Neltuma spp. are an important resource in arid and semiarid ecosystems of the country and serve, among other purposes, as an economic source of food for livestock. By analyzing the bromatological composition and in vitro fermentation of pods in three regions of the state of Zacatecas, Mexico, the viability as a food alternative in sheep is sought. Twenty-seven pod samples were collected from nine points in each region of the state. The samples were obtained when the pods were in the immature stage. The bromatological analysis of the pods was conducted and mathematical equations were used to calculate the megacalories per kilogram provided by these fruits. Statistical analysis was performed using Spearman’s correlation coefficient. Bromatological analysis showed that crude protein averaged 20.86 ± 1.37% in the central region, while non-fiber carbohydrates averaged 26.78 ± 1.32% in the southern region. Neltuma spp. pods demonstrate potential as an alternative feed for sheep, provided that an adequate diet is formulated, since they present acceptable levels of protein, carbohydrates and fiber. It is recommended to consider the state of maturity of the pods when incorporating them into the diet of sheep.

During the dry season in semi-arid regions, pastures become scarce and low in nutritional quality. These conditions compromise the digestive physiology and ruminal health of sheep. Consequently, consuming forages high in fibre and deficient in nitrogen leads to reduced digestive efficiency. Evaluating unconventional local resources, such as the pods of Neltuma spp., is essential for determining their ability to optimise fermentation kinetics without disrupting the ruminal ecosystem. The objective of this study was to evaluate the effects of replacing commercial feed with increasing levels of Neltuma spp. pods (20%, 40%, and 60%) collected from three geographic regions of Zacatecas, Mexico, on in vitro ruminal fermentation kinetics, microbial activity parameters, and digestive health indicators, measured in sheep ruminal fluid. Samples of Neltuma spp. pods were collected from three regions of the state of Zacatecas, and mixtures were prepared using commercial feed and ground Neltuma spp. pods in ratios of 80:20, 60:40, and 40:60, which were subjected to bromatological analysis; a ruminal fluid inoculum obtained from Dorper sheep adapted to a diet based on commercial feed was used for in vitro fermentation. Gas pressure, ammoniacal nitrogen concentration, and pH were monitored every 6 h during a 48 h incubation period. Principal component analysis, analysis of variance, and Tukey’s tests for comparing means were conducted to evaluate the effects of inclusion level and region of origin. The first two principal components explained 99.08% of the total variability, demonstrating a correlation between the content of fibrous fractions and the proportion of non-fibrous carbohydrates. In vitro ruminal fermentation showed an upward trend across all treatments over time; mixtures with a moderate pod inclusion level of 20% achieved the highest gas production volumes. Ammoniacal nitrogen profiles showed a progressive increase across all treatments. The fermentation pH decreased gradually as the carbohydrate degradation process progressed. It is concluded that the inclusion of 20% and 40% Neltuma spp. pods, particularly those from the central region, represents a viable nutritional strategy for improving energy and protein intake in sheep during the dry season.

The Mexican duck (Anas diazi) is an endemic species that has been categorized as threatened because of its practice of living in small populations and because of the condition of the wetlands in which it occurs. Therefore, the preference for wetlands by the species is influenced by the adjacent vegetation composition found in the Mexican Central Plateau in the state of Zacatecas. The inclination of the duck towards the wetlands in relation to the aquatic and adjacent vegetation structure was evaluated in the studied area. Seven wetlands were selected and distinguished by the presence of a population of the species. Vegetation was analyzed in three strata—tree layer, shrub layer and herb layer—and the population of the Mexican duck was calculated through direct counting in each wetland. The results determined a significantly larger number of individuals in artificial wetlands than in lakes. The wetlands’ adjacent vegetation is constituted by graminean and shrub species, with an aquatic vegetation cover. The non-parametric Mann–Whitney U test showed a significant difference between the counts of ducks and the physical structure of wetlands in the examined area. The data obtained indicate that the Mexican Duck occurs mainly in artificial wetlands with mainly graminean vegetation and aquatic plant cover; similar characteristics to those previously described for dabbling ducks.