Maria Ndakula Tautiko Shipandeni

Climate change is a pressing global challenge, and animal production is a major contributor to methane emissions. This study examines the academic landscape of research on CH₄ emissions and animal productivity, with a focus on cattle, sheep, and goats. Using a bibliometric analysis of 2500 documents published between 1987 and 2023, the study finds that research on this topic has increased significantly over time, with a record high in 2022. The leading countries in terms of research output are the United States, China, Brazil, Canada, and Italy. The study identifies several key research themes, including the impact of CH₄ emissions on animal productivity parameters, the development of mitigation strategies, and the assessment of trade-offs and synergies between CH₄ emissions reduction and other sustainability goals. The study concludes by highlighting the importance of continued research on CH₄ emissions and animal productivity to develop and implement effective mitigation strategies. This study has important implications for policymakers, researchers, and the livestock industry. Policymakers can use the findings to inform the development of policies and regulations that support the reduction of CH₄ emissions from animal production. Researchers can use the findings to identify gaps in the existing knowledge base and to develop new research directions. The livestock industry can use the findings to develop more sustainable production practices. By working together, policymakers, researchers, and the livestock industry can develop and implement effective mitigation strategies that reduce greenhouse gas emissions, protect the environment, and support sustainable food production.

The global outbreak of the unprecedented COVID‐19 pandemic has posed numerous challenges in the agro‐food systems worldwide urging the need to build resilient food systems for food security. Urban agriculture (UA) has the potential to contribute to resilient and sustainable food systems. This study investigated the impact of COVID‐19 on UA practices in the informal settlement of Windhoek, Namibia. Samora Machel and Tobias Hainyeko constituencies were purposively selected using a stratified two‐stage probability sampling design within each constituency to select the study sites and a sample of 59 households were interviewed using a structured questionnaire with open‐ and closed‐ended questions. Descriptive statistical analyses were performed to identify constraints and coping strategies employed by urban farmers in informal settlements. Households that participated in the study were engaged in UA with 60.4% male‐headed households. Horticultural crop production (67.2%) and mixed farming (18.2%) were the main activities. The major constraints were high input costs (74.6%), inadequate land (61%), and unavailability of water (59%). The major coping strategies were intensified/started production (43%), use of alternative locally available inputs and resources (22%), changed marketing strategy (11%), and reduced hired labor (8%). The community resilience was weakened during the COVID‐19 pandemic. A holistic and integrated approach to urban planning and policy that recognize UA within the broader food system is required. There is a need to strengthen policy on land use and infrastructure planning that incorporates both formal and informal food systems and enhances disaster risk preparedness.

Developing efficient feeds and sustainable feeding systems is required to meet the increasing demand for livestock and livestock products

Cereal grains are the predominant starch source (SS) for dairy cows; however, starch digestibility varies greatly depending on source, grain processing, and potentially interactions between these factors. The objective was to study the effects of the interactions between SS, and particle sizes (PS) on ruminal fermentation, nutrient flow, starch digestibility, and lactation performance of dairy cows. Four ruminally cannulated multiparous Holstein cows were used in a 4 × 4 Latin square design with a 2 × 2 factorial arrangement of treatments. Two SS (corn or sorghum) used in this study were either finely or coarsely ground (using a 1- or 4-mm screen sieve). Digesta flow was quantified using the reticular sampling technique, applying the triple-marker method. Data were analyzed using the GLIMMIX procedure of SAS version 9.3 (SAS Institute Inc., Cary, NC, USA). For ruminal pH, data were analysed with time as repeated measure. There were no interactions between SS and PS on production or intake, flow, and digestibility of nutrients. Dry matter intake was greater for the corn diet compared to the sorghum diet (25.15 vs. 21.98 kg/d), which consequently affected nutrient intake, however, PS did not affect intake. Milk yield was not affected by SS; however, it was greater for cows fed fine grains than cows fed coarser grains (25.32 vs. 23.16 kg/d). Milk fat and milk protein were not affected by SS or PS. Interactions (SS × PS) were observed for ruminal pH, reticular pH, and volatile fatty acids (VFA) concentrations but not for ruminal NH₃–N concentration. Ruminal and reticular pH were greater for sorghum when coarsely ground and the total VFA concentration was decreased, compared to coarse corn and fine sorghum; however, coarsely grinding corn did not affect ruminal or reticular pH nor VFA concentration. Acetate concentration was lower for corn when finely ground; however, finely grinding sorghum did not affect acetate. Decreasing PS increased ruminal digestibility of starch (87.18% vs. 83.43%), reduced the flow of starch to the reticulum (0.79 vs. 0.96 kg/d) but decreased neutral detergent fiber digestibility in the rumen (30.23% vs. 34.88%). Although SS were differently affected by processing, the effects of PS on production, intake, flow, and digestibility of nutrients were observed regardless of the SS. Furthermore, the effects of decreasing PS on pH and VFA concentrations were more pronounced in sorghum compared to corn. Starch digestibility varies greatly depending on starch source (SS), grain processing, and potentially interactions between these factors. Four ruminally cannulated lactating Holstein cows were fed a total mixed ration that varied in SS and particle sizes (PS) to evaluate the interactions between SS and PS on ruminal fermentation, nutrient flow, starch digestibility, and lactation performance of dairy cows. There were no interactions between SS, and PS on production, intake, flow, and digestibility of nutrients; however, interactions were observed for ruminal pH, reticular pH, volatile fatty acids (VFA) concentrations, and in some VFA molar proportions.

The objective of this study was to determine the relative palatability of four native forage legumes (Otoptera burchellii, Crotalaria argyraea, Crotalaria podocarpa and Vigna lobatifolia) in comparison with each other and with Lucerne (Medicago sativa). Eight weaned Boer goats aged 6 months and weighing 25.2 ± 4.9 kg were grouped by sex, and then randomly allocated to individual pens. Goats were simultaneously offered 100 g of each of the four native legumes and 600 g of M. sativa (as-is basis) over a 10-day period. Grass hay (Cenchrus ciliaris), fresh water and mineralised salt licks were available at all times. Grass hay was given to allow diet mixing and possibly ameliorate any undesirable effects, such as bloat, due to feeding on legumes alone. The percentage of each species consumed of that offered was associated (P < 0.001) with legume species, day and legume × day interaction. Over 95% of the O. burchellii, V. lobatifolia and Lucerne offered were consumed from Days 1 to 10. The amounts of Crotalaria spp. consumed fluctuated widely in the first 4 days, but increased thereafter to >95% of that offered. This study demonstrated that hay of all the four native forage legume hays were palatable to Boer goats, with the inferred ranking being: (Lucerne, V. lobatifolia) > O. burchellii > Crotalaria spp. Further studies are required to investigate the productivity of goats feeding on these native forage legumes, which have potential for use in marginal lands.