Animal diseases-पशुओ की बीमारिया

Obstructive Urolithiasis in Ruminants: Economic loss to farmers

Team Pashudhan Praharee

May 30, 2023

607

Obstructive Urolithiasis in Ruminants: Economic loss to farmers

Amit Kumar*, Naveen Kumar, and Sandeep Saharan

Department of Veterinary Surgery and Radiology

Department of Veterinary Public Health and Epidemiology

Department of Animal Genetics and Breeding

Lala Lajpat Rai University of Veterinary and Animal Science, Hisar (Haryana), India-125004

Corresponding author: Amit Kumar, amitdhartterwal@gmail.com

ABSTRACT

Obstructive urolithiasis is a significant health issue in young calves and poses a serious threat to the lives of livestock animals. It carries significant economic implications for farmers due to the high mortality rate associated with bladder rupture and the expenses involved in treatment. It is crucial to educate livestock owners about the importance of water consumption in animals at risk of developing urolithiasis. One effective strategy is to include salts in their diet, which promotes increased water intake and the production of large volumes of diluted urine.

Keywords: Urolithiasis, Ruminants, Farmers

Introduction

Obstructive urolithiasis is a commonly encountered surgical condition in various animal species, with cattle, buffalo, and sheep being the most affected. It poses a significant threat to ruminants and can lead to substantial economic losses. Urolithiasis is characterized by the formation of uroliths, which are less soluble crystalloids, resulting from congenital and/or acquired pathophysiological processes that increase their concentration in urine (Osborne and Kruger, 1984). Urethral obstruction, urinary bladder rupture, and subsequent uremia are potential complications of urolithiasis. While both male and female animals can be affected, males are more susceptible due to their long and narrow urethra (Makhdoomi and Gazi, 2013). Urethral obstruction caused by uroliths or calculi leads to urine retention in the bladder and subsequent overdistention. Without early treatment, the urinary bladder or urethra may rupture, significantly worsening the animal’s condition. Ruminants are more prone to phosphate calculi due to an imbalance in the calcium-to-phosphorus ratio and a high phosphorus diet (Radostits et al., 2000). Struvite uroliths are the primary component of urinary calculi in water buffaloes fed high levels of cottonseed meal (Wang et al., 1997). The formation of struvite uroliths requires the urine to be supersaturated with magnesium ammonium phosphate crystals. Several factors contribute to the formation of phosphate calculi, including heavy concentrate-low roughage diets, limited water intake, dehydration, urine alkalinity, mineralized artesian water, excessive sodium bicarbonate in the diet, vitamin imbalances (hypovitaminosis or hypervitaminosis), and high protein rations (Samal et al., 2011).

Etiopathogenesis:

Young castrated males are more susceptible to urolithiasis, a condition characterized by the formation of urinary calculi. Castration leads to a narrowing of the urethral diameter, making these animals more prone to the obstruction caused by calculi (Larson, 1996). Testosterone hormone plays a vital role in the normal development of the urethra and the secretion of protective colloids in male animals’ urine (Williams, 1955). Urethral obstruction primarily occurs when calculi become lodged in the urethral passage. Several factors contribute to the etiology of urolithiasis to varying degrees, including sex, age, breed, season, hormonal imbalance, feed composition, mineral content, infection, skin texture, genetic makeup, soil, location, vitamins, and water intake (Sharma and Singh, 2001; Avioli, 1978; Wang et al., 1997; Bailey, 1978). In bovines, uroliths can lodge anywhere in the urinary tract, from specific locations in the kidney to the glans penis. However, the most common sites of obstruction are the distal part of the sigmoid flexure and the glans penis (Gera and Nigam, 1979; Sharma and Singh, 2001). The chemical composition of urinary calculi varies depending on the dietary composition of individual elements, geographical location, and local management practices (Singh and Singh, 1990). Kopper (1967) observed a high incidence of urolithiasis during winter months, which was attributed to reduced water consumption and a deficiency of vitamin A. During winter, frequent feeding of concentrates leads to the release of antidiuretic hormone, resulting in decreased urine output and increased urine concentration temporarily (Hofmeyr, 1987). Hopper (1998) suggested that the increased urine concentration and pH contribute to enhanced mineral excretion in the urine, reducing the concentration of protective colloids and promoting urolith formation.

Clinical Signs:

Clinical signs in animals with intact urinary bladder are anuria, inappetence to anorexia, reluctance to walk, respiratory distress, prolonged recumbency, normal alert to depressed and dull appearance, sunken eyes, dry to moist muzzle, engorged urethra, twitching of penis, straining for urination, maintaining urinary posture for prolonged periods, tail lifting, frequent attempt to urinate, prolapse of rectum and pain on palpation of penis/urethra (Kushwaha et al., 2014). Classical clinical sign of urinary bladder rupture is a pear-shaped abdomen (Braun and Nuss, 2015).

Treatment:

Medical treatment has been moderately successful in relieving obstruction during the early stages of obstructive urolithiasis. However, once the urethral obstruction becomes complete, surgical intervention becomes necessary. Surgical therapies for the management of obstructive urolithiasis aim to either remove the uroliths to restore normal urine flow or divert the urinary tract to allow time for the restoration of patency. One such surgical intervention is tube cystostomy, which is performed in bovine calves to treat obstructive urolithiasis. This procedure involves the placement of a Foley’s catheter into the urinary bladder lumen via a laparotomy, providing urinary diversion or urethral bypass (Van Metre, 2004). In addition to surgical intervention, the main goal of medical treatment is to prevent further urolith growth and promote urolith dissolution. This can be achieved by inducing undersaturation of urine with calculogenic crystalloids or by increasing the solubility of crystalloids and the volume of urine in which they dissolve. Altering the pH of urine or promoting diuresis are common approaches to achieve these objectives (Osborne et al., 1990). Ammonium chloride is a commonly used urinary acidifier with anti-struvite activity. It is an inexpensive, widely available option that has been studied for its prophylactic effects in preventing uroliths (Senthilkumar et al., 2001).

Conclusion

Obstructive urolithiasis is a complex disease that can affect various domestic animal species and poses a significant risk to ruminants. This condition is life-threatening and requires prompt veterinary intervention to prevent potential economic losses. Ruminants are particularly susceptible to urolithiasis during the peak winter and summer months. It is therefore essential to educate livestock owners about the importance of water consumption in animals at risk of developing urolithiasis. One effective strategy to encourage increased water intake is by supplementing the animal’s diet with salts, which promotes the consumption of larger volumes of water and facilitates the production of diluted urine, reducing the risk of urolith formation.

References

Avioli, L.V. (1978). Pathogenesis and significance of hormonal metabolic derangements in uremia. Am. J. Clin. Nut., 31: 1554-1560.

Bailey, C.B. (1978). Comparison of kidney and bladder calculi from cattle on a diet known to cause formation of siliceous urinary calculi. Can. J. Anim. Sci., 58: 513-515.

Braun, U and Nuss, K. (2015). Uroperitoneum in cattle: Ultrasonographic findings, diagnosis and treatment. Acta Veterinaria Scandinavica., 57: 1-9.

Gera, K.L. and Nigam, J.M. (1979). Urolithiasis in Bovines: A report of 193 clinical cases. Indian Vet. J., 56(5): 417-423.

Hofmeyr, C.F.B. (1987). Ruminant Urogenital Surgery. Iowa State University Press pp 15-28.

Hooper, N.R. (1998). Management of urinary obstruction in small ruminants. Proceeding, Western Veterinary Conference pp 99-106.

Kopper, S.A. (1967). Relation between successful treatment of cases of retention of urine in bullocks and the position of the calculi. Gujarat Veterinarian 1: 58.

Kushwaha, R.B, Amarpal, A.H, Kinjavdekar, P. and Pawde. A.M. (2014). Clinical appraisal of 48 cases of obstructive urolithiasis in buffalo calves treated with tube cystostomy and urethrotomy. Adv. Anim. Vet. Sci., 2(2): 106-10.