In Vitro Gas Production and Dry Matter Degradability of Diets Consumed by Goats with or Without Copper and Zinc Supplementation

An in vitro gas production technique was used to evaluate the effects of copper and zinc supplementation on the amount and rate of gas production, dry matter degradability (IVDMD), utilization of metabolizable energy (ME), and ruminal fermentation patterns using rumen fluid from four Boermale goats as inoculum. The goats were fed twice daily at 07:00 and 19:00 h a total mixed ration containing 10.3 and 22.5 mg/kg DM of Cu and Zn, respectively. This diet was incubated in vitro for 96 h with four treatments being: control, Cu (21.7), Zn (5.6), and Cu–Zn (21.7 and 5.6) which was provided as a mineral premix. Data were analyzed as a completely randomized design. Rates of gas production (RGP) at 4 (RGP4h) and 6 h (RGP6h) and gas production (GP) at 24 (GP24h) and 48 h (GP48h) differed (p<0.01) among treatments. An addition of Cu increased the RGP4h, RGP6h, GP24h, and GP48h (p<0.0001). The Cu treatment had the highest IVDMD and control the lowest (p<0.05), and the Cu treatment was the highest values of ME and SCFA. The addition of Cu to the in vitro ruminal fermentation increased gas production and efficiency of energy use

Ovulatory and embryonic response to recombinant bovine somatotropin in goats super ovulated with FSHp

Artículo científico publicado en revista indizada.El objetivo del estudio fue evaluar el efecto de la somatotropina bovina recombinante (rBST) en la actividad ovárica, cantidad y calidad de embriones transferibles en cabras durante el anestro estacional. Se utilizaron 30 cabras multíparas sincronizadas con protocolo corto de CIDR y superovuladas con FSHp, asignadas a tres tratamientos (n = 10): T1 = control, sin rBST, T2 = 100 mg rBST y T3 = 200 mg rBST. Las variables cuantitativas se analizaron mediante prueba de Kruskal-Wallis; el porcentaje de estro y de embriones recuperados, mediante prueba de Chi - cuadrada. Las cabras del T3 tuvieron mayor número de CL, seguidas del T2 (p = 0.002). El número de embriones recuperados y de blastocitos fue mayor en T3 (p = 0.001). El número de mórulas fue mayor en T1 (p = 0.001). La aplicación de rBST al inicio del estro incrementa la actividad ovárica y la cantidad de embriones transferibles en cabras

Influence of individual or mixed cellulase and xylanase mixture on in vitro rumen gas production kinetics of total mixed rations with different maize silage and concentrate ratios

Cellulase, xylanase, and β-D glucanase enzymes are specific for the breaking of internal β-1,4 linkages of cellulose, hemicellulose (xylan), and glucans to release soluble sugars and facilitate the growth of microbes, thereby increasing the in vitro dry matter (DM) digestibility (8). Morgavi et al. (7) demonstrated the synergism between exogenous and endogenous rumen enzymes such that the net combined hydrolytic effect in the rumen was much higher than that estimated from individual enzyme activities. Exogenous enzymes may be applied during ensiling or directly fed to animals during feeding (1). Enzyme application during ensiling gives an economical benefit to farmers by increasing the feed intake (i.e. palatability) and digestion rate (1,9). Direct addition of enzymes to animal feeds just before feeding is much easier and more applicable in terms of agronomic practices.This study assessed the effects of cellulase, xylanase, and their mixture (1:1, v/v) on in vitro rumen fermentation of five mixed rations with different maize silage (F) to concentrate (C) ratios (0F:100C, 25F:75C, 50F:50C, 75F:25C, 100F:0C). Samples were incubated using rumen inoculum from Brown Swiss cows fed ad libitum a total mixed ration of concentrate and alfalfa hay (1:1). Gas production (GP) was recorded after 2, 4, 6, 8, 10, 12, 24, 36, 48, and 72 h of incubation. Interaction effects (P < 0.0001) were observed between type of ration and enzyme for discrete lag time prior to GP. Ration type affected asymptotic GP (linear and quadratic, P < 0.0001) and in vitro GP at 24 h onward. Moreover, rations affected pH (linear and quadratic, P < 0.0001), dry matter degradability (quadratic, P = 0.05), metabolizable energy (linear, P = 0.038), short-chain fatty acids (linear, P = 0.0005), gas yield from truly digested dry matter at 24 h (linear, P = 0.0026), and microbial crude protein yield (linear, P = 0.0264). The most effective rations for in vitro GP during different times differed between different measured parameters. Enzyme administration was more effective when the ratio of maize silage was increased

Influence of Exogenous Enzymes on In Vitro Gas Production Kinetics and Dry Matter Degradability of a High Concentrate Diet

This study was conducted to evaluate the influence of an exogenous enzyme mixture on in vitro gas production (GP), in vitro dry matter degradability (DMD), metabolizable energy (ME) and short chain fatty acid (SCFA) production in growing lambs fed a high concentrate diet. ZADO® (ENZ) is a powdered, commercially available multi-enzyme feed additive produced from Ruminococcus flavefaciens. Four levels of ENZ (i.e., 0, 5, 10 and 20 mg/g DM; or EO, E5, E10 and E20, respectively) were applied directly to the substrate inside the incubation bottles before addition of buffer medium and rumen fluid, and the treatments were assayed in triplicate runs. Addition of ENZ linearly increased (P<0.05) GP at 6 and 96 h of incubation and tended (P=0.08) to linearly increase GP at 12, 48 and 72 h of incubation. Asymptotic GP was increased linearly (P=0.05) as the level of ENZ increased and the lag time decreased linearly (P=0.003). Concurrently, DMD increased linearly (P<0.001) as the level of ENZ increased, but level of ENZ had no effect on SCFA and ME. Finally, level of ENZ had no influence on rate of gas production. Results suggest that this enzyme preparation has potential to improve efficiency of utilization of high concentrate diets fed to growing lambs

CONCENTRATION OF SOME ELEMENTS IN BLOOD SERUM OF NONLACTATING GOATS IN A SUBTROPICAL REGION OF SOUTHWEST OF MÉXICO STATE

The objective of this study was to determine the mineral levels in blood serum of nonlactating adult goats in the south of the State of México during the dry and rainy seasons. Eighty four multiparous (>2 calving and non-lactating) does were sampled (LW 39 ± 8 kg). Blood samples were collected by jugular vein punction, followed by separation of blood serum by adding 10% trichloroacetic acid for later laboratory analysis. Data were analyzed as a completely randomized factorial experiment. There was as effect (P<0.05) of season on serum concentrations of P, and there was an interaction (P<0.01) of season*region for Ca, Na, Cu and Zn. Mg was unaffected by treatments. Results suggest possible deficiencies in the diets of P, Ca, Cu and Zn

In vitro gas production kinetics and degradability of a diet for growing lambs: effect of fibrolytic enzyme products at different dose levels

The objective of this study was to evaluate the effects of three fibrolytic enzyme products (cellulase (CEL), xylanase (XYL) and a 1:1 mixture of CEL and XYL (MIX)) at three dose levels (0, 1 and 3 lL/0.5 g DM) on the in vitro fermentation of a diet for growing lambs. Bottles were incubated for 96 h at 39 C. A mathematical model was used to estimate the parameters describing the gas production (GP) curve (b, c and L). Dry matter degradability (DMD) and fibre (NDFD and ADFD) degradability were determined at the end of the incubation period. Metabolisable energy (ME) and short chain fatty acids (SCFA) were calculated at 24 h of incubation. The asymptotic GP (parameter b) was affected (p<0.02) by enzyme product and dose level, with a significant linear response (p<0.05). Dose level affected ME and SCFA with a significant linear (p<0.05) and quadratic (p<0.01) response. The interaction between enzyme product and dose level was significant (p<0.05) for cumulative GP up to 72 and 96 h of incubation, pH, ADFD and DMD. The results suggest that application of exogenous cellulases has the potential to alter asymptotic GP and degradability of ADF and DM of a diet for growing lambs, but most of the results depend on the interaction between enzyme product and dose level. Future studies are required to determine the ideal combination between enzyme product and dose level for optimal degradation of ruminant feeds

The reinsertion of controlled internal drug release devices in goats does not increase the pregnancy rate after short oestrus synchronization protocol at the beginning of the breeding season

Trabajo de investigación cuya temática es la sincronización del estro en ovejas de pelo.This study aimed to evaluate the effect of reinserting controlled internal drug release (CIDR) devices after fixed-time artificial insemination (FTAI) on pregnancy rates in goats. Oestrus was synchronized with a short (5 days) CIDR protocol, and FTAI was conducted 54 hours after CIDR removal. According to the reinsertion of CIDR after FTAI, goats were assigned to three treatments: G0 control group (n = 29), no CIDR reinsertion; G7 group (n = 27), CIDR reinserted 7 days; G14 group (n = 29), CIDR reinserted 14 days. Blood samples were collected to determine progesterone levels. Oestrus appearance (92.9%), interval of CIDR removal to oestrus (IRE = 34.1 ± 1.1 hours), interval of oestrus onset to artificial insemination (IEAI = 20.2 ± 1.0 hours), mean duration of oestrus (38.4 ± 1.4 hours), and pregnancy rates (61.0%) were similar (P > .05) among groups. Progesterone concentrations were higher (P  .05) for all groups. In conclusion, reinsertion of CIDR for 7 or 14 days after a short oestrus synchronization protocol and FTAI did not increase the overall pregnancy rate of goats

Effects of exogenous enzymes and application method on nutrient intake, digestibility and growth performance of Pelibuey lambs

Pelibuey sheep is the main breed in the tropical and subtropical regions of Mexico, and high demand of sheep meat has favored the finishing of lambs in feedlots with diets containing high levels of grains. The objective of this study was to evaluate the effects of exogenous enzymes (EE) and application method on nutrient intake and digestibility and performance of growing Pelibuey lambs. Treatments were based on comparison of two different methods of adding an enzyme product (sprayed on the total mixed ration or applied orally to the lambs) versus control treatment (no added enzyme). Twenty-one Pelibuey lambs, weighing 15.7 kg (SD = 1.8 kg) initial body weight, were individually housed in shaded pens and assigned randomly to one of the three enzyme treatments. At the end of study (lasting for 45 days), three lambs from each treatment were randomly selected and adapted to a pants and harness designed for fecal collection to measure nutrient digestibilities. Total body gain and average daily gain were affected (P < 0.05) by supplemental EE. The application method of EE had significant (P < 0.05) effect on FCE and FCR, but no effects were observed on nutrient intake. Supplemental EE did improve (P < 0.05) the digestibilities of dry matter, organic matter, neutral and acid detergent fiber, but no differences were observed in crude protein digestibility. The application method of EE had significant (P < 0.05) effect on the digestibility of acid detergent fiber. Supplemental EE can improve body weight gain and nutrient digestibilities without affecting nutrient intake in Pelibuey lambs, but the results of feed conversion efficiency and acid detergent fiber digestibility depend on the application method used of the EE

Effects of exogenous enzymes and application method on nutrient intake, digestibility and growth performance of Pelibuey lambs

Pelibuey sheep is the main breed in the tropical and subtropical regions of Mexico, and high demand of sheep meat has favored the finishing of lambs in feedlots with diets containing high levels of grains. The objective of this study was to evaluate the effects of exogenous enzymes (EE) and application method on nutrient intake and digestibility and performance of growing Pelibuey lambs. Treatments were based on comparison of two different methods of adding an enzyme product (sprayed on the total mixed ration or applied orally to the lambs) versus control treatment (no added enzyme). Twenty-one Pelibuey lambs, weighing 15.7 kg (SD = 1.8 kg) initial body weight, were individually housed in shaded pens and assigned randomly to one of the three enzyme treatments. At the end of study (lasting for 45 days), three lambs from each treatment were randomly selected and adapted to a pants and harness designed for fecal collection to measure nutrient digestibilities. Total body gain and average daily gain were affected (P < 0.05) by supplemental EE. The application method of EE had significant (P < 0.05) effect on FCE and FCR, but no effects were observed on nutrient intake. Supplemental EE did improve (P < 0.05) the digestibilities of dry matter, organic matter, neutral and acid detergent fiber, but no differences were observed in crude protein digestibility. The application method of EE had significant (P < 0.05) effect on the digestibility of acid detergent fiber. Supplemental EE can improve body weight gain and nutrient digestibilities without affecting nutrient intake in Pelibuey lambs, but the results of feed conversion efficiency and acid detergent fiber digestibility depend on the application method used of the E

Información climática asociada a estaciones productivas para el ajuste de modelos estadísticos de sistemas bovinos bajo condiciones extensivas

Artículo de investigación publicado en revista internacional indizada.El objeto de este estudio fue desarrollar una metodología para clasificar épocas de nacimiento (EN) y evaluar su impacto en indicadores productivos al compararlas con un método tradicional de clasificación. Con información meteorológica, se generó un índice de aridez para clasificar las EN. Las EN propuesta y tradicional se compararon, incluyéndolas como grupo contemporáneo (GC= hato, sexo, año y EN) a modelos de evaluación genética de caracteres de peso vivo. Fueron estimados los componentes de varianza y valores genéticos (DEP) con sus exactitudes. La clasifica- ción propuesta explicó mayor variabilidad que la clasificación tradicional (≥9,8%). Los parámetros genéticos mostraron cambios importantes, siendo los más evidentes en peso al destete. Los modelos fueron diferentes de acuerdo a la prueba de razón de verosimilitudes (P<0,01). Se observó una mejora de estructura en los GC. Para los dos caracteres evaluados las correlaciones entre los valores genéticos de los animales fueron diferentes, lo que indica cambio en la jerarquización. Este método de clasificación de EN puede ayudar a mejorar el ajuste de modelos estadísticos en condiciones en las que exista la información climática necesaria para su implementación.Los autores agradecen al Consejo Nacional de Cien- cia y Tecnología por el financiamiento del proyecto CB168207 y al Instituto Politécnico Nacional a través del proyecto SIP20150746