Pasture Forage Research Articles

Cow’s milk contamination with 137Cs depending on quality and supply of pasturage

The results of studies on transferring of 137Cs to cow’s milk during the grazing season on two pastures in Narodychi district, Zhytomyr region, which differ in 137Cs ground deposition and intensity accumulation of radionuclide by herbage. It has been proposed a specific methodical approach for interpreting the radiological consequences of the pastures use by grazing cows. This approach is that the contamination of cow’s milk should be linked to the quality and supply of pasture forage. Research has found that in most cases reducing the quality and supply of pasture grass the activity of 137Cs in milk decreases, although this fact is less obvious to hospitals with severe particle size and high 137Cs ground deposition. This can be explained by 137Cs of the soil origin on contamination of cow’s milk.

Methods for estimating forage mass in pastures in a tropical climate

There are various methods to estimate the mass production of forage in pastures, but many are not accurate or unsuitable when used with certain species of fodder plants. Therefore, knowing the uses and limitations of the measurement techniques is important. This review aims to report the primary methods of estimating forage mass in pastures in tropical climates. Tropical grasses have the distinctive characteristic of temperate stem elongation, which influences growth and forage quality and may interfere in some techniques used to estimate the forage production. Measurement techniques of forage mass production that consider this variable are important for research and for the farmers in these regions. Among the various direct and indirect methods, the mass of forage grass species is the factor that determines the most appropriate measurement method. Currently, there is no single method that can be used in all situations; thus, knowing the type of biomass that will be evaluated and the best technique for that purpose is critical.

Acúmulo de forragem do capim marandu em função das fezes bovinas durante o ano

É possível que os efeitos das fezes sobre o acúmulo de forragem do pasto dependam do clima, específico em cada estação do ano. Dessa forma, objetivou-se avaliar a dinâmica do acúmulo de forragem da Brachiaria brizantha cv. marandu durante as estações do ano e em locais próximos ou distantes das fezes depositadas pelos bovinos na pastagem. O delineamento experimental foi em blocos ao acaso, com quatro repetições. Foram calculadas as seguintes variáveis-respostas: taxa de crescimento de folha (TCF), taxa de crescimento de colmo (TCC), taxa de crescimento total (TCT), taxa de senescência foliar (TSF), taxa de acúmulo de folha (TAF), taxa de acúmulo total (TAT) e utilização do pasto (UP). As fezes bovinas influenciaram a TCF, a TCT, a TAF e a TAT, com maiores valores (P<0,05) nas plantas próximas (64, 78, 54 e 68 kg/ha/dia de MS, respectivamente) em relação às distantes das fezes (51, 69, 41 e 58 kg/ha/dia de MS, respectivamente). Com exceção da TSF, que foi maior (P<0,05) no inverno (20 kg/ha/dia de MS), todas as demais características tiveram maiores valores no verão. A UP foi inferior (P<0,05) no inverno (11,9%), em comparação às demais estações do ano (88,7; 93,6 e 85,1% na primavera, verão e outono, respectivamente). Independentemente da estação do ano, a deposição de fezes bovinas no pasto de Brachiaria brizantha cv. marandu aumenta o crescimento da planta forrageira. O clima apresenta maior influência em relação à presença das fezes sobre o acúmulo de forragem do capim-marandu.

The Role of Trees and Pastures in Organic Agriculture

<p>Environmental concerns associated with annual row crop grain production – including soil erosion, soil carbon loss, intensive use of chemicals and petroleum, limited arable land, among others – could be addressed by converting conventional livestock production to an organic pasture based system. The inclusion of tree crops would further enhance the opportunity for feeding pasture- raised livestock by providing shelter and alternative feed sources. Biodiversity is an essential aspect of an organic farm plan. The idea of including tree crops and other perennials into the vision of an organic farm as a “living system” is very much compatible with the goals and philosophy of organic farming. Before modern no-till farming systems were developed, tree crops and pasture systems were found to provide similar benefits for controlling soil erosion and conserving soil carbon. For example, J. Russell Smith’s <em>Tree Crops: A Permanent Agriculture</em> (Smith, 1950) and pioneered tree crop agriculture as the alternative to annual row crops for protecting soils from erosion while producing livestock feed such as acorns, nuts, and fodder. A survey of Mid-Atlantic USA soils under pasture found 60% higher soil organic matter content than cultivated fields. Because United States Department of Agriculture’s National Organic Program (USDA-NOP) standards require dairy cattle consume pasture forage and limited grain (7 C.F.R. pt. 206), organic milk contains higher concentrations of omega-3 and fewer omega-6 fatty acids than conventional milk. Organic standards also state “the producer must not use lumber treated with arsenate or other prohibited materials for new [fence posts] installations or replacement purposes in contact with soil or livestock.” Black locust (<em>Robinia pseudoacacia</em>) is a fast growing renewable alternative to treated lumber with many attributes compatible with organic farming. This versatile tree fixes nitrogen (N), provides flowers for honey bees and other pollinators, and produces a highly durable dense wood ideal for fence posts useable for up to 50 year.</p>

FORAGES AND PASTURES SYMPOSIUM: Improving soil health and productivity on grasslands using managed grazing of livestock.

Beyond grazing, managed grasslands provide ecological services that may offer economic incentives for multifunctional use. Increasing biodiversity of plant communities may maximize net primary production by optimizing utilization of available light, water, and nutrient resources; enhance production stability in response to climatic stress; reduce invasion of exotic species; increase soil OM; reduce nutrient leaching or loading in surface runoff; and provide wildlife habitat. Strategically managed grazing may increase biodiversity of cool-season pastures by creating disturbance in plant communities through herbivory, treading, nutrient cycling, and plant seed dispersal. Soil OM will increase carbon and nutrient sequestration and water-holding capacity of soils and is greater in grazed pastures than nongrazed grasslands or land used for row crop or hay production. However, results of studies evaluating the effects of different grazing management systems on soil OM are limited and inconsistent. Although roots and organic residues of pasture forages create soil macropores that reduce soil compaction, grazing has increased soil bulk density or penetration resistance regardless of stocking rates or systems. But the effects of the duration of grazing and rest periods on soil compaction need further evaluation. Because vegetative cover dissipates the energy of falling raindrops and plant stems and tillers reduce the rate of surface water flow, managing grazing to maintain adequate vegetative cover will minimize the effects of treading on water infiltration in both upland and riparian locations. Through increased diversity of the plant community with alterations of habitat structure, grazing systems can be developed that enhance habitat for wildlife and insect pollinators. Although grazing management may enhance the ecological services provided by grasslands, environmental responses are controlled by variations in climate, soil, landscape position, and plant community resulting in considerable spatial and temporal variation in the responses. Furthermore, a single grazing management system may not maximize livestock productivity and each of the potential ecological services provided by grasslands. Therefore, production and ecological goals must be integrated to identify the optimal grazing management system.

Evaluating the use of plant hormones and biostimulators in forage pastures to enhance shoot dry biomass production by perennial ryegrass (Lolium perenne L.).

Fertilisation of established perennial ryegrass forage pastures with nitrogen (N)-based fertilisers is currently the most common practice used on farms to increase pasture forage biomass yield. However, over-fertilisation can lead to undesired environmental impacts, including nitrate leaching into waterways and increased gaseous emissions of ammonia and nitrous oxide to the atmosphere. Additionally, there is growing interest from pastoral farmers to adopt methods for increasing pasture dry matter yield which use 'natural', environmentally safe plant growth stimulators, together with N-based fertilisers. Such plant growth stimulators include plant hormones and plant growth promotive microorganisms such as bacteria and fungi ('biostimulators', which may produce plant growth-inducing hormones), as well as extracts of seaweed (marine algae). This review presents examples and discusses current uses of plant hormones and biostimulators, applied alone or together with N-based fertilisers, to enhance shoot dry matter yield of forage pasture species, with an emphasis on perennial ryegrass.

49 Influence of oat β-glucan on postprandial glycemic and insulinemic responses to a meal or oral sugar

s / Journal of Equine Veterinary Science 35 (2015) 400e417 405 49 Influence of oat b-glucan on postprandial glycemic and insulinemic responses to a meal or oral sugar J. Weir*, V. Robbins, J.M. Bobel, L.A. Skurupey, and L.K. Warren University of Florida, Gainesville, FL, USA Oats are a favored cereal grain in equine rations and are rich in b-glucan (BG). This soluble fiber has been linked to health benefits in humans, including lowered cholesterol and postprandial glucose and insulin. We hypothesized that oat BG would yield similar benefits in horses. Eight mature, clinically healthy Quarter Horses (mean ± SEM, 569 ± 2 kg) were used in a 4 X 4 Latin square design study to determine the effect of oat BG on glycemic and insulinemic responses. Horses were fed 4 diets differing in amount and source of BG for 22 d: cracked corn (low BG control), regular feed oats (moderate BG), a highBG oat variety (high BG), or corn top-dressed with a concentrated oat BG powder (high BG). Both high BG diets provided 170 mg BG/kg BW/d. All diets were isocaloric. Horses also had free access to pasture forage and were fed a vitamin/mineral supplement. In each of 4 periods, 2 horses were fed each diet. Blood samples were obtained on d 0 and 21 for determination of serum total cholesterol. On d 21, glycemic and insulinemic responses to the assigned treatment diet were evaluated after an 8-h fast. Meal size was standardized to provide 0.8 g NSC/kg BW (an amount equal to the habitual meal size for both oat diets, but a lowered meal size for diets containing corn). On d 22, glycemic and insulinemic responses to an oral dose of sugar (corn syrup, 0.15 mL/kg BW) were evaluated after an 8-h fast. At the completion of each 22-d period, horses underwent a 13-d dietary washout (corn control diet), followed by reallocation of treatments. Data were compared using mixed model ANOVA with repeated measures. Serum cholesterol was not affected by diet and averaged 75.2 ± 1.6 mg/dL. Time to consume the meal differed between diets (P < 0.0001), averaging 13.4 and 7.5 min for diets containing oats and corn, respectively. Insulin response to a meal was affected by diet (P < 0.0001), time (P < 0.0001) and diet time (P < 0.0001), where serum insulin was higher and remained elevated longer in response to meals containing oats (regular or high BG) compared with the 2 diets containing corn. In response to the oral sugar test, insulin was affected by time (P < 0.0001) and diet time (P 1⁄4 0.027), with a lower response in the 2 diets containing a high level of BG compared with the corn and regular oat diets. Diet did not affect glycemic responses to either the meal or the oral sugar test. Results of the meal test likely reflect differences in foregut starch availability between oats and corn. However, responses to the oral sugar test suggest that habituation to diets containing a high level of oat BG may reduce the magnitude of insulin response.

Growth promoting hormonal implant pellets coated with a polymeric, porous film promote weight gain by grazing beef heifers and steers for up to 200 days.

Two studies evaluated growth promoting effects of implant pellets (IP), each containing 3.5 mg estradiol benzoate (EB) and 25 mg trenbolone acetate (TBA), to which a polymeric, porous coating was applied. Trial 1 evaluated performance of heifers (n = 70/treatment, initial BW = 188 ± 2.2 kg) and steers (n = 70/treatment, initial BW = 194 ± 2.2 kg) implanted subcutaneously in the ear with 0 (SC), 2 (2IP), 4 (4IP), or 6 (6IP) pellets that delivered EB/TBA (mg/mg) doses of 0/0, 7/50, 14/100, and 21/150, respectively, over grazing periods of 202 d (heifers) or 203 d (steers). Animals received experimental treatments on d 0 and over the grazing period were managed as single groups by sex in a rotational grazing system. When pasture forage availability became limited, cattle were supplemented with preserved forage but not concentrate supplements. Weight gains by heifers treated with 2IP, 4IP, and 6IP were greater (P < 0.05) than SC heifers but not different from each other. Weight gains by steers treated with 2IP, 4IP, and 6IP were greater than SC steers (P < 0.05), and ADG by steers treated with 6IP was greater (P < 0.05) than steers given 2IP or 4IP. Trial 2 was a multisite grazing study performed with heifers and steers to compare ADG after treatment with one 6-pellet, coated implant delivering 21 mg EB and 150 mg TBA (6IP) to sham treated negative controls (SC) over a grazing period of at least 200 d. A completely random design was used at each site, with the goal to treat 70 cattle per site, treatment, and sex; data were pooled across sites. Heifers (n = 558, initial BW = 229 ± 16 kg) and steers (n = 555, initial BW = 235 ± 20 kg) grazed in rotational programs consistent with regional practices for an average of 202 d. When necessary, cattle were supplemented with preserved forage, but no concentrate supplements were fed. Over 202 d, ADG by heifers treated with 6IP was 11.3% greater (P = 0.0035) than SC heifers (0.64 ± 0.06 kg/d), and ADG by steers treated with 6IP was 17.2% greater (P = 0.0054) than SC steers (0.66 ± 0.08 kg/d). In neither study was there evidence that concurrent therapeutic treatments or abnormal health observations were influenced by experimental treatments. These studies demonstrated that a 6-pellet implant with a polymeric, porous coating that delivers 21 mg EB and 150 mg TBA improved ADG by grazing heifers and steers for at least 200 d compared to sham-implanted negative controls.

Modelling Pasture-based Automatic Milking System Herds: The Impact of Large Herd on Milk Yield and Economics.

The aim of this modelling study was to investigate the effect of large herd size (and land areas) on walking distances and milking interval (MI), and their impact on milk yield and economic penalties when 50% of the total diets were provided from home grown feed either as pasture or grazeable complementary forage rotation (CFR) in an automatic milking system (AMS). Twelve scenarios consisting of 3 AMS herds (400, 600, 800 cows), 2 levels of pasture utilisation (current AMS utilisation of 15.0 t dry matter [DM]/ha, termed as ‘moderate’; optimum pasture utilisation of 19.7 t DM/ha, termed as ‘high’) and 2 rates of incorporation of grazeable complementary forage system (CFS: 0, 30%; CFS = 65% farm is CFR and 35% of farm is pasture) were investigated. Walking distances, energy loss due to walking, MI, reduction in milk yield and income loss were calculated for each treatment based on information available in the literature. With moderate pasture utilisation and 0% CFR, increasing the herd size from 400 to 800 cows resulted in an increase in total walking distances between the parlour and the paddock from 3.5 to 6.3 km. Consequently, MI increased from 15.2 to 16.4 h with increased herd size from 400 to 800 cows. High pasture utilisation (allowing for an increased stocking density) reduced the total walking distances up to 1 km, thus reduced the MI by up to 0.5 h compared to the moderate pasture, 800 cow herd combination. The high pasture utilisation combined with 30% of the farm in CFR in the farm reduced the total walking distances by up to 1.7 km and MI by up to 0.8 h compared to the moderate pasture and 800 cow herd combination. For moderate pasture utilisation, increasing the herd size from 400 to 800 cows resulted in more dramatic milk yield penalty as yield increasing from c.f. 2.6 and 5.1 kg/cow/d respectively, which incurred a loss of up to $AU 1.9/cow/d. Milk yield losses of 0.61 kg and 0.25 kg for every km increase in total walking distance (voluntary return trip from parlour to paddock) and every one hour increase in MI, respectively. The high pasture utilisation combined with 30% of the farm in CFR in the farm increased milk yield by up to 1.5 kg/cow/d, thereby reducing loss by up to $0.5/cow/d (c.f. the moderate pasture and 800 cow herd scenario). Thus, it was concluded that the successful integration of grazeable CFS with pasture has the potential to improve financial performance compared to the pasture only, large herd, AMS.

Esterase polymorphism for genetic diversity analysis of some accessions of a native forage grass, Mesosetum chaseae Luces, from the Brazilian Pantanal

The aim of the present study was to estimate the genetic diversity within the samples of Mesosetum chaseae from the Embrapa Pantanal Germplasm Bank (BAG) and assess how they are genetically structured to guide proposals to: 1) identify native forages for further testing to measure their suitability for sowing in conjunction with or as an alternative to exotic forages, mainly Urochloa humidicola ; and 2) improve the species M. chaseae with samples that are maintained in the BAG. Isozyme α- and β-esterases were analyzed in 10 accessions collected from different locations in the Nhecolândia sub-region of the Pantanal, and maintained in the BAG. Accessions A11, which showed the highest effective number of alleles, and A32 with the highest average values of expected and observed heterozygosity, were identified as warranting further study as possible options for sowing as pasture forages, as well as for use in recovering poor and degraded areas in the Pantanal region. A high level of population differentiation was detected among the 10 accessions, indicating that they form genetically structured populations and that all accessions are important samples of M. chaseae , which should be maintained in the BAG. Crosses between sample plants with the highest genetic distances are recommended to implement improvement plans with a prospect of broadening the genetic base of the species. Keywords: Genetic polymorphism, genetic resources, grama-do-cerrado, isoesterases, Poaceae. DOI: 10.17138/TGFT(3)194-204

How the Intercropping between Corn and Palisade Grass Cultivars Affects Forage Production and Pastures Characteristics under Grazing

Crop-livestock integrated systems have been identified as an excellent option to use land efficiently. This study investigates how the intercropping between corn and three palisade grass cultivars affects the species productivity and the physiological and structural characteristics of swards grazed under 95% light interception under mob stocking. Evaluations were performed before corn harvest and during three grazing cycles. Similarity between the cultivars on the proportion of corn morphological components has shown that none of the studied forage plants had influence on the growth of corn. The crop-livestock integrated system with corn modified the proportion of palisade grass cultivars’ morphological components, promoting the development of Xaraes cultivar. In the pre-grazing in the grazing cycles, considering 95% of light interception the Xaraes cultivar showed higher height (0.47 m) compared with Marandu (0.37 m) and similar to Piata (0.42 m). Forage density was higher in the second grazing cycle only when the forage mass was also greater with greater contribution of both leaves and stems compared to the other cycles. Mass of leaves, stems and dead material was similar between the cultivars both pre- and post-grazing. The corn and forage intercropping did not affect the growth and development of palisade grass pastures and it is a viable alternative for the crop-livestock integrated system. Corn production is not affected by the palisade grass cultivars but production can be affected by environmental conditions mainly rainfall. The Marandu, Xaraes and Piata cultivars can be recommended for integration farming system in crop-livestock integrated system and are recommended for sward managed under 95% light interception and 15 cm high residue.

Herbage intake and animal performance of cattle grazing dwarf elaphant grass with two access times to a forage peanut area

Relatively short grazing periods in a pure legume pasture can be an alternative for increasing animal performance in medium-quality tropical pastures. Thus, the aim was to evaluate the herbage intake and animal performance of steers grazing dwarf elephant grass (Pennisetum purpureum Schum. cv. BRS Kurumi) with two access times [2 h (07:00 - 9:00) and 6 h (07:00 - 13:00)] to an area of forage peanut (Arachis pintoi cv. Amarillo). Twelve steers (219 ± 28.8 kg LW) were divided into four groups and assessed during three consecutive grazing cycles, from January to March 2013. The crude protein and neutral detergent fiber contents were 158 and 577 g/kg dry matter (DM) for dwarf elephant grass and 209 and 435 g/kg DM for forage peanut, respectively. The pre-grazing height and leaf mass of dwarf elephant grass and forage peanut were 94 cm and 2782 kg DM/ha and 15 cm and 1751 kg DM/ha, respectively. The herbage intake (mean = 2.7 ± 0.06% LW) and average daily weight gain (mean = 1.16 ± 0.31 kg/day) were similar for both treatments. However, animals with 2-h access to the legume paddock grazed for 71% of the time, whereas those with 6-h access grazed for 48% of the time. The performance of the steers that were allowed to graze forage peanut pasture for 2 h is similar to that of those that were allowed to graze the legume pasture for 6 h.

Characterization of butyrate transport across the luminal membranes of equine large intestine.

The diet of the horse, pasture forage (grass), is fermented by the equine colonic microbiota to short-chain fatty acids, notably acetate, propionate and butyrate. Short-chain fatty acids provide a major source of energy for the horse and contribute to many vital physiological processes. We aimed to determine both the mechanism of butyrate uptake across the luminal membrane of equine colon and the nature of the protein involved. To this end, we isolated equine colonic luminal membrane vesicles. The abundance and activity of cysteine-sensitive alkaline phosphatase and villin, intestinal luminal membrane markers, were significantly enriched in membrane vesicles compared with the original homogenates. In contrast, the abundance of GLUT2 protein and the activity of Na(+)-K(+)-ATPase, known markers of the intestinal basolateral membrane, were hardly detectable. We demonstrated, by immunohistochemistry, that monocarboxylate transporter1 (MCT1) protein is expressed on the luminal membrane of equine colonocytes. We showed that butyrate transport into luminal membrane vesicles is energized by a pH gradient (out<in) and is not Na(+) dependent. Moreover, butyrate uptake is time and concentration dependent, with a Michaelis-Menten constant of 5.6±0.45mm and maximal velocity of 614±55 pmol s(-1) (mg protein)(-1). Butyrate transport is significantly inhibited by p-chloromercuribenzoate, phloretin and α-cyano-4-hydroxycinnamic acid, all potent inhibitors of MCT1. Moreover, acetate and propionate, as well as the monocarboxylates pyruvate and lactate, also inhibit butyrate uptake. Data presented here support the conclusion that transport of butyrate across the equine colonic luminal membrane is predominantly accomplished by MCT1.

Judging and Evaluating Range and Pasture Forage Utilization (Proper Grazing Use) for Certain Portions of the Central Great Plains

• Many guidance documents and references have been prepared by federal and state agencies on proper grazing use. This article summarizes these documents for use by field personnel. • Proper grazing use or acceptable forage utilization can be judged by the use of key forage plants in designated key grazing areas.

Chicory (Cichorium intybus) responses to nitrogen and plant density in Birjand, Iran

Chicory is an important medicinal plant and also used as a leaf vegetable for pasture forage. In order to study the effect of nitrogen and pant density on this plant, an experiment was conducted in the 2009-2010 growing season at the Agricultural Training Center of Mohammadieh, Birjand, Iran. A split plot experiment based on a randomized complete block design with three replications was used. Nitrogen rates including of 0, 100 and 200 kg.ha-1 N as urea (N0, N100 and N200, respectively) were arranged in main plots and four planting density (25, 16.7, 12.5 and 10 plants.m -2 ) were employed in the subplots. The results indicated that nitrogen application had not any significant effect on dry root yield, but application of 200 kg.ha -1 N compared to control, increased dry leaf and total yields 39.85 and 31.89 percent, respectively. Although nitrogen application significantly decreased NUE but increasing plant density increased it. Increasing plant density enhanced root and leaf dry yield, but declined plant height, axillary root number and root length. Nitrogen application had not any significant effect on axillary root number and root diameter and length. The effect of nitrogen and plant density on root/shoot ratio was not significant. Totally the result showed that chicory's yield respond positively to increasing plant density (25 plant.m -2 ) and nitrogen rate (200 kg.ha -1 ) but increasing the yield was not proportionally to nitrogen fertilizer, consequently NUE declined in the highest nitrogen treatment.

Progress in the Brazilian cattle industry: an analysis of the Agricultural Censuses database

Brazil is the world’s largest exporter of beef and home to the world’s biggest commercial beef herd. So a study was conducted to understand how the Brazilian cattle industry has developed, by analysing the Agricultural Censuses carried out in 1985, 1995 and 2006. Databases (per region) were collected: bovine herd, total pasture area (natural and cultivated) and forage storage silos, and the stocking rate calculated (heads/ha). Brazilian regions are: North, North-east, South-east, South and Midwest. The average annual growth rate (%/year) was calculated. In 1985, Brazil had 128 million bovine heads, raised on 179.2 million hectares of pasture (0.71 head/ha). In 2006, the bovine herd went up to 176.1 million heads, raised on 160 million hectares of pasture (1.1 head/ha). The North region (Amazon forest) showed the highest growth in bovine herd (6.3%/year), and in total (1.2%/year) and cultivated (4.0%/year) pasture areas, increasing the stocking rate from 0.43 (1985) up to 1.21 head/ha (2006). The Midwest region accounted for the largest bovine herd in 2006 and showed the second highest growth in herd size (2.4%/year) and in cultivated (1.9%/year) pasture area, increasing the stocking rate from 0.61 (1985) up to 1.01 head/ha (2006). The South-east and South regions (the most developed regions) presented negative growth in herd size and total pasture, but with the highest stocking rate in 2006 (1.24 and 1.5 head/ha, respectively). The displacement of the cattle industry towards North concerns the government, due to the Amazon’s deforestation, but the intensification of the production system has relieved the pressure on the forest.

Increase and Decrease in Milk Production is affected by Pasture intake

Quality pasture reduces input costs and increases net returns, increases yield and quality of forage, decreases purchased feed, decreases equipment and fuel, decreases manure handling and bedding, better animal health and, reduces labor to feed or harvest the forage. Successes at maintaining good milk yield are generally due to an ability to optimize pasture yield and quality; supplement rations to meet energy requirements; and balance diets for undegradable protein in livestock rearing. Yields of high quality pasture forage can be similar to yields obtained on most farms that mechanically harvest forage for hay or silage. Quality pastures can achieve 4- 6 ton of dry matter per acre and can be grazed 6-9 times each season in the temperate and all year round in the tropical countries.An experiment was conducted to determine the Total Non-structural carbohydrates (TNC) of three napier grass (Pennisetumpurpurem) harvested at vegetative and reproductive phases. The cultivars tested were Taiwan (Gt), King (Gk), and Mott (Gm) and arranged in a 3 x 2 of treatments with four replicates following nested designed. The results showed that the highest sugar content (P<0.01) was found in Gt cultivar and the lowest was in Gm cultivar. The highest starch content (P<0.01) was found in in Gk cultivar and the lowest was in Gt cultivar. TNC content of Gt and Gk cultivars were not significantly different, but both were not significantly higher (P<0.01) compared with the Gm cultivar. It can be concluded from the study done that there were differences in TNC between cultivars, however, the TNC content in Gk cultivar was not different with Gt cultivar, while Gm cultivar have the lowest (P<0.01)TNC content. At reproductive phase all cultivars have higher (P<0.01) TNC and starch content than at vegetative phase. Napier grass (PennisetumPurpureumSchum) is a perennial grass, famous throughout the wet tropics because of its high production capability. Several cultivars have been developed and were introduced to Indonesia, Malaysia, Philippines and South East Asian Countries. Such as cultivars of Africa, Hawaii, Trinidad, Merkeri, King, Taiwan and Mott are closely related. There are differences between cultivars morphology, growth rate and response to farming practices that lead to differences in production and non-structural carbohydrate content.

Comparison of demographic characteristics, animal science subject knowledge, academic performance and critical thinking skills in students majoring in animal science and equine science

Comparison of demographic characteristics, animal science subject knowledge, academic performance and critical thinking skills in students majoring in animal science and equine science

Effect of Pasture or Maize Silage Feeding on the Nutritional Value of Beef

Effect of Pasture or Maize Silage Feeding on the Nutritional Value of BeefThe objective of this study was to evaluate the nutritional value of beef from different production systems. The study was conducted with Hereford bulls on organic and conventional farms. On the organic farm, fattening was mainly based on roughages, including pasture forage in the summer season, when the end of fattening occurred. On the conventional farm the bulls were fed maize silage and concentrate. On both farms, the animals were aged 7-9 months at the beginning of fattening. The bulls were fattened to a final body weight of 550-600 kg. Samples oflongissimus thoracismuscle were collected from half-carcasses of slaughtered bulls originating from each farm to analyse fat content, fatty acid profile, and content of selected minerals and vitamin E. Muscle samples were additionally analysed for the concentration of thiobarbituric acid-reactive substances 3 and 7 days after slaughter. Analyses showed a lower fat content inlongissimus thoracismuscle of bulls from the pasture feeding system. The fatty acid profile was also characterized by a lower content of C 14:0, and a higher content of polyunsaturated fatty acids (PUFA), including C18:3n-3, conjugated linoleic acid, C 20:5n-3, and C 22:5n-3, as well as by a lower ratio ofn-6/n-3 PUFA. The total content of monounsaturated fatty acids was significantly higher in animals fed maize silage and feed concentrate. In turn, the muscle of pasture fed animals had higher levels of Na, Zn and Fe as well as of vitamin E.

Growth performance, ruminal fermentation profiles, and carcass characteristics of beef steers grazing tall fescue without or with nitrogen fertilization

A 2-yr study was conducted to evaluate the effects of finishing beef cattle grazed on tall fescue (TF) pastures without or with N fertilization on growth performance, ruminal fermentation, and carcass characteristics. In each grazing season, 18 Angus crossbred steers were arranged in a completely randomized design with repeated measures on the following 2 treatments: TF without N fertilizer (TF–NF) and TF with N fertilizer (TF+NF). Three replicated pastures with 3 steers per replicate were assigned to each treatment. A total of 168 kg/ha N fertilizer was applied in 3 split applications at 56 kg/ha each to the TF+NF in each grazing season. Steers rotationally grazed on 0.47-ha pasture for 7 d with a 28-d rotation interval for a total of 16 wk. Body weight data and pasture forage samples were collected every 4 wk, whereas ruminal fluid was collected at wk 4, 10, and 16. After the completion of 16-wk grazing, ultrasound measurement was performed to assess carcass characteristics. In response to N fertilization, greater CP concentration was detected on TF+NF compared with TF–NF in 2011 (11.9 vs. 10.6% DM, respectively; P < 0.01). Overall ADG was greater in steers that grazed TF+NF pastures (P < 0.05) in the 2-yr grazing seasons, and tended to increase (P = 0.07) overall DMI and G:F in 2010. Regardless of N fertilization, ADG peaked between wk 4 and 8 (1.05 kg/d; P < 0.01), and then declined until wk 16. A gradual decline of G:F was noticed with progression in grazing seasons (P < 0.05). Greater total VFA concentrations were detected in ruminal fluid of steers that grazed TF+NF (P < 0.01), but a minor effect was shown on individual VFA (acetate, propionate, and butyrate) concentrations and acetate-to-propionate ratio. Ruminal ammonia-N (NH3-N) concentration increased (P < 0.01) with N fertilization, whereas NH3-N:total VFA increased (P < 0.01) with the progression of grazing seasons. Backfat thickness, ribeye area, and intramuscular fat concentration did not differ between treatments. Overall results of this study indicate that N fertilization on TF affected ruminal fermentation which positively influenced growth performances, but did not affect carcass characteristics of grazing beef steers. In addition, readily fermentable carbohydrate supplementation is needed to improve utilization of increased dietary CP due to N fertilization and consequently enhance growth performances of grazing steers.