Effects of cold stress on physiologic metabolism in the initial phase and performance of broiler rearing.

This study aimed to investigate the effects of 8 h of cold stress (18 °C) every day in broiler chicks during the first 7 days of rearing on crop filling analysis, yolk sac consumption, digestive and immune organs weights, and physiological metabolism at seven days and performance between 1 and 35 days. Cobb500 male broiler chickens (n = 274) were randomly assigned to two treatments. The treatments consisted of varying environmental temperatures during the first week post-housing. Chicks were reared at a thermoneutral temperature (32 °C) or under cold stress (18 °C) for 8 h/day during the first week, and both groups were subsequently reared at a thermoneutral temperature for 8-35 days. The thermoneutral group reached 90% full crop after 48 h of housing (P < 0.05), while the cold-stressed group had more empty crops at 2 h and 48 h after housing (P < 0.05). The chick cloacal temperature was not affected by the treatments (P > 0.05). Additionally, the treatment did not affect serum amylase and corticosterone levels, feed intake, body weight gain, or feed conversion ratio (P > 0.05, while the cold-stressed group had elevated heterophil/lymphocyte count at day 7 (P < 0.05). The thermoneutral group showed higher viability (%) at 7 and 35 days and a higher production factor at 35 days (P < 0.05). Broiler chickens under cyclic cold stress experienced decreased yolk sac absorption during the first week and increased feed intake and feed conversion ratio after 35 days of rearing. Viability was also lower in the cold-stressed group. An appropriate strategy to minimize these adverse effects is to rear the chicks in a thermoneutral environment during the first week.

Effects of total parenteral nutrition associated with glutamine, enteral fluid therapy with or without glutamine, and fluid therapy on the acid-base and electrolyte balance of horses starved after exploratory laparotomy.

This study aimed to evaluate the effects of the total parenteral nutrition associated with glutamine, enteral fluid therapy with or without glutamine, and fluid therapy on the acid-base and electrolyte balance of horses starved after exploratory laparotomy. Sixteen healthy male and female adult horses of mixed breed, aged between 4 and 14 years, and having a mean body weight of 248.40 ± 2.28 kg and a body score index of 3-4 (scale of 1-5) were divided into four groups with four animals per group. After an adaptation period of 30 days, they were randomly divided into four experimental groups: enteral fluid therapy, enteral fluid therapy associated with glutamine, total parenteral nutrition associated with glutamine, and parenteral fluid therapy. The experiment was further divided into two phases: Phase 1 and Phase 2. In Phase 1, an exploratory laparotomy was performed, treatments were administered to the groups and the horses received no food or water other than those given to their respective groups. In Phase 2, the animals were re-fed. Each phase had a total duration of 144 h. Venous blood samples were collected every 24 h throughout the experimental period for blood gas and electrolyte analyses. The following parameters were evaluated: pH, partial pressure of carbon dioxide, total carbon dioxide, bicarbonate, base shift, anion gap, sodium, potassium, chloride, total calcium and magnesium. Completely randomized designs with a 4 × 7 factorial scheme (groups × harvest time) in Phase 1 and a 4 × 6 factorial scheme (groups × harvest time) in Phase 2 were used with four replications. All values were considered significant when p≤0.05 (95% probability). Blood pH, bicarbonate concentration, and base shift in the PARGL group decreased, indicating metabolic acidosis. Changes in the acid-base and electrolyte balance were more intense in the PARGL group than in the other groups. These results demonstrated the need to monitor blood gas and electrolyte balance in horses with food restriction under nutritional support or prolonged fluid therapy so that such changes are promptly corrected.

Este estudo teve como objetivo avaliar os efeitos da nutrição parenteral total associada à glutamina, fluidoterapia enteral com ou sem glutamina e fluidoterapia no equilíbrio ácido-base e eletrolítico de equinos submetidos à inanição após laparotomia exploratória. Dezesseis cavalos adultos saudáveis, machos e fêmeas, sem raça definida, com idade entre 4 e 14 anos, com peso corporal médio de 248,40 ± 2,28 kg e índice de escore corporal de 3 a 4 (escala de 1 a 5) foram divididos em quatro grupos com quatro animais por grupo. Após um período de adaptação de 30 dias, foram divididos aleatoriamente em quatro grupos experimentais: fluidoterapia enteral, fluidoterapia enteral associada à glutamina, nutrição parenteral total associada à glutamina e fluidoterapia parenteral. O experimento foi ainda dividido em duas fases: Fase 1 e Fase 2. Na Fase 1, os tratamentos foram administrados aos grupos, a laparotomia exploratória foi realizada e os cavalos não receberam alimentos ou água além daqueles dados aos seus respectivos grupos. Na Fase 2, os animais foram realimentados. Cada fase teve uma duração total de 144 h. Amostras de sangue venoso foram coletadas a cada 24 h durante todo o período experimental para análises gasométricas e eletrolíticas. Foram avaliados os seguintes parâmetros: pH, pressão parcial de dióxido de carbono, dióxido de carbono total, bicarbonato, desvio de base, anion gap, sódio, potássio, cloreto, cálcio total e magnésio. Delineamentos inteiramente casualizados com esquema fatorial 4 × 7 (grupos × época de colheita) na Fase 1 e esquema fatorial 4 × 6 (grupos × época de colheita) na Fase 2 foram utilizados com quatro repetições. Todos os valores foram considerados significativos quando p≤0,05 (95% de probabilidade). O pH sanguíneo, a concentração de bicarbonato e o desvio de base no grupo PARGL diminuíram, indicando acidose metabólica. As alterações no equilíbrio ácido-base e eletrolítico foram mais intensas no grupo PARGL do que nos outros grupos. Esses resultados demonstraram a necessidade de monitorar o equilíbrio hemogasométrico e eletrolítico em equinos com restrição alimentar sob suporte nutricional ou fluidoterapia prolongada para que tais alterações sejam prontamente corrigidas.

Current Diagnostic Methods for Assessing Transfer of Passive Immunity in Calves and Possible Improvements: A Literature Review.

Several direct or indirect methods can be used to assess immunoglobulin G (IgG) concentrations in calves, which evaluates the transfer of passive immunity (TPI). Radial immunodiffusion (RID) is the gold standard method to measure serum IgG in bovines. Previous studies have shown that colostrum provides several molecules in addition to immunoglobulins, which play an important role in the passive immunity of the calf. However, no studies have yet determined the level of interference of these components in the immunity, health and survival of calves. In this sense, the objective of this study is to review the methods of evaluation available for the laboratory and field diagnosis of TPI in calves and discuss the main aspects of each technique. Several methods available for TPI evaluation in calves may provide insights into the various components of colostrum involved in passive immunity.

Influence of Stretching Exercises, Warm-Up, or Cool-Down on the Physical Performance of Mangalarga Marchador Horses.

The Horse Agribusiness Complex is an important activity in the Brazilian agricultural sector. Mangalarga Marchador (MM) is the most numerous breed of horses in Brazil and its temperament and gait characteristics (4-beat stepping gait) allow for the constant growth of the breed and the performance of vs. equestrian activities. The training management currently adopted with MM horses is based on empiricism, and scientific support is necessary to improve the well-being of horses in competitions and maintain the physical integrity of these athletes. Therefore, this study aimed to verify the effects of stretching, warming up, and/or cooling down on their performance in marcha tests. 6 MM geldings (aged between 3 and 7 years and average weight of 400 kg) were used. The pre-experimental stage for the physical conditioning of the horses lasted 46 days. The experimental phase lasted 42 days and consisted of 6 marcha tests performed every 7 days. The experimental design was in a Latin square (6 × 6), in which each horse was submitted to the following exercise protocols: A) 50-min marcha test following the official regulations of the Brazilian Association of Horse Breeders Mangalarga Marchador (ABCCMM); B) 10 min of warm-up before marcha test; C) 10 min of cooling after marcha test; D) 10 min of warm-up before marcha and 10 min of cool-down after marcha test; E) 10 min of stretching before the marcha test; F) 10 min of stretching, 10 min of warm-up before and 10 min of cool-down after the test. Horses were evaluated before and after marcha tests for heart rate (HR), respiratory rate, rectal temperature, glucose, lactate, creatine kinase, aspartate aminotransferase and cortisol. Data were submitted to 2-way analysis of variance (exercise protocols and evaluation moments) and means were compared by Tukey's test (P≤0.05). The HR and blood lactate results indicated a beneficial effect of warm-up or stretching practices on the performance of Mangalarga Marchador horses submitted to simulated marcha tests in accordance with the official ABCCMM regulation and lasting 50 minutes.

Effects of Equine Chorionic Gonadotropin on Ovulatory and Luteal Characteristics of Mares Submitted to an P4-Based Protocol of Ovulation Induction With hCG.

The aim of this study was to evaluate the effect of equine chorionic gonadotropin (eCG) at the end of progesterone (P4) treatment on follicular and luteal characteristics during transition period (TP) and reproductive breeding season (RP). A total of 13 crossbred mares were distributed in two experimental groups in the spring and summer (n = 26). The animals received intravaginal P4 (1.9 g) releasing device from D0 to D10. On removal of P4 device, the mares received 400 IU of eCG (eCG group) or saline solution (control group). Human chorionic gonadotropin (hCG; 1.750 IU) was administered (DhCG) as soon as ovulatory follicle (OF) ≥35 mm was detected. Ovarian ultrasonography was performed from D0 until 15 days after ovulation. Blood samples were collected on D0, D5, D10, DhCG, 9 days after ovulation (CL9D), and 13 days after ovulation (CL13D). P4 and estradiol concentrations were assessed by chemiluminescence. Data were compared by Tukey test at P < .05. Ovulation rate was similar (P = .096) between seasons (RP = 100%; TP = 70%) but occurred earlier (P = .015) in RP (34.8 ± 10.1 hours) compared with TP (42.0 ± 10.4 hours). Interactions between season and treatment were observed for OF diameter (mm) (RP/control = 36.2 ± 1.8ab; RP/eCG = 32.9 ± 2.8 b; TP/control = 32.2 ± 1.2 b; TP/eCG = 37.2 ± 1.9a; P = .004) and for corpus luteum (CL) diameter (mm) on CL13D (RP/control = 25.4 ± 3.5a; RP/eCG = 22.5 ± 1.8ab; TP/control = 21.6 ± 4.9 b; TP/eCG = 27.4 ± 4.3a; P = .023), although no differences were observed for serum P4 on CL13D (RP/control = 6.0 ± 3.1 ng/mL; RP/eCG = 5.8 ± 0.9 ng/mL; TP/control = 3.6 ± 2.7 ng/mL; TP/eCG = 5.1 ± 2.3 ng/mL; P = .429) or for day of structural CL regression (RP/control = 12.8 ± 1.9; RP/eCG = 12.1 ± 1.1; TP/control = 11.0 ± 1.7; TP/eCG = 13.2 ± 2.0; P = .102). The application of eCG at the moment of P4 implant removal seemed to increase the capacity of luteal maintenance during spring TP. However, eCG treatment was worthless during the breeding season.

Daily rhythms of leukocytes populations, biochemical and enzymatic blood parameters in a carnivorous freshwater catfish (Lophiosilurus alexandri).

The aim of this study was to investigate the daily rhythms of hematological, biochemical and enzymatic parameters of the blood of a nocturnal model of fish (Lophiosilurus alexandri) bred in the laboratory (F1). Thirty-six juveniles were stocked in six tanks of a recirculation aquaculture system for 20 days. The fish were exposed to a light:dark cycle of 12:12 h and were fed 1% of biomass twice a day with commercial diet. The daily rhythms of hematological, biochemical and enzymatic parameters were then measured at six sampling times "zeitgeber time = ZT" at four-hour intervals under light:dark 12:12 h (lights on = ZT0, at 8.00 a.m). No differences were observed to alkaline phosphatase, glucose, cortisol, aspartate aminotransferase, superoxide dismutase, total protein and hematocrit (p > 0.05). However, white blood cell count, Lymphocytes (LYN), Neutrophils (NEU), Eosinophil and Neutrophils to Lymphocytes ratio were significant different between sample times (p < 0.05). Also, a significant difference in alanine transaminase was observed, with a peak of production at nighttime. In contrast, glutathione peroxidase peaked at 8:00. Uric acid, magnesium and Calcium (Ca++) showed statistically significant differences (p < 0.05). A significant difference was observed (p < 0.05), with a peak of albumin at 08:00 and triglycerides at 12:00, while cholesterol was low (p < 0.05) at 08:00 and higher from 12:00 to 04:00. Cosinor analysis revealed also rhythmicity to SOD, UA, Mg and Ca++, ALB and CHO (p < 0.05). In conclusion, the time of day must be considered a key factor when using blood parameters as biomarkers for disease, health and welfare in the L. alexandri aquaculture.

Serological, molecular, and microscopic detection of Leishmania in cats (Felis catus) in Belo Horizonte, Minas Gerais State, Brazil / Detecção sorológica, molecular e microscópica de Leishmania em gatos (Felis catus) em Belo Horizonte, Minas Gerais, Brasil

Abstract The role of cats in the epidemiological cycle of leishmaniasis remains unclear. To better understand the occurrence of leishmaniasis in cats, we studied the frequency of Leishmania in serum samples of 100 cats living in an endemic region for canine and human leishmaniasis by serological, parasitological, and molecular methods. Of the 100 cats, 54 were seropositive for Leishmania antibodies by immunofluorescence antibody test. None of the bone marrow aspirates collected from these cats tested positive for the parasite in culture or upon polymerase chain reaction (PCR) analysis. Biopsy samples of the ears also tested negative for Leishmania upon PCR analysis. These findings may indicate that the region is endemic for canine leishmaniasis and cats are infected by Leishmania; or that cross-reaction with antibodies against other parasites increases the frequency of seropositivity; or that cats respond to Leishmania infection by producing antibodies when few or no parasites are present in bone marrow and tissue samples. Overall, our results suggest that cats can be infected by Leishmania ; however, we failed to demonstrate feline parasitosis. These findings highlight the need to study leishmaniasis in cats, since sandflies feed on cats, these animals may act as a reservoir for the parasite.

Resumo O papel dos gatos no ciclo epidemiológico da leishmaniose ainda não está claro. Para entender melhor a ocorrência de leishmaniose em gatos, estudou-se a frequência de Leishmania em amostras de soro de 100 gatos, os quais vivem em uma região endêmica para leishmaniose canina e humana, por métodos sorológicos, parasitológicos e moleculares. Dos 100 gatos, 54 foram soropositivos para anticorpos de Leishmania por teste de anticorpos de imunofluorescência. Nenhum dos aspirados de medula óssea coletados desses gatos mostrou-se positivo para o parasita em cultura, ou após a realização da reação em cadeia da polimerase (PCR). Amostras de biópsia das orelhas também foram negativas para Leishmania submetidas a PCR. Esses achados indicam que na região estudada endêmica para leishmaniose canina, os gatos podem se infectar por Leishmania; ou que a reação cruzada com anticorpos contra outros parasitas aumenta a frequência de soropositividade; ou que os gatos respondem à infecção por Leishmania produzindo anticorpos quando poucos ou nenhum parasita estão presentes na medula óssea e em amostras de tecido. Em geral, os resultados sugerem que os gatos podem ser estar infectados por Leishmania spp. No entanto, não foi possível demonstrar parasitismo felino. Essas descobertas evidenciam a necessidade de estudar a leishmaniose em gatos, uma vez que, como os flebotomíneos se alimentam em gatos, e esses animais podem atuar como um reservatório para o parasita.

Serological, molecular, and microscopic detection of Leishmania in cats (Felis catus) in Belo Horizonte, Minas Gerais State, Brazil.

The role of cats in the epidemiological cycle of leishmaniasis remains unclear. To better understand the occurrence of leishmaniasis in cats, we studied the frequency of Leishmania in serum samples of 100 cats living in an endemic region for canine and human leishmaniasis by serological, parasitological, and molecular methods. Of the 100 cats, 54 were seropositive for Leishmania antibodies by immunofluorescence antibody test. None of the bone marrow aspirates collected from these cats tested positive for the parasite in culture or upon polymerase chain reaction (PCR) analysis. Biopsy samples of the ears also tested negative for Leishmania upon PCR analysis. These findings may indicate that the region is endemic for canine leishmaniasis and cats are infected by Leishmania; or that cross-reaction with antibodies against other parasites increases the frequency of seropositivity; or that cats respond to Leishmania infection by producing antibodies when few or no parasites are present in bone marrow and tissue samples. Overall, our results suggest that cats can be infected by Leishmania ; however, we failed to demonstrate feline parasitosis. These findings highlight the need to study leishmaniasis in cats, since sandflies feed on cats, these animals may act as a reservoir for the parasite.

Avaliação da acurácia de dois glicosímetros veterinários para uso em cães / Accuracy evaluation of two veterinary glucometers for use in dogs

Os glicosímetros (GT) são estratégia importante para mensuração da glicemia. Devem estar dentro das especificações da ISO 15197:2013 e avaliados pela análise da grade de erros. Objetivou-se avaliar a acurácia de dois glicosímetros veterinários (GT1 e GT2), pela comparação dos valores de glicemia mensurados em sangue capilar, com aqueles fornecidos por métodos laboratoriais de referência em amostras plasmáticas, transformadas ou não em valores de plasma equivalente. Na avaliação de GT1 em amostras de sangue capilar e o método laboratorial hexoquinase obtiveram-se média das diferenças de 25,90 mg/dL e 26 % das amostras recaíram sobre os limites propostos pela ISO15197: 2013. A comparação de GT1 aos valores de glicemia estimados para plasma equivalente, mostrou média de diferenças de 10,89 mg/dL e 99 % das amostras atenderam aos limites pretendidos. Comparações avaliação de GT2 e o método laboratorial glicose oxidase em amostras de sangue total capilar, a média das diferenças foi 10,58 mg/dL e 22 % das amostras atenderam aos intervalos propostos pela ISO15197: 2013; quando avaliado pela glicemia estimada para plasma equivalente, a média das diferenças foi de 9,7029 mg/dL e 99% das amostras atenderam aos limites. Quando avaliados pela grade de erros de erros, 87% das amostras avaliadas por GT1 recaíram sobre as zonas de erros A e B e aquelas avaliadas por GT2 apresentaram 86% das amostras sobre tais zonas. Os glicosímetros avaliados não apresentaram a acurácia para mensuração da glicemia capilar conforme os padrões expostos pela normativa ISO 15197:2013.

The glucometers (GT) are important strategy for measuring blood glucose. They must be within the specifications of ISO 15197: 2013 and evaluated by analysis of the error grid. The objective of this study was to evaluate the accuracy of two veterinary glucometers (GT1 and GT2) by comparing the blood glucose values measured in capillary blood with those provided by reference laboratory method in plasma samples, transformed or not at equivalent plasma values. In the evaluation of GT1 in capillary blood samples and the hexokinase laboratory method, the mean differences were 25.90 mg / dL and 26% of the samples fell within the limits proposed by ISO 15197: 2013. The comparison of GT1 to the estimated plasma glucose values showed a mean difference of 10.89 mg / dL and 99% of the samples were in the desired limits. Comparisons of GT2 and laboratory glucose oxidase in capillary blood samples, mean differences were 10.58 mg / dL and 22% of the samples met the ranges proposed by ISO; 15197: 2013. When evaluated by the estimated plasma glucose, the mean differences were 9.7029 mg / dL and 99% of the samples met the limits. When evaluated by the error grid, 87% of the samples evaluated by GT1 fell on the zones of errors A and B and those evaluated by GT2 presented 86% of the samples on such zones. The glucometers evaluated did not present the accuracy to measure capillary glycaemia according to the standards set in ISO 15197: 2013.

Antifeeding and short-term insecticidal effects against Lutzomya longipalpis in dogs treated with permethrin or deltamethrin / Efeitos não alimentação e inseticida em curto prazo sobre Lutzomyia longipalpis em cães tratados com permetrina ou deltametrina

Canine visceral leishmaniasis is a zoonotic disease caused by parasites of the genus Leishmania and transmitted by phlebotomine sandflies of the genus Lutzomyia in the New World and Phlebotomus in the Old World. The individual protection of dogs by treatment with permethrin 65% or by a 4% deltamethrin-impregnated collar is evaluated in this study based on the antifeeding of the products and the short term insecticidal antifeeding effects in the following sites on the dog's body: the inner side of the ear and the inguinal region. Both products produced a decrease in blood feeding and an increase in the antifeeding of the sandflies and the effects were not homogeneous, as there were significant differences between the effects on the pinna and on the inguinal region. The treatments of dogs with synthetic pyrethroids are important strategies to reduce the infection rates in endemic regions however the antifeeding and antifeeding effects were low and may not be sufficient to ensure a dog's individual protection.

Leishmaniose visceral canina é uma zoonose causada por parasitos do gênero Leishmania e transmitida por flebótomos do gênero Lutzomyia no Novo Mundo e Phlebotomus no Velho Mundo. A proteção individual do cão através do tratamento com produtos contendo permetrina 65% ou com a coleira impregnada com deltametrina 4% é avaliada no presente estudo, baseado nos efeitos de não alimetação e inseticida imediatos no pavilhão auditivo direito e região inguinal direita. Ambos os produtos demonstraram redução no ingurgitamento das fêmeas e aumento da mortalidade, mas o efeito não foi homogêneo, uma vez que foram verificadas diferenças estatisticamente significativas nos efeitos nas diferentes regiões. O tratamento dos cães com piretroides é uma importante estratégia para redução das taxas de infecção em regiões endêmicas, no entanto, os efeitos mortalidade e repelência foram baixos e podem não ser suficientes para a proteção individual do cão.

Leucograma de eqüinos hígidos submetidos a um protocolo hemodialítico / Leokogram in healthy horses submitted to a hemodialysis protocol

Com o objetivo de realizar adequação da técnica de hemodiálise para a espécie eqüina, foram formados quatro grupos experimentais de seis animais cada, sendo os tratamentos: Grupo I: animais submetidos a cateterismo central unilateral e protocolo de sedação (controle); Grupo II: animais submetidos a cateterismo central unilateral com cateter duplo-lúmen e uma sessão de hemodiálise de seis horas; Grupo III: animais submetidos a cateterismo central unilateral com cateter duplo-lúmen e duas sessões de hemodiálise de seis horas; Grupo IV: animais submetidos a cateterismo central bilateral com cateter mono-lúmen e uma sessão de hemodiálise de seis horas. Empregou-se xilazina 10 por cento (0,4 mg/kg) associada a acepromazina 2 por cento (0,08 mg/kg) via intravenosa para sedação. Foram utilizados dois hemodialisadores em série, do tipo fibras ocas, e o fluxo sanguíneo foi de 319,18 ± 97,41 mL/minuto. A anticoagulação foi feita com heparina sódica em 100 UI/kg para primming, repetida na dose de 53,86 ± 18,61 UI/kg/hora. Dentre as respostas pesquisadas neste estudo, na avaliação hematológica não foram observadas alterações do leucograma (contagem global e diferencial dos leucócitos e avaliação da morfologia celular). Concluiu-se que a técnica de hemodiálise pode ser empregada na espécie eqüina, utilizando-se dialisadores de polissulfona, com tempo de seis horas em cada sessão de diálise, sem causar alterações hematológicas no leucograma.

With the goal of promote hemodialysis technical adequacy for horses, four experimental groups with six animals was formed, and the folowing treatments was applied: Group I: horses submited to unilateral central venous catheter and a sedation protocol (control group); Group II: horses submited to unilateral central venous double lumen catheter and one session of six hours hemodialysis; Group III: horses submited to unilateral central venous double lumen catheter and two sessions of six hours hemodialysis; Group IV: horses submited to bilateral central venous mono lumen catheter and one in session of six hours hemodialysis. Xilazine 10 percent (0,1 ml/50 kg) associated with acepromazine 2 percent (0,1 ml/50 kg) was done by venous rote for sedation. Two hollow fiber, low flux polyssulfone of 1,8m2 was used in serie connexion. The mean blood flux was 319,18 ± 97,41 ml/min. Antiocoagulation was performed with sodium heparin, 100 UI/kg for primming and at the dose of 53,86 ± 18,61 UI/kg/hr. For the evaluation performed in this study, in the blood analysis was not observed leukogram alterations (global and differential leukocytes counts and celular morphology evaluation). Was concluded that hemodialysis can be applied for horses by using polyssulfone dializers in six hours dialysis session, without leading hematological.