Higher Metabolizable Energy Research Articles

Cranberries (Vacciniummacrocarpon aiton) in dog nutrition: influence on diet digestibility and palatability and in the course of urinary tract infections

ABSTRACT The objective was to evaluate the effects of cranberry on blood and urinary parameters of dogs (experiment I), digestibility of nutrients (experiment II), palatability of diet (experiment III) and the influence of cranberry on E. coli UPEC-MRHA fimbriae in vitro (experiment IV). For experiment I and II, ten dogs were fed with diets containing 0% or 0.4% cranberry for 30 days. Experiment III compared the diets containing 0% and 0.4% cranberry using 16 adult dogs. There were no statistical differences (P>0.05) in the blood parameters evaluated. Dogs consuming cranberry presented lighter color and appearance of urine, compared to the control group (P<0.05). The diet containing cranberry showed higher digestibility of dry matter, organic matter, ether extract, higher metabolizable energy (P<0.05) and reduced fecal sialic acid concentration (P<0.05) compared to the control diet. There was no influence of cranberry on the formation of fimbriae of E. coli UPEC-MRHA. There was a lower intake ratio of the diet containing cranberry (P<0.05). The inclusion of 0.4% cranberry increases the digestibility of nutrients and influences the color and appearance of urine of dogs. However, it reduces diet palatability and does not alter the adhesion of E. coli UPEC-MRHA in vitro.

The Feral Pig in a Low Impacted Ecosystem: Analysis of Diet Composition and Its Utility

The feral pig is an exotic species in the Sierra La Laguna Biosphere Reserve, Baja California Sur, Mexico, and is considered harmful to the woodlands and tropical deciduous forest because of its foraging habits. To determine the taxonomic, nutrient, and energy content of the feral pig diet in this area, stomach contents of forty feral pigs were analyzed during the dry and rainy seasons in the woodlands and the tropical deciduous forest. Results indicate that feral pigs are frugivore-herbivore and stenophagous, feeding on a high percentage of fruits and seeds (77–87%) that provide high metabolizable energy (8293–11,585 kJ kg−1 dry matter) and moderate crude protein (94.1–151.6 g kg−1 dry matter) year round in the woodland and during the dry season in the tropical deciduous forest, or high percentage of leaves, stems, and tubers (44%) that provide low metabolizable energy (4740 kJ kg−1 dry matter) and moderate crude protein (107.5 g kg−1 dry matter) in the rainy season in the tropical deciduous forest. Therefore, diets based on fruits and seeds favor a lower quantity of food to meet the energy for maintenance of feral pigs than those based on other plant tissues: pine nuts < acorns ≈ wild figs < leaves, stems, and tubers. The observed diet based on acorns, along with estimates of acorn production results in a carrying capacity estimate of 0.031 adult feral pig ha−1 yr−1 during years of low acorn production. Thus, feral pigs in the area use fruits and seeds in both woodlands and tropical deciduous forest because of their quality as food resources. The availability of the food resources preferred by pigs (pine nuts, acorns, fan-palm fruits, and wild figs) during the year can be used to inform potentially sustainable feral pig carrying capacities and establish hunting programs.

NUTRIENT CONTENT OF SOYBEAN MEAL FROM DIFFERENT ORIGINS BASED ON NEAR INFRARED REFLECTANCE SPECTROSCOPY

Near infrared reflectance spectroscopy (NIRS) has become common techniques to estimate chemical composition of feed ingredient for poultry. Two experiments were performed: first was to compare the capability of NIRS system from three laboratories (E, A and T) to measure nutrient composition of soybean meal (SBM); and the second was to evaluate nutrient composition and quality of 59 samples of SBM from Argentine, Brazil and US using NIRS from T-laboratory. Thirty samples of SBM was used in the first study and the result showed that all NIRS systems were able to estimate proximate, amino acids, metabolizable energy (ME) and carbohydrate components. The second experiment indicated that there were some differences in proximate composition (especially protein), total amino acids and digestible amino acids among SBM from different origins. Brazilian SBM had 2% higher protein and amino acid compared to US or Argentine SBM (P&amp;lt;0.05). However, US SBM had slightly higher ME (20 and 40 kcal kg&lt;sup&gt;-1&lt;/sup&gt;) compared to Brazilian and Argentine SBM, respectively. ME is positively correlated with protein (0.50) and fat content (0.58) but negatively correlated with fiber (-0.74) and NSP (-0.61). Stepwise regression analysis demonstrated that ME can be estimated using equation ME (kcal kg&lt;sup&gt;-1&lt;/sup&gt;) = 75.7 – 21.0 x Fiber + 87.4 x Fat + 32.9 x Protein + 17.6 x NFE with reasonable accuracy (R&lt;sup&gt;2&lt;/sup&gt; = 0.995). In conclusion NIRS can be used to estimate nutrient content of SBM. Brazilian SBM has higher protein and amino acids, but US SBM has slightly higher ME content.

Potential of herbaceous vegetation as animal feed in semi‐arid Mediterranean saline environments: The case for Tunisia

AbstractWith the depletion in arable land due to climate change, the use of naturally salt‐tolerant species to provide forage resources in arid and saline environments has become an emerging strategy. This study surveyed and determined the nutritive value of selected Tunisian vegetative species for use in Mediterranean saline environments. Eighteen wild species were analyzed for their nutrient contents and antinutritional factors. Chenopodiaceae accumulated more NaCl than Poaceae. Arthrocnemum indicum had the highest crude protein (CP) content, and Stipa roterta had the lowest. Poaceae had the highest fiber constituents (neutral and acid) and the lowest oxalate contents. Daily net gas production (GP) in the Chenopodiaceae and Poaceae ranged from 9.5 to 14.5 and from 13.8 to 37.9 ml per 0.2 mg dry matter (DM), respectively. Total phenol content and organic matter digestibility were species dependent. The metabolizable energy (ME) in the tested species ranged from 4.6 to 9.4 MJ kg−1 DM, with Catapodium rigidum and Arthrocnemum indicum having the lowest and highest ME values, respectively. In crux, Chenopodiaceae had the highest NaCl, CP, ME, and oxalate contents but had the lowest fiber and net GP. Sodium chloride content was positively correlated with CP and oxalate and negatively correlated with net GP. In arid and saline environments, where high salinity prevails and fodder resources are scarce, salt‐tolerant plants such as Suaeda fruticosa, Arthrocnemum indicum, and Halocnemum strobilaceum could be included in ruminant feeding calendars.

Nutritional Value of White Button Mushroom (Agaricus bisporus) Which is Most Widely Consumed in Kurdistan Region-Iraq

This study was conducted in 2018, at Technical College of Applied Sciences, Sulaimani Polytechnic University, Kurdistan Region-Iraq. The aim of the study was to determinate nutritional compositions and some elemental contents in marketable white button mushroom (Agaricus bisporus) that is collected in local markets of Kurdistan Region-Iraq. Five different samples (A: Penjwen product fresh, B: Sulaimani product fresh, C: American caned, D: Valencia Netherlandcaned and E: Erbil product fresh) were collected to be observed. The elements were analyzed by Atomic Absorption Spectrometry methods, and their chemical compassions were determined, too. The collected data were analyzed by One Way ANOVA. The highest fat, protein, fiber and dry matter were obtained from treatment B (3.93%, 43.693%, 15.8% and 10.611%) respectively, and the highest carbohydrate and moisture were found from treatment D (49.267% and 95.053%). The maximum percentage of ash was taken from E (14.11%). Moreover, the highest metabolizable energy was taken from treatment D (296.105 kcal %) and the lowest was taken from parameter E (223.097 kcal %). The highest mineral contents (Zn:15, Mn:1.1, Cu:3.5, Ni:1, Ca:6.7 and Mg:90 ppm) from B, (Fe:15 ppm) from C, (Si:350ppm) from A, and (Na:1080 ppm) from D were taken. However, the lowest elemental contents (Fe:6, Mn:0.48, Ni:0.6, Na:180 and Ca:3.5 ppm) from E, (Zn:5, Cu:0.9 and Mg:35 ppm) from D and B (Si:120 ppm) were taken. Therefore, we recommend carrying out more studies on micronutrients for different marketable crops and consuming fresh mushroom instead of caned mushrooms.

Forage Performance and Detection of Marker Trait Associations with Potential for Napier Grass (Cenchrus purpureus) Improvement

The evaluation of forage crops for adaptability and performance across production systems and environments is one of the main strategies used to improve forage production. To enhance the genetic resource base and identify traits responsible for increased feed potential of Napier grass, forty-five genotypes from Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA), Brazil, were evaluated for forage biomass yield and feed nutritional quality in a replicated trial under wet and dry season conditions in Ethiopia. The results revealed significant variation in forage yield and feed nutritional qualities among the genotypes and between the wet and dry seasons. Feed fiber components were lower in the dry season, while crude protein, in vitro organic matter digestibility, and metabolizable energy were higher. Based on the cumulative biomass and metabolizable energy yield, top performing genotypes were identified that are candidates for future forage improvement studies. Furthermore, the marker-trait association study identified diagnostic single nucleotide polymorphisms (SNP) and SilicoDArT markers and potential candidate genes that could differentiate high biomass yielding and high metabolizable energy genotypes in the collection.

Dallıdarı (Panicum virgatum)’da Farklı Biçim Sıklıklarının Yem Verimi ve Bazı Silaj Kalite Özelliklerine Etkisi

Bu çalışma, farklı biçim sıklıklarının dallıdarı (Panicum virgatum) bitkisinde ot verimi ve bazı silaj yem kalite özelliklerine etkisini saptamak amacıyla yürütülmüştür. Çalışma 2017 yılında, Ege Üniversitesi Ziraat Fakültesi Tarla Bitkileri Bölümü’nün Bornova deneme tarlalarında gerçekleştirilmiştir. Üç tekerrürlü olarak düzenlenen tarla denemesinde, 5 yaşındaki ‘Cloud Nine’ isimli dallıdarı genotipi kullanılmıştır. Denemede, bitkiler üzerinde altı farklı biçim sıklığı (30, 60, 90, 120, 150, 180 günde bir) test edilmiştir. Çalışmada, yaş ot verimi, bitki boyu, kuru madde oranı, silaj pH’sı, ham protein oranı, metabolik enerji (ME) ve nispi yem değeri gibi özellikler ölçülmüştür. Sonuçlar, biçim sıklıklarının dallı darının yaş ot verimi ve bazı silaj yem kalite özellikleri üzerinde önemli etkilerinin olduğunu, biçim sıklığı azaldıkça ME ve nispi yem değerlerinin (NYD) azaldığını göstermiştir. Akdeniz ikliminin sulu koşullarında yetiştirilen dallı darı bitkisinde 60 günde bir yapılan biçimlerin yaş ot verimi göz önüne alındığında en başarılı biçim sıklığı olduğu belirlenmiştir. ME ve NYD yönünden ise en yüksek değerler 30 günde bir biçim yapılan uygulamalardan elde edilmiştir.

Study of on-farm pre and post-natal feeding practices of Red Chittagong Cattle

The study was conducted with the objective to investigate prenatal and postnatal performances of Red Chittagong Cattle (RCC) cows in subsistence feeding and nutrition compared to those in improved feeding system. Twenty RCC cows with average initial live weight of 204.6 (±29) kg at their 2nd or 3rd parity and at about seven months of pregnancy were divided into two equal groups and assigned to two dietary treatments: one group was fed as per farmers’ choice, while another was fed 25% higher metabolizable energy (ME) and crude protein (CP) than requirements through concentrates, according to ARC (2009). Cows in farmers’ diet during last 50 days of pregnancy fed lower ME and CP (42.4 MJ and 445 g, respectively) than their daily requirements (43.5 MJ and 519 g, respectively), resulted in lower birth weight of calves compared to improved feeding (13.36 and 15.12 kg, respectively) where daily ME and CP intake was 57.77 MJ and 603 g. In first 60 days of lactation, cows under farmers’ diet fed required amount of ME and CP (44.83 MJ and 471g, respectively) compared to requirement (42 MJ and 388g, respectively). However, cows in improved diet fed 1.28 and 1.42 times higher ME and CP (52.92 MJ and 563 g) than requirements, and produced higher milk (1.97 and 2.50 L/d; P&lt;0.05) and daily gain (122 and 274 g/d; P&lt;0.01), compared to that of farmers’ diet cows. Therefore, it was concluded that diet of RCC cows in late pregnancy may be supplemented with CP in order to produce higher birth weight of calves. In case of lactating cows, a cost effective supplementation of concentrate mixture for increasing milk production and daily gain may be investigated by doing further research.&#x0D; Bangladesh J. of Livestock Res. 21-25: 159-167, 2018

In vitro gas production and rumen fermentation profile of fresh and ensiled genetically modified high–metabolizable energy ryegrass

We previously generated a high-metabolizable energy (HME) perennial ryegrass (Lolium perenne) by genetically modifying the plant to increase the leaf lipid content. Although substantial progress has been made toward characterizing physiological changes of HME ryegrass, very limited information exists for feeding value and its suitability for adoption into the pastoral system. In this study, independent HME ryegrass lines with a range of elevated leaf lipid concentrations were analyzed for changes in fatty acids and possible associated changes in the broader nutritional profile, including the gross energy, which was found to increase by 6.8%. Because ryegrass is often ensiled and fermentation in the rumen leads to biohydrogenation of fatty acids as well as enteric methane production, we sought to investigate these effects on HME ryegrass. This was achieved by performing mini-scale silos and using an automated gas measurement system to incubate the material in rumen fluid in vitro for 24 h. Our study included treatments comprising 3 independent HME ryegrass genotypes and wild-type control materials prepared fresh and as silage, employing in total 5 incubation studies, using rumen fluids collected from 4 nonlactating Jersey × Holstein cows. At intervals during the incubation, the production of gases, volatile fatty acids, and the degree of biohydrogenation were measured. Statistical data analysis indicated that differences in the nutritional compositions of the ensiled materials largely reflected those of their fresh counterparts. Incubation of both fresh and ensiled HME ryegrass in rumen fluid resulted in: (1) a greater percentage of valuable unsaturated fatty acids compared with the control; (2) a significant reduction of butyrate; and (3) a 10 to 15% decrease in the methane proportion of the total gas production. We conclude that ensiling could be a convenient option for preserving HME as a locally produced high-value supplementary feed; however, large-scale application needs to be investigated. In this paper we discuss the potential use of HME ryegrass to enhancing forage feeding value and the potential environmental benefits to the pastoral agriculture industry.

Chemical characterization and in vitro methane production of selected agroforestry plants as dry season feeding of ruminants livestock

The vagaries in climatic changes disrupt the prevailing weather conditions leading to temperature extremes and protracted rainfall pattern which subsequently affect the quality of forages. Ruminant animals had been implicated as a major source of enteric methane production to the greenhouse effect. Grazing on this low-quality forages extends the time of fattening thereby increasing the amount of methane produced. In this case, effort has been shifted to the feeding of agroforestry plants (browse and tree species) which are available all year round with high nutritive profile. Leaves of selected agroforestry plant species Thevetia peruviana (Pers) K. Schum, Piliostigma thonningii (Schumach.) Milne-Redhead, Spondia mombin L. and Newbouldia laevis (P. Beauv.) Seem were harvested, dried, milled and analysed for their chemical constituents, mineral composition, in vitro and methane gas production. Data collected were analysed using one-way analysis of variance. Significant (p < 0.05) differences were observed in the nutritive value of the selected plants except for dry matter and ether extract contents. NDF values ranged from 606.7 g/kg in T. peruviana to 666.7 g/kg in P. thonngii. P. thonngii recorded the highest value (533.3 g/kg) for acid detergent fibre with the lowest value (500.0 g/kg) observed in N. laevis. There were significantly (p < 0.05) differences among the recorded mineral components of selected plants except for Mn. N. laevis had the highest volume of gas, while P. thonngii had the least. However, N. laevis had the least (p < 0.05) insoluble fibre fraction (b), methane gas production with considerably highest metabolizable energy. With the appreciable level of nutrients, especially in terms of crude protein content and reduced methane production, research into various agroforestry plants will be of high interest to be adopted in ruminant diets.

Dry Season Feeding Technologies: Assessing the Nutritional and Economic Benefits of Feeding Hay and Silage to Dairy Cattle in South-Western Uganda

South-western Uganda annually experiences prolonged drought that results in dramatic drop in milk production of dairy cattle. This study was conducted to assess the nutritional value and economic benefits of feeding silage and hay to dairy cattle in the sub-region. The cross-sectional study covered seven districts with 105 farmers interviewed during the wet and 45 others in the dry season. Up to 88 soil samples were collected and analyzed for soil texture, soil pH, organic matter and total Nitrogen, Phosphorus, Potassium, Calcium, Sodium and Magnesium. Likewise, 148 forage (105 fresh, 25 silage and 18 hay) tissues from 21 pasture species were collected and analyzed for nutritional values. Using a questionnaire, data on production costs and milk revenues were collected for cost-benefit analysis. Results showed that silage of Napier grass treated with molasses (10.2 MJ/kg) and hay of naturally established pastures (10.6 MJ/kg) had the highest metabolisable energy (ME) values, while the lowest (8.30 MJ/kg) was for star grass. Hay of star grass presented the highest level of crude protein (21.4%) with maize (corn) showing the lowest (9.38%). Digestibility of hay of naturally established mixed pastures was the highest (64.4%), followed by that of silage of Napier grass treated with molasses (62.0%), while star grass hay had the lowest (52.6%). With exception of silage made from maize, all the other six forms of silage had a good crude protein (CP) content. Regardless of the good CP content (≥9.9%), all silage untreated with additives was poor in quality since its ME was less than 9.9 MJ ME/kg and ration digestibility less than 67%. Nonetheless, feeding of silage and hay increased milk yield and farm productivity with a benefit-cost ratio of 5.5 and 2.7 for silage and hay respectively.

Effects of whole plant brown algae (Laminaria japonica) on zootechnical performance, apparent total tract digestibility, faecal characteristics and blood plasma urea in weaned piglets

ABSTRACTTwo trials were conducted with 48 newly weaned piglets (28 d old) each 8.6 ± 0.05 kg to study how Laminaria japonica plants (LJ) affect zootechnical performance, feed conversion and the apparent total tract digestibility (ATTD) of crude nutrients. All basal diets consisted of cereals, soybean meal, skim milk powder and premixes according to recommendations (no growth promoters or enzymes). For Trial 1, piglets from 16 litters (50% male-castrated, 50% female) were assigned to three treatment groups (n = 16) in a completely randomised block design. Groups received either 2.5% supplementation with sun dried (SD) or drum dried (DD) LJ powder or 2.5% of diatomaceous earth (control). For Trial 2, piglets from 12 litters received either 5% of diatomaceous earth (control) or one of three mixtures of diatomaceous earth + DD LJ powder (3.3%+1.7%, 1.7%+3.3% or 0.0%+5%; n = 12). Data collection included zootechnical performance, faecal consistency, blood plasma urea (Trial 1 and 2) and ATTD (Trial 2). Metabolisable energy (ME) of DD LJ and diets in Trial 2 was estimated using digestible nutrients. Statistical analysis included two-way ANOVA (treatment, block) and mixed linear regression. During both trials, LJ at dosages ≥2.5% significantly reduced feed:gain ratio compared to control (p ≤ 0.0001, = 0.01 for Trial 1, Trial 2) irrespective of the drying method. ATTD from Trial 2 significantly increased digestibilities of dry matter (DM) and crude ash (CA) (p ≤ 0.01) and significantly decreased digestibilities of organic matter and crude fibre in animals fed ≥3.33% DD LJ (p = 0.01). Fractional digestibility of the DD LJ resulted in limited ME of ~9.3 ± 2.5 MJ/kg DM. Dietary conversion ratios of ME and digestible DM of DD LJ diets from Trial 2 decreased linearly with increasing algal supplementation (R2 = 0.93, 0.94 and pslope = 0.002, 0.002 for MCR, DCR). In conclusion, dried LJ powder was included up to 5% into diets without impairing zootechnical performance. The improved feed conversion in the presence of LJ was partly due to slightly higher ME within the algae diets compared to control. However, piglets receiving LJ during Trial 2 needed significantly lower dietary ME and digestible DM to maintain growth performance. Thus, LJ exerted a performance enhancing effect on weaned piglets. The precise mode-of-action is yet unclear.

Effect of Different Energy Levels in Starter Ration Of Suckling Angus Calves on Blood Biochemical Parameters, Hormone Profile, Immune Response and Antioxidant Status

The objective of study was to evaluate the effects of energy level in starter ration on blood biochemical parameters, hormone profile, immune response and antioxidant status of calves. A total of eighteen angus calves were divided into three groups in such a way that each group had six calves. Three energy levels were {9 MJ/kg, low metabolizable energy (LME), 12.38 MJ/kg, medium metabolizable energy (MME) and 13.62 MJ/kg, high metabolizable energy (HME)}fed to experimental groups. Results showed that hemoglobin, red blood cells, hematocrit, thrombocytocrit and high-density lipoprotein was higher in HME diet (plessthan0.05). While, mean corpuscular volume, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, mean platelet volume and platelet distribution width was higher in MME diet as compared to HME diet plesstha0.05). Results of immunity revealed that IgA content were lowest in calves fed LME diet plesstha0.05). Calves received different energy level in the diet had no effect on IgG, IgM and C4 (P&gt;0.05). However, the calves on LME starter diet represented higher blood complement C3 contents plesstha0.05). It is concluded that blood metabolites were influenced by energy level in Angus calves.

Impacts of Graded Levels of Metabolizable Energy on Growth Performance and Carcass Characteristics of Slow-Growing Yellow-Feathered Male Chickens.

Simple SummaryInadequate feed inhibits the potential performance of birds, and giving birds excess nutrients or levels higher than the requirement reduces production profits and may lead to negative effects on performance. Although recently there has been an expanding market worldwide for slower growing chickens to meet the consumer demand for a better tasting meat, little effort has gone into optimizing their dietary nutrient levels. Using fiv e different dietary energy levels, this study evaluated the optimal requirement of dietary energy for maximal growth rate, feed:gain ratio, meat quality indices, and blood metabolites of a Chinese yellow-feathered breed.A dose-response study was conducted to investigate the metabolizable energy (ME) requirement for Lingnan chickens from 9 to 15 weeks of age. One thousand two hundred 8-week-old slow-growing yellow-feathered male chickens were allotted to five dietary ME levels (2805, 2897, 2997, 3095 and 3236 kcal/kg). The results revealed that the daily metabolizable energy intake increased (p < 0.01), whereas the feed intake and feed:gain ratio decreased linearly (p < 0.01) with the increment in dietary ME level. The final body weight and daily gain of the highest ME treatment tended (p > 0.05) to be greater than those obtained with the lower ME levels. The fat content in breast muscle showed a quadratic response (p < 0.05) to the increase in dietary energy level. The shear force values of breast muscle in the 2897, 3095 and 3236 kcal/kg treatments were lower (p < 0.05) than those of the 2997 kcal/kg treatment. In conclusion, among the tested ME levels, 3095 kcal/kg was adequate for feed intake, shear force, and plasma uric acid, and 3236 kcal/kg tended to increase the body weight, body gain, and feed conversion ratio of Lingnan males between 9 and 15 weeks of age; further studies are still required for testing higher levels.

Effects of lactic acid bacteria inoculation in pre-harvesting period on fermentation and feed quality properties of alfalfa silage.

ObjectiveTo develop the fermentation quality and chemical composition of alfalfa (Medicago sativa Lam.) silage, plants were inoculated with different lactic acid bacteria (LAB) strains at field 24 hours before harvest.MethodsThe treatment groups were as follow: silage without additive as a control and inoculated with each strains of Lactobacillus brevis (LS-55-2-2), Leuconostoc citerum (L. citerum; L-70-6-1), Lactobacillus bifermentans (L. bifermentans; LS-65-2-1), Lactobacillus plantarum (L. plantarum; LS-3-3) and L. plantarum (LS-72-2). All the silages were stored at 25°C. Parameters such as pH, microorganism and volatile fatty acid contents, crude protein, neutral detergent fiber, acid detergent fiber, net gas, metabolizable energy, organic matter digestibility, dry matter intake and relative feed value were measured to determine fermentation quality, chemical compositions and relative feed value of alfalfa silages.ResultsSignificant differences were found among the control and treated groups in terms of pH and microorganism contents at all opening times and crude protein, net gas, metabolizable energy and organic matter digestibility of final silage. The pH values ranged from 4.70 to 5.52 for all treatments and control silage had the highest value of overall treatments at T75d silages. Volatile fatty acid of silages was not influenced significantly by inoculations. However, lactic acid content of L. bifermentans (LS-65-2-1) was higher than the other treatments. The highest metabolizable energy and organic matter digestibility were recorded from L. citerum (L-70-6-1) inoculation. In addition, no significant differences were found among treatments in terms of neutral detergent fiber, acid detergent fiber, dry matter intake and relative feed value.ConclusionAmong the treated LAB isolates, L. bifermentans came into prominence especially in terms of organic acid composition and quality characters of silages.

Methane production and microbial protein synthesis in adult sheep fed total mixed ration as mash and as complete feed block

Sixteen rams in two groups were fed ad libitum total mixed ration as mash (TMRm) and as block (TMRb) for 90 days, and methane (CH4) emission was estimated by standard SF6 tracer technique. Feed samples were also incubated in vitro for calculating CH4 emission. In vitro incubation revealed lower (P < 0.05) gas production and CH4 from TMRb. Rams fed on TMRb consumed higher (P < 0.05) dry matter (DM), digestible crude protein (CP) and metabolizable energy (ME). The digestibility of nutrients was similar between the groups except for CP, which was higher in TMRb. The CH4 emission per unit digestible DM and organic matter intake was lower (P < 0.05) from TMRb, resulting in lower energy loss as percentage of dietary energy and higher ME intake as compared to TMRm. Microbial protein synthesis (MPS) as assessed from urinary purine derivatives was higher in TMRb. The rams on TMRb also exhibited improved N utilization compared to TMRm. Post-feeding (4 h) ruminal attributes in TMRm showed higher total N and lower acetic and butyric acid with an increased total ciliate protozoa and entodinia population. It may be concluded that TMR offered in block form emits less CH4 and saves ME, besides improving CP digestibility, MPS and N utilization.

Nutritive characteristics of perennial ryegrass cultivars: have they changed over time?

Improvement in nutritive characteristics resulting from breeding perennial ryegrass (PRG) cultivars used in Australia from the 1970s to the present day was quantified in a grazed field experiment in south-western Victoria. The experiment was sown in May 2014 with measurements undertaken over 3 years. The experiment contained 36 PRG treatments (cultivar–endophyte combinations), which were replicated four times, with herbage nutritive characteristics measured at each grazing. The treatments differed in estimated metabolisable energy (ME), crude protein and neutral detergent fibre (NDF) concentrations at each harvest date. The decade of cultivar release had little effect on the ME or the NDF concentration of the cultivars released from 1970s onward. Early season diploids had a lower ME concentration than did later-maturing diploid cultivars (11.0 vs 11.4 MJ/kg DM), predominantly due to a lower ME concentration in late spring and early summer (10.3 vs 11.1 MJ/kg DM). The tetraploid cultivars had a higher ME concentration (11.8 vs 11.4 MJ/kg DM) and a lower NDF (480 vs 505 g/kg DM) concentration than did the mid- and late-season diploid cultivars. These differences are likely to be of economic importance at the farm level.

High lipid perennial ryegrass growth under variable nitrogen, water and carbon dioxide supply

A novel strategy to increase the metabolisable energy content of pasture species has been the development of a GM technology (‘High metabolisable energy’ or HME), which when expressed in the leaves of perennial ryegrass, increases leaf lipids up to 6-7% of DW (approximately double ‘normal’ levels). Remarkably, increased rates of photosynthesis and growth also occur in these plants. The industry strategy is to perform field trials overseas to establish the value proposition for New Zealand. Here, results are presented from preliminary growth-chamber pot trials which reveal the influence of the HME technology on perennial ryegrass growth under different levels of N, H2O and CO2 supply. HME increased perennial ryegrass growth under high N supply, limiting and non-limiting H2O supply, and with ambient and elevated CO2 supply. Possible HME growth mechanisms and their practical implications are discussed. Progress on the 2017 field trial in the USA using offspring from the HME crossing programme is also discussed.

English

This study investigated the effect of cutting height (30 and 100 cm) on chemical composition and in vitro digestibility in field-grown Acacia angustissima (Mill.) Kuntze. (Prairie acacia), Leucaena pallida Britton &amp; Rose (guaja) and Mimosa scabrella Bentham. (bracatinga) legumes and their value in supplementing a basal diet of Chloris gayana Kunth. (Rhodes grass). Cutting height did not affect major chemical composition. Crude protein (CP) was highest in A. angustissima and lowest in M. scabrella, while neutral detergent fibre (NDF) and acid detergent fibre (ADF) were highest in M. scabrella. Degradation parameters were greater at 100 cm cutting height. L. pallida showed high in vitro organic matter digestibility but A. angustissima had the highest metabolisable energy. Addition of A. angustissima, L. pallida and M. scabrella to the basal diet increased improved the nutritional value and increased the CP content from 8.4 to 19.8% and 18.1 and 16.1%, respectively. Cutting height of A. angustissima, L. pallida and M. scabrella had no effect on their nutritional value. Their other functions and benefits will determine choice of cutting height as management practice when used on farms. Key words: Legume trees, cutting height, chemical composition, in vitro degradability. &nbsp

Effects of dietary supplementation of choline and carnitine on growth performance, meat oxidative stability and carcass composition of broiler chickens fed diets with different metabolisable energy levels

ABSTRACT1. This study was conducted to investigate the effects of two lipotropic factors (choline and carnitine) on growth performance, oxidative stability of leg and breast muscles and carcass characteristics in broiler chickens fed diets differing in metabolisable energy (ME) levels.2. A total of 540 one-d-old Ross 308 broiler chicks were allotted to 9 experimental diets, including three ME levels (control, or 0.42 or 0.84 MJ/kg higher ME) and three types of supplemental lipotropic factors (control, 1000 mg/kg of choline or 100 mg/kg of carnitine) as a 3 × 3 factorial arrangement of treatments. Average daily feed intake (ADFI), average daily gain (ADG) and feed conversion ratio (FCR) were recorded during the starter (1–14 d of age), grower (15–28 d of age) and finisher (29–42 d of age) periods.3. Results showed that the increase in dietary ME level had no impact on ADFI during the starter and grower periods. In the finisher period, increasing dietary ME decreased (P < 0.001) ADFI. Raising dietary ME level by 0.84 MJ/kg resulted in the greater ADG during the grower (P < 0.05) and finisher (P < 0.001) periods. Moreover, an improvement in FCR was observed with feeding the +0.84 MJ/kg diet. Dietary supplementation of lipotropic factors improved FCR values in birds fed the control and +0.84 MJ/kg diets during the grower and finisher periods (P < 0.01).4. Dietary supplementation of both choline and carnitine increased (P < 0.05) moisture content of leg muscle, although malondialdehyde content of leg muscle was decreased (P < 0.01) in the presence of both lipotropic factors. Dietary supplementation of carnitine decreased (P < 0.01) leg fat content, and this effect was more obvious with higher ME levels, giving a significant ME × lipotrope interaction (P < 0.05). Higher dietary ME level (+0.84 MJ/kg) reduced (P < 0.05) protein content of breast muscle, but this factor was increased (P < 0.05) by dietary supplementation of choline.5. Although dietary ME level had no marked effect on carcass yield and internal organ weight, supplemental choline increased (P < 0.01) carcass yield.6. The results from this trial indicated that dietary supplementation with lipotropic factors can improve feed efficiency in high energy diets. In addition, oxidative stability of leg/breast muscles was improved as a result of dietary supplementation with choline or carnitine.