Bone turnover markers in sheep and goat: A review of the scientific literature

Abstract

Bone turnover markers (BTMs) are product of bone cell activity and are generally divided in bone formation and bone resorption markers. The purpose of this review was to structure the available information on the use of BTMs in studies on small ruminants, especially for monitoring their variations related to diet, exercise, gestation and metabolic lactation state, circadian and seasonal variations, and also during skeletal growth. Pre-clinical and translational studies using BTMs with sheep and goats as animal models in orthopaedic research studies to help in the evaluation of the fracture healing process and osteoporosis research are also described in this review. The available information from the reviewed studies was systematically organized in order to highlight the most promising BTMs in small ruminant research, as well as provide a wide view of the use of sheep and goat as animal models in orthopaedic research, type of markers and commercial assay kits with cross-reactivity in sheep and goat, method of sample and storage of serum and urine for bone turnover markers determination and the usefulness and limitations of bone turnover markers in the different studies, therefore an effective tool for researchers that seek answers to different questions while using BTMs in small ruminants.

Experimental Exposure to Bisphenol A Has Minimal Effects on Bone Tissue in Growing Rams—A Preliminary Study

“…Even when we tried to eliminate or control most of the possible disrupting factors (diet, age, sex, breed, housing, season, circadian rhythm, climate, time of blood collection, location and storage, methodology, prior validation) [ 46 ], their variability was significant. Similar observations have been reported in previous studies in sheep [ 35 , 42 , 43 , 62 , 63 ]. No effect on bone turnover markers was observed in lambs exposed to zeranol and ewes exposed to sewage sludge on pasture, despite differences in bone geometry [ 62 ], mineral density, and biomechanics [ 35 ].…”

“…Bone turnover markers showed a wide interanimal variation in this study (including preexperimental values). P1NP levels were expected to increase, reflecting increased bone formation with growth, whereas CTX-I levels indicate a bone resorption process [ 42 ]. After BPA exposure, stimulated proliferation and collagen accumulation could be expected in osteoblasts but not in osteoclasts [ 17 ], whereas negative effects such as apoptosis, pyroptotic death, and autophagy were induced in osteocytes [ 40 , 41 ].…”

“…Serum basic biochemistry was determined using an automated chemical analyzer (Olympus Corp., Hamburg, Germany). Bone turnover markers were selected as previously reported [ 42 , 56 ], and commercially available kits were used to measure their serum levels, i.e., the Sheep Crosslaps (CR) Elisa Kit (MBS7240838, MyBioSource, CA, USA) and the Sheep Total Procollagen Type I Intact N-terminal Propeptide (TP1NP) Elisa Kit (MBS9358461, MyBioSource, San Diego, CA, USA). When the bone turnover marker CTX-I was analyzed, two serum samples (one sample per experimental group) were hemolytic and had to be excluded from further analysis.…”

“…Sheep are suggested as a suitable model for experimental orthopedic studies in humans, given their similarities in bone biochemistry and mineral composition, trabecular bone structure, modeling, and biomechanics. Most ossification centers of long bones close between 12 and 30 months of age (the distal center of the femur between 18 and 26 months of age) [ 42 , 43 , 44 ]. Thus, the study was conducted in rams aged 9–12 months with active EGP.…”

Curcumin Promotes Femoral Fracture Healing in a Rat Model by Activation of Autophagy

“…The process of fracture healing is affected by various factors with bone cell (osteoblast) activity and nutrient supply being two important factors [ 21 , 22 ]. To further evaluate the effect of curcumin on fracture healing, the osteoblasts were observed histologically.…”