Efeito da suplementação de colina protegida no perfil metabólico e intervalo entre parto e concepção de vacas leiteiras / Prepartum supplementation of protected choline on metabolic profile and interval between calving and conception of dairy cows

Durante o periparto, as vacas leiteiras são submetidas a uma grande demanda de energia, ao mesmo tempo em que reduzem sua ingestão de matéria seca. O balanço energético negativo, resultante dessa equação, acarreta severos transtornos metabólicos, à produção e, principalmente, à reprodução. O objetivo do presente estudo foi avaliar o efeito da colina protegida sobre os parâmetros metabólicos, o intervalo entre parto e concepção e a produção de leite em vacas no período de transição. Cinquenta e quatro vacas leiteiras foram divididas em três grupos: controle, suplementação com colina por 10 dias pré-parto (T10) e suplementação com colina por 20 dias pré-parto (T20). Após o parto, foram mensurados os teores de frutosamina, colesterol, ácidos graxos não esterificados (AGNE), beta-hidroxibutirato (BHB), aspartato aminotransferase (AST), gamaglutamiltransferase (GGT) e total de oxidantes (TOS), nos dias 10, 20 e 30. Ainda foram avaliadas produção de leite e intervalo entre parto e concepção. Não houve efeito da suplementação com colina sobre os parâmetros sanguíneos e a produção. O intervalo entre parto e concepção foi menor no grupo T20. A colina suplementada por 20 dias durante o pré-parto melhorou a performance reprodutiva de vacas leiteiras(AU)

During the periparturient dairy cows undergo a large energy demand, at the same time reducing their intake of dry matter. The negative energy balance resulting from this equation leads to severe metabolic disorders in production, and mainly in reproduction. The aim of this study was to evaluate the effect of protected choline on metabolic parameters, reproductive performance, and milk production in cows during the transition period. Fifty-four dairy cows were divided into three groups: control, supplementation with choline for 10 days prepartum (T10) and supplementation with choline for 20 days prepartum (T20). After delivery we measured fructosamine levels, cholesterol, non-esterified fatty acids (NEFA), beta-hydroxybutyrate (BHB), aspartate aminotransferase (AST), gamma glutamyltransferase (GGT), and total oxidant (TOS) on days 10, 20 and 30. We also evaluated milk production and interval between calving and conception. There was no effect of supplementation with choline on blood and production parameters. The interval between calving and conception was lower in the T20 group. Choline supplemented by 20 during the antepartum improved reproductive performance of dairy cows, although it did not change the metabolic profile.(AU)

Efeito do uso de minerais traços (cobre, zinco, selênio e manganês) e vitaminas (A e E) injetáveis sobre o estresse oxidativo e função de neutrófilos de fêmeas da raça Holandesa no período de transição / Effect of use of injected trace minerals (copper, zinc, selenium, and manganese) and vitamins (A and E) on oxidative stress and neutrophil function in females of Hostein cows during transitionl

O objetivo deste estudo foi avaliar o efeito metafilático de minerais traços e vitaminas A e E injetáveis, em parâmetros do estresse oxidativo e na função de neutrófilos em fêmeas da raça Holandesa no período de transição. Sessenta animais foram divididos em dois grupos: animais que receberam minerais traços e vitaminas A e E injetáveis (GMTV) (n= 30) e grupo controle (GC) (n= 30). Não houve diferença significativa entre os grupos nos parâmetros avaliados, porém observou-se diferença significativa entre tratamento e dia para os valores da SOD, com maior atividade dessa enzima em fêmeas GMTV, nas semanas próximas ao parto. Observou-se diferença de dia e para interação tratamento e dia para o TBARS, em que fêmeas GMTV mostraram menores valores de TBARS em todos os momentos, exceto sete dias após o parto. Houve efeito significativo de dia para leucócitos, interação tratamento e dia para neutrófilos e interação tratamento e dia para fagocitose de neutrófilos, em que as fêmeas GMTV apresentaram valores menores de leucócitos e neutrófilos próximo ao parto, além de maior fagocitose de neutrófilos. Pode-se observar que houve melhora no sistema oxidativo e imune de fêmeas GMTV, resposta que provavelmente está relacionada com a administração dos minerais traços e vitaminas A e E.(AU)

This study evaluates the metaphylactic of the subcutaneous administration of a trace minerals and vitamins A and E, on the oxidative stress and neutrophil function in Holsteins cows under the transition period. Sixty females were divided in two groups: group with trace minerals and vitamins (GMTV) (n= 30) and group control (GC) (n= 30). There was no significant difference between those groups; however, we find significant difference between treatment and day for Superoxide dismutase (SOD) values with higher activity of this enzyme in females GMTV on the weeks next to the parturition. Still, there was difference on day and, for interactions between treatment and day for TBARS, were females GMTV showed lower values of TBARS in all moments, except on day seven after the parturition. For leucocytes, there is a significant effect by day, interaction on treatment and day on neutrophils, and interaction treatment and day for neutrophil phagocytosis, were females GMTV showed lower values of leucocytes and neutrophils next to the parturition, and an increase of neutrophils phagocytosis. In summary, cows from the GMTV group had an improvement on the immune and oxidative systems, probably correlated with the administration of this supplement.(AU)

Metaphylactic effect of minerals on the immune response, biochemical variables and antioxidant status of newborn calves.

The aim of this study was to evaluate whether injectable zinc and copper affect host immune responses and antioxidant status of newborn calves. For this study, 19 newborn calves were divided into two groups. The control group consisted of 10 animals; and the treated group consisted of nine animals that received copper edetate (Cu-ed) and zinc edetate (Zn-ed) subcutaneously at the first day of life at doses of 0.3 mg/kg and 1.0 mg/kg respectively. Blood and faecal samples were collected for laboratory analyses (seric biochemistry, proteinogram, antioxidant enzymes and parasitological examination) on days 10, 20 and 30 after birth. On day 10, treated animals showed increased levels of total proteins, as well as increased globulin levels compared to the control group, a finding probably related to the increase in ceruloplasmin and IgG heavy chain. Thirty days after mineral metaphylactic administration, IgG light chain and acid glycoprotein levels significantly increased in treated animals (p < .05). There were no significant differences between groups regarding the biochemical analyses (triglycerides, cholesterol, glucose and urea). On the other hand, the superoxide dismutase and catalase activities increased on day 10 after treatment. In the control group, eight animals showed severe diarrhoea and one died 8 days after birth. Two animals from this group showed mild diarrhoea. Only three treated animals had severe diarrhoea, and six showed signs of mild diarrhoea. All animals that showed severe diarrhoea (control = 8; treated = 3) had hyperthermia (over 39.5°C), and therefore, antibiotic therapy was administered (sulfadiazine and trimethoprim) for five consecutive days. In summary, Zn-ed and Cu-ed decreased the frequency and intensity of diarrhoea, modulated superoxide dismutase (SOD) and catalase (CAT) enzymes and also heightened the immune responsiveness of newborn calves, suggesting a new approach to improve cattle performance and minimize the occurrence of diarrhoea.

Distribution of selenium in sheep treated with dipheny diselenide / Distribuição do selênio em ovinos tratados com disseleneto de difenila

The aim of the present study was to report the in vivo distribution of selenium in sheep. For this, animals were allocated into two groups (control group and treated group) and kept in metabolic cages for a period of 37 days. The treated group received a single dose (6µmol/kg) of Diphenyl Diselenide, intravenously. Plasma and erythrocytes samples were collected at different times. Adipose tissue, muscles (latissimusdorsi, semitendinosus, and supra-scapular) heart, liver, lung, kidney, intestine and brain were sampled at 30 days post-treatment, in order to determine the selenium concentration. The results demonstrated that the selenium, from the Diphenyl Diselenide group, was higher in erythrocytes (4.8mg/L, six hours post-treatment) when compared with the control sheep. The deposition of selenium occurred in the liver (7.01µg/g), brain (3.53µg/g) and kidney (2.02µg/g). After 30 days of a single intravenous injection of Diphenyl Diselenide, liver was the main organ of selenium deposition.(AU)

O objetivo do presente estudo foi investigar a distribuição in vivo do selênio em ovinos. Para isso, os animais foram distribuídos em dois grupos (grupo controle e grupo tratado) e mantidos em gaiolas metabólicas por um período de 37 dias. O grupo tratado recebeu uma dose única (6µmol/kg) de disseleneto de difenila, por via intravenosa. As amostras de plasma e de eritrócitos foram recolhidas em momentos diferentes. Tecido adiposo, músculos (latissimus dorsi, semitendinoso e supraescapular) coração, fígado, pulmão, rim, intestino e cérebro foram amostrados aos 30 dias pós-tratamento, a fim de se determinar a concentração de selênio. Os resultados demonstraram que o selênio, do grupo disseleneto de difenila, foi maior em eritrócitos (4,8mg/L, seis horas após o tratamento) quando comparado com o grupo controle. A deposição de selênio ocorreu no fígado (7,01µg/g), cérebro (3,53µg/g) e rim (2,02µg/g). Após 30 dias de uma única injeção intravenosa de disseleneto de difenila, o fígado foi o principal órgão de deposição de selênio.(AU)

Efeito metafilático do zinco injetável sobre parâmetros metabólicos e oxidativos de ovelhas no pós-parto imediato / Metaphylactic effect of injectable zinc on metabolic and oxidative parameters of sheep in the immediate postpartum

The aim of this study was to evaluate a new source of injectable organic zinc (zinc edetate) on the energy and oxidative profile in sheep during the immediate postpartum period. Twenty-six Texel breed animals were previously identified and divided into two experimental groups: the treated group (TG; n= 13) that comprised the animals that received a subcutaneous (SC) injection of 100 mg of zinc edetate (2 mL) fifteen days before the parturition expected date and the control group (CG; n=13) that comprised the animals that received 2mL of physiological solution at the same date of TG. Blood samples were collected on the parturition day for the assessment of serum fructosamine, cholesterol and triglycerides, insulin-like growth factor type 1 (IGF-1), the oxidative stress index (OSi) and blood zinc concentration. In addition to these parameters, the measurement of zinc was made in food given to the animals. There was no difference in metabolic parameters and OSi between the experimental groups (P>0.05), as well as in blood zinc concentrations (P>0.05). The parenteral zinc edentate does not change the energy and oxidative profile of sheep in immediate postpartum.(AU)

Efeito da suplementação com colina protegida sobre parâmetros bioquímicos, produção e reprodução de vacas leiteiras no periparto / Effect of protected choline supplementation on biochemical parameters, production, and reproduction of dairy cows in peripartum

Avaliou-se o efeito da suplementação com colina protegida sobre o perfil energético, as enzimas hepáticas e a reprodução de vacas leiteiras no periparto. Quinze vacas leiteiras foram divididas em dois grupos experimentais: oito receberam 80 gramas de colina protegida por 21 dias no pré-parto e por 40 dias no pós-parto e sete foram consideradas controle. Amostras de sangue foram coletadas nos dias 10, 20, 30 e 60 pós-parto para avaliação dos perfis energético e hepático. Aos 60 dias pós-parto, realizou-se exame ginecológico dos animais para avaliação da saúde reprodutiva. A suplementação com colina protegida não alterou os níveis de beta-hidroxibutirato (BHBA), ácidos graxos não esterificados (AGNE), frutosamina, fator de crescimento semelhante a glicose I (IGF-I), status oxidante total (TOS), aspartato aminotransferase (AST) e gamaglutamiltransferase (GGT) no pós-parto. Não houve diferença também quanto à produção de leite. Aos 60 dias pós-parto, vacas suplementadas com colina protegida apresentaram menor número de casos de endometrite que vacas do grupo controle. A suplementação de colina protegida não alterou o perfil bioquímico e a produção de leite, mas reduziu o número de casos de endometrite no pós-parto de vacas leiteiras.(AU)

The study aimed to evaluate the effect of supplementation with protected choline on the energy profile, liver enzymes and reproduction in dairy cows in peripartum. Fifteen cows were divided into two groups: 8 received 80 grams of protected choline for 21 days pre-partum and 40 days postpartum, and 7 were considered control. Blood samples were collected on days 10, 20, 30, and 60 postpartum to evaluate the energy and hepatic profiles. After 60 days postpartum a gynecological examination of animals for evaluation of reproductive health was done. The supplementation with choline protected did not alter the beta-hydroxybutyrate levels (BHBA), non-esterified fatty acids (NEFA), fructosamine, like growth factor glucose (IGF-I), total oxidant status (TOS), aspartate aminotransferase (AST) and glutamiltrasferase range (GGT) postpartum. There was no difference in milk production. After 60 days postpartum, cows fed protected choline had fewer cases of endometritis that cows in the control group. The protected choline supplementation did not alter the biochemical profile and milk production, but reduced the number of endometritis cases in postpartum dairy cows.(AU)

In vitro activity of essential oils of free and nanostructured Melaleuca alternifolia and of terpinen-4-ol on eggs and larvae of Haemonchus contortus.

Haemonchus contortus is one of the major gastrointestinal nematodes responsible for significant economic and production losses of sheep. Diseases caused by this species lack effective anthelmintic products, and the search for new compounds to replace synthetic anthelmintics has been extensive. The present investigation assesses the in vitro activity of the essential oil of melaleuca (Melaleuca alternifolia), both free (TTO) and nanostructured (nanoTTO), and terpinen-4-ol (terp-4-ol) on eggs and larvae of H. contortus. Tests of egg hatching (EHT) and inhibition of larval migration (LMIT) were used to assess the in vitro efficacy of TTO, nanoTTO and terp-4-ol. Using EHT, at a concentration of 3.5 mg/ml, 100% inhibition occurred using TTO and terp-4-ol, with LC50 values of 0.43 and 0.63 mg/ml, and LC90 values of 1.75 mg/ml and 3.12 mg/ml, respectively. NanoTTO had lower activity, with 82.6% inhibition at the same concentration. Using LMIT, TTO and nanoTTO had a similar activity with 88.0% and 84.8% inhibition, respectively, at a concentration of 56 mg/ml. Terp-4-ol had a greater effect on larvae, with 85.7% inhibition at a concentration of 56 mg/ml and 82.4% at 3.5 mg/ml, demonstrating high activity at the lowest concentration tested. Therefore, the results indicate that all substances tested showed ovicidal and larvicidal activity against H. contortus. TTO, terp-4-ol and, mainly, nanoTTO may be targeted in in vivo studies, besides being a promising line of research into the control and treatment of veterinary important helminths.

Intravenous hypertonic saline solution (7.5%) and oral electrolytes to treat of calves with noninfectious diarrhea and metabolic acidosis.

OBJECTIVE: The aim of this study was to compare the efficacy of treating osmotic diarrhea and dehydration in calves with hypertonic saline solution (HSS) IV, isotonic electrolyte solution (IES) PO, and a combination of these 2 solutions (HSS + IES). EXPERIMENTAL DESIGN: Eighteen male calves 8-30 days of age were used to evaluate the efficacy of 3 methods of fluid therapy after induction of osmotic diarrhea and dehydration. The diarrhea and dehydration were induced by administration of saccharose, spironolactone, and hydrochlorothiazide for 48 hours. The animals were randomly divided into 3 experimental groups: Group 1: 7.2% hypertonic saline solution-HSS (5 mL/kg IV); Group 2: oral isotonic electrolyte solution IES (60 mL/kg PO); or Group 3: HSS+IES. Clinical signs and laboratory finding observed 48 hours post-induction (Time 0) included diarrhea, dehydration, lethargy, and metabolic acidosis. RESULTS: Calves treated with HSS + IES experienced decreases in hematocrit, total protein concentration, albumin concentration, urea nitrogen concentration, and plasma volume as well as increases in blood pH, blood bicarbonate concentration, and central venous pressure between 1 and 3 hours post-treatment. These findings also were observed in animals treated with IES, however, at a slower rate than in the HSS + IES-treated animals. Animals treated with HSS continued to display signs of dehydration, lethargy, and metabolic acidosis 24 hours post-treatment. CONCLUSION: Treatment with a combination of HSS and IES produced rapid and sustainable correction of hypovolemia and metabolic acidosis in calves with noninfections diarrhea and dehydration.

Eficácia do óleo de citronela [Cymbopogon nardus (L. ) Rendle] no controle de ectoparasitas de bovinos / Efficacy of citronella [Cymbopogon nardus (L. ) Rendle] oil in the control of bovine ectoparasites

O objetivo desta pesquisa foi avaliar o efeito in vivo do óleo de citronela, no controle do carrapato bovino [Rhipicephalus (Boophilus) microplus], da mosca-dos-chifres (Haematobia irritans), da mosca-dos-estábulos (Stomoxys calcitrans) e da mosca doméstica (Musca domestica). Foram utilizadas 15 vacas da raça Holandês, distribuídas em três grupos de cinco animais cada um. Os tratamentos foram: controle negativo, amitraz a 0,025 por cento e óleo de citronela a 4 por cento. Para avaliação foram contadas fêmeas ingurgitadas de carrapato e moscas antes (média dos dias -3, -2, -1) e após a aplicação dos produtos nos dias 7, 14, 21 e 28; também foram coletadas amostras de sangue. Em 28 dias, houve necessidade de se reaplicar o amitraz e o fitoterápico para controlar a infestação com carrapato. A relação entre o número de aplicações foi de 1:2,5 para o amitraz e o óleo de citronela, respectivamente. A eficácia no controle do carrapato foi de 71,8 e 30,9 por cento para o amitraz e óleo de citronela a 4 por cento, respectivamente, na média pós-tratamento. Verificou-se baixo controle de moscas no tratamento constituído pelo fitoterápico. Não houve diferença entre os tratamentos para os parâmetros sanguíneos.

This study aimed to evaluate the in vivo effect of citronella oil on the control of bovine ticks [Rhipicephalus (Boophilus) microplus], horn flies (Haematobia irritans), stable flies (Stomoxys calcitrans) and houseflies (Musca domestica). Fifteen Holstein cows were allocated to three groups of five animals each. The treatments were: negative control, amitraz at 0.025 percent and citronella oil at 4 percent. Engorged female ticks and flies were counted before (mean of days -3, -2, -1) and at 7, 14, 21 and 28 days after treatment; blood samples were also collected. Within 28 days, amitraz and the phytotherapic agent had to be reapplied to control tick infestation. The relationship among the number of applications was 1:2.5 for amitraz and citronella oil, respectively. The efficacy of tick control was, on average, 71.8 and 30.9 percent for amitraz and citronella oil at 4 percent respectively, post-treatment. Lower control of flies was observed for the phytotherapic group. There was no difference among treatments for blood parameters.

Neutrophil oxidative metabolism and haemogram of sheep experimentally infected with Haemonchus contortus and supplemented with selenium and vitamin E.

The objective of this study was to evaluate neutrophil oxidative metabolism and haemogram in sheep experimentally infected with Haemonchus contortus and supplemented with selenium and vitamin E. Twenty male Corriedale sheep were utilised and distributed into four experimental groups each with five animals infected with larvae: G1--supplemented with sodium selenite, 0.2 mg/kg body weight (bw) given intramuscularly (IM); G2--supplemented with sodium selenite and vitamin E, 0.2 mg/kg bw and 2000 IU per animal, respectively, both IM; G3--supplemented with vitamin E, 2000 IU per animal IM; G4--not supplemented. A haemogram and the number of parasite eggs were determined in samples of blood and faeces, respectively, on days zero (T0), 20 (T1), 40 (T2) and 60 (T3) and nitroblue tetrazolium (NBT) assays were performed on heparinized blood samples taken on days zero, 30 and 60. A lower total leucocyte count was detected in G1 in relation to G4 at T4. Lymphocytes were reduced in G1 in relation to G3 and G4 at T3. In both non-stimulated (NBT-NS) and stimulated (NBT-S) dye reduction assays, there was reduced activity at 60 days, in relation to other times in the groups treated with selenium (G1 and G2). On the basis of results obtained, we conclude that supplementation with selenium provides better antioxidant protection to neutrophils.

Isolamento de Corynebacterium pseudotuberculosis no sêmen de um carneiro na região central do Rio Grande do Sul / Isolation of Corynebacterium pseudotuberculosis from the semen of a sheep in the central region of Rio Grande do Sul, Brazil

O presente trabalho descreve o isolamento do Corynebacterium pseudotuberculosis no sêmen de um carneiro da raça Suffolk proveniente do Município de São Martinho da Serra, RS. Ao exame físico constatou-se aumento de volume subcutâneo aderido à pele, junto à inserção do escroto, próximo ao plexo pampiniforme esquerdo. Realizou-se exame andrológico com coleta de sêmen e, posteriormente, punção no local da lesão, obtendo-se material viscoso de coloração amarelo esverdeado. As amostras coletadas (sêmen e material obtido da punção) foram enviadas ao LABAC (Laboratório de Bacteriologia Veterinária da Universidade Federal de Santa Maria) para realização de cultura bacteriana. Em ambas as amostras, foi isolado o cocobacilo Gram positivo denominado C. pseudotuberculosis.

The present paper describes the isolation of Corynebacterium pseudotuberculosis from a semen sample of a Suffolk ram from São Martinho da Serra County, state of Rio Grande do Sul, Brazil. Physical examination revealed a subcutaneous mass close to the insertion of the scrotum, more specifically around the left pampiniform plexus. A routine andrological exam with semen collection was performed. Also, the mass was aspirated yielding a viscous greenish material. Samples were sent to a bacteriology lab for culture and identification. Gram positive coccobacillus C. pseudotuberculosis was isolated from both samples.

Estudo da capacidade alcalinizante de tampões metabolizáveis em bovinos sadios / The alkalinizing effects of different metabolizable buffers in healthy steers

Seis novilhos mestiços, com cerca de 250kg e um ano de idade, foram infundidos, no decorrer de quatro horas, com cinco litros de diferentes soluções isotônicas de sais sódicos, com 150mM/l de bicarbonato, acetato, propionato, lactato L, lactato racêmico e cloreto (controle), em delineamento em quadrado latino (6x6). Análises hemogasométricas e do pH urinário foram determinadas no decorrer da infusão - zero, primeira e quatro horas - e após o seu término, na oitava hora. O pH do sangue foi maior nos animais infundidos com os tampões que nos infundidos com cloreto; teores mais elevados de bicarbonato e de excesso de ácido-base sanguíneos foram obtidos na quarta e oitava hora nos infundidos com bicarbonato e lactato; o mesmo ocorreu com a pressão de CO2 na oitava hora. Os resultados indicam que os tratamentos com Bicarbonato e lactato proporcionam acúmulo de tampões no sangue e geram discreta alcalose metabólica, compensada organicamente por leve retenção de CO2. a infusão com bicarbonato de sódio causa elevação do pH urinário

Six healthy crossbred yearling 250kg steers were infused intravenously, during four hours, with five liters of each of the six different isotonic solutions of sodium salts containing 150 mMol/l of the bicarbonate, acetate, propionate, L-lactate, D and L-lactate and chloride in a 6 x 6 latin square experimental design. Blood was collected from the jugular vein, anaerobically, for blood gas analysis, samples were obtained at different times throughout the infusion (zero, 1st, 4th and 8th h ). Urine was collect for determining the pH at the same schedule. Higher blood pH was found in cattle infused with all buffers than the chloride infused animals; higher level of blood bicarbonate and base excess were obtained at 4th and 8th h with bicarbonate and L-lactate, as well as with pCO2 at the 8th h. These results show that treatments with B and L lead to a slight accumulation of buffers in the blood, and generate a discrete metabolic alkalosis compensated organically by a small retention of CO2. Best alkalinizing effects are obtained by bicarbonate and L-lactato infusions. Bicarbonate infusions causes a high urinary pH

Uso de bicarbonato e lactato-L para correção da acidose metabólica sistêmica em bovinos com acidose láctica ruminal aguda / Use of bicarbonate and lactate L for correction of systemic metabolic acidosis in cattle with acute rumen lactic acidosis

Foram utilizados seis novilhos, providos de cânula ruminal, em delineamento experimental cross-over, para comparar a eficiência de soluções de bicarbonato de sódio e lactato-L de sódio na correção da acidose metabólica sistêmica (AMS), causada pela acidose láctica ruminal (ALR). Vinte horas após, quando apresentavam intensa AMS, os animais foram distribuídos aleatoriamente e tratados com cinco litros de 150mMol/l de bicarbonato de sódio ou de lactato-L de sódio, infundidas por via intravenosa, nas quatro horas seguintes. Amostras de sangue, para hemogasometria, foram coletadas no decorrer da infusão a zero, 1, 2, 3, 4, 6 e 8 horas. Ambos os tratamentos elevaram o pH sangüíneo já na primeira hora pós-infusão, corrigindo adequadamente a AMS. O tratamento com lactato-L de sódio aumentou as concentrações de bicarbonato, TCO2 e EAB sangüíneos já na segunda hora pós-infusão; com o bicarbonato essa elevação ocorreu a partir da terceira hora. Não houve diferenças entre tratamentos para pH sangüíneo, bicarbonato, TCO2 e excesso de base. Vinte e quatro horas após o tratamento todos os novilhos apresentaram plena recuperação. O lactato-L pode substituir o bicarbonato na correção da AMS em novilhos com ALR

The efficiency of sodium bicarbonate or l-lactate for correcting systemic metabolic acidosis (SMA) caused by rumen lactic acidosis (RLA) was evaluated using six rumen-cannulated steers in a cross-over experimental design. RLA was induced by administration of sucrose, intraruminally. Twenty hours later when the animals developed an intense SMA, the steers were randomly distributed and treated intravenously either with 5l of 15 mMol/l sodium bicarbonate or L-lactate solution, infused throughout 4h. Blood samples were colleted throughout the infusion at zero, 1, 2, 3, 4, 6 and 8h, for blood gas analysis. After 1hour, both sodium bicarbonate and L-lactate solutions increased blood pH and corrected adequately the SMA. Blood bicarbonate, TCO2 and base excess concentrations were also increased at the 2nd hour with L-lactate and at the 3rd hour with bicarbonate. No differences between treatments were observed for blood pH, bicarbonate, TCO2 and base excess concentrations. Treated steers after twenty-four hours showed an effective clinical recovery. L-lactate can adequately replace bicarbonate in the correction of SMA in steers with RLA

Pressão venosa central em bezerros neonatos hígidos / Central venous pressure in healthy newborn calves

Com o propósito de estabelecer valores-padrão da pressão venosa central (PVC), utilizaram-se 24 bezerros sadios, da raça Holandesa, com idade entre oito e 30 dias, e peso entre 37 e 50kg. A PVC foi medida, no átrio direito, com uso de cateter intravenoso e equipo próprio usando-se como via de acesso a veia jugular esquerda. O átrio direito foi considerado o ponto zero de referência para as leituras, estando topograficamente em correspondência externa à articulação escapuloumeral no animal em estação e à região do esterno, quando em decúbito lateral direito. Estabeleceram-se os valores médios da PVC, em centímetros de água, de 0,81±1,40 e 0,88±1,76, respectivamente, nos animais em estação e em decúbito lateral, e não houve diferença estatística entre os valores. A metodologia empregada para mensurar a PVC de bezerros revelou-se segura e exeqüível, não necessitando de aparelhagem sofisticada para a sua determinação.

With the aim of determining the central venous pressure (CVP) standard values, twenty-four healthy Holstein calves, aging 8-to-30 days and weighing from 37 to 50kg, were studied. To measure CVP, a specific intravenous catheter was inserted in the right atrium through the left jugular vein. The right atrium was the reference mark (zero) for the measurements, topographically in external correspondence to the scapulohumeral joint, when the animal was standing; and to the sternum region, when the animal was in right lateral recumbency. It was measured a mean CVP, in centimetres of H2O - 0.81±1.40 for animals in standing position, and 0.88±1.76 for animals in lateral recumbency - with no statistical difference between those values. The technique used for measuring CVP in calves was determined to be feasible and do not require sophisticated devices.

Efeito do tempo após a ingestão de leite sobre o equilíbrio ácido-básico de bezerros / Effect of the time after milk feeding on the acid-base balance of calves

Blood pH, carbon dioxide and oxygen partial pressures, bicarbonate, total carbon dioxide, base excess, standard bicarbonate and oxygen saturation concentrations were measured by blood gas analyses in a study of assessment of the acid-base status in young calves. Venous blood samples were taken from 80 healthy female Holstein calves, from four to 30 days of age. The calves were divided in two groups based on the interval between the morning milk feeding and the blood sample collection (up to 30 minutes or over two hours). Greater alkali reserve and higher carbon dioxide pressure values were observed later than 2h after milk feeding, supporting the influence of the diet on the acid-base balance of calves during the milk feeding phase