This study evaluated the effects of chemical and biological preservatives and ensiling stage on spoilage, ruminal in vitro fermentation, and methane production of wet brewer’s grain (WBG) silage. Treatments (TRT) were sodium lignosulfonate at 10 g/kg fresh WBG (NaL1) and 20 g/kg (NaL2), propionic acid at 5 g/kg fresh WBG (PRP, 99%), a combination inoculant (INO; Lactococcus lactis and Lactobacillus buchneri each at 4.9 log cfu/fresh WBG g), and untreated WBG (CON). Fresh WBG was treated and then ensiled for 60 d, after which mini silos were opened and aerobically exposed (AES) for 10 d. Data were analyzed as a RCBD (5 blocks) with a 5 TRT × 3 stages (STG; Fresh, Ensiled, and AES) factorial arrangement. Results showed that Ensiled PRP-treated WBG markedly preserved more water-soluble carbohydrates and starch than all other Ensiled TRT (P<0.001). Dry matter losses of Ensiled PRP-treated WBG were 48% lower than all other Ensiled TRT (P=0.009) but were not different than CON in AES (P=0.350). Due to its greater concentration of digestible nutrients, PRP-treated AES was less aerobically stable than CON (P=0.03). Preservation was not improved by INO, NaL1 or NaL2 but the latter prevented the increase of neutral detergent fiber across STG (P=0.392). Apparent in vitro DM digestibility (IVDMD) decreased only in Ensiled CON, INO and NaL1 relative to Fresh WBG and AES NaL2 had greater IVDMD than all other AES TRT (P≤0.032). In vitro ruminal fermentation of Fresh WBG resulted in a greater methane concentration and yield than the other STG (P<0.033). In conclusion, PRP was the most effective at preserving WBG during ensiling but failed to improve aerobic stability under the conditions tested.

Our objectives were to compare the antifungal activity of 5 lignosulfonates, and 2 chitosans against fungi isolated from spoiled hay, and assess the effects of an optimized lignosulfonate, chitosan, and propionic acid (PRP) on high-moisture alfalfa hay. In experiment 1, we determined the minimum inhibitory concentration and minimum fungicidal concentration of 4 sodium lignosulfonates, 1 magnesium lignosulfonate, 2 chitosans, and PRP (positive control) against Aspergillus amoenus, Mucor circinelloides, Penicillium solitum, and Debaromyces hansenii at pH 4 and 6. Among sodium lignosulfonates, the one from Sappi Ltd. (NaSP) was the most antifungal at pH 4. However, chitosans had the strongest fungicidal activity with the exception of M. circinelloides at both pH 4 and 6. PRP had more antifungal effects than NaSP and was only better than chitosans for M. circinelloides. In experiment 2, we evaluated the effects of 3 additives (ADV): optimized NaSP (NaSP-O, UMaine), naïve chitosan (ChNv, Sigma-Aldrich), and PRP on high-moisture alfalfa hay. The experimental design was a randomized complete block design replicated 5 times. Treatment design was the factorial combination of 3 ADV× 5 doses (0, 0.25, 0.5, 1, and 2% w/w fresh basis). Additives were added to 35 g of sterile alfalfa hay (71.5 ± 0.23% DM), inoculated with a mixture of previously isolated spoilage fungi (5.8 log cfu/fresh g), and aerobically incubated in vitro for 23 d (25°C). After incubation, DM losses were reduced by doses as low as 0.25% for both NaSP-O and PRP (x=1.61) vs. untreated hay (24.0%), partially due to the decrease of mold and yeast counts as their doses increased. Also, hay NH₃-N was lower in NaSP-O and PRP, with doses as low as 0.25%, relative to untreated hay (x= 1.13 vs 7.80% of N, respectively). Both NaSP-O and PRP increased digestible DM recovery (x= 69.7) and total volatile fatty acids (x= 94.3), with doses as low as 0.25%, compared with untreated hay (52.7% and 83.8 mM, respectively). However, ChNv did not decrease mold nor yeast counts (x= 6.59 and x= 6.16 log cfu/fresh g; respectively) and did not prevent DM losses relative to untreated hay. Overall, when using an alfalfa hay substrate in vitro, NaSP-O was able to prevent fungal spoilage to a similar extent to PRP. Thus, further studies are warranted to develop NaSP-O as a hay preservative under field conditions.

The objective of this study was to evaluate four different feeding strategies using an immunomodulatory feed additive for newly weaned Nellore cattle, before and after road transport, on their physiological parameters and performances during the growing phase of pastures. In total, eighty-four young Nellore bulls (initial BW = 174 ± 11 kg; 7 ± 1 months of age) were blocked by their initial body weights 42 days before road transport (d −42) and randomly assigned to one of the four supplementation strategies. The treatments were: (1) Control (CON): no immunomodulatory feed additive (NUTRA) supplementation; (2) NUTRA pre: the inclusion of NUTRA only in the pre-transport period (d −42 to d 0); (3) NUTRA post: the inclusion of NUTRA for 42 days, only in the post-transport period (d 0 to d 42); and (4) NUTRA growth: the inclusion of NUTRA during the whole experimental period (d −42 to d 210). On d 0, the calves were transported on dirty roads in a commercial livestock trailer for 200 km (8 h). There was no effect of the treatments on the animal performance or the physiological parameters in their plasma. However, there were effects on the day of the blood sampling for all the parameters. The highest concentration of cortisol was observed on d 3 post-transport (129 ng/mL) and this decreased over time (22.4 ng/mL; d 210). On the other hand, their glucose peaked at unloading, with lower concentrations on d 7 and d 14. Their total protein concentrations increased from d 0 to d 7. The immunomodulatory feed additive supplementation at 10 g/100 kg BW/day did not modulate the physiological responses in their plasma and did not influence the performance of the Nellore bulls during the growing phase of their pastures.

Despite the critical importance of nutritional assessment in veterinary medicine, internationally recognized guidelines for compromised ruminants remain absent. This paper addresses this significant gap by presenting comprehensive nutritional assessment protocols adapted from small animal and equine guidelines, combined with clinical experience and ruminant-specific considerations. Therefore, the objective of this article is to establish standardized nutritional assessment guidelines for compromised ruminants that facilitate early detection of risk factors and nutritional imbalances affecting animal welfare and productivity, while guiding appropriate clinical nutritional interventions. The guidelines integrate systematic screening and extended evaluation protocols encompassing patient signalment, comprehensive health interviews, environmental examination, and nutrition-focused clinical assessments. The framework incorporates validated scoring systems including body condition scoring, fecal consistency and digestibility scores, rumen fill assessment, and muscle scoring. Laboratory evaluations including blood biochemistry, hematology, milk quality records, and metabolite profiling support clinical decision-making. The proposed assessment framework addresses animal-specific factors, diet-related considerations, feeding management practices, and environmental influences on nutritional status. Critical evaluation points include alimentary system function and integrity, forestomach assessment, and detection of malabsorption syndromes. The guidelines emphasize that many nutritional abnormalities manifest non-specifically, and detection limitations exist, particularly in peracute presentations. In conclusion, successful clinical nutritional interventions require comprehensive assessment protocols that prioritize rumen health maintenance and oral diet delivery whenever possible. The guidelines we suggest will provide veterinary and nutritional practitioners with systematic tools for evaluating compromised ruminants, establishing appropriate interventions, and monitoring outcomes using SMART goals. Further research is warranted to refine specific dietary requirements for compromised ruminants and validate intervention protocols across diverse production systems.

A significant gap in specific nutritional guidelines for ruminants with compromised health exists. Due to their unique anatomy, physiology, and metabolic processes, further research is needed to establish accurate, evidence-based recommendations tailored to these animals. This review highlights the critical role of clinical ruminant nutrition and provides provisional recommendations based on studies in other species (e.g., changes in nutrient requirements in different morbidities available for humans and less for companion animals). These suggestions should be interpreted cautiously until more definitive, species-specific data become available. The review includes the foundational principles of clinical nutrition in ruminants, with particular emphasis on the pathophysiology of nutrient utilization. It explores the roles of energy, protein, vitamins, and minerals during illness or injury and discusses how these nutrients can be strategically applied in clinical interventions. Considerations for designing diets for compromised ruminants are also addressed, considering both physiological needs and the challenges posed by illness and injury states. Practical aspects of diet delivery during treatment are examined, including the indications, benefits, limitations, and potential side effects of route of feeding. Clinical nutrition can be administered orally, enterally (including rumen delivery) or parenteral, depending on the localization of the pathology and the integrity of the alimentary tract. Nutrients should be provided based on livestock requirements and pathophysiology and severity of the primary morbidity. Oral or ruminal provision of diet should be prioritized to maintain rumen functionality. Additionally, a list of pharmaconutrients with potential clinical applications in ruminant medicine is presented to encourage future research and integration into veterinary practice. The success of clinical nutritional interventions can be measured by improvements in appetite, behavior, and health of the compromised ruminant.