Ruminal and morphometric parameters of rumen and intestine in lambs fed guava (Psidium guajava L.) agroindustrial waste

Abstract

The objective of this study was to evaluate the effect of guava agroindustrial waste (GAW) on ruminal parameters (pH, N-NH 3 , and microbial protein), volatile fatty acid (VFA), and morphometry of the rumen and intestine of sheep. A total of forty Santa Inês sheep (120 days old and 21.3±2.62 kg) were used. The animals were fed diets with 0, 7.5, 15, 22.5, and 30% inclusion of GAW. The pH, ammonia nitrogen, microbial protein, and VFA were evaluated in the ruminal fluid, alongside the morphometric characteristics of the rumen and intestine. The inclusion of GAW linearly increased fasting and postprandial pH, N-NH 3 only showed a quadratic effect for fasting animal, whereas MP presented a quadratic effect for pre-and post-prandial animals. There was a quadratic effect for papilla width, with a maximum value of 393.33 μm at the level of 34.43% GAW in the diet. The papilla absorption area showed a linear effect, in which increasing levels of GAW in the diet had a smaller area of papillae absorption. The inclusion of GAW in the diet of Santa Inês sheep favored pH neutrality, reduced N-NH 3 and ruminal MP concentrations, decreased the thickness of the rumen muscular layer, and increased the intestinal mucosa, favoring greater absorption of nutrients.

Morphological aspects of rumen papillae of lambs fed agro‐industrial wastes

“…In Brazil, the disposal of agro‐industrial waste has generated severe environmental concerns (Cavalcante, 2018). Thus, a wide variety of agro‐industrial co‐products, such as cashew peduncle (Bonfim et al, 2009), passion fruit peel (da Cruz et al, 2011), sugarcane bagasse (Caetano, 2014), and guava waste (Nobre et al, 2020), among others, have been tested for ruminant feed with promising results. The use of a wider variety of feed alternatives from regional agro‐industrial wastes should be strongly encouraged.…”

“…Intensive ruminant production systems use traditional roughage such as sorghum or corn silages, whose production is expensive and dependent on climate variations, negatively affecting feed costs. The use of agro‐industrial waste in sheep feedlots seems to be a topic of growing interest, besides contributing to environmental conservation by the better destination of these resources as dietary and nutritional inputs (Nobre et al, 2020). At the moment, wet brewery waste (Carvalho et al, 2007; Silva et al, 2010) and grape waste (Ávila et al, 2021; Massaro et al, 2022; Santos et al, 2014) are widely available in the southern region of Brazil and are considered viable dietary alternatives of good nutritional quality and low cost.…”