German Mendoza | Universidad Autónoma Metropolitana-Xochimilco (original) (raw)
Papers by German Mendoza
Revista MVZ Córdoba, 2014
ABSTRACTObjective. Improve the nutritional value of mechanized sugarcane residues inoculating the... more ABSTRACTObjective. Improve the nutritional value of mechanized sugarcane residues inoculating the fungus Fomes sp. EUM1. Materials and methods. The fungus Fomes was inoculated according to a 0, 0.1, 0.2, and 0.3% (w/v) treatment and incubated at a temperature of 35°C for 7, 10 and 13 days. It was obtained DM, OM, CP, ash, NDF and ADF and the effective degradation of DM, NDF and ADF, with an experimental factorial design of 3X3 and a completely randomized design. The factors were growing days in an Erlenmeyer flask (7, 10, and 13) and inoculum percentage (0.1, 0.2 and 0.3). The data were analyzed with the SAS statistical package. Results. Statistical significance was found in the interaction of the fungus growing days by percentage of inoculum, in the variables: DM, CP and pH. The NDF and ADF factor differed in the percentage of inoculum. Effective degradation showed significant for the same type of interaction in all the variables studied. Conclusions. The inoculation of the fungus ...
Animal Feed Science and Technology, 2000
Production systems of ruminants present dierent eciencies in the use of energy. The transformatio... more Production systems of ruminants present dierent eciencies in the use of energy. The transformations that take place in the process of energy partition in ruminants should be studied in order to reach alternatives of nutritional management that result in a reduction of losses and an increase in the energy retained in usable products. Actions that favour an increase in the digestibility of feed will result in a greater intake of digestible energy. These include an adequate N intake, additives such as exogenous enzymes and some treatments for residues or grains. In order to increase metabolisable energy (ME), it is necessary to reduce energy losses in urine and fermentation gases. For the first, excesses of degradable N compounds in the rumen should be avoided in the diet and the use of ruminally protected amino acids. For the second, the end products of fermentation in accordance with the forage:concentrate ratio and the use of ionophores should be considered. In order to increase net...
Acta Scientiae Veterinariae, 2014
Revista de biologia tropical
Abstract: Forage use and availability for white tailed deer Odocoileus virginianus thomasi (Artio... more Abstract: Forage use and availability for white tailed deer Odocoileus virginianus thomasi (Artiodactyla: Cervidae) in an experimental unit of Campeche, Mexico. In Campeche state, 122 Wildlife Conservation and Management Units have been recently conformed. In these units, eventhough the white tailed deer (Odocoileus virginianus thomasi is a game species, no studies on its diet have been undertaken. The objectives of this work were to estimate the botanical composition of the diet and its seasonal change, to determine forage availability, carrying capacity and stocking rate of O. virginianus thomasi. The study was conducted in the experimental unit of Colegio de Postgraduados in Campeche, Mexico, from October 2010 to May 2012. The diet was determined through microhistological analyses of the white tailed deer feces by the use of reference material. Forage availability was determined through the Adelaide´s method; the stocking rate, using the grazing pressure factor; and carrying capa...
Revista de biología tropical, 2014
Forage use and availability for white tailed deer Odocoileus virginianus thomasi (Artiodactyla: C... more Forage use and availability for white tailed deer Odocoileus virginianus thomasi (Artiodactyla: Cervidae) in an experimental unit of Campeche, Mexico. In Campeche state, 122 Wildlife Conservation and Management Units have been recently conformed. In these units, eventhough the white tailed deer Odocoileus virginianus thomasi is a game species, no studies on its diet have been undertaken. The objectives of this work were to estimate the botanical composition of the diet and its seasonal change, to determine forage availability, carrying capacity and stocking rate of O. virginianus thomasi. The study was conducted in the experimental unit of Colegio de Postgraduados in Campeche, Mexico, from October 2010 to May 2012. The diet was determined through microhistological analyses of the white tailed deer feces by the use of reference material. Forage availability was determined through the Adelaide's method; the stocking rate, using the grazing pressure factor; and carrying capacity co...
Revista de Biología Tropical, 2014
Veterinary Dermatology, 2016
There are few licensed options for the treatment of canine sarcoptic mange. To evaluate the effic... more There are few licensed options for the treatment of canine sarcoptic mange. To evaluate the efficacy of fluralaner in dogs with sarcoptic mange infestation. Seventeen dogs with a diagnosis of Sarcoptes scabiei based on positive skin scrapings. A single dose of oral fluralaner was administered according to the manufacturer's instructions. Assessments of pruritus and lesions were performed every 7 days for 1 month. By Day 14 post-treatment, skin scrapings from all dogs were negative for mites. At the beginning of the study there was a negative correlation between body weight of the subject and pruritus [Pearson correlation coefficient (PCC) = -0.396, P = 0.007] and a positive correlation between pruritus and lesion severity (PCC 0.755, P = 0.0001). Significant decreases in lesion size and pruritus were observed within the first 14-21 days, respectively, and improvement in these parameters continued until the end of the study at Day 28. Fluralaner was effective in eliminating scabies mites within 14 days and significantly resolved the clinical signs associated with sarcoptic mange within 21 days after a single dose.
Tropical Animal Health and Production, 2015
The partial substitution of soybean meal by Gliricidia sepium or Guazuma ulmifolia leaves in the ... more The partial substitution of soybean meal by Gliricidia sepium or Guazuma ulmifolia leaves in the rations of growing lambs was evaluated at an experimental station in the dry tropics of Mexico. Sixteen weaned crossbred male Pelibuey × Blackbelly lambs (initial weight 19 ± 1.66 kg), distributed in a completely randomized design, were assigned to the following protein sources: (a) 100 % soybean meal, (b) 50 % soybean meal + 50 % G. sepium, (c) 50 % soybean meal + 25 % G. ulmifolia + 25 % G. sepium, and (d) 50 % soybean meal + 50 % G. ulmifolia in isoproteic rations. The lambs were housed in individual pens and fed ad libitum. Substitution of protein from soybean meal with G. ulmifolia did not affect gain, intake, or feed conversion; however, the inclusion of G. sepium reduced (linear effect, P < 0.01) gain and intake and impaired feed conversion (linear effect, P < 0.01). Partial substitution up to 50 % of soybean meal with 50 % G. ulmifolia leaves resulted in similar growth and lamb performance, but inclusion of G. sepium leaves adversely affected lamb growth, presumably due to other factors not related to the protein content.
Asian-Australasian Journal of Animal Sciences, 2015
Reproduction in Domestic Animals
Agrociencia
Exogenous fibrolytic enzymes are not synthesized by the ruminal microorganisms, so they are added... more Exogenous fibrolytic enzymes are not synthesized by the ruminal microorganisms, so they are added to feed in order to increase fiber degradation. The objective of this study was to evaluate in vitro xilanase, cellulose and laccase activity, as well as xylanase and cellulose enzymatic stability of an enzymatic fibrolytic product (Fibrozyme Alltech, Inc.). The experimental design was completely randomized and treatments were: buffer pH 6.0, buffer pH 7.0 and clarified ruminal fluid pH 6.5. Data were analyzed using the SAS Mixed procedure and the Tukey test (p≤0.05). The exogenous enzyme product contained 292 IU xylanase g-1 and 36 IU cellulase g-1 , without laccase activity. In buffer with pH 6 cellulases were more stable than the xylanases, and both enzymes showed activity until 46 h. The speed constants of enzymatic inactivation (k) were 0.054 h-1 in xylanases and 0.008 h-1 in cellulases, and half life time (t½) of 12.8 and 87.7 h. In buffer pH 7 cellulases remained more stable a...
Life Science Journal
The objectives of this study were to analyze to assess the progesterone (P 4) and LH concentratio... more The objectives of this study were to analyze to assess the progesterone (P 4) and LH concentrations in response to doses of protected methionine (0, 8, 16, and 24 g d-1) in postpartum dairy cows. A total of 12 cows were used, assigned (n = 3) to each of the doses. From day 15 to day 96 postpartum (four normal estrous cycles), 10 ml of blood was extracted from the jugular vein of each cow to determine concentrations of P 4 , whereas LH samples were obtained on days 14 and 21 of each of the four cycles with an interval of 6 hours 15 min per sample (10:00 to 16:00). The results for the first three cycles showed higher P 4 concentrations (P < 0.05) for the treatment with 16 and 8 and 24 g d-1 ; whereas for the last cycle, there were no differences (P > 0.10) as a consequence, accumulated P4 showed differences higher (P < 0.05) concentration in cows fed 8 and 24 g d-1. The LH concentration or peaks were not affected (P > 0.10) by protected methionine. It was concluded that at...
Abstract Text: Canola seeds have 42-43% EE, 20% CP, and they can be used as a source of protein a... more Abstract Text: Canola seeds have 42-43% EE, 20% CP, and they can be used as a source of protein and energy for ruminants. The objective of this experiment was to evaluate the effect of ground canola grain (GCG) or canola meal (CM) and canola oilseed (CO) added to a concentrate diet (14.59% CP and 2.8 Mcal ME/kg DM) on finishing 21 Pelibuey x Texel lambs (32.09 ± 5.48 kg initial BW) housed in metabolic cages during 42 days. The experimental design was completely randomized with three treatments: T0: 4.6% CM, 67% sorghum grain, 19.5% alfalfa hay; T1: 7.5% GCG, 63.5% sorghum grain, 19.5% alfalfa hay; T2: 4.5% CM, 3% CO, 64% sorghum grain, 19.5% alfalfa hay (all diets contained 5% cornstalk, 2% cane molasses, 1% urea, 1% premix); and seven replications (lambs) per treatment. Variables were average daily gain (ADG, g), daily DM intake (DDMI, g), feed conversion (FC), carcass yield (CY, %) and DM digestibility (DMD, %). Data were analyzed using MIXED procedure (SAS v 9.0) and treatment me...
Journal of animal science, 2003
Eight Holstein steers with cannulas in the rumen and proximal duodenum were used in a split-plot ... more Eight Holstein steers with cannulas in the rumen and proximal duodenum were used in a split-plot design experiment to evaluate the interaction of body weight (175 vs. 370 kg) and level of fat supplementation (0, 3, 6, and 9% yellow grease) on characteristics of digestion and feeding value of fat in finishing diets. Dry matter intake was restricted to 2% of BW. There were no interactions between BW and level of fat supplementation (P > 0.10) on ruminal or total-tract digestion. Level of supplemental fat decreased (linear, P < 0.01) ruminal digestion of OM and NDF, and increased (linear, P < 0.05) ruminal N efficiency. There were no treatment effects (P > 0.10) on postruminal digestion of OM, NDF, and N. There tended to be an interaction (P < 0.10) between BW and level of fat supplementation on postruminal starch digestion. Increasing level of fat supplementation increased postruminal digestion of starch in heavier steers but did not affect starch digestion in lighter s...
Journal of animal science, 1993
Eight ruminally, duodenally, and ileally fistulated sheep were used to study the effects of proto... more Eight ruminally, duodenally, and ileally fistulated sheep were used to study the effects of protozoa on ruminal fermentation and starch digestion in the rumen and intestines. The experimental diet (75% grain DM basis) was based on a mixture of 67% high-moisture corn (HMC) and 33% dry-rolled grain sorghum (DRGS). Protozoa were reduced from 51,286 to 13,987 organisms/mL of ruminal fluid by feeding a diet (13 d) containing 9% tallow and monensin at 27 mg/kg (DM basis). Three sheep were defaunated by intraruminal infusions of lactic acid (20 to 30 g/d) and one sheep by washing the rumen and heating ruminal contents (60 degrees C for 20 min). No differences were observed in DM or starch intake, ruminal fluid pH, lactate concentration, or total tract starch digestibility. Molar proportion of acetate was reduced (48.6 vs 58.3%; P < .01) and propionate was increased (32.2 vs 23.4%; P < .03) by defaunation. Total VFA tended (P = .20) to be lower in faunated sheep (118.5 vs 139.2 mM). I...
Revista MVZ Córdoba, 2014
ABSTRACTObjective. Improve the nutritional value of mechanized sugarcane residues inoculating the... more ABSTRACTObjective. Improve the nutritional value of mechanized sugarcane residues inoculating the fungus Fomes sp. EUM1. Materials and methods. The fungus Fomes was inoculated according to a 0, 0.1, 0.2, and 0.3% (w/v) treatment and incubated at a temperature of 35°C for 7, 10 and 13 days. It was obtained DM, OM, CP, ash, NDF and ADF and the effective degradation of DM, NDF and ADF, with an experimental factorial design of 3X3 and a completely randomized design. The factors were growing days in an Erlenmeyer flask (7, 10, and 13) and inoculum percentage (0.1, 0.2 and 0.3). The data were analyzed with the SAS statistical package. Results. Statistical significance was found in the interaction of the fungus growing days by percentage of inoculum, in the variables: DM, CP and pH. The NDF and ADF factor differed in the percentage of inoculum. Effective degradation showed significant for the same type of interaction in all the variables studied. Conclusions. The inoculation of the fungus ...
Animal Feed Science and Technology, 2000
Production systems of ruminants present dierent eciencies in the use of energy. The transformatio... more Production systems of ruminants present dierent eciencies in the use of energy. The transformations that take place in the process of energy partition in ruminants should be studied in order to reach alternatives of nutritional management that result in a reduction of losses and an increase in the energy retained in usable products. Actions that favour an increase in the digestibility of feed will result in a greater intake of digestible energy. These include an adequate N intake, additives such as exogenous enzymes and some treatments for residues or grains. In order to increase metabolisable energy (ME), it is necessary to reduce energy losses in urine and fermentation gases. For the first, excesses of degradable N compounds in the rumen should be avoided in the diet and the use of ruminally protected amino acids. For the second, the end products of fermentation in accordance with the forage:concentrate ratio and the use of ionophores should be considered. In order to increase net...
Acta Scientiae Veterinariae, 2014
Revista de biologia tropical
Abstract: Forage use and availability for white tailed deer Odocoileus virginianus thomasi (Artio... more Abstract: Forage use and availability for white tailed deer Odocoileus virginianus thomasi (Artiodactyla: Cervidae) in an experimental unit of Campeche, Mexico. In Campeche state, 122 Wildlife Conservation and Management Units have been recently conformed. In these units, eventhough the white tailed deer (Odocoileus virginianus thomasi is a game species, no studies on its diet have been undertaken. The objectives of this work were to estimate the botanical composition of the diet and its seasonal change, to determine forage availability, carrying capacity and stocking rate of O. virginianus thomasi. The study was conducted in the experimental unit of Colegio de Postgraduados in Campeche, Mexico, from October 2010 to May 2012. The diet was determined through microhistological analyses of the white tailed deer feces by the use of reference material. Forage availability was determined through the Adelaide´s method; the stocking rate, using the grazing pressure factor; and carrying capa...
Revista de biología tropical, 2014
Forage use and availability for white tailed deer Odocoileus virginianus thomasi (Artiodactyla: C... more Forage use and availability for white tailed deer Odocoileus virginianus thomasi (Artiodactyla: Cervidae) in an experimental unit of Campeche, Mexico. In Campeche state, 122 Wildlife Conservation and Management Units have been recently conformed. In these units, eventhough the white tailed deer Odocoileus virginianus thomasi is a game species, no studies on its diet have been undertaken. The objectives of this work were to estimate the botanical composition of the diet and its seasonal change, to determine forage availability, carrying capacity and stocking rate of O. virginianus thomasi. The study was conducted in the experimental unit of Colegio de Postgraduados in Campeche, Mexico, from October 2010 to May 2012. The diet was determined through microhistological analyses of the white tailed deer feces by the use of reference material. Forage availability was determined through the Adelaide's method; the stocking rate, using the grazing pressure factor; and carrying capacity co...
Revista de Biología Tropical, 2014
Veterinary Dermatology, 2016
There are few licensed options for the treatment of canine sarcoptic mange. To evaluate the effic... more There are few licensed options for the treatment of canine sarcoptic mange. To evaluate the efficacy of fluralaner in dogs with sarcoptic mange infestation. Seventeen dogs with a diagnosis of Sarcoptes scabiei based on positive skin scrapings. A single dose of oral fluralaner was administered according to the manufacturer&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s instructions. Assessments of pruritus and lesions were performed every 7 days for 1 month. By Day 14 post-treatment, skin scrapings from all dogs were negative for mites. At the beginning of the study there was a negative correlation between body weight of the subject and pruritus [Pearson correlation coefficient (PCC) = -0.396, P = 0.007] and a positive correlation between pruritus and lesion severity (PCC 0.755, P = 0.0001). Significant decreases in lesion size and pruritus were observed within the first 14-21 days, respectively, and improvement in these parameters continued until the end of the study at Day 28. Fluralaner was effective in eliminating scabies mites within 14 days and significantly resolved the clinical signs associated with sarcoptic mange within 21 days after a single dose.
Tropical Animal Health and Production, 2015
The partial substitution of soybean meal by Gliricidia sepium or Guazuma ulmifolia leaves in the ... more The partial substitution of soybean meal by Gliricidia sepium or Guazuma ulmifolia leaves in the rations of growing lambs was evaluated at an experimental station in the dry tropics of Mexico. Sixteen weaned crossbred male Pelibuey × Blackbelly lambs (initial weight 19 ± 1.66 kg), distributed in a completely randomized design, were assigned to the following protein sources: (a) 100 % soybean meal, (b) 50 % soybean meal + 50 % G. sepium, (c) 50 % soybean meal + 25 % G. ulmifolia + 25 % G. sepium, and (d) 50 % soybean meal + 50 % G. ulmifolia in isoproteic rations. The lambs were housed in individual pens and fed ad libitum. Substitution of protein from soybean meal with G. ulmifolia did not affect gain, intake, or feed conversion; however, the inclusion of G. sepium reduced (linear effect, P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.01) gain and intake and impaired feed conversion (linear effect, P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.01). Partial substitution up to 50 % of soybean meal with 50 % G. ulmifolia leaves resulted in similar growth and lamb performance, but inclusion of G. sepium leaves adversely affected lamb growth, presumably due to other factors not related to the protein content.
Asian-Australasian Journal of Animal Sciences, 2015
Reproduction in Domestic Animals
Agrociencia
Exogenous fibrolytic enzymes are not synthesized by the ruminal microorganisms, so they are added... more Exogenous fibrolytic enzymes are not synthesized by the ruminal microorganisms, so they are added to feed in order to increase fiber degradation. The objective of this study was to evaluate in vitro xilanase, cellulose and laccase activity, as well as xylanase and cellulose enzymatic stability of an enzymatic fibrolytic product (Fibrozyme Alltech, Inc.). The experimental design was completely randomized and treatments were: buffer pH 6.0, buffer pH 7.0 and clarified ruminal fluid pH 6.5. Data were analyzed using the SAS Mixed procedure and the Tukey test (p≤0.05). The exogenous enzyme product contained 292 IU xylanase g-1 and 36 IU cellulase g-1 , without laccase activity. In buffer with pH 6 cellulases were more stable than the xylanases, and both enzymes showed activity until 46 h. The speed constants of enzymatic inactivation (k) were 0.054 h-1 in xylanases and 0.008 h-1 in cellulases, and half life time (t½) of 12.8 and 87.7 h. In buffer pH 7 cellulases remained more stable a...
Life Science Journal
The objectives of this study were to analyze to assess the progesterone (P 4) and LH concentratio... more The objectives of this study were to analyze to assess the progesterone (P 4) and LH concentrations in response to doses of protected methionine (0, 8, 16, and 24 g d-1) in postpartum dairy cows. A total of 12 cows were used, assigned (n = 3) to each of the doses. From day 15 to day 96 postpartum (four normal estrous cycles), 10 ml of blood was extracted from the jugular vein of each cow to determine concentrations of P 4 , whereas LH samples were obtained on days 14 and 21 of each of the four cycles with an interval of 6 hours 15 min per sample (10:00 to 16:00). The results for the first three cycles showed higher P 4 concentrations (P < 0.05) for the treatment with 16 and 8 and 24 g d-1 ; whereas for the last cycle, there were no differences (P > 0.10) as a consequence, accumulated P4 showed differences higher (P < 0.05) concentration in cows fed 8 and 24 g d-1. The LH concentration or peaks were not affected (P > 0.10) by protected methionine. It was concluded that at...
Abstract Text: Canola seeds have 42-43% EE, 20% CP, and they can be used as a source of protein a... more Abstract Text: Canola seeds have 42-43% EE, 20% CP, and they can be used as a source of protein and energy for ruminants. The objective of this experiment was to evaluate the effect of ground canola grain (GCG) or canola meal (CM) and canola oilseed (CO) added to a concentrate diet (14.59% CP and 2.8 Mcal ME/kg DM) on finishing 21 Pelibuey x Texel lambs (32.09 ± 5.48 kg initial BW) housed in metabolic cages during 42 days. The experimental design was completely randomized with three treatments: T0: 4.6% CM, 67% sorghum grain, 19.5% alfalfa hay; T1: 7.5% GCG, 63.5% sorghum grain, 19.5% alfalfa hay; T2: 4.5% CM, 3% CO, 64% sorghum grain, 19.5% alfalfa hay (all diets contained 5% cornstalk, 2% cane molasses, 1% urea, 1% premix); and seven replications (lambs) per treatment. Variables were average daily gain (ADG, g), daily DM intake (DDMI, g), feed conversion (FC), carcass yield (CY, %) and DM digestibility (DMD, %). Data were analyzed using MIXED procedure (SAS v 9.0) and treatment me...
Journal of animal science, 2003
Eight Holstein steers with cannulas in the rumen and proximal duodenum were used in a split-plot ... more Eight Holstein steers with cannulas in the rumen and proximal duodenum were used in a split-plot design experiment to evaluate the interaction of body weight (175 vs. 370 kg) and level of fat supplementation (0, 3, 6, and 9% yellow grease) on characteristics of digestion and feeding value of fat in finishing diets. Dry matter intake was restricted to 2% of BW. There were no interactions between BW and level of fat supplementation (P > 0.10) on ruminal or total-tract digestion. Level of supplemental fat decreased (linear, P < 0.01) ruminal digestion of OM and NDF, and increased (linear, P < 0.05) ruminal N efficiency. There were no treatment effects (P > 0.10) on postruminal digestion of OM, NDF, and N. There tended to be an interaction (P < 0.10) between BW and level of fat supplementation on postruminal starch digestion. Increasing level of fat supplementation increased postruminal digestion of starch in heavier steers but did not affect starch digestion in lighter s...
Journal of animal science, 1993
Eight ruminally, duodenally, and ileally fistulated sheep were used to study the effects of proto... more Eight ruminally, duodenally, and ileally fistulated sheep were used to study the effects of protozoa on ruminal fermentation and starch digestion in the rumen and intestines. The experimental diet (75% grain DM basis) was based on a mixture of 67% high-moisture corn (HMC) and 33% dry-rolled grain sorghum (DRGS). Protozoa were reduced from 51,286 to 13,987 organisms/mL of ruminal fluid by feeding a diet (13 d) containing 9% tallow and monensin at 27 mg/kg (DM basis). Three sheep were defaunated by intraruminal infusions of lactic acid (20 to 30 g/d) and one sheep by washing the rumen and heating ruminal contents (60 degrees C for 20 min). No differences were observed in DM or starch intake, ruminal fluid pH, lactate concentration, or total tract starch digestibility. Molar proportion of acetate was reduced (48.6 vs 58.3%; P < .01) and propionate was increased (32.2 vs 23.4%; P < .03) by defaunation. Total VFA tended (P = .20) to be lower in faunated sheep (118.5 vs 139.2 mM). I...