ESTADÍSTICA DESCRIPTIVA

SÓLO VISIÓN PROYECTABLE

PROBABILIDAD Y DISTRIBUCIONES

SÓLO VISIÓN PROYECTABLE

EMPLEO DE CRUZAMIENTOS EN LA INDUSTRIA OVINA

SÓLO VISIÓN PROYECTABLE

Concentrate supplementation on milk yield, methane and CO2 production in crossbred dairy cows grazing in tropical climate regions

The objective of this study was to evaluate the level of concentrate supplementation on the production and chemical composition of milk from 12 crossbred F1 dual-purpose cows ( Bos taurus – Bos indicus) and estimate the emission of CH4, N2O, and CO2 gases. The study included 12 crossbred F1 dual-purpose cows over 60 days of lactation. The cows grazed on 28% tropical native grassland and 72% Brachiaria spp. and Cynodon neumfluensis, supplemented with 0, 150, 300, and 450g of concentrate per kg daily milk production, during three experimental periods of 15 days each in a crossover design. Pasture and concentrate samples were collected and were analyzed for dry matter, crude protein, neutral detergent fiber, and acid detergent fiber. Milk production (kg d-1) was recorded daily, nitrous oxide (N2O), and emissions from excreta and daily CH4 production were calculated. Results were analyzed with the SAS MIXED procedure. Concentrate supplementation in tropical crossbred dairy cows did not improve milk yield but increased CH4 and N2O production (P < 0.0001) per cow as the concentrate increased in the diet; the Ym factor from the tropical region yielded less CH4 than the IPCC Ym model (P < 0.0001). In conclusion, the calculation of CH4 using specific emission factors for the tropical climate region is better than the IPCC default emission factors in order not to overestimate the CH4 emissions

Clinical use of the parasympathetic tone activity index as a measurement of postoperative analgaesia in dogs undergoing ovariohysterectomy

El articulo ya esta aceptado y sale publicado en el volumen de marzo que es el primero de este año 2021. Adjunto link http://jvetres.piwet.pulawy.pl/index.php/archive-pdf-a-abstractsAbstract Introduction: While the current tools to assess canine postoperative pain using physiological and behavioural parameters are reliable, an objective method such as the parasympathetic tone activity (PTA) index could improve postoperative care. The aim of the study was to determine the utility of the PTA index in assessing postoperative analgaesia. Material and Methods: Thirty healthy bitches of different breeds were randomly allocated into three groups for analgaesic treatment: the paracetamol group (GPARAC, n = 10) received 15 mg/kg b.w., the carprofen group (GCARP, n = 10) 4 mg/kg b.w., and the meloxicam group (GMELOX, n = 10) 0.2 mg/kg b.w. for 48 h after surgery. GPARAC was medicated orally every 8 h, while GCARP and GMELOX were medicated intravenously every 24 h. The PTA index was used to measure the analgaesia–nociception balance 1 h before surgery (baseline), and at 1, 2, 4, 6, 8, 12, 16, 20, 24, 36, and 48 h after, at which times evaluation on the University of Melbourne Pain Scale (UMPS) was made. Results: The baseline PTA index was 65 ± 8 for GPARAC, 65 ± 7 for GCARP, and 62 ± 5 for GMELOX. Postoperatively, it was 65 ± 9 for GPARAC, 63 ± 8 for GCARP, and 65 ± 8 for GMELOX. No statistically significant difference existed between baseline values or between values directly after treatments (P = 0.99 and P = 0.97, respectively). The PTA index showed a sensitivity of 40%, specificity of 98.46% and a negative predictive value of 99.07%. Conclusion: Our findings suggest that the PTA index measures comfort and postoperative analgaesia objectively, since it showed a clinical relationship with the UMPS

Ensilado de maíz, una revisión sistemática de la calidad y el rendimiento en diferentes regiones del mundo

Corn sialge (Zea mays L.) is the most widely used in the world in dairy cattle diets because of its higher biomass yields, palatability, homogeneous quality at harvest, and ease of silage due to its higher soluble sugar content. Studies were systematically searched to know the silage corn quality and yield from different countries concerning dry matter yield (t/ha), population density (plant density/ha), quantity of Dry Matter (DM), Crude Protein (CP), Neutral Detergent Fiber (NDF), Non-Fibrous Carbohydrates (NFC), Organic Matter (OM), DM Digestibility (DMD), Neutral Detergent Fiber Digestibility (NDFD), and milk production  (kg) per hectare (kg milk/ha) using MILK2006®. Six clusters (CL, PROC CLUSTER) of corn silage were analyzed: CL1: “Starch,” which included DMD, DNDF, TDN1 x DM, Mega calories per kg of DM, and kg of milk/t DM; CL2: “ether extract” which included TDN1 x DM, Mcal/kg DM, and kg of milk/t DM; CL3: “DM,” composed only of DNDF; CL4: “Plant Density,” including Yield of DM/ha and Milk Production/ha; CL5: “NDF,” and CL6: “CP.” In conclusion, CL1 is characterized by a higher DMD, NDFD, CNF, and starch, which allow higher TDN1 x DM and an energy concentration (Mcal/kg DM) with higher milk production (kg milk/ha). CL2 with a higher ether extract (EE) allows higher TDN1 x DM and an energy concentration (Mcal/kg DM) having a higher milk production (kg milk/ha). The DM concentration increases in the whole plant because of maturity, affecting the starch content and NDFD; the DM content (&gt; 35 g/100 g DM) mainly causes a decrease in the NDFD, while in a very early stage of DM harvest (&lt; 25 g/100 g DM) a low ratio of starch:NDFD is present.El ensilado de maíz (Zea mays L.) es el más utilizado en el mundo en dietas de ganado lechero por sus mayores rendimientos de biomasa, palatabilidad, calidad homogénea a la cosecha y facilidad de ensilar por su mayor contenido de azúcar soluble. Se realizó una búsqueda sistemática de estudios para conocer la calidad y el rendimiento de ensilados de maíz en diferentes países con relación al rendimiento de materia seca (t/ha), densidad de población (densidad de plantas/ha), Materia Seca (MS), Proteína Cruda (PC), Fibra Detergente Neutra (FDN), Carbohidratos No Fibrosos (CNF), Materia Orgánica (MO), Digestibilidad de la MS (DMS), Digestibilidad de Fibra Detergente Neutra (DFDN) y producción de leche por hectárea (kg de leche/ha), mediante el programa MILK2006®. Se analizaron 6 clúster (CL, PROC CLUSTER) de ensilado de maíz: CL1: “Almidón”, que incluyó DMS, DFDN, TDN x MS, Mega calorías por kg de MS y kg de leche/tonelada/MS; CL2: “extracto de éter” que incluyó TDN1 x MS, Mcal/kg MS y kg de leche/tonelada MS; CL3: “MS”, conformado solo por DFDN; CL4: “Densidad de plantas” incluyendo el Rendimiento de MS/ha y Producción de leche/ha, CL5: “FDN” y CL6: “PC”. El CL1 se caracterizó por una mayor DMS, DFND, CNF y almidón que permiten una mayor TDN1 x MS y una concentración de energía (Mcal/kg MS) que muestra una mayor producción de leche (kg de leche/tonelada MS/ha). Las características de CL2 con mayor extracto de éter (EE), permiten un mayor TDN1 x MS y concentración de energía (Mcal/kg MS) con mayor producción de leche (kg de leche/tonelada MS/ha) en comparación con otros clústeres. La concentración de MS aumenta en toda la planta por efecto de la madurez, lo que afecta el contenido de almidón y DFDN; el contenido de MS (&gt; 35 g/100 g MS) provoca principalmente una disminución de la DFDN, mientras que en una etapa muy temprana de cosecha de MS (&lt; 25 g/100 g MS) se presenta una baja relación almidón-DFDN

Cardiovascular effects of constant rate infusions of lidocaine, lidocaine and dexmedetomidine, and dexmedetomidine in dogs anesthetized at equipotent doses of sevoflurane

This study evaluated the cardiovascular effects of a constant rate infusion (CRI) of lidocaine, lidocaine and dexmedetomidine, and dexmedetomidine in dogs anesthetized with sevoflurane at equipotent doses. Treatments consisted of T1-Lidocaine [loading dose 2 mg/kg body weight (BW), IV, and CRI of 100 g/kg BW per min] at 1.4% end-tidal of sevoflurane (FESEV); T2-Dexmedetomidine (loading dose 2 g/kg BW, IV, and CRI of 2 g/kg BW per hour) and FESEV 1.1%; and T3-Lidocaine-Dexmedetomidine using the same doses of T1 and T2 and FESEV 0.8%. Constant rate infusion of lidocaine did not induce any cardiovascular changes; lidocaine and dexmedetomidine resulted in cardiovascular effects similar to dexmedetomidine alone. These effects were characterized by a significant (P 0.001) decrease in heart rate, cardiac output, cardiac index, oxygen delivery, and pulmonary vascular resistance index, and a significant (P 0.001) increase in mean and diastolic arterial pressure, systemic vascular resistance index, pulmonary arterial occlusion pressure and oxygen extraction ratio, compared with baseline values. In conclusion, a CRI of lidocaine combined with dexmedetomidine produces significant cardiovascular changes similar to those observed with dexmedetomidine alone

Effect of different growth stages of rapeseed (brassica rapa L.) on nutrient intake and digestibility, nitrogen balance, and rumen fermentation kinetics in sheep diets

The objective of the present study was to determine the dietary effect of different growth stages of rapeseed (Brassica rapa L.) on nutrient intake and digestibility, nitrogen balance, and rumen fermentation kinetics in sheep.The objective of the present study was to determine the dietary effect of different growth stages of rapeseed (Brassica rapa L.) on nutrient intake and digestibility, nitrogen balance, and rumen fermentation kinetics in sheep. Four dietary treatments were utilised. A basal control diet based on alfalfa hay, oat hay, soybean meal and corn grain. Then alfalfa hay was replaced with 300 g/kg DM of rapeseed forage harvested at three different growth stages: Vegetative, Flowering and Pod. In vitro gas production was determined using three rumen cannulated Suffolk sheep in a completely randomised design, and nutrients intake and digestibility of each diet were determined using four Suffolk sheep in a 4 4 Latin square design with 21 d periods consisting of 14 d for diet adaptation and 7 d for sample collection. Feed intake and excretion of faeces and urine were recorded. Dry matter intake was higher for control and Pod compared to Vegetative and Flowering. The digestibility of dry matter, organic matter, neutral detergent fibre and acid detergent fibre were similar among treatments. Nitrogen intake was higher for control and Pod and lower for Vegetative and Flowering. In vitro gas production was similar among treatments (P > .05). In vitro gas yield at 24 h was higher (P < .05) for control than the rest of the treatments. Overall, inclusion of 300 g/kg DM of rapeseed forage harvested at pod stage as a substitute for alfalfa hay is an alternative source of protein without affecting nutrient intake and digestibility.Amelia Zetina Sanchez thanked the National Council for Science and Technology (Conacyt, Mexico) for the scholarship for her studies at the Universidad Nacional Autonoma de Mexico. Lizbeth Esmeralda Robles Jimenez was awarded a Conacyt-Mexico scholarship during her PhD program at the Agricultural Sciences and Natural Resources at the Universidad Autonoma del Estado de México. During the study, Dr. Einar Vargas-Bello-Pérez was a visiting scholar also supported by project number 4974/2020CIB from Universidad Autonoma del Estado de México

GUÍA PEDAGÓGICA DE LA UNIDAD DE APRENDIZAJE DE MEJORAMIENTO GENÉTICO

GUÍA PEDAGÓGIC