G.D. Mendoza

Is food quality important for carnivores? The case of Puma concolor

The composition and energetic content of puma (Puma concolor) diet in Sierra Nanchititla Natural Reserve (SNNR), Mexico, were determined. We collected 183 scats, where 27 components were identified by occurrence (88.07% mammals). The pumas diet was mainly composed of armadillo (Dasypus novemcinctus, 40.33%), white-nosed coati (Nasua narica, 11.93%) and white-tailed deer (Odocoileus virginianus, 6.17%). Energetic analysis of prey indicates that the puma prefers those with higher energetic content (kcal/kg). The prey with the most energetic contribution is armadillo (2398.70 kcal/kg), followed by white-nosed coati (2225.25 kcal/kg) and finally white-tailed deer (2165.52 kcal/kg). The differences in energetic content between prey species were statistically significant. The number of individuals killed/year on average to support a puma was 51 armadillos, 16 white-tailed deer and 7 white-nosed coatis. The results indicate a greater consumption of prey that provide more kilocalories to the predator, and suggests the importance of quality meat in the diet of pumas.

Hyphal morphology modification in thermal adaptation by the white-rot fungus Fomes sp. EUM1.

A thermotolerant white‐rot fungus was identified as Fomes sp. EUM1. The strain exhibited maximum growth at 30 °C, with activation and inactivation energy values of 68 and 32 kJ/mol, respectively. The temperature affected the hyphal morphology, which was related to the thermotolerance of the microorganism: A shift from 30 to 40 °C in the growth temperature caused a decrease (15%) in mycelium branching; also longer (32%) and thinner (13%) hyphae were produced. In addition, as the temperature rose from 25 to 45 °C, an increase was observed in both the hyphal surface area (43%) and the surface growth rate (193%). The modification of the hyphal morphology suggests a strategy to colonize nutrient‐rich areas while spending minimal energy for biomass formation under thermal stress. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Effects of rumen-protected methionine on milk production of dairy goats

Abstract Twelve lactating Saanen goats were fed with a total mixed ration (forage:concentrate 67:33) and directly supplemented (administered orally) with 0, 2.5 and 5.0g/head/day of rumen-protected methionine (RPM) for 30d. Body weight was not affected by RPM. There were quadratic (P<0.05) effects on milk yield, fact-corrected milk, energy-corrected milk and milk protein as RPM increased; thus, the highest values of milk yield, fact-corrected milk, energy-corrected milk and milk protein were observed with 2.5g of RPM. Percentage of fat increased quadratically (P<0.05) as RPM doses increased, while fat expressed as grams per day was not affected with RPM. It was possible to improve milk production and milk protein in dairy goats with a daily supplemented dose of 2.5g of RPM. Further studies with more animals should be developed.

Nutritional evaluation of cattle manure silage with molasses for ruminants

Abstract Two experiments were conducted to evaluate the nutritional quality of cattle manure silage for ruminants. In experiment 1 a silage containing 50% cattle manure, 20% cane molasses (containing 0.4% urea) mixed with water in a 1:1.5 ratio, and 30% corn stover replaced 0, 50, 75 and 100% of corn stover in isonitrogenous diets (1.92% N) containing 70 or 80% corn stover (dry matter (DM) basis) in a 4×2 factorial arrangement. Forty lambs (34.5±3.2 kg body weight (BW)) were used to measure apparent digestibility and nitrogen balance in a completely randomized design with factorial arrangement (4×2) with five lambs per treatment. The cattle manure silage was also evaluated in growing Holstein heifers (212±32 kg BW) replacing 0, 25 or 37.5% of corn stover with cattle manure silage in isonitrogenous diets (2.24% N). Apparent digestibility of DM, organic matter (OM), neutral detergent fibre (NDF) and acid detergent fibre (ADF) were not affected. According to these results, digestibility is not affected by the level of cattle manure silage; however, intake was depressed at the highest levels of silage in lambs. Cattle manure silage may be considered as a potential by-product to be included in heifers diet up to 37.5%, apparently without affecting performance. Recycling cattle manure through silage for ruminants is a viable alternative.

Influence of fibrolytic enzymes on growth performance and digestion in steers grazing stargrass and supplemented with fermented sugarcane

An experiment was conducted to evaluate the influence of exogenous fibrolytic enzymes on growth performance and digestion in steers grazing stargrass and supplemented with concentrate and sugarcane fermented. Solid state fermentation of sugar cane (SSFSC) was whole sugarcane chopped, added (dry matter basis) with urea (1.5%) and mineral premix (0.5%), and kept under shadow for 24 h. Twenty crossbreed (Brahman × Brown Swiss) steers (287±14.1 kg) grazing stargrass were individually supplemented with SSFSC (free access for 1-h period) and concentrate (1 kg/head) by 100 d. Steer were randomly assigned to concentrate with 0, 15 or 30 g fibrolytic enzyme/kg concentrate. As enzyme level increased, daily gain, intake, digestion, and improved feed conversion were linearly improved.

Effect of Storage Time and Processing Temperature of Grains With Added Amylolytic Enzymes on In situ Ruminal Starch Digestion

Abstract Gutiérrez, C., Mendoza, G.D., Pinos-Rodríguez, J.M., Ricalde, R., Aranda, E. and Miranda, L.A. 2005. Effect of storage time and processing temperature of grains with added amylolytic enzymes on in situ ruminal starch digestion. J. Appl. Anim. Res., 27: 39 Amylolytic exogenous enzymes may increase ruminal digestion of grains. However, stability of enzymes during feed processing can be a constraint for its utilization. Therefore, the objective of this study was to evaluate the efficacy of B. licheniformis amylase and A. niger glucoamylase, according to time of storage after treatment and duration of exposition at 100 C, using corn and sorghum and its effect on in situ ruminal digestibility (12 h incubation) of dry matter and starch. A generalized randomized complete block design was used in the assays, using the block × treatment interaction as the error term. Ruminal starch digestibility (%) was not affected by either time (1, 4, 7, 15 and 30 days) of aspersion before incubation or by the time (0.5, 3, 5, 10 and 15 min) of enzyme exposition at 100 C. It was concluded that both amylolytic thermostable enzymes have the potential as a feed additive to improve ruminal digestibility of corn and sorghum, and are stable at low humidity conditions, which may facilitate its incorporation with grains during feed processing.

Effect of Exogenous Amylase or Glucoamylase Dose on in situ Ruminal Digestion of Corn and Sorghum

Abstract Gutiérrez. C., Mendoza, G.D., Ricalde, R., Melgoza, L.M. and Plata, F. 2005. Effect of exogenous amylase or glucoamylase dose on in situ ruminal digestion of corn and sorghum. J. Appl. Anim. Res., 27: 7–10. Several processes have been developed to increase ruminal digestion of grains. Treatment of grains with exogenous amylase from Bacillus licheniformis and with glucoamylase from Aspergillus niger has increased ruminal digestion. An in situ assay was conducted to determine the effects of the dose of exogenous amylolytic enzymes on in situruminal digestibility (12 h incubation) of corn and sorghum. A complete generalized randomized block design was used, with incubations as blocking criteria. In situ dry matter digestion was increased (P<0.05) with enzyme additions (57.5% control; glucoamylase 75.8%; amylase 82.9%), showing a linear and quadratic effect (P<0.05) of enzyme doses on grain DM digestion. It was concluded that both amylolytic thermostable enzymes have the potential as a feed additive to improve ruminal digestibility of corn and sorghum.

Determination of the jaguar (Panthera onca) and puma (Puma concolor) diet in a tropical forest in San Luis Potosi, Mexico

Jaguar and puma faeces (N=30) were collected in an area of 75 km2 in the tropical forest of Tamasopo in San Luis Potosi. A dot-blot assay was developed with DNA from scats in order to differentiate between jaguar and puma. This assay employed a probe recognising cytochrome b of puma. A total of 14 prey species were found, of which 7 were used by both felids. Jaguar and puma diets in this study showed an overlap of 93.38% where collared peccary was the main prey consumed by both felids (jaguar 39.64% and puma 45.76%). White-tailed deer was also present in the diets of both felids, with a similar biomass consumed (jaguar 7.64% and puma 5.88%). Brocket deer and domestic goat appeared only in the pumas diet. With the exception of some remains from a lizard in the jaguars diet, the rest of the prey species were comprised of medium-sized prey (1–15 kg), with the common opossum and raccoon found for both felids. A method is presented to estimate the number of individuals consumed based on energy requirements. The overlap suggests an important competition between these species.

Use of different kind of silage dairy cattle manure in lamb nutrition

Feeding cattle manure (CM) for ruminants may reduce feed costs for smallholders and provide a partial solution to environment problems for large dairy herds. Feeding value of ensiling CM with molasses (MO), bakery by-products (BBP) and tallow (TW) was evaluated. Five Suffolk male lambs were fed on different kind of CM as follow: i) control: CM and MO; ii) LBBP: CM and low level of BBP; iii) HBBP: CM and high level of BBP; iv) LTW: CM, BBP and low level of TW and v) HTW: CM, BBP and high level of TW. Ensiling CM with BBP had the lowest silage losses. Silages were part of diets, which were fed to lambs fitted with ruminal cannulas. Nutrient intake and N balance did not differ in lambs across all experimental diets, but the NDF digestion of diets with BBP and TW was lower than with MO or BBP. Ensiling CM with BBP offered less silage losses compared with MO.

Influence of Saccharomyces cerevisiae Dose on Ruminal Fermentation and Digestion in Sheep Fed a Corn Stover Diet

Abstract Crosby, M.M., Mendoza, G.D., Bárcena, R., González, S. and Aranda, E. 2004. Influence of Saccharomyces cerevisiae dose on ruminal fermentation and digestion in sheep fed a corn stover diet. J. Appl. Anim. Res., 25: 9–12. A metabolism trial was conducted to evaluate Saccharomyces cerevisiae dose on ruminal fermentation and digestibility. Fourteen Suffolk ewes (35±4 kg BW) with ruminal and duodenal cannula were assigned to a completely randomized design, where treatments were intraruminal dose of microbial culture of Yea-Sacc1026 (0, 1, 3, 5 and 7g/d). Diet was based on corn stover (66.5%), sorghum gram (23.5%), molasses (10.2%) and urea (1.3%). Ruminal pH, VFA concentration, molar proportion of VFA and ammonia-N were not affected by dose. Protozoa population (5.3, 9.6, 11.4, 8.9, 4.0 organisms x 101) showed a quadratic effect (P<0.05) to Saccharomyces cerevisiae dose. Total tract digestibility of DM, NDF and ADF were not affected by treatments. Microbial culture with Saccharomyces cerevisiae at different doses did not improve either fermentation or digestion in sheep fed a com stover diet.