Metabolic profile and histopathology of kidneys and liver of lambs fed silages of forages adapted to a semi-arid environment

Thirty-two mixed-breed ram lambs (average age, 5.6 ± 0.4 months, and average live weight, 17.61 ± 2.63 kg) were used to evaluate the effect of diets containing silages of forages adapted to a semi-arid environment on the metabolic profile in serum and the histopathological assessment of liver and kidney tissues of the lambs. Lambs were allocated, in a completely randomised design, to four treatments (silage of old man saltbush (Atriplex nummularia Lind), buffelgrass (Cenchrus ciliaris), gliricidia (Gliricidia sepium) and ‘pornunça’ (Manihot sp.). The feedlot period was 49 days, and animals were slaughtered at an average weight of 27 ± 4.6 kg. On the last day of the experiment, blood was collected from the jugular vein of all animals to measure the protein, metabolic and energy profiles of the lambs. At slaughter, kidney and liver samples were collected for histopathological examination. The consuming of the diet containing buffelgrass silage resulted in a significantly higher activity of alanine-aminotransferase (30.14 IU/L) and the concentrations of urea (44.25 mg/dL), creatinine (0.94 mg/dL) and albumin (4.48 g/dL) in serum. Diets containing gliricidia silage resulted in significantly higher gamma-glutamyl transferase activity (92.0 IU/L), while the diets with pornunça silage resulted in higher serum levels of triglycerides (37.85 mg/dL). The diets had no effect on aspartate-aminotransferase enzyme activity and total protein, cholesterol and globulin concentrations, or the albumin : globulin ratio in serum. Mild congestion, necrosis and foci of mineralisation were observed in the kidneys of animals fed diets containing old man saltbush (50%) and pornunça (25%) silages, and mild fatty degeneration and mild mononuclear inflammatory infiltrate in their livers. In conclusion, diets containing silages of forages that are adapted to semi-arid environments may be used for feeding lambs, given the absence of dysfunctioning plasmatic levels of liver enzymes and energy and protein profiles. Additionally, kidney failure was not observed in lambs fed these diets during the feedlot period.Keywords: blood parameters, buffelgrass, gliricidia, old man saltbush, pornunç

Characteristics of carcass and non-carcass components of lambs fed diets containing silages of forages adapted to the semi-arid environment

The aim of this study was to evaluate the effects of diets containing silages of forages that are adapted to the semi-arid environment on the characteristics of the carcass and of non-carcass components of 32 mixed-breed lambs at approximately six months old, with an average live weight of 17.61 ± 2.63 kg. Lambs were assigned to four treatments (diets containing silages of Atriplex nummularia Lind, Cenchrus ciliaris, Gliricidia sepium and Manihot sp.) in a completely randomized design with eight replicates. Animals fed the diet containing old man saltbush showed higher values for the intakes of dry matter (1.080 g/day), crude protein (190 g/day) and total digestible nutrients (740 g/day), body condition score (2.81 points), fatness (2.87 points), carcass conformation (3.19 points), live weight (29.1 kg), empty bodyweight (23.41 kg), weights of the commercial cuts neck, shoulder and ribs (0.46, 0.82 and 1.12 kg, respectively), and skin weight (1.972 kg). No differences were found between the diets for carcass dressing percentage, external and internal carcass lengths, leg length and circumference, rump circumference and width, chest width and depth, full bodyweight, empty bodyweight, cooling losses, pH before and after cooling, loin, and leg. Silages of old man saltbush, buffelgrass, gliricidia and pornunça are recommended for inclusion in lamb diets. Diets with old man saltbush silage provide the best results for characteristics of the carcass and of non-carcass components besides weight gain, which can reach up to 200 g/day depending on the formulation.Keywords: Carcass composition, feedlot, saltbush, shee

Fontes de resistência à murcha bacteriana em germoplasma de Capsicum spp. do estado do Amazonas Sources of resistance against bacterial wilt in Capsicum spp. germoplasm of the Amazonas state

A murcha bacteriana, causada por Ralstonia solanacearum, é uma das doenças mais importantes do gênero Capsicum no Brasil. No Amazonas, as condições de elevada temperatura e umidade favorecem o desenvolvimento da doença. O objetivo deste trabalho foi avaliar a resistência à murcha bacteriana de germoplasma, selvagem e comercial, de Capsicum spp. Foram avaliados 22 acessos de Capsicum em casa de vegetação. A inoculação foi feita mediante ferimento das raízes, seguido de adição no solo, ao redor das plantas, de suspensão bacteriana na concentração de 10(8) ufc mL-1. A avaliação foi feita diariamente a partir do quarto dia após a inoculação, em função desenvolvimento dos sintomas. A partir das médias de progresso dos sintomas foi construída a área abaixo da curva de progresso da doença (AACPD), e os dados submetidos ao teste de Scott-Knott ao nível de 5% de probabilidade, utilizando o programa estatístico SAEG 9.1. Foram selecionados os acessos 30, 20 e 17, da espécie C. chinense, como resistentes à murcha bacteriana para ensaios futuros em programas de melhoramento genético.<br>The bacterial wilt caused by Ralstonia solanacearum is one of the most important in the genus Capsicum in Brazil. In the state of Amazonas, high temperatures and humidity favor the development of the disease. The objective of this work was to evaluate resistance in germoplasm of wild and commercial Capsicum spp. to bacterial wilt. Twenty two accesses of Capsicum spp. were evaluated in greenhouse conditions. The inoculation was made by means of wounds in the roots, followed by addition of bacterial suspension in the concentration of 10(8) ufc ml-1 in the soil, around the plants. Plant evaluation was made daily after the fourth day of the inoculation (DAI) considering the symptoms progress. From the average progress of symptoms was constructed the area under the disease progress curve (AUDPC), and the data submitted to the Scott-Knott test at 5% of probability, using SAEG statistical program. From the average severity notes, we constructed the area under the disease progress curve (AUDPC). The accesses 30, 20 and 17 were selected from C. chinense as resistant to the bacterial wilt, for future use in genetic breeding programs

Marcadores microssatélites relacionados com a resistência à vassoura-de-bruxa do cacaueiro Microsatellite markers related to resistance of cocoa tree against witches'-broom

Os objetivos deste trabalho foram caracterizar a resistência à vassoura-de-bruxa de plantas de cacau originadas do cruzamento entre TSH 1188 e CCN 51 (população segregante), por meio de dois métodos de inoculação em condições de campo, e identificar marcadores microssatélites específicos para grupos de plantas resistentes e suscetíveis. As plantas-controle avaliadas pelos métodos de inoculação natural e inoculação artificial em campo produziram os mesmos padrões de sintomas. As plantas da população segregante também coincidiram os padrões de sintomas em 90%, por esses dois métodos. O método de inoculação artificial em campo permite detectar falso-resistentes. Dos 18 pares de primers microssatélites amplificados, 15 foram polimórficos entre os genitores, e seis entre os grupos de plantas segregantes contrastantes quanto à resistência à vassoura-de-bruxa. Foram confirmadas três marcas previamente associadas a QTL (locos para características quantitativas) relacionados com a resistência à vassoura-de-bruxa, comuns a outras populações. Também foram identificados três novos QTL para esta característica, típicos desta população, o que comprova sua utilidade para o melhoramento genético do cacaueiro.<br>The objectives of this work were to evaluate cocoa tree resistance against witches'-broom, in plants originated from the crossing between TSH 1188 and CCN 51 (segregating population), by means of two methods of inoculation in field conditions, and to identify microsatellite markers specific for resistant and susceptible plants. The control plants bore identical symptoms as the plants of the segregating population in 90% of the cases under the two methods. The method of artificial inoculation in the field allows the detection of false resistance to the disease. Of the 18 pairs of microsatellite primers amplified, 15 were polymorphic between genitors and six were polymorphic between the two groups of plants evaluated for resistance to witches'-broom. Three previously characterized markers were confirmed as associated to QTL (quantitative trait loci) related to resistance to the witches'-broom, which is common in other populations. Three new QTL for this characteristic, typical of this population, were also identified, which proves the utility of this population for cocoa breeding