Dwarf and tall elephant grass silages: intake, nutrient digestibility, nitrogen balance, ruminal fermentation, and ingestive behavior in sheep.

The objective of this study was to evaluate the exclusive supply of dwarf or tall elephant grass silages, harvested at 60 days of growth, without wilting or the use of additives, on intake, apparent digestibility, nitrogen balance, rumen parameters, and ingestive behavior of sheep. Eight castrated male crossbred sheep (57.6 ± 5.25 kg body weight), fistulated in the rumen, were distributed in two 4 × 4 Latin squares with four treatments and eight animals per treatment and four periods. The treatments consisted of four elephant grass genotype silages (Mott, Taiwan A-146 2.37, IRI-381, or Elephant B). There was no effect of silages (P > 0.05) on dry matter, neutral detergent fiber, and total digestible nutrient intake. The dwarf-sized elephant grass silages provided higher crude protein intake (P = 0.047) and N intake (P = 0.047), while the IRI-381 genotype silage provided higher non-fibrous carbohydrate intake compared to Mott (P = 0.042), without differing from Taiwan A-146 2.37 and Elephant B silages. There were no differences (P > 0.05) among the digestibility coefficients of the evaluated silages. It was observed that silages produced with Mott and IRI-381 genotypes caused a slight decrease in ruminal pH (P = 0.013), and the propionic acid concentration was higher in the rumen fluid of the animals fed with Mott silage (P = 0.021). Therefore, dwarf or tall elephant grass silages, produced with cut genotypes at 60 days of growth and without the use of additives or wilting process, can be used in sheep feeding.

Physicochemical parameters, fatty acid profile, and sensory attributes of meat from lambs fed with cassava dregs in replacement of corn.

The objective of this study was to evaluate the effect of the replacement of corn by cassava dregs (0, 33, 66, and 100%) in the diet of lamb on physicochemical parameters, fatty acid profile, and sensory attributes of meat. Forty male non-castrated Santa Inês crossbred lambs with an initial average weight of 20 ± 1.87 kg were slaughtered after 70 days. The physicochemical parameters and chemical composition of meat were not affected by the diets. Eicosenoic (C20:1n-9) and linolenic (C18:3n-3) acids increased linearly and there was a linear decreasing effect for the flavor score with increasing cassava dregs in the diets. The replacement of corn by cassava dregs did not influence omega-6:omega-3 ration or the total desirable fatty acids, as well as the color, aroma, tenderness, juiciness, or overall evaluation scores. Cassava dregs may be added in the diets of lambs, without negative effects on physicochemical characteristics, chemical composition, and fatty acid indexes, with positive effects on unsaturated fatty acid content. However, the total replacement of corn altered the sensory attributes and decreased purchase intent of the meat.

Different roughage:concentrate ratios with and without liquid residue of cassava for lambs.

This aim of this study was to evaluate the intake and apparent digestibility of nutrients, ingestive behavior, blood parameters, and performance of lambs fed two roughage:concentrate (R:C) ratios, with or without liquid residue of cassava (LRC). Forty lambs (19.5 ± 1.45 kg body weight) were distributed in a completely randomized 2 × 2 factorial design. The intake of dry matter (1311 g/day) and total digestible nutrients (755 g/day), and the intake (172 g/day) and digestibility (552 g/kg) of crude protein were higher for lambs fed R:C of 40:60. The R:C ratio of 80:20 promoted a higher intake (585 g/day) and digestibility (461 g/kg) of neutral detergent fiber. There was an intake of LRC of 1.37 L/day for lambs fed R:C of 80:20 and 0.42 L/day for lambs fed R:C of 40:60. The lambs fed R:C of 80:20 spent more time in feeding (326 m/day) and rumination (530 m/day). The metabolic profile and performance of lambs were not affected by LRC inclusion. The body weight gain (220 g/day) was higher in lambs fed R:C of 40:60. A roughage:concentrate ratio of 40:60 is recommended for lambs because it resulted in the best performance, regardless of supplementation with liquid residue of cassava.

Sugarcane bagasse as exclusive roughage for dairy cows in smallholder livestock system.

OBJECTIVE: The study aimed to evaluate sugarcane bagasse as roughage in lactating cow on feed intake, digestibility, ingestive behavior, milk production and composition, and microbial protein synthesis. METHODS: Ten Girolando cows at initial body weight of 450±25.6 kg and at 143.7±30.7 days in milk were assigned in two 5×5 Latin square designs. Five 21-day experimental periods were adopted (1° to 14-day: diets adaptation period; 15° to 21-day: data collection and sampling period). The diets consisted of four different levels of sugarcane bagasse (45%, 50%, 55%, and 60%) and a control diet, commonly adopted in the region, based on spineless cactus (25% sugarcane bagasse), formulated to meet 12 kg/d milk yield. RESULTS: The dry matter (DM), organic matter (OM), and total digestible nutrients intakes and DM and OM digestibilities observed for 45% and 50% bagasse inclusion were similar to control diet, while that 55% and 60% bagasse inclusion were lower. Cows fed control diet, and bagasse diets of 45%, and 50% levels had the nutritional requirements attended, that guaranteed 12 kg/d of milk yield. The crude protein intake and digestibility of cows fed 45%, 50%, and 55% of bagasse inclusion were similar to control diet. The neutral detergent fiber (NDF) intake and digestibility differ for all bagasse diets related to control diet, while the non-fiber carbohydrates intake and digestibility for cows fed 45% of bagasse were similar for control diet. The intakes and digestibilities of nutrients decreased linearly in function of bagasse inclusion; NDF and indigestible NDF intakes did not vary. The ruminating time, feeding and rumination efficiency, microbial protein synthesis and milk yield decreased linearly with sugarcane bagasse inclusion. CONCLUSION: Sugarcane bagasse decreases milk production; however, its inclusion level in between 45% to 50% associated to concentrate could replace diets based on spineless cactus for crossbred dairy cow's producing 12 kg/d of milk.

Spineless cactus as a replacement for sugarcane in the diets of finishing lambs.

The effects of replacement of sugarcane by spineless cactus (0, 33, 66, and 100 % on dry matter (DM) basis) were evaluated on intake, digestibility of nutrients, ingestive behavior, and performance of finishing lambs. Thirty-six non-castrated Santa Ines lambs at 4 months of age and an initial body weight of 22 ± 2.3 kg were assigned in a randomized block design. A quadratic effect was found for intake of DM, organic matter (OM), crude protein (CP), neutral detergent fiber (NDF), and digestible organic matter (DOM), with maximum values of 1.31, 1.19, 0.219, 0.358, and 0.845 g/day estimated with 42.5, 38.5, 38.8, 21.3, and 44.9 % replacement level, respectively. The digestibility of DM, OM, CP, and EE increased linearly; however, there was a quadratic effect on NDF digestibility with maximum value estimated of 500 g/kg with 64.2 % replacement level. Rumination time, total chewing, and rumination efficiency decreased linearly with the replacement levels; however, idle time increased linearly. A quadratic effect was found for final weight, body weight gain, and total weight gain with maximum values estimated of 38.6 kg, 0.232 kg/day, and 16.2 kg with 39.1, 38.2, and 40.4 % replacing levels. The replacement of 49.5 % sugarcane by spineless cactus can be recommended as optimal level, and problems related to intake, digestibility, and performance are concentrated outside that level.

Feed handling of lactating crossbred cows maintained in a semi-arid region during the hot season: physiological parameters, ingestive behavior and performance.

The effects of time of feed delivery (14.00 hours; 14.00 and 20.00 hours; 16.00 and 18.00 hours) on the physiological parameters, ingestive behavior, nutrient intake and production of lactating cows maintained in a semi-arid region during the hot season were evaluated. Regardless of treatment, all animals received the first feeding supply at 06.00 hours. Eight cows with an average body weight of 600 kg, average milk yield of 20 kg/day and 80 days in milk were utilized. The rectal temperature, respiratory rate and sweating rate were not affected (P > 0.05), with average values of 38.5°C, 53.8 movements/min and 104 g/m2 /h respectively. There was no effect (P > 0.05) on the eating time (314 min/day), ruminating time (564 min/day), drinking time (61 min/day) and idle time (502 min/day). Similarly, the intake of nutrients and performance of lactating cows were not affected (P > 0.05), with average dry matter intake of 19.8 kg/day, 4% fat-corrected milk of 20.6 kg/day and milk fat concentration of 4.03 g/100 g. Since the behavior and performance have not altered, any times of feed delivery evaluated could be used to crossbred Holstein × Zebu cows maintained on a feedlot in semi-arid regions during the hot season.

Effect of water hyacinth (Eichhornia crassipes) hay inclusion in the diets of sheep.

The aim of this study was to evaluate the effects of replacing Tifton-85 hay (0, 20, 40, 60 and 80 % on a dry matter basis) with water hyacinth hay (Eichhornia crassipes) on intake and digestibility of nutrients, feeding behaviour, rumen and blood parameters of sheep. Five uncastrated male sheep, cannulated in the rumen, with an average body weight of 40 kg were assigned in a 5 × 5 Latin square design. The water hyacinth hay contained 870 g/kg dry matter (DM), 159 g/kg crude protein (CP), 547 g/kg neutral detergent fibre (NDF) and 461 g/kg total digestible nutrients (TDN). The DM intake and digestibility of NDF and non-fibre carbohydrates (NFC) were linearly reduced by replacing the Tifton-85 hay with water hyacinth hay. Similarly, there was a linear reduction of rumination time and efficiencies of feeding and rumination of DM and NDF. The concentrations of urea, glucose, AST and GGT in blood plasma were not changed by replacing the Tifton-85 hay with water hyacinth hay. Although water hyacinth hay reduced the intake and digestibility of some nutrients, the Tifton-85 hay replacement could be economically advantageous for sheep feeding.

Origins of sample mistakes in the measure of the length and weight of fish larvae - DOI: 10.4025/actascibiolsci.v30i3.393 / Fontes de erros na mensuração do comprimento e peso de larvas de peixes - DOI: 10.4025/actascibiolsci.v30i3.393

Experiments in the cultivation or ecological with fish larvae, invariably use the length and weight with parameters. Therefore, this experiment was accomplished with larvae of Lophiosilurus alexandri pacamã aiming at to determine some sources of mistakes sampling in the measurement of the size and of the weight of fish larvae. It was evaluated five possible sources of mistakes then. The first was the mistake in the measure of the lengths total and standard, due sharpness of two observers" measurement. The second the mistake in the measure of the lengths total and standard, due to the proportionate shrink for the fixative formomalin to 10%. The third party was the mistake due two forms of drying of the larvae in the obtaining of the biomass. The fourth experiment was on the influence of the size and of the grouping of the larvas in the obtaining of weights. Finally the last tested the alteration of the biomass due to the time of permanence of the larvae in the balance. The importance can be verified of to determine and to accomplish an sampling protocol for measurements of fish larvae. For they present size and weight reduced, a small variation in the condition of the mensure, it can alter the result significantly, because significant alterations were verified above for the tests referred.

Trabalhos com larvas de peixes, sejam de cultivo ou ecológicos invariavelmente empregam o comprimento e o peso como parâmetros. Assim sendo, este experimento foi realizado com larvas de Lophiosilurus alexandri pacamã objetivando determinar algumas fontes de erros amostrais na medição do tamanho e do peso de larvas de peixes. Avaliou-se cinco possíveis fontes de erros. O primeiro foi o erro na medida dos comprimentos total e padrão, devido a acuidade de medição de dois observadores. O segundo, foi o erro na medida dos comprimentos total e padrão, devido ao encolhimento proporcionado pelo fixador formalina a 10%. O terceiro foi o erro devido a duas formas de secagem das larvas na obtenção da biomassa. O quarto experimento foi sobre a influência do tamanho e do agrupamento das larvas na obtenção de pesos. Por fim, o quinto teste observou a alteração da biomassa devido ao tempo de permanência das larvas na balança. Pôde-se verificar a importância de se determinar e cumprir um protocolo de amostagem para medições de larvas de peixes. Por apresentarem tamanho e peso reduzidos, uma pequena variação na condição da mensuração, pode alterar substancialmente o resultado, pois alterações significativas foram verificadas para os testes acima referidos.