Simple SummarySheep are susceptible to copper toxicosis, a deadly disease that usually occurs when the animals ingest large amounts of this mineral. Considering that the susceptibility of sheep to copper accumulation varies widely among breeds and from animal to animal., we evaluate whether Zn supplementation could be an option as a preventive measure to protect against hepatic Cu accumulation in sheep. Zn at 300 mg/kg dry matter (DM) is useful for preventing excessive hepatic Cu accumulation. Hepatic Cu accumulation is lower in animals receiving the Zn supplementation.AbstractThe 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.

BackgroundAcute 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.ResultsRuminal 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.ConclusionThe 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.

The response to blood loss is directly related to the degree of hemorrhage, but for the caprine species some aspects still need to be investigated. Therefore, the present study aimed to assess the clinical and hemodynamic effects of acute blood loss in goats. Eight healthy, adult male crossbred goats were subjected to external jugular puncture to remove 30% of the total blood volume. A physical examination and blood gas, biochemical, and hematologic analyses were performed at baseline, before blood loss (T0), and after one (T1h), six (T6h), 12 (T12h), 24 (T24h) and 72 (T72h) hours, and eight (T8d), 16 (T16d), 24 (T24d) and 32 (T32d) days after the acute blood loss event. The goats presented with tachycardia, tachypnea, and hyperthermia one hour after blood loss with a return to normal physiological values at T6h. Packed cell volume was decreased at T1h and red cell counts at T12h, both returning to baseline at T24d. There was a reduction in total protein and albumin levels at T1h, both remained below baseline levels until T16d and T8d, respectively. The serum calcium concentration decreased over the period T1h to T24h and glucose increased over the period T1h to T6h. The values of pH, TCO 2 , bicarbonate, and base excess were lower at T1h, while lactate increased markedly at this time. The pCO 2 value only was reduced at T24h. Systolic (PS), diastolic (PD), and mean (PM) pressures were decreased at T1h. Acute loss of 30% of blood volume in goats caused changes in clinical, blood gas, and biochemical parameters, which were restored over a six-hour period, while hematologic changes were more persistent, with baseline values restored only after 24 days. Key words: Shock. Blood gas. Hypovolemia. Blood. ResumoA resposta clínica à perda de sangue está diretamente relacionada ao grau de hemorragia, mas para a espécie caprinas alguns aspectos ainda precisam ser investigados. Deste modo o presente estudo teve como objetivo avaliar os efeitos clínicos e hemodinâmicos da perda aguda de sangue em caprinos. Oito caprinos adultos, mestiços, hígidos, foram submetidas a punção jugular externa para remoção de 30% do volume total de sangue. Foi realizado exame clínico e análises hematológicas, hemogasométricas e bioquímicas no momento basal, antes da perda de sangue (T0), e uma (T1h), seis (T6h), 12 (T12h), 24 (T24h) e 72 (T72h) horas e oito (T8d), 16 (T16d), 24 (T24d) e 32 (T32d) dias após. As cabras apresentaram taquicardia, taquipneia e hipertermia uma hora após a perda de sangue com retorno aos valores fisiológicos em T6h. O volume globular diminuiu em T1h e a contagem de células vermelhas em T12h, ambos retornando valores basais em T24d. Houve uma redução nos níveis de proteína totais e albumina em T1h, e ambos permaneceram abaixo dos níveis basais até T16d e T8d, respectivamente. A concentração sérica de cálcio diminuiu durante o período T1h para T24h e a glicose aumentou no período T1h a T6h. Os valores de pH, TCO2, bicarbonato e excesso de base foram menores em T1h, enquanto o lactato aumentou acentuadamente neste...

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RESUMO.-[Efeitos da ingestão súbita de melão sobre os parâmetros ruminais de ovinos não adaptados.] O presente estudo avaliou o efeito da adição à dieta de duas diferentes quantidades de melão com alto teor de açuca-res 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. 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.