cows fed SFO (43.4%) or TRANS (45.2%). Cis-9, trans-11 CLA was greater in plasma (0.13, 0.13, 0.16, and 0.14%) and liver (0.41, 0.43, 0.50, and 0.47%) of cows fed MEGR compared to those fed SFO or TRANS. Cows fed LSO had greater concentrations of C18:3 (2.4, 2.5, 2.3, and 4.9%; 0.9, 0.9, 1.0, and 1.4%) and C20:5 (0.5, 0.5, 0.5, and 0.7%; 0.6, 0.6, 0.5, and 0.9%) in plasma and liver, respectively. Feeding dietary fats enriched with particular fatty acids resulted in increased concentrations of those fatty acids in the plasma and liver. [ABSTRACT FROM AUTHOR]

The objective was to evaluate how dietary fat sources of oleic, transoctadecenoic, linoleic, or linolenic acids affected bST, IGF-1, and PGF metabolite (PGFM) concentrations in plasma of Holstein heifers (n = 22) and cows (n = 32) during the summer season. Fat supplements were the following: 1) sunflower oil (SFO; Trisun, Humko Oil, 80% C18:1), 2) Ca salt of trans-octadecenoic acids (TRANS; EnerG TR, Virtus Nutrition, 57% trans 6-12 C18:1), 3) Ca salt of vegetable oils (MEGR; Megalac-R, Church & Dwight Co, 30% C18:2), and 4) linseed oil (LSO- Archer Daniels Midland, 56% C18:3 and 16% C18:2). Supplemental fats were fed at 1.35% of dietary DM beginning at 29 d prior to expected calving date. After calving, fats were fed at 1.5% (oils) and 1.75% (Ca salts) of dietary DM for 15 wk. Blood samples were taken thrice weekly during 7 wk for measurement of IGF-1 and bST and for the first 14 DIM for PGFM. Mean concentrations of plasma IGF-1 tended to be greater (P = 0.08) in heifers compared to cows (135 vs. 124 ng/ml) but did not differ among treatment groups (122, 135, 124, and 137 ng/ml for diets 1, 2, 3, and 4 respectively). Concentrations of IGF-1 increased at a faster rate for animals fed polyunsaturated fats compared to those fed monounsaturated fats. Mean concentrations of bST were not different among treatments. Plasma concentrations of bST decreased from 7.0 to 4.1 ng/ml over DIM for primiparous cows except those fed MEGR, which increased from 7.3 to 8.3 ng/ml. For multiparous cows, bST concentrations also decreased over time but those fed MEGR decreased at a faster rate (treatment by parity by DIM interaction). Cows fed TRANS had a higher initial plasma concentration of PGFM (4065 vs. 2408 ng/ml) and decreased at a faster rate than cows fed SFO but both reached baseline by 9 DIM. The PGFM concentrations of cows fed MEGR decreased at a slower rate compared to cows fed LSO, reaching baseline 2 d later. Dietary fatty acids alter hormonal status of lactating dairy cows. [ABSTRACT FROM AUTHOR]

Heat stress during the dry period negatively affects hepatic metabolism and cellular immune function during the transition period, and milk production in the subsequent lactation. However, the cellular mechanisms involved in the depressed mammary gland function remain unknown. The objective of the present study was to determine the effect of heat stress during the dry period on various indices of mammary gland development of multiparous cows. Cows were dried off approximately 46 d before expected calving and randomly assigned to 2 treatments, heat stress (HT, n = 15) or cooling (CL, n = 14), based on mature equivalent milk production. Cows in the CL treatment were provided with sprinklers and fans that came on when ambient temperatures reached 21.1°C, whereas HT cows were housed in the same barn without fans and sprinklers. After parturition, all cows were housed in a freestall barn with cooling. Rectal temperatures were measured twice daily (0730 and 1430 h) and respiration rates recorded at 1500 h on a Monday-Wednesday-Friday schedule from dry off to calving. Milk yield and composition were recorded daily up to 280 d in milk. Daily dry matter intake was measured from dry off to 42 d relative to calving. Mammary biopsies were collected at dry off, -20, 2, and 20 d relative to calving from a subset of cows (HT, n = 7; CL, n = 7). Labeling with Ki67 antigen and terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick-end labeling were used to evaluate mammary cell proliferation and apoptosis, respectively. The average temperature-humidity index during the dry period was 76.6 and not different between treatments. Heat-stressed cows had higher rectal temperatures in the morning (38.8 vs. 38.6°C) and afternoon (39.4 vs. 39.0°C), greater respiration rates (78.4 vs. 45.6 breath/min), and decreased dry matter intake (8.9 vs. 10.6 kg/d) when dry compared with CL cows. Relative to HT cows, CL cows had greater milk production (28.9 vs. 33.9 kg/d), lower milk protein concentration (3.01 vs. 2.87%), and tended to have lower somatic cell score (3.35 vs. 2.94) through 280 d in milk. Heat stress during the dry period decreased mammary cell proliferation rate (1.0 vs. 3.3%) at -20 d relative to calving compared with CL cows. Mammary cell apoptosis was not affected by prepartum heat stress. We conclude that heat stress during the dry period compromises mammary gland development before parturition, which decreases milk yield in the next lactation. [ABSTRACT FROM AUTHOR]

Dietary sources of fatty acids were evaluated for their influence on oocyte quality and follicular development using 54 lactating cows in summer. Fat supplements were 1) sunflower oil (80% cis 18:1), 2) Ca salt of transoctadecenoic acids (57% trans 18:1), 3) Ca salt of vegetable oils (30% 18:2), and 4) linseed oil (56% 18:3 and 16% 18:2). Fats were fed at 1.35% of dietary dry matter beginning at 5 wk prior to expected calving date and at 1.5% (oils} and 1.75% (Ca salts) of dietary dry matter for 15 wk after parturition. Four days following a programmed induced ovulation, 5 transvaginal oocyte aspirations were performed 3 or 4 d apart. Three days after the last aspiration, PGF2α was injected, followed 3 d later by a GnRH injection and a timed artificial insemination (d 0) 16 to 20 h later. For the first 4 aspirations, oocytes grading 1 or 2 were used for in vitro embryo production. Total cell number and the proportion of terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL)-positive blastomeres were analyzed at d 8. At the fifth aspiration, the occurrence of metaphase II, group II caspase activity, and TUNEL labeling were determined after oocyte maturation. A total of 1,011 oocytes were collected. The proportion of oocytes with high caspase activity was greater for grade 3 compared with grades 1 and 2 (37.5 vs. 1.54 and 1.61%). Feeding polyunsaturated fatty acids, as compared with monosaturated fatty acids, failed to affect oocyte quality, as demonstrated by subsequent embryo development. Cows fed 18:2- or 18:3-enriched diets had a larger preovulatory follicle at insemination and subsequent volume of the corpus luteum compared with those fed cis 18:1 or trans 18:1 diets (!6.8, 16.2 vs. 15.0, 14.9 ± 0.7 mm; 7,323, 8,208 vs. 6,033, 5,495 ± 644 mm³, respectively). The previously documented benefits of polyunsaturated fatty acids on reproductive performance appear to reflect actions at alternative biological windows in lactating dairy cows. [ABSTRACT FROM AUTHOR]

Heat stress (HT) during the dry period compromises mammary gland development, decreases future milk production, and impairs the immune status of dairy cows. Our objective was to evaluate the effect of cooling HT cows during the dry period on gene expression of the mammary gland and peripheral blood mononuclear cells (PBMC). Cows were dried off 46 d before their expected calving and assigned to 2 treatments, HT or cooling (CL). Cows in the CL group were cooled with sprinklers and fans whereas HT cows were not. After parturition, all cows were housed in a freestall barn with cooling. The PBMC were isolated at dry-off and at -20, 2, and 20 d relative to calving from a subset of cows (HT, n = 9; CL, n = 10), and mammary biopsies were taken at the same intervals (HT, n = 7; CL, n = 6) for RNA extraction. Gene expression was assessed using a custom multiplex gene expression assay based on traditional reverse transcription-PCR. Genes involved in prolactin (PRL) signaling [PRL receptor long form, PRL receptor short form, suppressor of cytokine signaling (SOCS)2, SOCS3, IGF2, IGF binding protein 5, and cyclin D1], fatty acid metabolism (acetyl-CoA carboxylase a (ACACA) and lipoprotein lipase (LPL)], and IGF1 were evaluated in mammary tissue, and genes related to fatty acid metabolism [ACACA, fatty acid synthase (FASN), and LPL], cytokine production [IL6, IL8, and tumor necrosis factor (TNF)], and IGF1 were evaluated in PBMC. No differences were observed in PRL signaling or fatty acid metabolism gene expression in the mammary gland. In PBMC, HT cows had greater mRNA expression of IGF1 and TNF during the transition period relative to CL and upregulated IL8 and downregulated FASN mRNA expression at 2 d relative to calving. We conclude that cooling HT cows during the dry period alters expression of genes involved in cytokine production and lipid metabolism in PBMC. [ABSTRACT FROM AUTHOR]