Dietary supplementation of rumen native microbes improves lactation performance and feed efficiency in dairy cows.

The objectives of this study were to determine the effects of 2 dietary microbial additives on productive performance and feed efficiency when supplemented to diets of Holstein cows. One hundred seventeen Holstein cows were enrolled at 61 d (31-87 d) postpartum in a randomized complete block design experiment. Cows were blocked by parity group, as nulliparous or multiparous cows and, within parity, by pretreatment ECM yield. Within block, cows were randomly assigned to one of 3 treatments administered as top-dress for 140 d. Treatments consisted of either 100 g of corn meal containing no microbial additive (CON; 15 primiparous and 25 multiparous), 100 g of corn meal containing 5 g of a mixture of Clostridium beijerinckii and Pichia kudriavzevii (G1; 4 × 107 cfu of C. beijerinckii and 1 × 109 cfu of P. kudriavzevii; 14 primiparous and 24 multiparous), or 100 g of corn meal containing 5 g of a mixture of C. beijerinckii, P. kudriavzevii, Butyrivibrio fibrisolvens, and Ruminococcus bovis (G2; 4 × 107 cfu of C. beijerinckii, 1 × 109 cfu of P. kudriavzevii, 1 × 108 cfu of B. fibrisolvens, and 1 × 108 cfu of R. bovis; 15 primiparous and 24 multiparous). Intake of DM, milk yield, and BW were measured daily, whereas milk composition was analyzed at each milking 2 d a week, and body condition was scored twice weekly. Milk samples were collected on d 60 and 62 in the experiment and analyzed for individual fatty acids. The data were analyzed with mixed-effects models with orthogonal contrast to determine the effect of microbial additive (MA; CON vs. 1/2 G1 + 1/2 G2) and type of microbial additive (TMA; G1 vs. G2). Results are described in sequence as CON, G1, and G2. Intake of DM (22.2 vs. 22.4 vs. 22.4 kg/d), BW (685 vs. 685 vs. 685 kg) and the daily BW change (0.40 vs. 0.39 vs. 0.39 kg/d) did not differ among treatments; however, feeding MA tended to increase BCS (3.28 vs. 3.33 vs. 3.36). Supplementing MA increased yields of milk (39.9 vs. 41.3 vs. 41.5 kg/d), ECM (37.9 vs. 39.3 vs. 39.9 kg/d), fat (1.31 vs. 1.37 vs. 1.40 kg/d), TS (4.59 vs. 4.75 vs. 4.79 kg/d), and ECM per kg of DMI (1.72 vs. 1.76 vs. 1.80 kg/kg). Furthermore, cows fed MA increased yields of preformed fatty acids in milk fat (>16C; 435 vs. 463 vs. 488 g/d), particularly UFA (367 vs. 387 vs. 410 g/d), such as linoleic (C18:2 cis-9,cis-12; 30.9 vs. 33.5 vs. 35.4 g/d) and α-linolenic acids (C18:3 cis-9,cis-12,cis-15; 2.46 vs. 2.68 vs. 2.82 g/d) on d 60 and 62 in the experiment. Collectively, supplementing G1 and G2 improved productive performance of cows with no differences between the 2 MA.

Effects of supplementing rumen-protected arginine on performance of transition cows.

An experiment was conducted to determine the effects of supplementing rumen-protected arginine (RPA) on productive performance in dairy cows. One-hundred and 2 cows were blocked by parity and then by energy-corrected milk (ECM) yield. Within block, cows were randomly assigned to control (CON) that received 200 g/d of a mixture of hydrogenated soybean oil and heat-treated soybean meal to supply 30 g of metabolizable protein (MP), or 200 g/d of a product containing 30 g of metabolizable arginine (RPA), which increased the dietary arginine from 5.7 to 7.5% of the MP from 250 d of gestation to 21 d postpartum. After 21 d postpartum, cows were fed the same diet and data were collected until 84 d postpartum. Cows fed RPA produced an additional 2.5 kg of colostrum (5.3 vs. 7.8 ± 1.0 kg) and 220 g more immunoglobulin G (526 vs. 746 ± 93 g) than CON cows. Supplementing RPA increased the yields of milk (32.8 vs. 34.9 ± 1.0 kg/d), ECM (37.8 vs. 40.9 ± 1.2 kg/d), and milk total solids (4.48 vs. 4.86 ± 0.14 kg/d) in the first 21 DIM. The benefits of RPA extended beyond the period of supplementation, with a 6.4% increase in yield of ECM per kg of dry matter consumed in all cows (1.88 vs. 2.00 ± 0.05 kg/kg) and an increase in ECM yield, but only in parous cows (44.2 vs. 48.5 ± 1.5 kg/d). Feeding RPA increased the concentrations of urea N in plasma pre- (12.5 vs. 13.9 ± 0.4 mg/dL) and postpartum (11.6 vs. 13.2 ± 0.4 mg/dL), and in milk during the first 21 d postpartum (11.0 vs. 12.0 ± 0.3 mg/dL). Treatment did not affect the concentrations of AA in plasma prepartum, but feeding RPA tended to increase citrulline (72.5 vs. 77.5 ± 2.7 µM), whereas RPA either tended to decrease isoleucine (129.5 vs. 120.9 ± 5.7 µM) or decreased the concentrations of leucine (181.3 vs. 170.2 ± 6.4 µM) and valine (293.2 vs. 276.7 ± 10.4 µM) postpartum. Feeding RPA increased the relative expression of transcripts involved in AA transport (SLC38A4), urea cycle (ARG1), and gluconeogenesis (PC, PEPCK, and G6PC) in hepatic tissue. Feeding diets to supply additional arginine as RPA during the transition period benefited productive performance in dairy cows that extended beyond the period of supplementation despite minor changes in plasma AA concentrations.

Production, physiological response, and calcium and magnesium balance of lactating Holstein cows fed different sources of supplemental magnesium with or without ruminal buffer.

The objective of this study was to evaluate the effects of dietary replacement of magnesium oxide (MgO) with calcium-magnesium hydroxide [CaMg(OH)2] and its interaction with ruminal buffer (sodium sesquicarbonate) supplementation on production, Ca and Mg balance, and overall physiological response of mid-lactation Holstein dairy cows. Sixty cows averaging 40.5 ± 7.0 kg of milk/d were used. Treatments were assigned following a 2 × 2 factorial arrangement: (1) MgO, (2) MgO + buffer, (3) CaMg(OH)2, or (4) CaMg(OH)2 + buffer. Diets were formulated to have 16.5% of crude protein, 1.82 Mcal/kg of net energy for lactation, 0.67% Ca, 0.39% P, and 0.25% Mg, all on a dry matter (DM) basis. Treatments were individually top dressed. Milk production, composition, and DM intake were evaluated. A subsample of 20 cows were randomly selected for the evaluation of Ca and Mg balance, blood gases, and electrolytes. Ruminal fluid was also collected for evaluation of pH and Ca and Mg solubility. Effects of Mg source, buffer, and the interaction Mg source × buffer were analyzed through orthogonal contrasts. An interaction of Mg source × buffer was found for DM intake and feed efficiency, in which cows fed CaMg(OH)2 had a similar feed efficiency regardless of ruminal buffer inclusion; however, when cows were fed MgO, the inclusion of buffer reduced feed efficiency. No effects on body weight and milk yield were observed. Buffer addition tended to increase the concentrations of fat, protein, and solids-not-fat, without affecting the yields of these milk components. Magnesium source and buffer did not affect ruminal fluid, blood, urine, or fecal pH; however, buffer supplementation increased urinary pH. Treatment with CaMg(OH)2 increased blood concentration of HCO3-, total CO2, and base excess compared with cows fed MgO. No differences were observed in the ruminal solubility of Ca and Mg or on milk or urinary Ca and Mg excretion. Greater plasma Mg concentration was observed for animals fed MgO compared with cows fed CaMg(OH)2; however, both sources were above the threshold recommended in the literature for dairy cows. Also, a reduction in fecal Mg excretion was observed in animals fed CaMg(OH)2. In summary, we provide evidence that CaMg(OH)2 could replace MgO without affecting performance, overall physiological response, or Ca and Mg balance of mid-lactating dairy Holstein cows.

Induced endometritis in early lactation compromises production and reproduction in dairy cows.

Objectives of this experiment were to study the effect of infusing utero-pathogenic bacteria to induce endometrial inflammation on productive performance in early lactation and subsequent reproduction. Although endometritis is associated with perturbed reproduction, numerous factors may contribute to the observed association. It was hypothesized that induced endometrial inflammation, resulting in localized and systemic inflammatory responses, compromises production and reproduction. Holstein cows without clinical disease and with less than 18% polymorphonuclear leukocytes (PMN) in endometrial cytology on d 31 ± 3 postpartum had their estrous cycle synchronized. Cows were blocked by parity and genomic breeding value for cow conception rate and, within block, assigned randomly to remain as untreated controls (CON; n = 37) or to receive an intrauterine infusion of 5.19 × 108 cfu Escherichia coli and 4.34 × 108 cfu Trueperella pyogenes during the luteal phase to induce endometrial inflammation (INF; n = 48). Endometrial cytology was taken on d 2 and 7 after treatment to evaluate the proportion of PMN. Rectal temperature, dry matter intake, and yields of milk and components were measured in the first 7 d after treatment. Blood serum was analyzed for concentration of haptoglobin. Leukocytes were isolated from blood on d 2 and 7 after treatment and on d 19 after artificial insemination (AI) and mRNA was quantified for a select group of genes. Cows received AI and reproduction was followed for 300 d postpartum. Bacterial infusion induced endometrial inflammation with increased proportions of PMN in the endometrial cytology on d 2 (4.4 ± 0.7 vs. 26.3 ± 2.8%) and 7 (10.9 ± 1.7 vs. 17.4 ± 2.1%) after treatment, resulting in increased mean prevalence of subclinical endometritis (>10% PMN; 23.3 ± 6.3 vs. 80.9 ± 5.1%). Rectal temperature did not differ between CON and INF, but the concentration of haptoglobin in serum tended to increase in INF compared with CON (113 ± 14 vs. 150 ± 16 µg/mL). Induced endometrial inflammation reduced yields of milk (44.9 ± 0.8 vs. 41.6 ± 0.8 kg/d), protein (1.19 ± 0.03 vs. 1.12 ± 0.03 kg/d), and lactose (2.17 ± 0.04 vs. 2.03 ± 0.04 kg/d) and tended to reduce dry matter intake (20.7 ± 0.5 vs. 19.4 ± 0.6 kg/d) in the first 7 d after treatment. Indeed, the reduction in milk yield lasted 4 wk. However, treatment did not affect yields of energy-corrected milk or fat because treatment with INF increased the concentration of fat in milk (3.54 ± 0.10 vs. 3.84 ± 0.10%). Induced endometrial inflammation reduced pregnancy per AI at all inseminations (33.4 ± 5.1 vs. 21.6 ± 3.7%) and the hazard of pregnancy (0.61; 95% CI = 0.36-1.04), which extended the median days open by 24 d. Blood leukocytes from INF cows had increased mRNA expression of the pro-inflammatory gene IL1B on d 2 and 7 after treatment, but reduced expression of the IFN-stimulated genes ISG15 and MX2 on d 19 after AI. Induced endometrial inflammation depressed production and caused long-term negative effects on reproduction in lactating dairy cows.

Oral paracoccidioidomycosis: a retrospective study of 95 cases from a single center and literature review.

BACKGROUND: The ecoepidemiological panorama of paracoccidioidomycosis (PCM) is dynamic and still ongoing in Brazil. In particular, data about the oral lesions of PCM are barely explored. The aim of this study was to report the clinicopathological features of individuals diagnosed with oral PCM lesions at an oral and maxillofacial pathology service in Rio de Janeiro, Brazil, in the light of a literature review. MATERIAL AND METHODS: A retrospective study was conducted on oral biopsies obtained from 1958 to 2021. Additionally, electronic searches were conducted in PubMed, Embase, Scopus, Web of Science, Latin American and Caribbean Center on Health Sciences Information, and Brazilian Library of Dentistry to gather information from large case series of oral PCM. RESULTS: Ninety-five cases of oral PCM were surveyed. The manifestations were more frequent among males (n=86/90.5%), middle-aged/older adults (n=54/58.7%), and white individuals (n=40/51.9%). The most commonly affected sites were the gingiva/alveolar ridge (n=40/23.4%) and lip/labial commissure (n=33/19.3%); however, one (n=40/42.1%) or multiple sites (n=55/57.9%) could also be affected. In 90 (94.7%) patients, "mulberry-like" ulcerations/moriform appearance were observed. Data from 21 studies (1,333 cases), mostly Brazilian (90.5%), revealed that men (92.4%; male/female: 11.8:1) and individuals in the fifth and sixth decades of life were the most affected (range: 7-89 years), with the gingiva/alveolar ridge, palate, and lips/labial commissure being the sites most frequently affected. CONCLUSIONS: The features of oral PCM lesions are similar to those reported in previous studies from Latin America. Clinicians should be aware of the oral manifestations of PCM, with emphasis on the clinicodemographic aspects and differential diagnoses, especially considering the phenomenon of the emergence of reported cases in rural and/or urban areas of Brazil.

The action of curcumin against damage resulting from cerebral stroke: A systematic review.

Stroke is the second leading cause of morbidity and mortality globally. Treatments for stroke are limited, and preventive treatments are scarce. Curcumin (CUR) has several biological effects, as described in the literature, which highlight its antioxidant and neuroprotective effects. Therefore, this qualitative systematic review aimed to investigate the effects of CUR on damage caused by stroke in rodent models. A systematic search was performed on three databases PubMed, Scopus, and Web of Science. In addition, the risk-of-bias and quality of the studies were assessed using SYRCLE and Collaborative Approach for Meta-Analysis and Review of Animal Data from Experimental Studies, respectively. The selection, inclusion, and exclusion criteria were established by the authors. At the end of our systematic search of the three databases, we found a total of 728 articles. After excluding duplicates and triplicates and reading the abstracts, keywords, and full texts, 53 articles were finally included in this systematic review. CUR exerts several beneficial effects against the damage caused by both ischemic and hemorrhagic stroke, via different pathways. However, because of its low bioavailability, Free-form CUR only exerted significant effects when it was administered at high concentrations. In contrast, when CUR was administered using nanostructured systems, positive responses were observed even at low concentrations. The mechanisms of action of CUR, free or in nanostructure, are extremely important for the recovery of injured brain tissue after a stroke; CUR has neuroprotective, antioxidant, anti-inflammatory, and anti-apoptotic effects and helps to maintain the integrity of the blood-brain barrier. Finally, we concluded that CUR presents an extremely important and significant response profile against the damage caused by stroke, making it a possible therapeutic candidate for individuals affected by this disease.

Assessing feed efficiency in early and mid lactation and its associations with performance and health in Holstein cows.

Objectives were to evaluate the associations between residual dry matter (DM) intake (RFI) and residual N intake (RNI) in early lactation, from 1 to 5 wk postpartum, and in mid lactation, from 9 to 15 wk postpartum, and assess production performance and risk of diseases in cows according to RFI in mid lactation. Data from 4 experiments including 399 Holsteins cows were used in this study. Intakes of DM and N, yields of milk components, body weight, and body condition were evaluated daily or weekly for the first 105 d postpartum. Milk yield by 305 d postpartum was also measured. Incidence of disease was evaluated for the first 90 d postpartum and survival up to 300 d postpartum. Residual DM and N intake were calculated in early and mid lactation as the observed minus the predicted values, which were based on linear models that accounted for major energy or N sinks, including daily milk energy or N output, metabolic body weight, and daily body energy or N changes, and adjusting for parity, season of calving, and treatment within experiment. Cows were ranked by RFI and RNI in mid lactation and categorized into quartiles (Q1 = smallest RFI, to Q4 = largest RFI). Increasing efficiency in mid lactation resulted in linear decreases in RFI (depicted from Q1 to Q4; -0.93, -0.05, -0.04, and 0.98 kg/d), DMI (16.0, 16.9, 17.3, and 18.4 kg/d), net energy for lactation (NEL) intake (26.8, 28.4, 29.0, and 30.8 Mcal/d), and NEL balance (-9.0, -8.1, -8.2, and -5.5 Mcal/d) during early lactation, but no differences were observed in body NEL or N changes or yield of energy-corrected milk in the first 5 wk of lactation. Residual DM intake in mid lactation was associated with RFI (Pearson r = 0.43, and Spearman ρ = 0.32) and RNI (r = 0.44, ρ = 0.36) in early lactation, and with RNI in mid lactation (r = 0.91, ρ = 0.84). Similarly, RNI in mid lactation was associated with RNI in early lactation (r = 0.42, ρ = 0.35). During the first 15 wk postpartum, more efficient cows in mid lactation consumed 3.5 kg/d less DM (Q1 = 19.3 vs. Q4 = 22.8 kg/d) and were more N efficient (Q1 = 31.6 vs. Q4 = 25.8%), at the same time that yields of milk (Q1 = 39.0 vs. Q4 = 39.4 kg/d), energy-corrected milk (Q1 = 38.6 vs. Q4 = 39.3 kg/d), and milk components did not differ compared with the quartile of least efficient cows. Furthermore, RFI in mid lactation was not associated with 305-d milk yield, incidence of diseases in the first 90 d postpartum, or survival by 300 d postpartum. Collectively, rankings of RFI and RNI are associated and repeatable across lactation stages. The most feed-efficient cows were also more N efficient in early and mid lactation. Phenotypic selection of RFI based on measurements in mid lactation is associated with improved efficiency without affecting production or health in dairy cows.

Effects of maternal level of dietary cation-anion difference fed to prepartum nulliparous cows on offspring acid-base balance, metabolism, and growth.

The objectives were to determine the effects of dietary cation-anion difference (DCAD) fed to pregnant cows during the last 22 d of gestation on offspring acid-base balance, metabolism, growth, and health preweaning. A total of 132 nulliparous Holstein cows were enrolled at 250 (248 to 253) d of gestation in a randomized block design. Cows were blocked by genomic merit of energy-corrected milk yield and assigned randomly to diets varying in DCAD: +200 (P200, n = 43), -50 (N50, n = 45), or -150 (N150, n = 44) mEq/kg of dry matter (DM). Newborn calves (15 males and 28 females in P200, 22 males and 23 females in N50, and 18 males and 26 females in N150) were followed for the first 7 or 56 d of age if males or females, respectively. Measures of acid-base balance and concentrations of minerals in blood were measured in all calves on d 0 before colostrum feeding, and on d 1, 3, and 7. Each calf was fed 3.78 L of colostrum from the respective treatment, and apparent efficiency of IgG absorption was determined. All calves were weighed at birth, and females were weighed again at 21, 42, and 56 d of age. Concentrations in serum of total calcium (tCa), total magnesium (tMg), and total phosphorus (tP) were measured up to 56 d of age; intakes of milk and starter grain DM were measured daily from 21 to 56 d of age; and incidence of disease was recorded for the first 56 d of age in females. Treatment did not affect acid-base balance measured in all calves. Calves were born with metabolic and respiratory acidosis, which reversed by 1 d of age. In the first 24 h after birth, blood pH increased from 7.215 to 7.421 and bicarbonate from 26.2 to 31.7 mM, whereas partial pressure of CO2 decreased from 64.1 to 48.7 mm of Hg in all treatments. Maternal DCAD did not affect colostrum IgG content fed to calves (P200 = 95.0 vs. N50 = 91.0 vs. N150 = 97.1 ± 4.1 g/L) or apparent efficiency of IgG absorption (P200 = 33.1 vs. N50 = 33.1 vs. N150 = 34.2 ± 1.9%). Males were born heavier than females, but maternal DCAD did not affect birth weight of all calves (P200 = 37.7 vs. N50 = 37.3 vs. N150 = 37.8 ± 0.7 kg) or daily weight gain in females in the first 56 d of life (P200 = 0.80 vs. N50 = 0.81 vs. N150 = 0.77 ± 0.03 kg/d). Treatment did not affect intake of milk (P200 = 1.11 vs. N50 = 1.04 vs. N150 = 1.19 ± 0.06 kg/d) or starter grain DM (P200 = 0.27 vs. N50 = 0.27 vs. N150 = 0.21 ± 0.06 kg/d), or measures of feed efficiency. Treatment did not affect concentrations of minerals in serum, morbidity, or age at morbidity. Manipulating the DCAD of pregnant nulliparous dams during late gestation did not affect offspring performance in the first 2 mo of age.

Prepartum level of dietary cation-anion difference fed to nulliparous cows: Acid-base balance, mineral metabolism, and health responses.

Objectives were to determine the effects of 3 different levels of dietary cation-anion difference (DCAD) fed during the last 22 d of gestation to pregnant nulliparous cows on pre- and postpartum acid-base balance, mineral metabolism, and health responses. In all, 132 pregnant nulliparous Holstein cows were enrolled at 250 (248-253) d of gestation, blocked by genomic merit of energy-corrected milk yield, and assigned randomly to diets varying in DCAD: +200 (P200, n = 43), -50 (N50, n = 45), or -150 (N150, n = 44) mEq/kg of dry matter. Dietary treatments were fed until calving, after which cows received the same lactation diet for the first 100 d postpartum. Urine and blood were sampled throughout the prepartum period and in the first weeks postpartum, and urine was assessed for pH, whereas blood was analyzed for gases, measures of acid-base balance, minerals, and metabolites. Calcium (Ca) and magnesium (Mg) retention and phosphorus (P) digestibility were evaluated in the last week of gestation and first week of lactation. Incidence of diseases was evaluated for the first 100 d postpartum. Data are presented in sequence as P200, N50, N150 (LSM ± SEM). Reducing the DCAD reduced urine (8.17 vs. 6.50 vs. 5.51 ± 0.11) and blood pH (7.442 vs. 7.431 vs. 7.410 ± 0.004) and induced a state of compensated metabolic acidosis with a reduction in blood HCO3- (28.4 vs. 26.7 vs. 24.9 ± 0.3 mM) and partial pressure of CO2 (41.8 vs. 40.1 vs. 39.1 ± 0.4 mmHg) prepartum. Reducing the DCAD linearly increased blood ionized Ca (iCa; 1.224 vs. 1.243 vs. 1.259 ± 0.008 mM) and serum total Ca (tCa; 2.50 vs. 2.53 vs. 2.56 ± 0.02 mM) prepartum, blood iCa on the day of calving, and serum Mg in the first days postpartum. Reducing the DCAD linearly increased the apparent absorption of Ca (12.9 vs. 19.0 vs. 20.9 ± 1.4 g/d) and Mg (7.0 vs. 9.9 vs. 10.4 ± 1.4 g/d) prepartum, but apparent retention of both Ca (13.9 g/d) and Mg (3.4 g/d) did not differ with treatment. Treatment did not affect digestibility of P pre- or postpartum or retention of Ca or Mg postpartum. Treatment did not affect the incidence or prevalence of subclinical hypocalcemia, hepatic composition, or the prevalence of fatty liver. Reducing the DCAD had a quadratic effect on incidence of fever (46.5 vs. 17.6 vs. 33.9 ± 7.0%), uterine diseases (36.3 vs. 25.6 vs. 46.0 ± 7.3%), and morbidity (41.4 vs. 28.1 vs. 55.6 ± 7.3%). Feeding a diet with -50 mEq/kg of dry matter promoted moderate changes in acid-base balance, altered mineral metabolism, and benefited health of nulliparous cows; however, further reducing the DCAD to -150 mEq/kg negated the benefits to health.

Effect of source and amount of vitamin D on function and mRNA expression in immune cells in dairy cows.

Objectives were to determine the effect of supplementing 2 sources of vitamin D, cholecalciferol (CH) or calcidiol (CA), at 1 (1mg) or 3 mg/d (3mg) prepartum on concentrations of vitamin D metabolites in plasma, measures of innate immune function, and leukocyte mRNA expression. Parous Holstein cows (n = 99) were assigned to a daily treatment administered as top-dress containing either 1 or 3 mg of CH (CH1 or CH3) or of CA (CA1 or CA3) from 250 d of gestation until calving. Plasma concentrations of vitamin D, immune cell population in blood, cell adhesion markers, and granulocyte phagocytosis and oxidative burst were evaluated pre- and postpartum. The mRNA expression in leukocytes was determined at 270 d of gestation and 3 d postpartum for genes involved in cell migration, pathogen recognition receptors, cell signaling, cytokines, antimicrobial mechanisms, oxidative burst, and Ca and vitamin D metabolism. Concentrations of vitamin D3 increased in cows fed CH, whereas those of 25-hydroxyvitamin D3 increased in cows fed CA. Percentage of granulocytes from total leukocytes differed with amount of vitamin D pre- (1mg = 24.5 vs. 3mg = 37.9%) and postpartum (1mg = 22.0 vs. 3mg = 31.0%), thus shifting mononuclear cells in the opposite direction pre- (1mg = 75.5 vs. 3mg = 62.1%) and postpartum (1mg = 78.0 vs. 3mg = 69.0%). Granulocytes displaying phagocytosis (1mg = 69.0 vs. 3mg = 62.9%) and intensity of phagocytosis prepartum (1mg = 7.46 vs. 3mg = 7.28) tended to be less in cows fed 3mg compared with 1mg. During prepartum, CA increased mRNA expression of genes related to cell adhesion and migration (CD44, ICAM1, ITGAL, ITGB1, LGALS8, SELL), pathogen recognition receptor (NOD2, TLR2, TLR6), cell signaling (FOS, JUN, NFKB2), cytokine signaling (IL1B, IL1R1, IL1RN), antimicrobial mechanisms (CTSB, LYZ), and Ca metabolism (ATP2B1, STIM1, TRPV5) compared with CH. Similarly, postpartum, CA increased mRNA expression of genes related to cell adhesion and migration (CXCR2, SELL, TLN1), cell signaling (AKT2), cytokines (CCL2, IL1R1, ILRN), antimicrobial mechanisms (DEFB3), oxidative burst (RAC2), and calcium metabolism (CALM3) compared with CH. Feeding additional vitamin D in the last 3 wk of gestation changed the profile of blood leukocytes and attenuated granulocyte phagocytosis during the transition period, whereas supplementing CA prepartum increased mRNA expression of genes involved in immune cell function, including genes related to pathogen recognition and antimicrobial effects of leukocytes.

Effect of duration of exposure to diets differing in dietary cation-anion difference on Ca metabolism after a parathyroid hormone challenge in dairy cows.

Objectives of the experiment were to determine the length of exposure to an acidogenic diet that would elicit changes in acid-base balance, mineral digestion, and response to parathyroid hormone (PTH)-induced changes in blood Ca and vitamin D3 in prepartum dairy cows. Nonlactating parous Holstein cows (n = 20) at 242 d of gestation were blocked by lactation (1 or >1) and pretreatment dry matter (DM) intake and, within block, they were randomly assigned to a diet with a dietary cation-anion difference (DCAD) of +200 mEq/kg of DM (DCAD +200) or an acidogenic diet with -150 mEq/kg of DM (DCAD -150). Water and DM intake were measured and blood was sampled daily. Urine was sampled every 3 h for 36 h, and then daily. During PTH challenges on d 3, 8, and 13, cows received i.v. PTH 1-34 fragment at 0.05 µg/kg of body weight every 20 min for 9 h to mimic the pulsatile release of endogenous PTH. Blood was sampled at 0 h, and hourly thereafter until 10 h, and at 12, 18, 24, 36, and 48 h relative to each challenge. Acid-base measures and concentrations of ionized Ca (iCa) in whole blood, and total Ca, Mg, P, and vitamin D metabolites in plasma were evaluated. On d 2 and 7, Ca, Mg, and P balances were evaluated. Cows fed DCAD -150 had smaller blood pH (7.431 vs. 7.389) and HCO3- (27.4 vs. 22.8 mM) compared with DCAD +200, and metabolic acidosis in DCAD -150 was observed 24 h after dietary treatments started. Concentrations of iCa begin to increase 24 h after feeding the acidogenic diet, and it was greater in DCAD -150 compared with DCAD +200 by 3 d in the experiment (1.23 vs. 1.26 mM). During the PTH challenges, cows fed DCAD -150 had greater concentration of iCa and area under the curve for iCa than those fed DCAD +200 (48.2 vs. 50.7 mmol/L × hour), and there was no interaction between treatment and challenge day. Concentration of 1,25-dihydroxyvitamin D3 in plasma did not differ during the PTH challenge, but change in 1,25-dihydroxyvitamin D3 relative to h 0 of the challenge was smaller in cows fed DCAD -150 than cows fed DCAD +200 (44.1 vs. 32.9 pg/mL). Urinary loss of Ca was greater in cows fed DCAD -150 compared with DCAD +200 (1.8 vs. 10.8 g/d); however, because digestibility of Ca increased in cows fed DCAD -150 (19.7 vs. 36.6%), the amount of Ca retained did not differ between treatments. Diet-induced metabolic acidosis was observed by 24 h after dietary treatment started, resulting in increases in concentration of iCa in blood observed between 1 and 3 d. Collectively, present results indicate that tissue responsiveness to PTH and changes in blood concentrations of iCa and digestibility of Ca are elicited within 3 d of exposure to an acidogenic diet. The increased apparent digestibility of Ca compensated for the increased urinary loss of Ca resulting in similar Ca retention.

Prepartum level of dietary cation-anion difference fed to nulliparous cows: Lactation and reproductive responses.

Objectives were to determine the effects of 3 levels of dietary cation-anion difference (DCAD) fed prepartum to nulliparous cows on productive and reproductive performance. We enrolled 132 pregnant nulliparous Holstein cows at 250 (248-253) d of gestation in a randomized block design. Cows were blocked by genomic merit of energy-corrected milk yield and assigned randomly to diets varying in DCAD, +200 (P200; n = 43), -50 (N50; n = 45), or -150 (N150; n = 44) mEq/kg of dry matter (DM). Dietary treatments were fed during the last 22 d of gestation and, after calving, postpartum cows received the same lactation diet. Productive performance was evaluated for the first 14 wk of lactation, and reproduction was assessed until 305 d postpartum. Intake of DM prepartum decreased linearly (results presented in sequence as least squares means ± standard error of the mean, P200 vs. N50 vs. N150) with a reduction in DCAD (9.0 vs. 8.9 vs. 8.4 ± 0.1 kg/d), which resulted in linear decreases in net energy balance (0.34 vs. 0.20 vs. -0.36 ± 0.20 Mcal/d), body weight change (1.1 vs. 0.8 vs. 0.3 ± 0.1 kg/d), and mean body weight (652 vs. 649 vs. 643 ± 2 kg) prepartum. Treatment did not affect yield of colostrum (6.3 vs. 5.8 vs. 5.1 ± 0.6 kg) or the contents or yields of fat, protein, lactose, IgG, Ca, or Mg in colostrum. Intake of DM (19.4 vs. 19.2 vs. 19.0 ± 0.2 kg/d), yields of milk (36.6 vs. 36.7 vs. 35.8 ± 0.6 kg/d) or energy-corrected milk (36.7 vs. 36.3 vs. 35.9 ± 0.5 kg/d), feed efficiency (1.93 vs. 1.92 vs. 1.93 ± 0.03 kg of energy-corrected milk per kilogram of DM intake), and content and yield of milk components did not differ among treatments during the first 14 wk of lactation. Prepartum DCAD did not affect the cumulative milk yield by 305 d of lactation (9,653 vs. 10,005 vs. 9,918 ± 196 kg). Of the 132 cows, 40 P200, 45 N50, and 43 N150 received at least 1 artificial insemination (AI), and treatment did not affect pregnancy per AI at first (32.5 vs. 35.6 vs. 37.2%) or all AI (30.6 vs. 33.9 vs. 40.2%), although reducing the DCAD increased the proportion of cows pregnant by 305 d postpartum (76.7 vs. 88.9 vs. 93.2%) without altering the rate of pregnancy. Collectively, manipulating the DCAD of prepartum diets, from +200 to -150 mEq/kg of DM, fed to late gestation nulliparous cows did not affect subsequent lactation productive performance, but may have provided some benefit to reproduction, which warrants further confirmation.

Adequacy of planctomycetes as supplementary food source for Daphnia magna.

The nutritional quality of daphnids diet can influence their growth, reproduction and survival. In aquatic ecosystems, bacteria can contribute significantly to Daphnia diet by supporting, for instances, their high needs for phosphorus. The laboratory feeding of the model organisms Daphnia spp. is algal based, but should be improved to allow their better performance. The aim of this study was to evaluate the potential of two planctomycetes, Gemmata obscuriglobus and Rhodopirellula rubra, from exponential and stationary growth phases as alternative or supplementary food source for Daphnia magna. The actinobacterium Arthrobacter sp. was used for comparison. The feeding with only bacteria showed the inefficacy of both planctomycetes and actinobacteria as the only food source. However, when used in supplement to Raphidocelis subcapitata, a decrease in the age of first reproduction, a significant increase in reproductive output, in somatic growth and in rate of population increase was found for the highest cell densities of bacteria tested. The typical pink coloration of these bacteria present in daphnids body and eggs confirmed bacterial absorption and metabolization of their pigment. Planctomycetes yielded better results than the actinobacteria Arthrobacter but G. obscuriglobus that possesses sterols did not induce a better performance comparatively to R. rubra. No relation could be established between the feeding treatments that allowed improvement of Daphnia performance and the different kind of Daphnia' Fatty Acid Methyl Esters. The use of sonication to separate planctomycetal cells before feeding the daphnids proved to be efficient. We confirmed that R. subcapitata supplemented by bacteria allows a better growth performance of D. magna.

New remarkable sexually dimorphic miniature species of Hyphessobrycon (Characiformes: Characidae) from the upper Rio Tapajós basin.

A new miniature species of Hyphessobrycon is described from an affluent of the Rio Papagaio, tributary of the Rio Juruena, upper Rio Tapajós basin, Mato Grosso State, Brazil. The new species can be distinguished from its congeners by having a remarkable secondary sexual dimorphism in its live colouration (males are red and females yellow), well-defined and relatively narrow dark midlateral stripe extending from tip of snout to tip of middle caudal-fin rays, absence of humeral blotch, 15-18 branched anal-fin rays and five or six branched pelvic-fin rays. The sexually dimorphic colouration of the new species is briefly discussed regarding its temporal variation.

Comparative development in Moenkhausia pittieri and Paracheirodon innesi (Ostariophysi: Characiformes) with comments on heterochrony and miniaturization in the Characidae.

Developmental heterochronies between the small-sized Moenkhausia pittieri and the miniature Paracheirodon innesi were determined by describing and comparing external morphological development in both species. Despite being classified as miniature, P. innesi was larger and more developed in the flexion and post-flexion larval stages than M. pittieri. Broader patterns within the Characidae suggest that body size reduction in P. innesi is tied to accelerated development and higher growth rate along with early maturation and precocious cessation of growth, which are characteristic of miniature species. Comments on adipose-fin loss in Characidae as a consequence of developmental truncation are included.

The influence of espresso coffee on neurocognitive function in HIV-infected patients.

The aim of our study was to evaluate the impact of coffee intake on cognitive function in persons living with HIV (PLWH). 130 PLWH with CD4 > 200 cells/mm(3), undetectable viral load, treated with HAART were included. A structured interview was applied and relevant clinical and laboratory data were assessed, including coffee intake. For neuropsychological assessment, the HIV Neurobehavioral Research Center Battery was chosen. Univariate nonparametric statistics and multivariate regression model were used. A significant association between espresso coffee use and a better cognitive function was verified in five of the eight psychometric measurements. In the multivariate analysis, after variable adjustment, linear regression analysis showed that coffee intake was a positive predictor for attention/working memory, executive functions and Global Deficit Score. Although the mechanisms behind the influence of caffeine on cognitive functioning are controversial, regular espresso coffee intake may have favourable effects on cognitive deterioration caused by HIV.

A name for the 'blueberry tetra', an aquarium trade popular species of Hyphessobrycon Durbin (Characiformes, Characidae), with comments on fish species descriptions lacking accurate type locality.

A new species of Hyphessobrycon is described from a tributary of the upper Rio Tapajós, Amazon basin, Mato Grosso, Brazil. Its exuberant colour in life, with blue to purple body and red fins, is appreciated in the aquarium trade. Characters to diagnose the new species from all congeners are the presence of a single humeral blotch, absence of a distinct caudal-peduncle blotch, absence of a well-defined dark mid-lateral stripe on body, the presence of 16-18 branched anal-fin rays, nine branched dorsal-fin rays and six branched pelvic-fin rays. A brief comment on fish species descriptions solely based on aquarium material and its consequence for conservation policies is provided.

Grazing behaviour of a non-herbivorous characin: revisiting plasticity.

Feeding behaviour and diet of Bryconamericus microcephalus differed between canopy conditions. At the open canopy site, a behavioural modification, grazing on algae, was observed. This was also reflected in gut content analysis and suggests behavioural plasticity in response to resource availability.

Structural characterization of the internal transcribed spacer 2 (ITS2) of the ribosomal DNA (rDNA) cluster in Calyptratae (Diptera: Schizophora) and its implications for molecular phylogenetic analyses.

The internal transcribed spacer 2 (ITS2) of the eukaryotic ribosomal DNA (rDNA) cluster plays an essential role in processing of the ribosomal RNA, which is primarily accomplished by the secondary structures acquired by the molecule after transcription. Two possible structural conformation models have been proposed for the ITS2 region, the "ring model" and the "hairpin model," and the former has been widely used in many molecular phylogenetic analyses incorporating structural information available to date. To evaluate the validity of this model, in vitro transcribed ITS2 molecules from species representing the three superfamilies of the Calyptratae clade (Diptera: Schizophora), namely Cochliomyia hominivorax, Musca domestica, and Glossina morsitans, were submitted to enzymatic digestion with single- and double-stranded specific nucleases (RNases I, A, T1, and V1). The resulting fragments were analyzed by capillary electrophoresis and digestion sites were mapped in the secondary structure models which were obtained by in silico prediction with further refinement by homology comparisons. The pattern of RNA fragments generated by these RNases show a high degree of correlation to most of the predicted helix-loop regions and structural motifs. Discrepancies to the models can be explained by alternative structural conformation dynamics (in M. domestica and G. morsitans) and by higher-order factors (such as tertiary interactions) that may stabilize thermodynamically unfavored structures (in C. hominivorax).