Sawdust-induced rumen impaction with concurrent rumen tympany in a Balami ram

Rumen foreign body impaction and tympany are significant gastrointestinal disorders in ruminants worldwide, often linked to the ingestion of indigestible materials such as polythene bags, plastic, clothing items, mosquito nets, ropes, metal, hair, hide, nails, wood strips, and low-quality or indigestible feed materials, which accumulate in the rumen and disrupt normal digestive processes. These conditions can severely impact animal health, productivity, and farm profitability, particularly in regions where high-fiber, low-digestibility forages are prevalent [1-7]. Feeds with high fiber content and low digestibility can increase the risk of impaction due to slow rumenal passage and reduced microbial degradation [8, 9]. This risk can be further compounded by poor feeding management, abrupt dietary changes, and inadequate adaptation periods, which may destabilize rumen microflora [3, 10]. Rumen tympany (bloat) can be classified into two types: primary (frothy) and secondary (free-gas) bloat. Primary bloat is often caused by the rapid fermentation of high-protein forages or finely ground grains, resulting in a stable foam that traps gas. In contrast, secondary bloat occurs due to physical or functional blockages that prevent eructation of gas and can be worsened by rumen atony associated with low-quality diets [11, 12]. Rumen impaction and tympany in ruminants can be managed through surgical or non-surgical strategies, with the choice of treatment depending on the severity and underlying cause. Rumenotomy is often the most effective approach for severe cases caused by indigestible foreign bodies, with high success rates when performed promptly [13-16]. Non-surgical strategies, such as fluid and antibiotic therapy, purgatives, supportive care, and dietary adjustments, may be effective for mild to moderate cases of impaction and tympany, especially when caused by fibrous, low-digestibility feed rather than foreign bodies [6, 17, 18]. Notably, despite documentation of various indigestible foreign materials implicated in rumen foreign bodies, sawdust has not been previously reported as a rumen-impacting foreign body, to our knowledge. This article reports the first case of sawdust-induced rumen impaction with concurrent rumen tympany and highlights the importance of considering unusual causes of rumen impaction and tympany in small ruminants. This study describes the clinical presentation, diagnosis, and successful surgical management of rumen impaction with concurrent rumen tympany in a Balami ram resulting from sawdust ingestion.

2. Materials and methods

2.1. Case history

A 3-year-old Balami ram weighing 37 kg was presented to the Large Animal Clinic Unit of the Veterinary Teaching Hospital, University of Jos (VTHUJ), Nigeria, with a history of inappetence, rapid respiration and bilaterally distended abdomen (Figure 1A). According to the owner, he had lost three rams two days prior, after manifesting similar clinical signs of rapid respiration and abdominal distention, following ingestion of sawdust used to insulate the cold floor where the rams were housed under an intensive management system.

2.2. Clinical and laboratory examinations

Upon presentation of the ram to the clinic, a thorough clinical examination was conducted and all the clinical findings were recorded. The ram’s vital parameters, including respiratory rate, rectal temperature, and pulse rate, were evaluated and also recorded. After a comprehensive clinical examination, a 5 mL whole-blood sample was obtained from the jugular vein into an ethylenediaminetetraacetic acid (EDTA) tube and sent for hematological analysis. Abdominal ultrasonography was recommended to facilitate the diagnosis. The abdominal flanks of the ram were shaved and prepared, after which the ultrasonography was performed using a 3.5 MHz convex probe and a DAWAI MU10 Ultrasound Scanner. Based on the impacted ram’s history, its critical state on presentation, the clinical findings and the ultrasonography findings (Figure 1B), a definitive diagnosis of sawdust-induced rumen impaction with concurrent rumen tympany was made, necessitating emergency rumenotomy to relieve the ram’s condition.

2.3. Anaesthesia, surgical management and post-operative care

The surgical site (shaved left flank region) of the impacted ram was scrubbed and disinfected with povidone iodine (Kattle Care Ltd, Nigeria). The ram was then physically restrained in right lateral position on the surgical table, and a laparotomy drape was applied over the proposed surgical site. Local anesthesia was achieved by infiltrating 1% Lidocaine (Pharma X India Pvt. Ltd., Mumbai, India) at 2 mg/kg via an inverted L pattern to desensitize the region and abolish pain during the surgical procedure. A 5cm vertical skin incision was made into the subcutaneous tissue at the left flank region (Figure 2A), and the abdominal muscles were separated along the direction of their fibers. A stab incision was made into the peritoneum and carefully extended along the incision line to approximately 7 cm, sufficient to allow exteriorization of the rumen. The peritoneum was explored, and part of the bloated rumen was carefully exteriorized (Figure 2B). A stab incision was made on a relatively less vascularized area of the dorsal ruminal wall to decompress the distended rumen. The incision was then extended to approximately 5 cm to access the ruminal contents (Figure 2C), allowing careful evacuation of the impacted material (sawdust) from the rumen. The ruminal incision was closed in two layers using Cushing suture pattern (Figure 2D), using size 1 chromic catgut (Huaian Angel Med. Inc. Co., Ltd., Jiangsu, China), after which the rumen was returned to the peritoneal cavity. The peritoneum and abdominal muscles were apposed together with size 2 Polyglactin 910 suture (Agarycryl, Angel Med. Ins. Co., Ltd, China) in a continuous suture pattern, followed by subcutaneous tissue closure using a subcuticular suture pattern. Routine skin closure with size 2 silk suture (Kangning Ind., Co., Ltd, Tianchang, China) was then performed in an interlocking pattern [19]. Postoperative care was composed of alternate-day wound dressing. Postoperative medications included intramuscular administration of 20% Amoxicillin (five-Amox.20@ LA, Central Vet. Med. No. 5, Hanoi-Vietnam) at 20mg/kg, repeated after 48 hours, and 2.5% Diclofenac (Jiangxi Kangtai Pharmaceutical Co., China) at 1.5 mg/kg for three consecutive days [20].

3. Results

3.1. Clinical findings and laboratory results

Upon thorough clinical examination, the ram exhibited bilaterally bloated abdomen (Figure 1A) with tympanic sound on percussion, a ventrally distended and doughy abdomen on palpation, reduced rumen motility, polypnea, and bruxism (teeth grinding), indicative of abdominal pain. The ram’s rectal temperature and pulse rate were 38.2°C and 140 beats/min, respectively.

Comprehensive hematological analysis revealed that the hematological parameters were within the reference ranges reported in Schalm’s Veterinary Haematology (Table 1) [21], except for moderate leukocytosis attributed to moderate eosinophilia. The abdominal ultrasonographic findings revealed hypoechoic and hyperechoic areas (Figure 1B), indicative of indigestible material (foreign body) and gas buildup in the rumen. These findings, combined with the clinical findings and the impacted ram's history, facilitated a definitive diagnosis of rumen impaction with concurrent rumen tympany, prompting an emergency rumenotomy to relieve the tympany and evacuate the indigestible material causing the impaction.