Feedlot performance and rumen morphometrics of Nellore cattle adapted to high-concentrate diets over periods of 6, 9, 14 and 21 days.

The energy content of finishing diets offered to feedlot cattle may vary across countries. We assumed that the lower is the energy content of the finishing diet, the shorter can be the adaptation period to high-concentrate diets without negatively impacting rumen health while still improving feedlot performance. This study was designed to determine the effects of adaptation periods of 6, 9, 14 and 21 days on feedlot performance, feeding behaviour, blood gas profile, carcass characteristics and rumen morphometrics of Nellore cattle. The experiment was designed as a completely randomised block, replicated 6 times, in which 96 20-month-old yearling Nellore bulls (391.1 ± 30.9 kg) were fed in 24 pens (4 animals/pen) according to the adaptation period adopted: 6, 9, 14 or 21 days. The adaptation diets contained 70%, 75% and 80.5% concentrate, and the finishing diet contained 86% concentrate. After adaptation, one animal per pen was slaughtered (n = 24) for rumen morphometric evaluations and the remaining 72 animals were harvested after 88 days on feed. Orthogonal contrasts were used to assess linear, quadratic and cubic relationships between days of adaptation and the dependent variable. Overall, as days of adaptation increased, final BW (P = 0.06), average daily gain (ADG) (P = 0.07), hot carcass weight (P = 0.04) and gain to feed ratio (G : F) (P = 0.07) were affected quadratically, in which yearling bulls adapted by 14 days presented greater final BW, ADG, hot carcass weight and improved G : F. No significant (P > 0.10) days of adaptation effect was observed for any of feeding behaviour variables. As days of adaptation increased, the absorptive surface area of the rumen was affected cubically, where yearling bulls adapted by 14 days presented greater absorptive surface area (P = 0.03). Thus, Nellore yearling bulls should be adapted by 14 days because it led to improved feedlot performance and greater development of rumen epithelium without increasing rumenitis scores.

Short-term testicular warming under anesthesia causes similar increases in testicular blood flow in Bos taurus versus Bos indicus bulls, but no apparent hypoxia.

Bull testes must be 4-5 °C below body temperature, with testicular warming more likely to cause poor-quality sperm in Bos taurus (European/British) versus Bos indicus (Indian/zebu) bulls. Despite a long-standing dogma that testicular hyperthermia causes hypoxia, we reported that increasing testicular temperature in bulls and rams enhanced testicular blood flow and O2 delivery/uptake, without hypoxia. Our objective was to determine effects of short-term testicular hyperthermia on testicular blood flow, O2 delivery and uptake and evidence of testicular hypoxia in pubertal Angus (B. taurus) and Nelore (B. indicus) bulls (nine per breed) under isoflurane anesthesia. As testes were warmed from 34 to 40 °C, there were increases (P < 0.0001, but no breed effects) in testicular blood flow (mean ± SEM, 9.59 ± 0.10 vs 17.67 ± 0.29 mL/min/100 g, respectively), O2 delivery (1.79 ± 0.06 vs 3.44 ± 0.11 mL O2/min/100 g) and O2 consumption (0.69 ± 0.07 vs 1.25 ± 0.54 mL O2/min/100 g), but no indications of testicular hypoxia. Hypotheses that: 1) both breeds increase testicular blood flow in response to testicular warming; and 2) neither breed has testicular hypoxia, were supported; however, the hypothesis that the relative increase in blood flow is greater in Angus versus Nelore was not supported. Although these were short-term increases in testicular temperature in anesthetized bulls, results did not support the long-standing dogma that increased testicular temperature does not increase testicular blood flow and an ensuing hypoxia is responsible for decreases in motile, morphologically normal and fertile sperm.

Effects of restricted vs. step up dietary adaptation for 6 or 9 days on feedlot performance, feeding behaviour, ruminal and blood variables of Nellore cattle.

This study was designed to determine effects of quantitatively restricted intake of the final finishing diet as a means of dietary adaptation compared with diets increasing in concentrate (step up) over periods of 6 and 9 days on feedlot performance, carcass characteristics, feeding behaviour, blood gas profile and rumen morphometrics of Nellore cattle. One hundred twenty 22-month-old Nellore bulls (352 ± 20 kg) were randomly allocated in 24 pens and fed for 84 days. The experimental design was a completely randomized block with 2 × 2 factorial arrangement of treatments: adaptation using either step up protocol for 6 days or 9 days or restriction protocol for 6 days or 9 days, where the pen (five bullocks/pen; six pens/treatment) was considered the experimental unit. Cattle adapted by step up protocol had significantly greater average daily gain throughout the study when compared to those adapted by restriction protocol, regardless of adaptation length. During the adaptation period, a greater dry matter intake fluctuation was observed for animals maintained on restriction programme when compared to those adapted to the finishing diets using step up protocol. In addition, a protocol × length interaction for rumenitis scores was observed, where the level of injuries to the ruminal wall was significantly higher for the cattle adapted by restriction protocol for 9 days and lower for animals submitted for 9 days to the step up programme. Likewise, a protocol × length interaction for mitotic index was observed, in which cattle adapted by step up protocol for 9 days had lower numbers of cells in mitosis. Thus, the step up protocol led to better feedlot performance, and based on this fact, the length of 9 days promoted better rumen epithelium adaptation of Nellore cattle to high-concentrate diets.

The effect of early measles vaccination at 4.5 months of age on growth at 9 and 24 months of age in a randomized trial in Guinea-Bissau.

BACKGROUND: Providing an early, additional measles vaccine (MV) at 4.5 months of age has been shown to reduce child mortality in low-income countries. We studied the effects on growth at 9 and 24 months of age. METHODS: A randomized controlled trial was conducted in Guinea-Bissau from 2003-2007 including 6,648 children. Children were randomized 1:1:1 to receive Edmonston-Zagreb measles vaccine at 4.5 and 9 months of age (group A), no vaccine at 4.5 months and Edmonston-Zagreb measles vaccine at 9 months (group B), or no vaccine at 4.5 months and Schwarz measles vaccine at 9 months (group C) Data on anthropometrics were obtained at enrolment at 4.5 months of age and again at 9 and 24 months of age. Analyses were stratified by sex, season of enrolment, and neonatal vitamin A supplementation (NVAS) status, as all these factors have been shown to modify the effect of early MV on mortality. RESULTS: Overall there was no effect of early MV on anthropometry at 9 months. At 24 months children who had received early MV had a significantly larger mid-upper-arm-circumference (MUAC/in cm) (Difference = 0.08; 95% CI (0.02;0.14)) compared with children in the control group; this effect was most pronounced among girls (0.12 (0.03;0.20)). The effect of early MV on MUAC remained significant in the dry season and in girls who received placebo rather than NVAS. CONCLUSION: Early MV was associated with a larger MUAC particularly in girls. These results indicate that a two-dose measles vaccination schedule might not only reduce child mortality but also improve growth. TRIAL REGISTRATION: ClinicalTrials.gov NCT00168558 . Registered September 9, 2005, retrospectively registered.

Different effects of BCG strains - A natural experiment evaluating the impact of the Danish and the Russian BCG strains on morbidity and scar formation in Guinea-Bissau.

BACKGROUND: Different Bacillus Calmette-Guerin (BCG) vaccine strains may have different non-specific effects. We assessed the effect of two BCG strains (Danish and Russian) on childhood morbidity and BCG scarification in Guinea-Bissau. METHODS: During 2011-2013, infants in the Bandim Health Project's urban study area received the Danish or Russian BCG in a natural experiment. Health center consultations were registered at point of care and scar status and size at age 4½ months. We assessed the effect of strain on consultation rates between vaccination and age 45days in Cox proportional hazards models. Scar prevalence and size were compared using binomial regression and ranksum tests. RESULTS: Among 1206 children, 18% received Danish BCG (n=215) and 82% Russian BCG (n=991). The adjusted hazard ratio (aHR) for consultations was 0.94 (95% CI 0.60-1.46) for Danish BCG compared with Russian BCG. Girls vaccinated with Danish BCG tended to have lower consultation rates compared with girls vaccinated with Russian BCG (aHR 0.56 (0.25-1.24)), whereas the effect was opposite for boys (aHR 1.24 (0.74-2.11)), p=0.09. Children vaccinated with Danish BCG were more likely to develop a scar (97%) than children vaccinated with Russian BCG (87%), the relative risk (RR) being 1.11 (1.06-1.16). The effect was stronger in girls, and BCG scar size was larger among infants vaccinated with the Danish strain. CONCLUSION: BCG strain influences scar prevalence and scar size, and may have sex differential effects on morbidity. BCG strains are currently used interchangeably, but BCG scarring has been linked to subsequent survival. Hence, more research into the health effects of different BCG strains is warranted. Small adjustments of BCG production could potentially lower childhood morbidity and mortality at low cost.

Valuation of OSA process and folic acid addition as excess sludge minimization alternatives applied in the activated sludge process.

The aim of this study was to investigate the ability of the oxic-settling-anaerobic (OSA)-process and the folic acid addition applied in the activated sludge process to reduce the excess sludge production. The study was monitored during two distinct periods: activated sludge system with OSA-process, and activated sludge system with folic acid addition. The observed sludge yields (Yobs) were 0.30 and 0.08 kgTSS kg(-1) chemical oxygen demand (COD), control phase and OSA-process (period 1); 0.33 and 0.18 kgTSS kg(-1) COD, control phase and folic acid addition (period 2). The Yobs decreased by 73 and 45% in phases with the OSA-process and folic acid addition, respectively, compared with the control phases. The sludge minimization alternatives result in a decrease in excess sludge production, without negatively affecting the performance of the effluent treatment.

Perfil de ácidos graxos e características da carne de bovinos Nelore confinados com diferentes fontes lipídicas protegidas / Fatty acids and meat characteristics of feedlot Nellore cattle with different protected fat sources

O objetivo deste trabalho foi avaliar os efeitos da adição de fontes de lipídeos naturais e protegidos da degradação ruminal na dieta de bovinos Nelore confinados sobre características da carne, concentrações de lipoproteínas sanguíneas e perfil de ácidos graxos da gordura do músculo Longissimus dorsi. Foram utilizados 120 bovinos Nelore, não castrados (366,9±28,7kg), com aproximadamente 24 meses. O delineamento experimental foi inteiramente casualizado, com três tratamentos: (CONTR) sem fonte adicional de lipídeo, (GDESP) com fonte de lipídeo natural (torta de algodão) e (GPROT) com fonte de lipídeo protegido rico em ácidos graxos poli-insaturados. Foram utilizadas 24 baias, cinco animais/baia, com oito repetições/tratamento, sendo as baias consideradas unidades experimentais. Foi observada (P<0,05) interação entre tratamento e dias de mensuração para colesterol e LDL, com maiores valores do tratamento GPROT nos dias 1 e 15, tendo o dia 84 valor intermediário aos demais tratamentos. Observaram-se efeitos de dias de mensuração, em que VLDL e triglicerídeos apresentaram valores crescentes nos dias 15, 84 e 1; enquanto o HDL teve maior valor no dia 1. Foi observado efeito (P<0,05) de tratamento para o perfil de ácidos graxos, com diminuição do C14:1, C16:1 e C17:1 e aumento do ácido transvaccênico, C18:2, ácidos graxos poli-insaturados (AGPI) e da relação AGPI: AGMI (ácidos graxos monoinsaturados) para os tratamentos GPROT e GDESP. Adição de lipídios na dieta, independentemente da fonte, promove melhora na composição de ácidos graxos da carne de bovinos Nelore confinados, aumentando a quantidade de ácidos graxos insaturados sem alterar as características qualitativas da carne.

The objective of this work was to evaluate the effects of adding sources of natural lipids and rumen-protected lipid source rich in polyunsaturated fatty acids to the diet of feedlot Nellore cattle on meat characteristics, blood lipoprotein concentration and fatty acid profile of subcutaneous fat of Longissimus dorsi. One hundred and twenty 24-mo-old Nellore yearling bulls were used (366.9±28.7kg). The experimental design was completely randomized, replicated 8 times (5 bulls/pen), with pens being considered experimental units and consisting of three treatments: (CONTR) without additional source of lipid, (GDESP) with source of natural lipid (cottonseed cake), and (GPROT) with rumen-protected lipid source rich in polyunsaturated fatty acids. Interaction (P<0.05) was observed between treatment and day of measurement for cholesterol and LDL, with values greater GPROT treatment on days 1 and 15, and day 84 intermediate value to the other treatments. Effects (P<0.05) were observed on days of measurement, which showed an increase in VLDL and triglyceride values on days 15, 84 and 1; while HDL had higher values on day 1. Effect (P<0.05) of treatment for the fatty acid profile showed decreased C14:1, C16:1 and C17:1 and increased transvaccênico acid, C18:2, polyunsaturated fatty acids (PUFA) and the ratio PUFA:MUFA (monounsaturated fatty acids) for GPROT and GDESP treatments. Additional fat in the diet, regardless of the source, promotes improvement in fatty acid composition of meat from feedlot Nellore cattle, increasing the amount of unsaturated fatty acids without changing the qualitative characteristics of meat.

Effects of feeding a spray-dried multivalent polyclonal antibody preparation on feedlot performance, feeding behavior, carcass characteristics, rumenitis, and blood gas profile of Brangus and Nellore yearling bulls.

The objective of this study was to evaluate the effects of replacing monensin (MON) with a spray-dried multivalent polyclonal antibody preparation (PAP) against several ruminal microorganisms on feedlot performance, carcass characteristics, feeding behavior, blood gas profile, and the rumenitis incidence of Brangus and Nellore yearling bulls. The study was designed as a completely randomized design with a 2 × 2 factorial arrangement, replicated 6 times (4 bulls per pen and a total of 24 pens), in which bulls ( = 48) of each biotype were fed diets containing either MON fed at 300 mg/d or PAP fed at 3 g/d. No significant feed additive main effects were observed for ADG ( = 0.27), G:F ( = 0.28), HCW ( = 0.99), or dressing percentage ( = 0.80). However, bulls receiving PAP had greater DMI ( = 0.02) and larger ( = 0.02) final LM area as well as greater ( < 0.01) blood concentrations of bicarbonate and base excess in the extracellular fluid than bulls receiving MON. Brangus bulls had greater ( < 0.01) ADG and DMI expressed in kilograms, final BW, heavier HCW, and larger initial and final LM area than Nellore bulls. However, Nellore bulls had greater daily DMI fluctuation ( < 0.01), expressed as a percentage, and greater incidence of rumenitis ( = 0.05) than Brangus bulls. In addition, Brangus bulls had greater ( < 0.01) DMI per meal and also presented lower ( < 0.01) DM and NDF rumination rates when compared with Nellore bulls. Significant interactions ( < 0.05) between biotype and feed additive were observed for SFA, unsaturated fatty acids (UFA), MUFA, and PUFA concentrations in adipose tissues. When Nellore bulls were fed PAP, fat had greater ( < 0.05) SFA and PUFA contents but less ( < 0.01) UFA and MUFA than Nellore bulls receiving MON. For Brangus bulls, MON led to greater ( < 0.05) SFA and PUFA and less ( < 0.05) UFA and MUFA than Brangus bulls fed PAP. Feeding a spray-dried PAP led to similar feedlot performance compared with that when feeding MON. Spray-dried PAP might provide a new technology alternative to ionophores.

Consortia of microalgae and bacteria in the performance of a stabilization pond system treating landfill leachate.

This study treated sanitary landfill leachate and was conducted in a pilot-scale system composed of three serial ponds (P1, P2 and P3), followed by a rock filter, in order to evaluate the microbial consortium influence on system performance and to investigate microorganism dynamics in the process. The system was broken into three stages, with a continuous flow rate (Q = 200 L d⁻¹) for 43 weeks. The stages were as follows: conventional operation (stage I), 12 h aeration in P2 (stage II), and 18 h aeration in P2 (stage III). The results showed the possibilities for treating landfill leachate, presenting an average efficiency of 75% for both filtered biochemical oxygen demand and ammonium. At the end of stage III, the ammonium concentration was 6 mg L⁻¹, which is lower than that established by Brazilian regulations for wastewater discharge (CONAMA 430/2011). The aeration applied in P2 led to a change in the microbial consortia during the second and third stage, which influenced the quality of the final effluent. The best performance was seen in stage III, where the system showed high microbial diversity, including the presence of nitrifying bacteria.

Vaccination of grazing calves with antigens from the intestinal membranes of Haemonchus contortus: effects against natural challenge with Haemonchus placei and Haemonchus similis.

A vaccine containing integral membrane glycoproteins from the intestine of Haemonchus contortus was evaluated in three groups of eight 5 months old grazing calves, naturally infected by Haemonchus similis, Haemonchus placei and other gastrointestinal nematodes. Vaccinated calves received 5 or 50µg of the antigen and 1mg of saponin adjuvant, while the controls received adjuvant alone, initially three times, 3 weeks apart and then four more times at 6 weeks intervals. Three weeks after the last immunisation all of the calves were euthanised for worm counts. Immunisation stimulated high titre antibodies against the vaccine antigens, reduced the egg output of Haemonchus spp. by 85% and the numbers of H. placei and H. similis by 63% and 32%, respectively, compared with control calves. It was concluded that vaccination with intestinal membrane glycoproteins from H. contortus could substantially reduce the transmission of H. placei and H. similis, thus providing protective benefit downstream. This appears to be the first known successful demonstration of a vaccine protective for cattle naturally exposed to infection with any gastrointestinal nematode parasite.

Mini-fasting tests diagnosing endogenous hyperinsulinism: a follow-up of 26 cases.

CONTEXT: The supervised 72-h fast remains the gold standard test for the diagnosis of endogenous hyperinsulinism and has recently been suggested to be shortened or even avoided. OBJECTIVE: This study aimed to evaluate whether measurement of blood glucose, insulin and C-peptide levels after a 12 h overnight fast (mini-fasting test), in at least 3 consecutive days, could allow making or ruling out diagnosis of endogenous hyperinsulinism, according to the Endocrine Society's recent guidelines. PATIENTS AND METHODS: We performed 12 h mini-fasting test in at least 3 consecutive days, dosing blood glucose, insulin and C-peptide levels in 26 inpatient patients with pathologically proven endogenous hyperinsulinism. RESULTS: In our series, 100% of patients showed insulin levels of at least 3 µU/ml and C-peptide levels of at least 0.6 ng/ml concomitant with symptomatic hypoglycemia (≤ 55 mg/dl). CONCLUSION: It leads to the conclusion that mini-fasting test might avoid, in most cases, prolonged fasting test for the diagnosis of hypoglycemia due to endogenous hyperinsulinism.

Aditivos alimentares na dieta de bovinos confinados / Feed additives in feedlot diets

O objetivo do presente trabalho foi avaliar o efeito da inclusão do preparado de anticorpos policlonais (PAP) e/ou da monensina sódica (MON) sobre o desempenho, as características da carcaça, o perfil de ácidos graxos da carcaça (PAG) e a concentração de lipoproteínas sanguíneas (CLS) de bovinos confinados. O delineamento experimental foi inteiramente ao acaso, em arranjo fatorial 2 x 2, com medidas repetidas no tempo, sendo os fatores a inclusão ou não de MON e PAP avaliados em dois períodos, em que 72 bovinos machos da raça Brangus, não castrados, foram alocados em 24 baias (três animais/baia), totalizando seis repetições por tratamento. Não foi observado efeito (P>0,05) da inclusão do PAP para nenhuma das varáveis de desempenho e características de carcaça. Contudo, foi observado efeito (P<0,05) da inclusão de MON, em que animais que receberam MON apresentaram maiores ganho de peso diário (1,666 vs. 1,552), ganho de peso total (179,95 vs. 167,68), peso vivo final (474,86 vs. 459,61), peso de carcaça quente (248,46 vs. 240,20), melhor conversão alimentar (5,57 vs. 5,79) e reduzido custo para ganhar um quilo de peso vivo (3,06 vs. 3,18). Ainda não foi observado efeito principal (P>0,05) dos aditivos para o PAG e a CLS. Assim, a inclusão do PAP não foi boa alternativa à substituição da MON. Por outro lado, a inclusão do PAP não afetou negativamente os itens estudados.

This study was designed to test the effects of polyclonal antibody preparation (PAP) against several rumen bacteria and/or monensin (MON) on feedlot performance, carcass characteristics, fatty acid profile and blood lipoprotein concentrations in yearling bulls. Seventy-two Brangus yearling bulls were distributed in a completely randomized design with 2 x 2 factorial arrangements of treatments with six replications; factors were the inclusion or not of PAP or MON, measured over two phases. No significant (P>0.05) PAP main effects were observed for any of the feedlot performance and carcass trait variables. However, significant (P>0.05) MON main effects were observed, where animals receiving MON had higher (P<0.05) average daily gain (1.666 vs. 1.552), total weight gain (179.95 vs. 167.68), final body weight (474.86 vs. 459.61), hot carcass weight (248.46 vs. 240.20), better feed: gain ratio (5.57 vs. 5.79) and better cost to gain one kilo of body weight (3.06 vs. 3.18). No significant (P>0.05) main effects due to feed additives were observed for carcass fatty acid profile and blood lipoprotein concentrations. Therefore, the inclusion of PAP was not a good alternative to replace MON. On the other hand, feeding PAP did not negatively impact the items studied.

Effects of feeding a multivalent polyclonal antibody preparation on feedlot performance, carcass characteristics, rumenitis, and blood gas profile in Bos indicus biotype yearling bulls.

The objective of this study was to evaluate effects of feeding monensin (MON) or a multivalent polyclonal antibody preparation (PAP) against several rumen microorganisms on feedlot performance, carcass characteristics, blood gas profile, and rumenitis of Bos indicus biotype (BT) yearling bulls. The study was designed as a completely randomized design with a 3 × 2 factorial arrangement, replicated 4 times, in which 32 yearling bulls of each of 3 BT evaluated (3-way-cross, TC; Canchim, CC; and Nellore, NE) were fed diets containing either MON at 300 mg·d(-1) or PAP at 10 mL·d(-1) across 3 different periods. No significant (P > 0.10) feed additive (FA) main effects were observed for any of the feedlot performance variables and carcass characteristics with the exception of dressing percentage. Yearling bulls receiving PAP had a decreased (P = 0.047) dressing percentage when compared with yearling bulls receiving MON. Significant (P < 0.05) BT main effects were observed for all feedlot performance variables and carcass characteristics with the exception of kidney-pelvic fat expressed in kilograms (P = 0.49) and LM lipids content (P = 0.45). Crossbred yearling bulls (TC and CC) had greater (P < 0.001) ADG, DMI in kilograms, DMI as % of BW, and improved (P = 0.001) G:F when compared with NE yearling bulls. A tendency (P = 0.072) for a FA main effect was observed for rumenitis scores, in which yearling bulls receiving PAP had lesser rumenitis scores than those receiving MON. When the data were disposed as frequency percentage, 55.6% and 45.7% of the rumens from yearling bulls fed PAP and MON were scored between 0 and 1, respectively (0 = no lesions, 10 = severe lesions). Likewise, a significant BT main effect was observed (P = 0.008), where NE yearling bulls had greater rumenitis scores than those of crossbred yearling bulls (TC and CC). No significant FA main effects were observed (P > 0.10) for any of the fatty acids measured in the subcutaneous adipose tissue, with the exception that yearling bulls receiving MON had greater (P < 0.05) concentrations of palmitic acid (16:0), margaric acid (17:0), docosapentaenoic acid (22:5), and docosahexaenoic acid (22:6) than those yearling bulls receiving PAP. Feeding PAP tended to decrease incidence of rumen lesions and led to similar feedlot performance compared with feeding MON. Thus, PAP is a new technology that presents a possible alternative for ionophores.

Glucagon test in insulinoma: Is it useful?

Diagnosis of endogenous hyperinsulinism caused by insulinoma is based on confirmation of hypoglycemia during the symptoms associated to elevated insulin levels. Patients with insulinoma may demonstrate an excessive insulin response and subsequent hypoglycemia after 1 mg of glucagon iv injection. Glucagon test was performed in 11 patients with insulinoma before therapy and in 4 after therapy. Our study suggests that the presence of plasma glucose levels less than 55 mg/dl and below baseline at time 120 min of glucagon test strongly reinforce the diagnosis of insulinoma.

Effects of adding polyclonal antibody preparations on ruminal fermentation patterns and digestibility of cows fed different energy sources.

Nine ruminally cannulated cows fed different energy sources were used to evaluate an avian-derived polyclonal antibody preparation (PAP-MV) against the specific ruminal bacteria Streptococcus bovis, Fusobacterium necrophorum, Clostridium aminophilum, Peptostreptococcus anaerobius, and Clostridium sticklandii and monensin (MON) on ruminal fermentation patterns and in vivo digestibility. The experimental design was three 3 × 3 Latin squares distinguished by the main energy source in the diet [dry-ground corn grain (CG), high-moisture corn silage (HMCS), or citrus pulp (CiPu)]. Inside each Latin square, animals received one of the feed additives per period [none (CON), MON, or PAP-MV]. Dry matter intake and ruminal fermentation variables such as pH, total short-chain fatty acids (tSCFA), which included acetate, propionate, and butyrate, as well as lactic acid and NH(3)-N concentration were analyzed in this trial. Total tract DM apparent digestibility and its fractions were estimated using chromic oxide as an external marker. Each experimental period lasted 21 d. Ruminal fluid sampling was carried out on the last day of the period at 0, 2, 4, 6, 8, 10, and 12 h after the morning meal. Ruminal pH was higher (P = 0.006) 4 h postfeeding in MON and PAP-MV groups when compared with CON. Acetate:propionate ratio was greater in PAP-MV compared with MON across sampling times. Polyclonal antibodies did not alter (P > 0.05) tSCFA, molar proportion of acetate and butyrate, or lactic acid and NH(3)-N concentration. Ruminal pH was higher (P = 0.01), 4 h postfeeding in CiPu diets compared with CG and HMCS. There was no interaction between feed additive and energy source (P > 0.05) for any of the digestibility coefficients analyzed. Starch digestibility was less (P = 0.008) in PAP-MV when compared with CON and MON. In relation to energy sources, NDF digestibility was greater (P = 0.007) in CG and CiPu vs. the HMCS diet. The digestibility of ADF was greater (P = 0.002) in CiPu diets followed by CG and HMCS. Feeding PAP-MV or monensin altered ruminal fermentation patterns and digestive function in cows; however, those changes were independent of the main energy source of the diet.

A comparison of ex vivo cytokine production in venous and capillary blood.

We performed a randomized study of the immunological effects of an early measles vaccine given at 4.5 months of age and aimed to obtain venous samples from the infants at baseline and 6 weeks later. If this was not feasible, a capillary sample was obtained. We analysed baseline samples from the first 50 children enrolled in the study to investigate the potential differences in ex vivo cytokine production between venous blood and capillary blood. We also obtained paired venous and capillary blood samples from 11 adult volunteers. Whole blood was stimulated with lipopolysaccharide (LPS) [a Toll-like receptor (TLR)-4 ligand], (S)-(2, 3-bis (palmitoyloxy)-(2-RS)-propyl)-N-palmitoyl-(R)-Cys-(S)-Ser-(S)-Lys4-OH, trihydrochloride (PAM3Cys) (a TLR-2 ligand), phytohaemagglutinin (PHA) or purified protein derivative (PPD). Cytokine concentrations in the supernatants were assessed by a multiplexed assay and were compared between venous and capillary samples in both infants and adults. The production of both the pro- and the anti-inflammatory cytokines, tumour necrosis factor (TNF)-alpha and interleukin (IL)-10, was higher in cultures of capillary blood compared with venous blood. This was found in non-stimulated control samples as well as in blood stimulated with PAM3Cys and PPD. Adults produced more IL-5 in venous blood than in capillary blood upon PHA stimulation. We found no other difference in the levels of IL-5 or IFN-gamma between venous and capillary blood. In capillary blood we found sex differences in response to PHA but this was not the case in venous blood. We found significant differences in the production of cytokines between venous and capillary blood. Such differences should be taken into account when setting up immuno-epidemiological studies.

Expression at mRNA level of cytokines and A238L gene in porcine blood-derived macrophages infected in vitro with African swine fever virus (ASFV) isolates of different virulence.

Porcine macrophage cultures were infected with two ASFV isolates of variable virulence and mRNA levels of several relevant macrophage-derived cytokines were quantified by real time PCR. At six hours post infection, a clear enhancement of mRNA expression of TNFalpha, IL6, IL12 and IL15 was observed in macrophages infected with the low virulent ASFV/NH/P68 (NHV) when compared to those infected with the highly virulent ASFV/L60 (L60). The sequence of the A238L gene homologue to the cellular IkappaB was found identical in both viral isolates and its expression at mRNA level was higher in macrophages infected with NHV when compared to macrophages infected with L60. Furthermore our results suggest a negative correlation between the mRNA expression of A238L gene and the mRNA expression of the above mentioned cytokines (with the exception of IL10) in L60 infected macrophages in opposition to the positive correlation (with exception of the IL1) suggested in NHV infection. Overall, our data strongly emphasize that virulence of ASFV isolates may depend on their capacity to regulate the expression of macrophage-derived cytokines relevant for the development of host protective responses by yet unknown mechanisms triggered by the virus at early stages of the cellular infection.

BCG vaccination among West African infants is associated with less anergy to tuberculin and diphtheria-tetanus antigens.

To examine risk factors for anergy, delayed-type hypersensitivity was assessed among 884 infants participating in a vaccine trial in Guinea-Bissau. The infants were skin-tested at 7.5 months of age with a panel of seven intradermal antigens. Risk factors for anergy to tuberculin or anergy to both the diphtheria and tetanus antigens were determined in relation to Bacillus Calmette-Guérin (BCG) vaccination, diphtheria-tetanus-pertussis (DTP) vaccination, and measles vaccination. We found sick children to be more anergic to tuberculin and diphtheria-tetanus antigens than healthy children (OR=2.49 (95% confidence interval 1.40-4.55)). There was a higher prevalence of anergy to tuberculin in the rainy season than in the dry season (OR=1.67 (1.25-2.23)). Children who had taken antimalarials within the last week had a higher prevalence of anergy to tuberculin (OR=1.41 (1.02-1.92)). BCG vaccination was significantly associated with less anergy to tuberculin and diphtheria-tetanus antigens (OR=0.42 (0.28-0.63), OR=0.77 (0.60-0.99), respectively). Children vaccinated with BCG before 1 month of age were more anergic to tuberculin than children vaccinated after 1 month (OR=1.61 (1.19-2.19)). DTP vaccination was associated with less anergy to diphtheria-tetanus antigens (OR=0.40 (0.32-0.49)), but not to tuberculin. Children with a positive reaction to tuberculin were less likely to be anergic to diphtheria-tetanus antigens (OR=0.36 (0.26-0.49)) than children with a negative tuberculin reaction. Children who were vaccinated with BCG before they received their last DTP vaccine were less anergic to diphtheria-tetanus antigens (OR=0.40 (0.16-0.88)) than other DTP-vaccinated children. In conclusion, current disease, rainy season, age below 1 month of age at the time of BCG vaccination, and administration of chloroquine or quinimax within the last 7 days were risk factors for anergy to tuberculin among 7.5-month-old infants. BCG vaccination and a positive tuberculin reaction were associated with a lower prevalence of anergy to both tuberculin and diphtheria-tetanus. Thus, BCG vaccination may contribute to better cell-mediated immune responses among infants.

Measles antibody responses after early two dose trials in Guinea-Bissau with Edmonston-Zagreb and Schwarz standard-titre measles vaccine: better antibody increase from booster dose of the Edmonston-Zagreb vaccine.

In Guinea-Bissau, children were randomised at 6 months of age to receive either two doses of standard-titre measles vaccine at 6 and 9 months of age or an inactivated polio vaccine at 6 months and standard-titre measles vaccine at 9 months of age. During the first 5 months, children received Edmonston-Zagreb (EZ) vaccine and during the following 11 months, the Schwarz (SW) vaccine. Five percent of the mothers, 74% of children at 6 months of age, and 92% of unvaccinated children at 9 months of age had unprotective levels (<125 mIU/ml) of measles antibodies. Among children receiving EZ vaccine, 1% were unprotected at 18 months of age after either two (3/240) or one (3/211) doses of vaccine, the geometric mean measles antibody titre (GMT) being approximately 1550 mIU/ml in both groups. Among those receiving SW vaccine 9% (34/365) and 3% (9/310) were unprotected at 18 months of age in the two-dose and the one-dose groups (RR = 3.21 (95% confidence interval (CI) 1.56-6.58)), respectively. The GMT was higher after one dose of SW vaccine at 9 months of age (2491 mIU/ml) than after two doses of SW vaccine (1125 mIU) (P < 0.001). In the EZ vaccine group, there was no significant difference in antibody level for children vaccinated in the presence of high or low levels of maternal antibodies, whereas there was a marked difference in the SW group. The second EZ vaccine induced a significant antibody increase between 9 months of age (1191 mIU) and 18 months of age (1602 mIU, P=0.011), whereas antibody levels tended to decline from 9 months (1243 mIU) to 18 months of age (998 mIU, P = 0.124) after the second dose of SW vaccine. Conclusively, after two doses of EZ measles vaccine more children were protected at 18 months of age than after two doses of SW. One dose of SW provided the highest antibody response, but a higher proportion of unprotected than one or two doses of EZ. The EZ vaccine was less sensitive to maternal antibodies, and able to increase the antibody response by revaccination, while the second SW vaccine resulted in an unchanged or lower antibody response.

Bacterial lipoprotein based expression vectors as tools for the characterisation of African swine fever virus (ASFV) antigens.

African swine fever virus (ASFV) is the causative agent of an important pig disease for which protective mechanisms are still poorly understood. The present work was aimed at the characterisation of ASFV antigens using previously reported vectors that allow their expression as fusion proteins with the bacterial lipoprotein OprI. Several recombinant clones induced SLA-restricted, ASFV-specific lymphoproliferation and one (A2) was demonstrated to stimulate ASFV-specific CTL activity in vitro, in opposition to the effect of UV inactivated virus. The nucleotide sequence of the fragment cloned in A2 showed 99% identity with a portion of the G1340L ORF of the BA71V isolate, and the expressed fusion lipoprotein induced specific antibodies in vivo. Blood mononuclear leukocytes from a pig immunised with outer membrane preparations from A2 showed to reduce strongly (99.6%) the ASFV yield in cultures of autologous macrophages. However, after inoculation with virulent virus the pig developed acute fatal ASF. Overall our results show that OprI based expression vectors are valuable tools to screen viral antigens in terms of their capacity to trigger immune competent cells.