Effects of Sodium Monensin on Copper Metabolism of Brazilian Santa Inês Sheep Submitted to Different Dietary Copper.

This study aimed to evaluate the influence of sodium monensin on the hepatic accumulation of copper in sheep. Twenty-four Santa Inês crossbred sheep were used and allocated in a 2 × 2 factorial experiment with six repetitions and considering the factors dietary copper (basal and high) and supplementation (with and without sodium monensin). Thus, four homogeneous groups were formed: control (basal diet); monensin (Mon), 30 ppm of monensin; copper (Cu), 10 10 mg/kg BW per day of copper; monensin + copper (MonCu). The experimental period lasted 14 weeks. Liver and bile samples were collected at the beginning and end of the experiment to determine mineral element concentrations, and weekly blood samples for biochemical, hematological, and mineral evaluation. Liver copper concentrations at the beginning of the experiment did not vary between groups, while mean liver copper concentrations at the end of the experiment were higher in the MonCu, Cu, and Mon groups when compared to the control. At the end of the study, hepatic copper concentration was influenced by copper (p = 0.0001) and monensin (p = 0.0003) supplementation. Copper-supplemented groups had reduced liver iron contents (p = 0.0287) and increased copper concentrations in bile. The biochemical evaluation showed increased serum GGT and AST activity (p < 0.05) in the Cu and MonCu groups from the eleventh week on compared to the control and Mon groups. The increase in activity of these enzymes was influenced by copper supplementation (p = 0.0340). Monensin interferes positively with the hepatic accumulation of copper and the supplementation of this additive may predispose sheep to copper poisoning.

Kidney changes in lambs fed cactus pear varieties resistant to Dactylopius opuntiae as the only roughage.

This study aimed to evaluate the effects of four varieties of cactus pear resistant to carmine cochineal as exclusive roughage for lambs on the biochemical, histopathological, and histomorphometric parameters of kidneys. Twenty-four castrated male crossbred lambs at eight months of age and an initial body weight of 21.0 ± 0.5 kg were distributed in a completely randomized design, with four treatments and six repetitions. The experimental treatments consisted of four diets containing Miúda cactus pear, IPA-Sertânia cactus pear, IPA-F21 cactus pear, or Orelha de Elefante Mexicana (OEM) cactus pear as the only roughage. Blood samples were collected every two weeks (14 d, 28 d, 42 d, and 56 d) to quantify serum urea and creatinine levels. After 72 days of the introduction of the tested diets, the animals were slaughtered and fragments of the kidneys were collected for histological analysis. The serum urea level was higher in animals fed a diet based on the Miúda variety (49.38 mg dL-1), and the serum creatinine levels were lower in the last two collections (P = 0.009). The most frequent histopathological findings in the kidneys were calcification, congestion, glomerular atrophy, presence of luminal cellular debris, and nephrosis, regardless of the cactus pear variety. The Miúda cactus pear and OEM cactus pear varieties caused more severe damage to the nephron components, while the varieties IPA F-21 and IPA-Sertânia caused less significant injuries. The use of IPA-Sertânia and IPA F-21 cactus pear varieties is suggested in lamb's diets, due to the lower impact on the renal parenchyma. However, there was no expressive impairment of renal function, and there was no difference between the cactus pear varieties tested in this study on the weight gain of the animals, and they can all be used to feed feedlot sheep.

Assessment of Donkey (Equus asinus africanus) Whole Blood Stored in CPDA-1 and CPD/SAG-M Blood Bags.

Hemotherapy using whole blood and its components is being increasingly used in veterinary therapy. Since it is important to store animal blood while maintaining acceptable hematological, blood gas, and biochemical characteristics, increasing our knowledge of available technologies for strategic blood storage is imperative. Thus, we aimed to assess the hematological, blood gas, and biochemical changes in donkey whole blood using blood bags with two different types of storage agents. Eight adult healthy male donkeys were used; 900 mL of blood was collected from each, with 450 mL stored in citrate-phosphate-dextrose and adenine bags (CPDA-1) and 450 mL stored in bags containing citrate-phosphate-dextrose, adenine, mannitol, and sodium chloride (CPD/SAG-M). Both bags were kept refrigerated between 1 and 6 °C for 42 days. Blood samples were removed from the bags eight times (T): T0 (immediately after blood collection), T1, T3, T7, T14, T21, T35, and T42 (1, 3, 7, 14, 21, 35 and 42 days after storage). Hematological, blood gas, biochemical, and microbiological parameters were assessed. The CPDA-1 bags had a higher packed cell volume when compared to CPD/ SAG-M. The red blood cell count reduced by around 19% in both the bags due to hemolysis, which was confirmed by an increase in plasma hemoglobin. The white blood cell count; pH; concentrations of glucose, sodium, bicarbonate, and 2,3 diphosphoglycerate were reduced in both bags. Meanwhile, pO2, pCO2, lactate dehydrogenase, and levels of potassium increased in the CPDA-1 and CPD/SAG-M bags. Blood bags were efficient for the storage of donkey blood for up to 42 days.

Validation of a handheld ß-hydroxybutyrate acid meter to identify hyperketonaemia in ewes.

BACKGROUND: The end of pregnancy is the period with the highest risk of occurrences of ketosis and pregnancy toxemia due to fat mobilization and increasing non-esterified fatty acids in the liver which are converted in ketone bodies, mainly ß-hydroxybutyrate acid (BHB). This ketone body may also become elevated in the bloodstream. The present study validates the use of a handheld meter for determining the blood concentration of BHB and ascertaining the predictive value and accuracy of BHB measurements in diagnosing hyperketonaemia in ewes. METHODS: A total of 19, non-pregnant, crossbred ewes were subjected to 2 h of intravenous infusion of a saturated BHB solution. Over 6 h of evaluation, 247 blood samples were obtained in 13 sampling moments. The BHB concentration was measured by an enzymatic colorimetric method in an automated biochemical analyzer (gold-standard) and by a handheld meter using an electrochemical enzyme technique. RESULTS: There was a high correlation between both methods (r = 0.98; P < 0.001). Considering the blood BHB concentrations range 0.8-1.6 mmol/L for moderate ketosis the handheld meter presented sensitivity and specificity of 0.98 and 0.81, respectively. For severe ketosis (BHB ≥ 1.6 mmol/L) sensitivity and specificity were 0.99 and 0.75, respectively. Thus, the handheld device can be useful for diagnoses of cases of mild or severe pregnancy toxemia at field conditions.

Dietary Zinc Supplementation to Prevent Chronic Copper Poisoning in Sheep.

The aim of this study was to evaluate whether zinc (Zn) supplementation protects against hepatic copper (Cu) accumulation in copper-loaded sheep. Forty cross-bred lambs were assigned to five experimental groups. These included the control group (C) and four treatment groups that received Cu and/or Zn supplementation (dry matter (DM) basis) over 14 weeks, as follows: Cu (450 mg Cu/kg); Zn-35 (450 mg Cu + 35 mg Zn/kg); Zn-150 (450 mg Cu + 150 mg Zn/kg); and Zn-300 (450 mg Cu + 300 mg Zn/kg). Blood, liver, and bile samples were obtained for mineral determination by inductively coupled plasma optical emission spectrometry (ICP⁻OES). The hepatic metallothionein (MT) concentrations were also determined. At the end of the experiment, hepatic Cu concentrations were higher in all Cu-supplemented groups than in C. Hepatic Cu accumulation was lower in the groups receiving the Zn supplementation than in the Cu group, although the difference was only statistically significant (66%) in the Zn-300 group. The MT concentrations tended to be higher (almost two-fold) in the Zn groups (but were not dose related) than in the C and Cu groups, and they were related to hepatic Zn concentrations. Zn supplementation at 300 mg/kg DM is useful for preventing excessive hepatic Cu accumulation in sheep exposed to high dietary concentrations of Cu.

Comparative assessment of probiotics and monensin in the prophylaxis of acute ruminal lactic acidosis in sheep.

BACKGROUND: Acute ruminal lactic acidosis (ARLA) is a major nutritional and metabolic disorder usually characterized by excessive or non-adapted intake of diets rich in nonstructural carbohydrates. Feed additives that regulate the ruminal environment have been used to prevent ARLA, such as ionophores and, more recently, yeast culture. Thus, we aimed to compare the efficacy of a yeast-based culture (Saccharomyces cerevisiae) with that of monensin sodium in the prevention of ARLA in sheep. Eighteen male, crossbred, rumen-cannulated sheep were randomly distributed into three groups of six animals: control, yeast culture and monensin. Thirty days after the start of supplementation with yeast culture (4 × 109 cfu/animal/day of S. cerevisiae) and monensin (33 mg/kg of total dry matter intake), 15 g/kg BW of sucrose was administered directly into the rumen of the animals to induce ARLA. Samples of blood and ruminal fluid were collected at the following time points: at baseline (T0 h) immediately before the induction of ARLA; 6 h (T6 h); 12 h (T12 h); 18 h (T18 h); 24 h (T24 h); 36 h (T36 h); and 48 h (T48 h) after ARLA induction. RESULTS: Ruminal pH was higher in monensin group at T12 h and in yeast culture group at T36 h when compared to control group. Lower values of L-Lactate were found at yeast culture group at T24 h and T36 h. Monensin showed prophylactic effect by decreasing the rate of ruminal pH decline and occasionally reducing ruminal acidosis, whereas probiotics resulted in less accumulation of lactic acid in the rumen and a lower degree of systemic acidosis. CONCLUSION: The use of yeast culture can be beneficial in the prevention and treatment of ARLA in sheep, because it can effectively reduce the accumulation of lactic acid, and thereby increase ruminal pH and reduce ruminal osmolarity. On the other hand, monensin showed prophylactic effect by decreasing the rate of ruminal pH decline and occasionally reducing ruminal acidosis, however, it did not directly prevent these conditions.

Effects of sudden melon intake on ruminal parameters of non-adapted sheep / Efeitos da ingestão súbita de melão sobre os parâmetros ruminais de ovinos não adaptados

This study evaluated the effects of varying amounts of melon with high sugar content offered to sheep without prior melon experience and that were not adapted to consuming it. We used 12 eight-month-old, rumen-cannulated crossbred sheep weighing 25 kg each. The animals received a base diet of roughage, and then half were randomly selected to have 25% of their diet replaced with melon (G25%) and the other half had 75% of their diet replaced with melon (75%). Ruminal fluid was collected before administration of melon and at 0, 3, 6, 12, 18, and 24 h after the administration of the fruit. Sheep from the G25% group presented volatile fatty acid ruminal acidosis (sub-acute) between 3 and 6 h after consumption. This acidosis was characterized by a rumen pH slightly lower than 5.6, increased discrete L-lactic acid content, and increased redox potential (RP) and methylene blue redox (MBR) time of the ruminal fluid. The G75% group presented lactic ruminal acidosis at T6h, characterized by a rumen pH lower than 5.0, high lactate-L content, increased RP and MBR time, and increased ruminal fluid osmolarity. Therefore, offering large amounts of melon (75% of dry matter (DM)) is not recommended but 25% of DM of this fruit can be used safely.

O presente estudo avaliou o efeito da adição à dieta de duas diferentes quantidades de melão com alto teor de açucares oferecidos subitamente à ovinos não adaptados. Foram utilizados 12 ovinos mestiços da raça Santa Inês, com 8 meses de idade e pesando cerca der 25 kg providos de cânula ruminal. Os animais recebiam dieta à base de volumoso e foram aleatoriamente divididos em dois grupos iguais que receberam 25 ou 75% de adição de melão picado à dieta. Foram coletadas amostras de conteúdo ruminal nos momentos zero e após 3, 6, 12, 18, e 24 horas da administração do melão. Ovinos do grupo G25% apresentaram acidose por ácido graxo voláteis (subaguda) entre 3 e 6 horas, caracterizada por pH ruminal ligeiramente abaixo de 5,6, aumento discreto na concentração de ácido láctico L e aumento do potencial redox (PR) e tempo de redução do azul de metileno (TRAM) do fluido ruminal. O grupo G75% apresentou acidose láctica ruminal com pH menor que 5,0, alta concentração de Lactato-L e aumento do PR e TRAM e da osmolaridade ruminal. Em conclusão, o oferecimento de grandes quantidades de melão (75% da MS) não é recomendado, mas 25% da MS desta fruta pode ser utilizada na dieta de ovinos com segurança.

Clinical response and transfusion reactions of sheep subjected to single homologous blood transfusion.

Studies in relation to blood conservation and responses to transfusion are scarce for ruminants. We evaluated the clinical manifestations of sheep that received a single homologous transfusion of whole blood, focusing on transfusion reactions. Eighteen adult sheep were subjected to a single phlebotomy to withdraw 40% of the total blood volume, which was placed into CPDA-1 bags and then divided into G0, animals that received fresh blood, and G15 and G35, animals that received blood stored for 15 or 35 days, respectively. Clinical observations were recorded throughout the transfusion, whereas heart rate, respiratory rate, and rectal temperature were assessed at the following times: 24 hours after phlebotomy and before transfusion; 30 minutes, six, twelve, 24, 48, 72, and 96 hours and eight and 16 days after transfusion. All groups presented transfusion reactions, among which hyperthermia was the most frequent (50% of animals). Tachycardia occurred most frequently in the G35 animals (50% of them). During transfusion G35 animals presented more clinical manifestation (P < 0.05). Transfusion of fresh or stored total blood improved the blood volume, but transfusion reactions occurred, demonstrating that a single transfusion of fresh or stored blood can cause inflammatory and febrile nonhemolytic transfusion reactions in sheep.

Influência de diferentes dietas com alto teor de concentrados sobre parâmetros ruminais, bioquímicos e urinários de ovinos / Effects of different diets with high content of concentrates on ruminal, biochemical and urinary parameters of sheep

Oito ovinos, da raça Santa Inês, receberam dieta controle (C) (80% de feno de capim coast-cross e 20% de concentrado comercial) e em seguida foram submetidos a experimento em quadrado latino com dietas contendo 30% desse feno e 70% dos concentrados: polpa cítrica peletizada (PCP); polpa cítrica farelada (PCF); fubá de milho (FM) e farelo de trigo (FT). Depois de 21 dias de adaptação às dietas, foi realizada monitoração visual por 24 h. No dia subsequente à observa-ção, na terceira hora após a alimentação, foram coletadas amostras de conteúdo ruminal, urina e sangue. No conteúdo ruminal foi determinado o pH, nas amostras de urina foram efetuadas análises de pH, ureia, fósforo, creatinina e exame de sedimento, e no sangue foram realizadas determinações séricas de ureia, fósforo e creatinina. Foram calculados o indice de excreção urinária (IEUP) e a taxa de excreção fracional (TEFP) de fósforo. Os dados foram avaliados por análise de variância e Teste de Tukey ou Mann-Whitney. Foi realizada a análise de correlação entre pares de variáveis. Tanto a PCP como a PCF estimularam significativamente a ruminação semelhante ao grupo controle, e com maior rempo que o FM (P<5,05). Maiores concentrações de P sérico, IEUP e TEFP foram encontradas na dieta FT (P<5,05). Quanto maiores os teores de P sérico maior o IEUP (r-0,78). Quanto maior o tempo devotado à ruminação menor foi o fósforo sanguineo (r=0,62). A maior ruminação diminuiu os teores de fósforo sérico e sua excreção urinária, diminuindo assim a predisposição à urolitíase em ovinos.

Eight adult Santa Inês sheep received a control diet (C) (80% of coast-cross hay and 20% of commercial feed) and then they were submitted to a Latin square experiment with diets containing 30% of hay and 70% of the following concentrates: pelleted citrus pulp (PCP), citrus pulp meal (PCF), cornmeal (FM) or wheat bran (FT). After 21 days of adaptation to the diets visual monitoring was performed for 24 h. On the day after the visual observation samples of rumen content, urine and blood were taken at the 3rd hour after feeding. Rumen content was analyzed for pH; urine samples were analyzed for pH, urea, phosphorus, creatinine and sediment examination. Blood samples were used for serum determinations of urea, creatinine and phosphorus. The index of urinary excretion of phosphorus (IEUP) and fractional excretion rate of phosphorus (TEFP) were calculated. Data were evaluated by analysis of variance and Tukey test or Mann-Whitney test. Pearson correlation analysis was made to compare variables. Both the PCP and PCF significantly stimulated rumination, similar to the control group, being higher when compared with the FM diet. Increased concentrations of serum P, IEUP and TEFP were found in the FT diet (P < 0.05). The higher the serum levels of P, the higher the P excretion in the urine (r = 0.78). The higher the time devoted to rumination, the lower the serum P concentrations (r2 = 0.62). The increased rumination decreased the serum P and its urinary excretion, reducing the predisposition to urolithiasis in sheep.

Clinical evaluation of nervous ketosis induced by isopropanol in sheep / Manifestações clínicas da cetose nervosa induzida por isopropanol em ovinos

Twelve healthy Santa Ines sheep, non-pregnant and non-lactating underwent a protocol of experimental induction of nervous ketosis for studying the symptoms in ketosis and Pregnancy Toxaemia (PT) disease. Eight animals were subjected to infusion of 150 mL of isopropanol (IPA) at 35% in the jugular vein and four sheep were treated identically with isotonic saline solution (NaCl 0.9%) during 40 minutes. The animals treated with IPA showed increased heart rate (HR) after 40 minutes of infusion and decreased ruminal movement from the 10 minutes infusion with IPA and remaining low up to 10 minutes from the end of the infusion. Ruminal atony appeared in three animals, which showed slight meteorism gas. Infusion of IPA caused the appearance of nervous symptoms as depression, staggering, adduction of hind limbs, head pressing, teeth grind and blindness almost always accompanied by a decreased pupillary reflex and nystagmus. All the animals exhaled ketosis breath with strong odor within few minutes of the start of induction that helped the elimination of the IPA from the organism. The present results strongly suggest that part of the nervous symptoms observed in PT may be derived from the action of IPA. These present findings open new perspectives for a better understanding of the pathogenesis of PT in sheep...

Doze ovelhas hígidas, não prenhes e não lactentes foram submetidas a um protocolo de indução experimental de cetose nervosa para a avaliação de sintomatologia nos quadros de cetose e Toxemia da Prenhez. Neste protocolo, oito animais foram submetidos a infusão de 150 mL de solução de isopropanol a 35% na veia jugular, constituindo o grupo Tratado (GT), e quatro ovinos foram tratados identicamente com solução salina isotônica (NaCl 0,9%), constituindo o grupo Controle (GC) no decorrer de 40 minutos. Os animais do GT apresentaram aumento da frequência cardíaca (FC) aos 40 minutos de infusão e redução no movimento ruminal a partir dos 10 minutos de infusão com isopropanol, o qual permaneceu diminuído ate 10 minutos do termino da infusão. A atonia ruminal ocorreu em três animais, que manifestaram em seguida leve meteorismo gasoso. A infusão de isopropanol provocou o surgimento de sintomas nervosos como, depressão e sonolência, cambaleios, adução de membros posteriores, pressão da cabeça em obstáculo, ranger de dentes e cegueira quase sempre acompanhada de diminuição do reflexo pupilar e nistagmo. Todos os animais exalaram forte odor cetótico com poucos minutos do inicio da indução, fato que ajudou a eliminação do isopropanol do organismo. Os presentes resultados sugerem que parte dos sintomas nervosos verificados na Toxemia da Prenhez possa ser oriunda da ação do isopropanol. Estes resultados abrem novas perspectivas para o melhor entendimento da patogenia da Toxemia da Prenhez em ovinos...

Copper deficiency in sheep with high liver iron accumulation.

An outbreak of enzootic ataxia among sheep raised in the northeastern region of Brazil is described. Copper (Cu) deficiency was diagnosed in a herd of 56 sheep, among which five presented characteristic clinical symptoms of enzootic ataxia. The symptoms began 30 days after birth, with a clinical condition that included locomotion difficulty, limb ataxia, tremors, and continual falls. Liver biopsies were performed and blood was collected to determine hepatic and plasmatic Cu, iron (Fe), and zinc (Zn) concentration, respectively. The laboratory results showed that the animals presented low copper concentrations in the plasma and liver, without difference between the clinically healthy animals and those affected by enzootic ataxia. Even after supplementation with adequate Cu levels had been recommended, it was found on a new visit to the farm four months later that one animal still presented a clinical condition and that the hepatic Cu levels of the herd had not risen. Despite the low copper content of the diet, the high hepatic Fe levels found suggest that antagonism due to this element may have been an important factor in triggering copper deficiency in these animals, and thus, additional copper supplementation may be necessary for these animals.

Avaliação clínica do uso de solução salina hipertônica no tratamento da acidose láctica ruminal aguda em bovinos / Clinical evaluation of hypertonic saline solution treatment for acute ruminal lactic acidosis on cattle

A infusão de solução salina hipertônica (SSH) é um importante tratamento em animais com choque hipovolêmico. Bovinos com acidose láctica ruminal aguda (ALRA) frequentemente apresentam quadros de desidratação. Este trabalho avaliou a eficiência do tratamento da ALRA com SSH. Foram empregados 12 bovinos machos, mestiços com um ano de idade. Após implantação de cânula ruminal e período de adaptação alimentar os animais foram submetidos à indução de ALRA por meio de administração de sacarose no rúmen. Após 20 horas da indução, os animais foram aleatoriamente divididos em dois grupos. Um deles (SSH) foi tratado na 20ª h com 5 mL/kg P.V. de uma solução de SSH (7,5 % NaCl), dentro de 15 min, e em seguida 20 mL/kg/P.V. de solução salina isotônica (SSI), no decorrer dos próximos 165 minutos. O outro grupo (SSI) foi medicado da mesma forma, com exceção da SSH que foi substituído por 5 mL/kg PV de SSI. Cinco litros de conteúdo ruminal foram retirados, sendo repostos com cinco litros de água em ambos os grupos. Variáveis foram mensuradas no momento 0 (MO), na 20ª h (M20h) e no decorrer dos tratamentos (M30´, M60´, M120´ e M180´). O uso de SSH provocou, nos primeiros 30 minutos, uma ligeira acidemia, acompanhada de discreta hipercapnia, contudo sem provocar efeitos colaterais. A infusão de SSH provocou uma queda no volume globular, confirmando a migração de fluidos do rúmen para a circulação, corrigindo parcialmente a desidratação. Assim, o uso de SSH é uma possibilidade de tratamento adicional da desidratação provocada pela ALRA.

Hypertonic saline solution (HSS) is known as an important treatment for hypovolemic shock. Cattle with acute rumen lactic acidosis (ARLA) usually present different degrees of dehydration. This study evaluated the efficiency of HSS for treatment of ARLA. Twelve yearling, cross-bred, male cattle were used. After an adaptation period, when a rumen cannula was implanted, the animals were submitted to an induction of ARLA by the administration of sucrose into the rumen. Twenty hours later the cattle were randomly divided in two groups. The 1st group was treated with 5 mL/kg BW with 7.5 % (NaCl), within 15 min after 20th h of the induction; thereafter it was infused 20 mL/ kg BW of isotonic saline solution (ISS) for the next 165 min. The 2nd group was treated only with ISS. Five liters of ruminal contents were removed and replaced with five liters of water in both groups. Variables were measured at time 0 (MO), 20 h (M20h) and throughout the treatment (M30´, M60´, M120´ e M180´). The use of HSS caused a mild acidemia followed by a discrete hypercapnia. No side effects were seen in cattle treated with HSS. Infusion of HSS decreased the globular volume indicating a passage of fluids from the rumen into the bloodstream, correcting partially the dehydration. The use of HHS is a possible additional treatment for correction of dehydration caused by ARLA.