There is a diversified microbial ecosystem in the rumen for efficient utilization of diet by providing essential nutrient to their host. But there are different factors affecting rumen microbial protein synthesis which are physical factors, chemical factors, dietary factors, biological factors and endogenous factors. Among the details of factors, dietary factors and ruminal pH are the dominant factors influencing rumen microbial protein production. The effects of some dietary factors, on the amount and efficiency of microbial protein synthesis, are discussed in this review. Specifically, these factors include forage quality diets, level of feed and types of feed. It seemed that diets containing a mixture of forages and concentrates increase the efficiency of microbial protein synthesis because of an improved rumen environment for the growth of more diverse bacterial species. This review describes physical and chemical factors which include: pH and buffer system, oxygen concentration, rumen outflow rate and synchronized release of nitrogen and energy from the diet, a nitrogen compound, energy spilling, vitamins and minerals and antimicrobials chemicals, respectively. Age, species, physiological status, sex, and stress are among endogenous factors that mostly affect microbial protein synthesis of a ruminant. Bacteriophages, protozoa predation and bacterial lysis are biological factors affecting the efficiency of microbial protein synthesis. All these factors have a direct effect on the synthesis of microbial protein in the rumen. Therefore, the cumulative effects of the above factors are resulted in the depopulation of rumen microflora and finally reduction of animal product. So, improvement in quantitative aspect of microbial protein synthesis solves many problems from simple to complex so that, the quantitative aspect of rumen microbial biomass are invaluable for health and productivity of ruminants than qualitative aspect hence, maintain health rumen ecosystem means having healthy ruminant.

Keywords

Rumen; pouvoir hydrogène (pH); Microbial protein; Rumen ecosystem; Ruminant; Rumen microflora; Nutrient; Haematological parameters reference ranges; Healthy status.

Abbreviations

MBP: Microbial protein; MCP: Microbial crude protein; NDF: Neutral detergent fiber; NPN: Non-protein pitrogen; NSC: Nonstructural carbohydrate; OM: Organic matter; OMTDR: Organic matter truly digested in rumen; RDP: Rumen degradable protein; RUP: Rumen undegradable protein; SCFA: Short chain fatty acid; TDN: Total digestible nutrient; VFA: Volatile fatty acid; ATP: Adenosine Tri-phosphate; CP: Crude protein; CS: Concentrate supplementation; DM: Dry matter; DOMI: Dry organic matter intake; EMPS: Efficiency of microbial protein synthesis; FOM: Fermented organic matter.

Background
Urocystoliths are difficult to palpate and physical examination findings, complete blood cell count (CBC) and serum biochemical analysis are usually normal and the clinical signs are not definitive. Thus diagnostic imaging is a crucial tool required to confirm the diagnosis of urolithiasis in dogs presented with non-specific clinical signs of urogenital affection.

Aim
The aim of this study was to compare the capability of radiography and ultrasonography in detecting uroliths and concurrent urinary system abnormalities and to evaluate clinical, haematological and urinalysis findings of dogs affected with urolithiasis during the presentation.

Methods
Findings of signalment, history, physical and laboratory examination of blood and urine were performed and recorded. All dogs presented with complete or partial urinary obstruction, haematuria and renal failure were subjected to both radiographic and ultrasonographic evaluation. Uroliths were retrieved by a cystotomy, urethrotomy, and at necropsy from kidney failure cases confirming urolithiasis.

Results
The result revealed occult clinical haematuria in 56.5%, microscopic haematuria in 78.3% and dysuria/anuria in 34.8% of the affected dogs. Crystalluria is detected in seven (30.4%) of urolithiasis affected dogs. The total leukocyte count was significantly elevated (p≤0.05) in partially and completely obstructed dogs. Radiography diagnosed 19 of 23 urolithiasis cases in the urinary bladder (UB), 2 of 2 in the kidney and 12 of 13 in the urethra while ultrasonography diagnosed 17 of 23 urolithiasis cases in the UB and one in the urethra. From a total of 15 dogs presented with either neoplastic growth and/or cystitis concurrent with urolithiasis, ultrasound detected six while pneumocystogrpahy detected only one.

Conclusion
The study showed haematuria as the leading clinical sign of urolithiasis. Detection of urolithiasis and concurrent cystitis and/or urinary bladder growth increases when ultrasonography and radiography were employed together.