Designing a Biogas Plant for an Educational and Scientific Livestock Complex

To design biogas plants, it is necessary to have accurate data about the properties and biogas productivity of the available substrates. Reference data should not be used because the performance of the same substrate can vary significantly. In this research,chicken, horse, sheep and rabbit manure from one of the farms inthe Belgorod region of Russia were analyzed, and the parameters of a biogas station for the processing of this raw material were calculated.The biogas yield of the substrates was determined using the Hohenheim Biogas Yield Test. It was found that the specific biogas yield from the droppings of broilers, laying hens, rabbits, sheep, and horses, and from corn silage were, respectively, 456, 363, 390, 189, 116 and 618 ml/g оDM. The methane content in the biogas was 58.00, 58.50, 57.00, 62.00, 65.00 and 53.60%, respectively. In most cases, the obtained results differed significantly from the data presented in publications of other researchers and reference books.The biogas plant parameter calculations were made according to generally accepted equations, taking into account the characteristics of the studied substrates. Based on the results, it can be concluded that to dispose of the animal excrement of this farm, it is necessary to build a biogas plant with a bioreactor of volume 102.2 m3 and an engine with a power of 12 to 31 kW. The planned output of electric and thermal energy would be 246.19 and 410.27 kWh/day, respectively. Keywords: Hohenheim Biogas Yield Test, rabbit manure, horse dung, sheep manure, chicken droppings, biogas yield of substrates

Abstracts of the 45th Symposium on Cuniculture, ASESCU

The 45th Congress of the Spanish Association of Cuniculture (ASESCU), co-organised by the Spanish Association of Cuniculture (ASESCU) and Grupo Editorial Agrícola-Henar Comunicación Agroalimentaria, was online held on 6th and 7th October, 2021. The four main talks were mainly focussed on “In-farm composting. Enhancing the value of rabbit manure” by Raúl Moral (University Miguel Hernández, Spain), “Recent advances in artificial insemination” by Pilar Viudes (Instituto Valenciano de Investigaciones Agrarias, Spain), “The necessary transition of rabbit farming in Europe. The French Example” by Davi Savietto (INRAE, France), and “Social networks in rabbit farming. A practical view” by Jesús López (Grupo Editorial Agrícola-Henar Comunicación Agroalimentaria, Spain). A commercial speech on “Building immunity for a healthier world” was also presented by Sandra Gascón (Hipra). Two round tables were also held: the first on “News in veterinary prescription” with the participation of María Hernández (Spanish Ministry of Agriculture) and Mario Malo (Spanish Association of Veterinarians specialised in Rabbit Farming), and the second on “Rabbit meat processing and new products” with the participation of Raúl Grau (Universitat Politècnica de València, Spain) and María Luz de Santos (Spanish interprofessional organization to promote the rabbit sector, INTERCUN). Moreover, a total of 14 oral communications were presented by research teams from Spain, Algeria, Venezuela, Portugal and Italy. The congress was attended by around 130 participants from several European, American and African countries. Abstracts of the contributions presented are reported below.

Organic Waste Substrates Induce Important Shifts in Gut Microbiota of Black Soldier Fly (Hermetia illucens L.): Coexistence of Conserved, Variable, and Potential Pathogenic Microbes

The sustainable utilization of black soldier fly (BSF) for recycling organic waste into nutrient-rich biomass, such as high-quality protein additive, is gaining momentum, and its microbiota is thought to play important roles in these processes. Several studies have characterized the BSF gut microbiota in different substrates and locations; nonetheless, in-depth knowledge on community stability, consistency of member associations, pathogenic associations, and microbe–microbe and host–microbe interactions remains largely elusive. In this study, we characterized the bacterial and fungal communities of BSF larval gut across four untreated substrates (brewers’ spent grain, kitchen food waste, poultry manure, and rabbit manure) using 16S and ITS2 amplicon sequencing. Results demonstrated that substrate impacted larval weight gain from 30 to 100% gain differences among diets and induced an important microbial shift in the gut of BSF larvae: fungal communities were highly substrate dependent with Pichia being the only prevalent genus across 96% of the samples; bacterial communities also varied across diets; nonetheless, we observed six conserved bacterial members in 99.9% of our samples, namely, Dysgonomonas, Morganella, Enterococcus, Pseudomonas, Actinomyces, and Providencia. Among these, Enterococcus was highly correlated with other genera including Morganella and Providencia. Additionally, we showed that diets such as rabbit manure induced a dysbiosis with higher loads of the pathogenic bacteria Campylobacter. Together, this study provides the first comprehensive analysis of bacterial and fungal communities of BSF gut across untreated substrates and highlights conserved members, potential pathogens, and their interactions. This information will contribute to the establishment of safety measures for future processing of BSF larval meals and the creation of legislation to regulate their use in animal feeds.

Respon Pertumbuhan Indigofera (Indigofera zollingeriana) yang Diberikan Pupuk Kotoran Kelinci dan Biochar

Application of organic manures for improvement soil fertility is expected to increase productivity of Indigofera zollingeriana in marginal land agro-ecosystems.The aim of this study was to evaluate the growth response of Indigofera zollingeriana on application of rabbit and biochar fertilizers. This study used a completely randomized design with 3 treatments and 10 replications. The treatments consisted of T0 (chicken manure biofertilizer as control), T1 (biochar), and T2 (biochar + rabbit manure biofertilizer). The variables observed were stem height (cm), number of stalks, and number of leaves. Application of rabbit manure biofertilizer and biochar (T2) gave the highest plant height, number of stalks and leaves Indigofera of 45.68±4.18 cm, 35.80±1.03 stalk, and 128.5±11.65 leaves, respectively. Also, application T2 enhanced growth vegetative Indigofera started at 7 weeks of age (35th days after planting). It could be concluded that the combination of biochar and rabbit manure biofertilizer gives the optimal result in the growth of Indigofera.

Pemanfaatan Limbah Ternak Kelinci untuk Pembuatan Pupuk Organik Padat dan Cair

University of Islam Malang has a sister village program in Codo Village, Wajak District, Malang Regency which is recognized as a high agricultural and animal husbandry potential. In recent years, farmers in Codo village have developed rabbit farms. Further, they had a rabbit breeder group. However, the increasing number of rabbit breeders raises new problems, namely the abundance of rabbit dung. Proper strategy is needed to solve the problem. This encourages UIM to conduct a community service program on technology transfer regarding making solid and liquid organic fertilizers from rabbit dung in Codo Village. The activity focused on three tasks. First, the counseling and training for making solid and liquid compost. Second, the counseling about the importance of using organic fertilizers for soil fertility. Lastly, the discussions on various soil fertility issues related to agricultural land. This community service activity was initiated in August–November 2019 and successfully carried out with the help of students as facilitators. The use of rabbit dung as a solid and liquid organic fertilizer provided additional knowledge for rabbit breeders. They got information about the quality of rabbit manure compost and its impact on agricultural land. As a result of this activity, 83% of the community has been able to make organic fertilizer based on rabbit dung and produce solid and liquid organic fertilizer products with different chemical compositions.

Multispecies Fresh Water Algae Production for Fish Farming Using Rabbit Manure

The current study aims at determining the optimal usage conditions of rabbit manure in a multispecies fresh water algae production for fish farming. This purpose, the experimental design is made of six treatments in triplicate including one control T0, T1, T2, T3, T4, T5 corresponding respectively to 0, 300, 600, 900, 1200, 1500 g/m3 of dry rabbit manure put into buckets containing 40 L of demineralized water and then fertilized. The initial average seeding density is made of 4 × 103 ± 2.5 × 102 cells/L of Chlorophyceae, 1.5 × 103 ± 1 × 102 cells/L of Coscinodiscophyceae, 3 × 103 ± 1.2 × 102 cells/L of Conjugatophyceae, 2.8 × 103 ± 1.5 × 102 cells/L of Bascillariophyceae, and 2.5 × 103 ± 1.4 × 102 cells/L of Euglenophyceae. During the experiments, the effects of these treatments on abiotic and biotic parameters (chlorophyll-a concentration, phytoplankton density and algal density) of different production media were monitored. Results show that average density of different phytoplankton classes is higher in treatment T5 (7.91 × 108 ± 6.78 × 107 cells/L) followed by T4 (5.56 × 108 ± 4.27 × 107 cells/L), T2 (3.87 × 108 ± 3.10 × 108 cells/L), T3 (3.79 × 108 ± 3.18 × 108 cells/L, with high significant difference (F (4,84) = 5, 35, p < 0.00). Chl-a concentration varied from 0.07 ± 0.05 mg/L (T0) to 14.47 ± 12.50 mg/L (T5) with high significant differences observed among treatments (F (5,83) = 3,09, p = 0,01). In addition, fourteen (14) species belonging to eight (8) families, five (5) classes and three (3) phyla were identified in our different production media. During the culture, Chlorophyceae class was the most represented in all treatments with 5 species (36% of the specific diversity) while Euglenophyceae class (7%) was the least represented with only one (01) species. According to these results, treatments T2 (600 g/m3), T3 (900 g/m3) and T4 (1200 g/m3) of dry rabbit manure are those worthy to be recommended as an alternative for a low cost massive production of multispecies freshwater algae that can be easily used by freshwater zooplankton and macroinvertebrates. Indeed, despite the best performances that it shows, treatment T5, presents important eutrophication’s risks.

Comparative Effects of Different Organic and Inorganic Fertilisers on Soil Fertility, Plant Growth, Soil Microbial Community, and Storage Ability of Lettuce

The current study was conducted to assess whether organic fertilisation could replace mineral fertilisation in lettuce production without adverse effects on yield, quality, and postharvest behaviour. The effect of either mineral or organic fertiliser on soil fertility or the microbial community was also studied. Control plots were fertilised with recommended rates of mineral fertiliser (150: 45: 65 kg/ha NPK) and the other treatments were 15 t/ha compost, 10 t/ha rabbit manure, and 10 t/ha chicken manure. Our results indicated that all sources of organic fertiliser significantly increased total nitrogen, organic carbon, total fungi, and bacteria contents of soils compared with mineral fertiliser. Rabbit and chicken manure fertilisers resulted in a significant increase in yield. Compared with conventional fertiliser and other organic treatments, plots receiving rabbit manure showed a lower weight loss and microbial load on fresh lettuce head. Moreover, rabbit manure significantly reduced polyphenol oxidase and peroxidase activity. Hence, these results suggest that rabbit manure fertiliser could be an alternative to conventional production without significant reduction in yield and with low enzymatic browning and better storability.