Ruminant Feed Research Articles

Harnessing Tanzania's Rangelands to Mitigate Methane Emissions from Livestock Enteric Fermentation

Methane emissions from livestock being a major contributor to climate change as methane possesses more global warming potential than carbon dioxide, exacerbating the issue. Therefore, reducing methane emissions is crucial in addressing climate change and promoting sustainable agriculture. Tanzania is endowed with a large livestock population and vast rangelands. The resultant enteric methane emissions share in the agriculture sector was estimated to be 39.71% in 2014. This data suggests that interventions to lower methane emissions in agriculture sectors need to focus on livestock especially ruminants to provide significant reduction. The study found that normalisation of emissions can be facilitated by a set of measures, namely: a) increasing the energy content or quality of ruminant feed to reduce the intensity of methane production in the gut; b) addressing existing problems in pasture use, including deforestation, uncontrolled burning, overgrazing, water shortages and invasive species; c) improving feeding in combination with other livestock management practices to achieve the expected productive effect while reducing methane emissions.

Evaluating complete silage for goat feeding in Gorontalo, Indonesia

Forage shortages and inconsistent quality in developing countries pose significant challenges to the small ruminant sector. Feeding ruminants with conserved forages is crucial to address this issue and ensure successful ruminant management in developing countries. The use of sorghum crops mixed with grasses as fermentation feed has gained thought because of its high protein efficiency, relatively high digestible energy, and total digestible nutrients. Therefore, this study aimed to determine feed intake, nutrient digestibility, and growth performance in Gorontalo local goats fed complete silage with varying levels of mixed concentrations of sorghum straw with grasses. Sixteen male Gorontalo local goats were preferred from the local area and randomly divided into four groups using a completely randomized design (CRD). Over 84 days, four different complete silage diets (T1, T2, T3, and T4) were given to goats. The goats' daily nutrient intake, digestibility, and growth performance were analyzed. The T1 diet consisted of 30% grass and 60% sorghum straw, the T2 diet included 20% grass and 70% sorghum straw, the T3 diet contained 10% grass and 60% sorghum straw, and the T4 diet had no grass and 90% sorghum straw. The study found that the dry matter intake (DMI) of goats ranged from 330.2 to 335.1 g/day, approximately 3% of their body weight. The digestibility values of dry matter, crude protein, crude fat, neutral detergent fiber, acid detergent fiber, and energy decreased as the amount of sorghum straw in the silage rations increased. The average daily gain (ADG) (gr/day) in T1, T2, T3, and T4 was affected, with T1 showing the highest ADG (43.2) and T4 showing the lowest (40.3). The Feed Conversion Ratio (FCR) value was also influenced, with T1 and T2 showing the best FCR (7.8 and 7.7) and T3 showing the worst (8.2). Based on these findings, it is recommended to limit the amount of sorghum straw to 60%-70% in complete silage for local goats in Gorontalo, especially in tropical areas where goats are common and sorghum is readily available.

EVALUATION OF LAND SUITABILITY FOR ANIMAL FEEDING IN THE BOBANE IGO AREA, SOUTH JAILOLO DISTRICT, WEST HALMAHERA DISTRICT

Feed This research aims to evaluate the suitability of land for animal feed in the Bobane Igo area, South Jailolo District, West Halmahera Regency with an area of 1684.7 ha. The types of plants studied were lamtoro, calliandra, legumes, and turi. The methods used are field surveys, soil data analysis and research data analysis with matching method. The total area of the Bobane Igo area is 1684.7, indicating that the Bobane Igo area has high potential for developing ruminant animal feed. A total of 1023.4 ha (61%) for calliandra, 1154.2 ha (68%) for legumes. It is hoped that the development of animal feed crops in the Bobane Igo area can support food security and increase the income of breeders in the area.

KOMPOSISI BOTANI HIJAUAN ALAMI DI AREAL PERKEBUNAN KELAPA DALAM SEBAGAI PAKAN TERNAK RUMINANSIA DI KECAMATAN TANIWEL KABUPATEN SERAM BAGIAN BARAT

ackground: The need for and provision of forage is achieved by considering the continuous provision of forage in both quantity and quality. One of the efforts to develop animal husbandry that can be carried out is to utilize forage for livestock in deep coconut plantations. This research aims to determine the botanical composition of natural forage in coconut plantation areas as feed for ruminants in Taniwel District, West Seram Regency. Method s : This research uses a purposive sampling method. The data used in this research is based on secondary data and primary data. Results : The research results showed that the botanical composition results were 63.18% grass, 26.30% weeds and 10.52% legumes. Co nclusion: Based on the research results, it is necessary to eradicate pest plants (weeds) for forage and plant superior forage to increase the need for feed for ruminant livestock. The availability of forage can still meet the need for animal feed in Taniw el District, West Seram Regency

Addition To Green-Based Feed Preparations With Fermentation Technology Innovation Good Ruminant Feeding Practices

Improving ruminant feed quality is an important factor in increasing livestock productivity and health. To improve feed quality, accompanying forage-based ruminant feed preparation with fermentation technology innovation is the focus of community service activities. Accompanying forage-based ruminant feed preparations with a fermentation technology approach is intended to optimize the nutrition and microbial content in the feed, thereby increasing the availability of nutrients and digestion of livestock, with impact factors on growth, animal health, and milk production. Fermentation technology innovations can improve feed quality by increasing nutritional content, reducing anti-nutritional ingredients, and increasing nutritional availability for livestock without depending on or being influenced by changes from the rainy season to the dry season.

Estimation of ruminal digestibility and fermentation characteristics of coffee pulp: A meta-analysis of in vitro experiments

Integrating various studies with statistical methods can be used by applying a meta-analysis method. The objective of this meta-analysis was to evaluate the effect of coffee pulp as ruminant feed on in vitro digestibility and rumen fermentation characteristics. The database was developed from six related articles containing 25 studies, collected from Scopus and Google Scholar. The parameters integrated were in vitro dry matter digestibility (IVDMD), in vitro organic matter digestibility (IVOMD), pH value, total volatile fatty acids (VFA), NH3 and total protozoa. The data were analyzed using a mixed model methodology. The level of coffee pulp was considered as a fixed factor and the different studies as a random effect. The results revealed that coffee pulp addition had a significant quadratic effect to enhance IVDMD (P<0.01) and a significant linear effect to decrease total VFA (P<0.05). However, coffee pulp addition did not significantly affect (P>0.05) on IVOMD, pH, NH3 and total protozoa. In conclusion, coffee pulp can be used as an alternative feedstuff due to its good digestibility in the rumen. Nevertheless, it should be applied in the right amount to avoid negative effects on animal performance.

Nilai Pemanfaatan Limbah Kelapa Sawit untuk Pakan Ternak (Studi Kasus Pakan Ruminasia)

The issue of feed has a large proportion of the sustainability of livestock businesses. On the other hand, palm fronds as post-harvest agricultural waste and bran as post-processing waste have not been utilized optimally. Even though the nutritional content contained in it is quite high. Agricultural and plantation waste by-products have good potential for use as animal feed. In order to guarantee safety and suitability, further processing and analysis is needed. Processing of raw materials is carried out in a combination (physical, chemical and biological). Preparation of feed formulations using Pearson's Quadrilateral Method. Testing is carried out in laboratories that consistently apply ISO/IEC 17025: 2017 from the National Accreditation Committee (KAN), namely the East Java Province Animal Husbandry Service. The standard test results refer to SNI 3148-2:2017 concerning Concentrate Feed for Fattening Beef Cattle. Ruminant animal feed that meets SNI 3148-2:2017 includes levels of ash, crude fat, phosphorus, TDN, aflatoxin and crude fiber. Meanwhile, the nutritional content that is close to SNI is crude protein and aNDF. The test results also showed that the content did not meet SNI, including water and calcium content. Meanwhile, fish feed (pellets) that meet SNI 01-4087-2006 contain 3 types of content including ash, crude fat and aflatoxin. The types of content that do not meet SNI are crude protein, crude fiber, phosphorus, buoyancy and pellet diameter. The estimated cost of making ruminant feed is IDR 5,986 per kilogram. Cost analysis is relevant to feed quality and daily requirements without reducing nutritional value. Further research is needed to ensure that artificial feed is more cost efficient than conventional feed.

Effect of hydroxypropyl methylcellulose (HPMC) hard capsules on in vitro rumen fermentation kinetics of commonly used feeds in ruminant feeding.

Accurate dosing of feed additives is often required to evaluate their effects on rumen fermentation. This can be done using soluble but nonfermentable hydroxypropyl methylcellulose (HPMC) hard capsules. The aim of the study was to evaluate the effect of HPMC hard capsules on the extent and rate of in vitro gas production in eleven feeds. Six high-fibre feeds and five concentrates, were weighed into syringes either directly or into HPMC capsules and incubated anaerobically in 30mL buffered rumen fluid at 39°C. Data obtained from gas production measurements were fitted using the Gompertz model to obtain kinetic parameters for gas production. HPMC hard capsules had no effect on the gas production of the blank sample and concentrate feeds. In contrast, high-fibre feeds weighed in HPMC showed a significant decrease (p < 0.05) in total gas production and gas produced within 24 h of incubation. The use of HPMC hard capsules was found to be inappropriate for determining gas production kinetics because fermentation subsides at a certain point when peak fermentation is reached (at TMFR), resulting in a decrease in both total potential gas production and gas production within 24 h of incubation. This is particularly evident when high-fibre feeds are incubated.

Nilai Nutrien dan Kecukupan WSC Berbagai Hijauan Sebagai Sumber Pakan Silase

Cultivation of forages from graminae and legumes is an alternative source of fiber feed to meet basic living needs and ruminant livestock production. This research aims to assess the nutritional and WSC content of various forages as indicators and considerations in making silage. The research used a completely randomized design with 5 treatments with 4 replications. Regarding the treatment of forage types, namely A = elephant grass; B = Gama Umami; C= Mexican Grass; D= Odot grass; D = Indigofera beans. The research parameters are crude protein (%), crude fat (%), dry matter (%), ash, crude fiber (%), water-soluble carbohydrates (%), and NDF and ADF content (%). The results showed that different types of forage had a significant effect (P&lt;0.05) on the nutritional value and WSC content. The research conclusion was that Indigofera legumes and odot grass had the highest WSC content, namely 4.59% and 4.49%. Furthermore, indigofera legumes and odot grass also produce the lowest NDF and ADF values compared to other treatments, so they have the potential to be used as raw materials for making silage to support the availability of ruminant feed

PRODUKSI DAN KANDUNGAN NUTRIEN HIJAUAN RUMPUT Pennisetum purpureum cv Mott, DENGAN PEMBERIAN PUPUK ORGANIK CAIR HASIL VERMICOMPOSTING LIMBAH SAPI POTONG

Fertilization is a very important effort for Dwarf Elephant Grass (Pennisetum purpureum cv Mott) to achieve forage production and high nutritional quality following its potential. This research aims to determine the yield of dry matter, crude protein content, and crude fiber of Dwarf Elephant Grass by application of liquid organic fertilizer (LOF) resulting from vermicomposting of beef cattle waste. The research was conducted at the Field Laboratory of Forage Crop, and the Ruminant Animal Nutrition and Feed Chemistry Laboratory, Faculty of Animal Husbandry, Padjadjaran University from January to June 2018. The research method used was the experimental method with a Completely Randomized Design using 3 treatments, namely P1 (5,000 L per Ha), P2 (10,000 L per Ha), and P3 (15,000 L per Ha), and 6 replications. Data were processed by analysis of variance and continued with Duncan's Multiple Range Test. The results showed that giving LOF increased the production, increased the content of crude protein, and decreased the crude fiber content of Dwarf Elephant Grass forage. Giving LOF from vermicomposting beef cattle waste at a dose of 15,000 L per Ha resulted in the highest forage dry matter yield (1,925 kg per Ha), one-time cutting at dry season, and the best nutrient content seen from the crude protein content (13.95%) and crude fiber content (28.53%).

Use of sugarcane crop residue silage with different levels of inclusion in dual-purpose cow diets

In the sugar cane production chain, different byproducts are generated that can be used in animal feed. Their conservation in the form of silage is an important contribution towards improving animal production in tropical regions. The objective was to evaluate the inclusion of different levels of silage from sugarcane crop residues in the diet of dairy cows in a family farming system. Nine lactating cows were used in a 3x3 Latin square design in triplicate and means were compared using the Tukey test. The treatment sequences were randomly assigned with periods of 14 days. Three treatments were formulated that included feed of mixed native grasses, supplemented with sugarcane top silage with different inclusion levels (2 kg/DM for T1, 4 kg/DM for T2 and 6 kg/DM for T3), along with commercial concentrate and corn silage. Milk production, its chemical composition, and the efficiency of feed utilization were evaluated. The average milk production, fat content and crude protein were, respectively, 9.38kg/cow/day, 32.6 and 340.0 g/cow/day. No differences were detected (P&gt;0.05) for any of the variables evaluated, but the inclusion of 6 kg of sugarcane residues silage improved the animals' feed efficiency. Therefore, sugarcane top silage is a viable alternative for feeding ruminants.

The use of small diameter nozzles in temperature-controlled hemp oil extraction allows high oil yields and good quality residual hemp cake feed.

The use of two nozzle diameters (6 and 8 mm) in a cold (50°C) hemp seed oil extraction process was evaluated in terms of extraction efficiency, and chemical composition and in vitro fermentation characteristics of the residual cake. Seeds of the varieties Futura 75 and Uso 31 were pressed using a mechanical press with a cooling device. Five pressings were carried out for each variety and nozzle size, the functional parameters of the extraction processes were recorded, and sample of the residual cakes (n = 20) were analyzed. The 6 mm nozzle determined a higher oil yield (+4%) with a limited increase in temperature in the pressing chamber and in the oil (on average + 3°C compared to the 8 mm nozzle). A lower oil yield and consequently a higher fat content in the corresponding cake was observed when using the 8 mm nozzle. Despite the similar fat content, the two varieties had different oil yields and different residual cake compositions. The gas production kinetic of cakes was influenced by variety but little by nozzle size. Overall, the use of a smaller nozzle in a temperature-controlled extraction process can be a useful option to increase hemp oil yield while maintaining good fermentation characteristics of the residual cakes as ruminant feed.

Lactic Acid Bacteria and Formic Acid Improve Fermentation Quality and Beneficial Predicted Functional Characteristics in Mixed Silage Consisting of Alfalfa and Perennial Ryegrass

The purpose of the present study was to investigate the effect of additives on the fermentation properties of ensiled mixed alfalfa and perennial ryegrass silage in the karst terrain of Southwest China. A mixture of alfalfa and perennial ryegrass was ensiled at a ratio of 3:7 using three experimental treatments: (1) CK (without additives) and distilled water (5 mL kg−1 fresh weight (FW)); (2) FA and formic acid (88%) (5 mL kg−1 FW); and (3) LAB combined with the application of Lactiplantibacillus plantarum and Lentilactobacillus buchneri (2 × 107 cfu/g FW). All samples were packed manually into polyethylene bags, and three polyethylene bags from each treatment were sampled on days 7, 15, and 45. The findings demonstrated that the pH values of all the mixed silages gradually decreased during ensiling. The lactic acid (LA) and acetic acid (AA) contents increased gradually with ensiling time and peaked after 45 days of ensiling. After 45 days of ensiling, the FA and LAB groups effectively preserved the nutrient content of the mixed silage, which presented a reduced neutral detergent fiber and acid detergent fiber content (p &lt; 0.05) and higher water-soluble carbohydrate content (p &lt; 0.05) than the CK group. The fermentation quality of the mixed silages in the FA and LAB groups improved, as indicated by higher (p &lt; 0.05) LA contents and lower (p &lt; 0.05) pH and ammoniacal nitrogen contents after 45 days of ensiling compared to those in the CK group. As fermentation progressed, the abundance of harmful microorganisms (Hafnia obesumbacterium, Enterobacteriaceae, and Sphingomonas) and beneficial microorganisms (Lactiplantibacillus and Lentilactobacillus) decreased and increased, respectively. In addition, compared to those in the CK group, the FA group had higher abundances of “lipid metabolism” and “biosynthesis of antibiotics” and lower abundances of “membrane transport”. Briefly, the results of this study suggest that the incorporation of FA and LAB additives could improve the quality of fermented mixed silage, and that FA is better than LAB. This information is useful for combining forage resources to satisfy the requirements for high-protein feed and for manufacturing ruminant feed annually.

Novel quality feed from a wasted resource: measuring the nutritional value of low-glycoalkaloids potato haulm in sheep

This study evaluated the potential of low-glycoalkaloid potato haulm (LGPH) as a high-quality feed for ruminants. The low-glycoalkaloid potato plants were grown in a net house following standard agricultural practices. Dehaulming was performed a fortnight before the harvest of the tubers, as commercially practiced. Four healthy female lambs (aged 4 months) were employed in a 4×4 Latin square feeding experiment design. The lambs were fed with either a maintenance diet consisting of 73% roughage (control), or treatment diets with supplementation of 10% (P10), 15% (P15), and 20% (P20) LGPH on a dry matter (DM) basis for a period of 21 days, including 14 days of adaption and 7 days of sampling. Refusals and feces were collected for 6 days and pooled followed by a 24 h urine collection on the 7th day. On the 6th day, an hour after morning feeding, blood, and rumen liquid samples were collected. All the samples were analysed, and the data generated were analysed using ANOVA with diet and period as fixed effects and sheep as a random effect. Orthogonal contrasts were used to detect linear and quadratic effects of LGPH in the diet. Linear or polynomial equations were produced to extract the nutrient digestibility and metabolizable energy (ME) of LGPH. No toxicological clinical signs were observed, and the haematology profiles were normal throughout the trial. LGPH did not affect the daily intake of nutrients and energy. However, the apparent digestibility of DM, organic matter (OM), crude protein (CP), and gross energy increased (P= 0.01) linearly (P&amp;lt; 0.01) with supplementation of LGPH in the diet. The inclusion of LGPH had a quadratic effect on neutral detergent fiber (NDF) digestibility (P= 0.027), reaching a peak of 54.8 % at 12.3 % LGPH supplement on a DM basis. The N retention in lambs fed with the P20 diet was nearly twice that of the control diet (P= 0.032; 19.1 vs. 10.2 g/d). The computed digestibility values of DM, OM, CP, and NDF for LGPH were 76.1, 79.7, 84.2, and 72.1 %, respectively, and ME was 2.62 Mcal/kg DM. Conclusively, by significantly reducing the glycoalkaloids’ content in potato haulm, we can safely repurpose the currently wasted foliage as a new source of high-quality roughage feed for ruminants, equivalent to alfalfa hay, without imposing any additional environmental burden. However, further research is necessary to assess impact of LGPH on growth performance, and milk productivity before practical application on commercial farms.

Bioactive metabolites of Asparagopsis stabilized in canola oil completely suppress methane emissions in beef cattle fed a feedlot diet.

Asparagopsis taxiformis (Asparagopsis) has been shown to be highly efficacious at inhibiting the production of methane (CH4) in ruminants. To date, Asparagopsis has been primarily produced as a dietary supplement by freeze-drying to retain the volatile bioactive compound bromoform (CHBr3) in the product. Steeping of Asparagopsis bioactive compounds into a vegetable oil carrier (Asp-Oil) is an alternative method of stabilizing Asparagopsis as a ruminant feed additive. A dose-response experimental design used 3 Asp-Oil-canola oil blends, low, medium, and high Asp-Oil which provided 17, 34, and 51mg Asparagopsis derived CHBr3/kg dry matter intake (DMI), respectively (in addition to a zero CHBr3 canola oil control), in a tempered-barley based feedlot finisher diet, fed for 59 d to 20 Angus heifers (five replicates per treatment). On four occasions, live weight was measured and CH4 emissions were quantified in respiration chambers, and blood, rumen fluid, and fecal samples were collected. At the end of the experiment, all animals were slaughtered, with carcasses graded, and samples of meat and edible offal collected for testing of consumer sensory qualities and residues of CHBr3, bromide, and iodide. All Asp-Oil treatments reduced CH4 yield (g CH4/kg DMI, P = 0.008) from control levels, with the low, medium, and high Asp-Oil achieving 64%, 98%, and 99% reduction, respectively. Dissolved hydrogen increased linearly with increasing Asp-Oil inclusion, by more than 17-fold in the high Asp-Oil group (P = 0.017). There was no effect of Asp-Oil treatment on rumen temperature, pH, reduction potential, volatile fatty acid and ammonia production, rumen pathology, and histopathology (P > 0.10). There were no differences in animal production and carcass parameters (P > 0.10). There was no detectable CHBr3 in feces or any carcass samples (P > 0.10), and iodide and bromide residues in kidneys were at levels unlikely to lead to consumers exceeding recommended maximum intakes. Overall, Asp-Oil was found to be safe for animals and consumers of meat, and effective at reducing CH4 emissions and yield by up to 99% within the range of inclusion levels tested.

Chemical Composition and In Vitro Nutritive Evaluation of Pomegranate and Artichoke Fractions as Ruminant Feed

The aim of this work was to assess the chemical composition and in vitro ruminal fermentation of samples (n = 3) of pomegranate (peels (PPs) and seeds (PSs)) and artichoke (hearts (AHs) and stems (ASs)) wastes. Dried orange pulp (DOP) and tomato pomace (TP) were used as reference feeds. All wastes had low dry matter (DM; lower than 33.0 and 12.0% for pomegranate and artichoke, respectively). The DM of pomegranate fractions was rich in sugars (&gt;42.0%) and contained low protein (&lt;8.0%) and neutral detergent fiber (NDF; &lt;27.0%), whereas that of both artichoke fractions had high protein (&gt;18.0%) and NDF (&gt;36.0%) and low sugars content (&lt;9.2%). Pomegranate seeds were more rapidly and extensively fermented in vitro than PPs, but both were less degradable and contained less metabolizable energy (ME) than DOP (7.43, 11.0 and 12.5 MJ ME/kg DM, respectively). Although AHs were more rapidly fermented and produced more volatile fatty acids (VFAs) than ASs, both had lower ME content than TP (9.50, 7.25 and 12.5 MJ ME/kg DM). The analyzed wastes had lower ME content than other by-products, but they were extensively fermented by ruminal microorganisms and could be used as ruminant feeds.

Investigating the presence and antibiotic susceptibilities of Escherichia coli O157 and Listeria monocytogenes in ruminant feces and feed in Balıkesir province

The aim of this study is to determine the presence, virulence factors, and antibiotic susceptibilities of E. coli O157 and L. monocytogenes in ruminant feces and feed. This study was carried out for the first time in Balıkesir province. Feces, pellet feed, and silage samples were analyzed simultaneously for E. coli O157 and L. monocytogenes using feces of one gram and feed of twenty-five grams according to ISO 16654:2001/Amd 1:2017 and ISO 11290-1, respectively. 38 (38%) E. coli O157 strains were isolated and identified from a total of 100 ruminant feces. A total of 3 (3%) E. coli O157:H7 strains were detected by PCR from one hundred ruminant fecal samples. In the study, resistance to antibiotics increased, especially in E. coli O157 isolates. In this study, enterohaemolysin was the predominant virulence factor among the E. coli isolates, and it was thought that it was important for pathogenesis. The Sxt1 gene was higher than the Stx2 gene. A total of 24 L. monocytogenes strains were isolated from a total of 100 ruminant fecal samples and 50 silage samples. Three of these strains were isolated from silage samples taken from the farms, where L. monocytogenes was isolated from sheep feces. As a result, poor quality silage could be an important source of infection for listeriosis in Balıkesir province. Epidemiologically, poor quality silage was thought to be one of the sources of listeriosis. It was thought that ruminant feces played an important role as a reservoir in the spread and transmission of E. coli O157. The antibiotic resistance status of E. coli O157 and L. monocytogenes isolates should be monitored with epidemiological studies.

Identification of macroalgae from the West Coast of Sulawesi and potential utilization as ruminant feed sources

The use of macroalgae as a ruminant feed is being widely developed due to its rich nutritional content and the presence of anti-methanogenic substances that may be able to reduce the formation of methane gas in ruminants. Macroalgae are cultivated and not cultivated; the species are diverse and grow in groups throughout Indonesian waters. This study aims to identify macro algae morphology that is easily found in the waters of the West Coast of Sulawesi and its potential use as a source of ruminant feed. Macro alga samples of cultivated and non-cultivated algae were collected from farmers and fishermen from the West Coast of Sulawesi, then continued with morphological identification. Several related articles and previous research obtained data regarding nutritional content using proximate analysis (protein, lipid and ash) and its potential use as a feed source. Research shows several macroalgae species that are easily found in the waters of the west coast of Sulawesi, namely macroalgae cultivated Gracilaria sp, Eucheuma denticulatum, Eucheuma cottonii, and Caulerpa sp. In contrast, the non-cultivated ones are Sargassum sp, Padina australis, Halymenia sp, Halimynea sp, and Caulerpa sp. Of the eight species, It is nutrient-rich and may be utilized as a source of feed for ruminants in the form of pure or extracts, but the proportion of macroalgae in the diet must be taken into account.

Agro-industrial by-products as ruminant feed: Nutritive value and in vitro rumen fermentation evaluation.

In recent years, agricultural by-products have generated increasing interest as ruminant feed. In a completely randomized design with five experimental treatments, this in vitro study investigated the nutritional value of citrus pulp and onion peel as alternative feed for ruminants and their effects on rumen fermentation, digestibility, and gas production. The first group was the control (50% grass hay/50% concentrate mixture). The other four treatments represented citrus pulp and onion peel at inclusion levels of 10 and 20%, replacing the expensive, high-quality feed ingredients such as the concentrate mixture. The chemical composition showed that citrus pulp is an energy-rich material that could be included up to 20% to replace part of the concentrate in a mixed diet without any adverse impacts on rumen fermentation parameters. The onion peels were rich in fiber and minerals. Their inclusion in the diet of over 10% had detrimental effects on rumen fermentation. The inclusion of either citrus pulp or onion peel in the diet did not have the potential to reduce enteric methane production. In conclusion, citrus pulp showed promising results as a new feed for ruminants. It was effective when included in up to 20% of a ruminant diet, replacing the concentrate mixture.

DIFFERENT MAIZE SILAGE CULTIVARS WITH OR WITHOUT UREA AS A FEED FOR RUMINANT: CHEMICAL COMPOSITION AND IN VITRO FER-MENTATION AND NUTRIENT DEGRADABILITY

This study compared forage yield and agronomic characteristics of 9 maize cultivars (Pioneer 30N11, Pioneer 4444, Pioneer 30K08, SC-128W, SC-166Y, SC-78Y, TWC-324W, TWC-368Y and TWC-321W) ensiled with or without urea as for ruminants on in vitro ruminal fermentation characteristics and nutrient degradability. A factorial randomized complete block design was used. Pioneer 30N11 and Pioneer 4444 showed the greatest silage forage yield, ear weight, and plant height. The chemical composition of maize silage cultivars without urea revealed that Pioneer 30K08 had the greatest (P 0.001) crude protein (CP) content (127 g/kg), while the lowest CP content (89 g kg) was observed with SC-78Y. CP content ranged from 118 to 156 g/kg when urea was added to the maize silage cultivars. The neutral detergent fiber, acid detergent fiber, and acid detergent lignin contents recorded the highest values (P0.01) in TWC-324W, SC-128W and SC-78Y. Urea treatment of different cultivars affected (P 0.05) the concentrations of CP, ether extract (EE), non-structural carbohydrates (NSC), and fibers. Urea treatment increased CP and EE in all cultivars and increased or decreased truly degraded dry matter (TDDM), truly degraded organic matter (TDOM), protozoa, ammonia and methane (P 0.05). Overall, Pioneer 30N11, Pioneer 4444 and Pioneer 30K08 showed the greatest forage yield and nutritive value as a feed for ruminants.