Developments in commercial scale farming of microalgae and seaweeds

Expanding markets for microalgae and macroalgae products have led to increased development of commercial farming operations. While microalgae and macroalgae, or seaweed, have historically been harvested in many parts of globe, more recent developments seek to improve productivity, decrease production costs, increase scale, and mitigate environmental impacts of cultivation. This chapter highlights some of those recent developments and identifies future focus areas for research and development.

Reproductive Performance of Hycole Rabbit Does, Growth of Kits and Milk Chemical Composition during Nine Consecutive Lactations under Extensive Rhythm

The goal of this study was to analyze the reproductive performance of does, growth of their kits, and chemical composition of their milk over nine consecutive parities in order to indicate the boundary of female reproductive profitability. The novelty of this study results from the combinations of three factors: extensive reproductive rhythm, commercial farming conditions, and a period of nine consecutive parities, showing the actual lifespan of a rabbit doe on commercial farms. The data was collected on 60 Hycole females kept at a commercial rabbit farm. Throughout the study, 32 does were excluded due to different reasons (e.g., excluded by means of selection—43.8% and mortalities—25.0%). The does were first inseminated at 28 weeks of age. Following artificial inseminations were conducted 14–15 days after each parturition. All kits were weaned at the age of 35 days. The following characteristics were analysed: body weight of rabbit does at artificial insemination, milk production per lactation, litter size, litter weight, average kit weight, and milk chemical composition. Rabbit does had a significant decrease in kindling rate between the eighth and the ninth parity (by 10.0 percentage points; p = 0.039). The litter size at weaning in the ninth parity was significantly lower to litters weaned at other analysed parities. The amount of milk produced per lactation was affected by the parity order (6.31–6.76 kg; p = 0.042). The litter weights on day 21 and 35 were the lowest at ninth parity. The content of total solids (TS), solids-not-fat, and fat was affected by the parity order on both analysed lactation days. The content of TS and fat in rabbit milk was characterized with a decreasing trend over the analysed period, on both lactation days. The results clearly indicate that rabbit does under extensive reproductive cycles characterize with a very good reproductive performance and can be successfully used for reproduction even up to the eighth parity. However, further research is needed if keeping them longer will not be profitable.

Metagenomic characterization of swine slurry in a North American swine farm operation

Modern day large-scale, high-density farming environments are inherently susceptible to viral outbreaks, inadvertently creating conditions that favor increased pathogen transmission and potential zoonotic spread. Metagenomic sequencing has proven to be a useful tool for characterizing the microbial burden in both people, livestock, and environmental samples. International efforts have been successful at characterizing pathogens in commercial farming environments, especially swine farms, however it is unclear whether the full extent of microbial agents have been adequately captured or is representative of farms elsewhere. To augment international efforts we performed metagenomic next-generation sequencing on nine swine slurry and three environmental samples from a United States of America (U.S.A.) farm operation, characterized the microbial composition of slurry, and identified novel viruses. We assembled a remarkable total of 1792 viral genomes, of which 554 were novel/divergent. We assembled 1637 Picobirnavirus genome segments, of which 538 are novel. In addition, we discovered 10 new viruses belonging to a novel taxon: porcine Statoviruses; which have only been previously reported in human, macaques, mouse, and cows. We assembled 3 divergent Posaviruses and 3 swine Picornaviruses. In addition to viruses described, we found other eukaryotic genera such as Entamoeba and Blastocystis, and bacterial genera such as Listeria, Treponema, Peptoclostridium and Bordetella in the slurry. Of these, two species Entamoeba histolytica and Listeria monocytogenes known to cause human disease were detected. Further, antimicrobial resistance genes such as tetracycline and MLS (macrolide, lincosamide, streptogramin) were also identified. Metagenomic surveillance in swine fecal slurry has great potential for novel and antimicrobial resistant pathogen detection.

Dairy productivity of zaanen type goats hybrids from crossing with the nubian breed bucks

Изучена молочная продуктивность потомства I, II и III поколений при скрещивании молочных коз в типе зааненской породы с козлами нубийской породы. Установлено, что самый высокий удой за лактацию (576,5±11,62) был у чистопородных зааненских коз (n=72) — на 10,8—25,3% (P≦0,05) больше, чем у помесных животных за счет более длительной лактации (на 13,0%). Среднесуточный удой за лактацию был на 2,1% выше у помесей I поколения (n=26), чем у зааненских, на 4,9% — чем у помесей II (n=24) и на 13,5% — чем у помесей III поколений (n=21) (P≦0,05). Козоматки III поколения по содержанию жира превосходили сверстниц на 0,14—0,50 абс. процента, а белка — на 0,18—0,37 абс. процента. Среднесуточное количество молочного жира было выше у помесей I поколения на 0,9—7,3%, молочного белка — на 1,5—5,1%. За счет более продолжительного периода лактации козоматки зааненской породы превосходили своих помесных сверстниц по количеству молочного жира на 5,3—11,8% (1,2—2,5 кг) и по количеству молочного белка — на 7,7—11,3% (1,2—1,7 кг). Таким образом, поглотительное скрещивание является эффективным приемом для получения чистопородных животных нубийской породы. И может быть использовано в качестве селекционного приема в товарных хозяйствах для повышения качественных показателей молока коз в типе зааненской породы. Milk productivity of the offspring of generations I, II, and III during milk goat breeding in the type of the Saanen breed with goats of the Nubian breed was studied. It was found that the highest milk yield per lactation (576.5±11.62) was demonstrated by purebred Saanen goats (n=72) — by 10.8—25.3% (P≦0.05) more than in crossbred animals due to prolonged lactation (by 13.0%). Average daily milk yield per lactation was 2.1% higher in crossbred animals of generation I (n=26) compared to the Saanen breed, 4.9% higher than in crossbred animals of generation II (n=24), and 13.5% higher than in crossbred animals of generation III (n-21) (P≦0.05). By fat content the breeding goats of generation III are superior to their age-mates by 0.14—0.50 absolute percent, and by protein — by 0.18—0.37 absolute percent. Average daily milk fat content was 0.9—7.3% higher in crossbred animals of generation I; average daily milk protein content was 1.5—5.1% higher. Due to prolonged lactation breeding goats of the Saanen breed were superior to their crossbred age-mates in milk fat quantity by 5.3—11.8% (1.2—2.5 kg), and in milk protein quantity — by 7.7—11.3% (1.2—1.7 kg). Accordingly, accumulation cross breeding is an effective method of obtaining purebred animals of the Nubian breed. It can be used as a selection technique in commercial farming to increase qualitative characteristics of goat milk in the type of the Saanen breed.

Scale Drop Disease Virus (SDDV) and Lates calcarifer Herpes Virus (LCHV) Coinfection Downregulate Immune-Relevant Pathways and Cause Splenic and Kidney Necrosis in Barramundi Under Commercial Farming Conditions

Marine farming of barramundi (Lates calcarifer) in Southeast Asia is currently severely affected by viral diseases. To better understand the biological implications and gene expression response of barramundi in commercial farming conditions during a disease outbreak, the presence of pathogens, comparative RNAseq, and histopathology targeting multiple organs of clinically “sick” and “healthy” juveniles were investigated. Coinfection of scale drop disease virus (SDDV) and L. calcarifer herpes virus (LCHV) were detected in all sampled fish, with higher SDDV viral loads in sick than in healthy fish. Histopathology showed that livers in sick fish often had moderate to severe abnormal fat accumulation (hepatic lipidosis), whereas the predominant pathology in the kidneys shows moderate to severe inflammation and glomerular necrosis. The spleen was the most severely affected organ, with sick fish presenting severe multifocal and coalescing necrosis. Principal component analysis (PC1 and PC2) explained 70.3% of the observed variance and strongly associated the above histopathological findings with SDDV loads and with the sick phenotypes, supporting a primary diagnosis of the fish being impacted by scale drop disease (SDD). Extracted RNA from kidney and spleen of the sick fish were also severely degraded likely due to severe inflammation and tissue necrosis, indicating failure of these organs in advanced stages of SDD. RNAseq of sick vs. healthy barramundi identified 2,810 and 556 differentially expressed genes (DEGs) in the liver and muscle, respectively. Eleven significantly enriched pathways (e.g., phagosome, cytokine-cytokine-receptor interaction, ECM-receptor interaction, neuroactive ligand-receptor interaction, calcium signaling, MAPK, CAMs, etc.) and gene families (e.g., tool-like receptor, TNF, lectin, complement, interleukin, chemokine, MHC, B and T cells, CD molecules, etc.) relevant to homeostasis and innate and adaptive immunity were mostly downregulated in sick fish. These DEGs and pathways, also previously identified in L. calcarifer as general immune responses to other pathogens and environmental stressors, suggest a failure of the clinically sick fish to cope and overcome the systemic inflammatory responses and tissue degeneration caused by SDD.

Simple but Complex—A Laying Hen Study as Proof of Concept of a Novel Method for Cognitive Enrichment and Research

Enrichment can reduce stress and stereotypic behavior and therefore enhance captive animal welfare. In cognitive enrichment, cognitive tasks engage and challenge the animals' natural behavioral repertoire and provide mental stimulation. Enrichment with similarities to “puzzle boxes” in cognitive research is widespread in zoos but rarely applied in commercial farming, as it requires costly time and effort. Here, we introduce a flexible method for cognitive enrichment and research. The test battery apparatus (TBA) is a configurable cubic box with frames for interchangeable test panels, each holding a problem-solving task that must be solved for a food reward. As a proof of concept, we report observations and first results from two groups of laying hens (Gallus gallus forma domestica; 52 birds in total) to show the TBA's feasibility in commercial farming and to investigate the animals' spontaneous interaction with four test panels. While we could not reliably identify individuals, we found the majority of the hens highly motivated to engage with the device. At least five individuals in each group were successful and there was a significant gradient of success rates across the four panels. As the implementation and maintenance required little time and effort, the TBA is promising as a cognitive enrichment device in farm settings. Its potentially limitless configurations allow diverse opportunities for cognitive and behavioral engagement in the long term. While further studies will be crucial to validate welfare effects and problem-solving tasks, the TBA is simple in its application but complex in its possibilities.

Recognizing Determinants to Smallholders’ Market Orientation and Marketing Arrangements: Building on a Case of Dairy Farming in Rural Kenya

Smallholder commercialization is central to international development policy and practice. As a result, several arrangements to foster market linkages are being implemented. Especially popular are farmers’ organizations, which are believed to be owned, controlled, and financed by smallholders. As such, their design is considered inclusive given every household in a community is theoretically allowed to become a member, and the governance and management structure encourage participatory decision-making. However, even in the context in which farmers’ organizations are actively promoted, a notable proportion of smallholders may not be able to engage in market-oriented production or may opt for the existing alternative marketing arrangements, as dictated by individual households’ socioeconomic characteristics. Focusing on the case of smallholder farming in Olenguruone, Nakuru county, Kenya, where a donor funded dairy farmers’ cooperative marketing arrangement is promoted alongside existing marketing opportunities, the present research investigated the factors that determine smallholders’ commercial farming orientation and marketing arrangements. It employed a case study approach, combining both quantitative and qualitative research methods for a more complete empirical inquiry. The findings demonstrate that irrespective of the external support provided through marketing opportunities such as farmer organizations, smallholders’ engagement in commercial farming and marketing is dictated by the socioeconomic attributes and market perceptions that are heterogeneous among households in a smallholder community.