Price and warranty
Worldwide price for basic Ovi-bovi versionIn the basic version we guarantee 1 km range of wireless tag-to-receiver transmission in the worst case conditions (actual range is normally up to 2 to 5 km) and we also equip the tags with ISO 15693 complying microchips compatible with modern NFC-enabled smartphones and equipment installed on a farm (NFC scanners at selection gates, in milking parlors etc.) is $65 per tag + $1700 for the receiver unit, no subscription fee or additional hidden fees charged. The warranty period for Ovi-bovi tags and receivers is 5 years. Considering the benefits of implementing the cow monitoring system, its payback period in a typical farm at these prices is 1 year — and only because only cats breed that fast, not cows unfortunately.
We recommend equipping 35-40% of your milking herd—enough to ensure all cows and heifers eligible for breeding are wearing a tag. Tags can be removed from pregnant cows and immediately reused on those that have recently calved. The system is fully scalable: you can add more Ovi-bovi tags at any time.
Economics of estrus detection and ROI estimate
Reproductive issues may stem from poor herd health. This may be caused by an unbalanced diet—too much corn silage and concentrates aimed at a short-term milk boost—or from feeding rotten, poorly preserved forage (a common issue when weather forces a rushed harvest). But just as critical—and even more common—are missed heats and poorly timed inseminations in both cows and heifers.
The mainstream means of cow heat detection today is simple visual observation of the herd — sometimes assisted with pressure sensors or color markers attached mechanically to the cows’ tails, such as Kamar or EstroTect. In a small herd, detection rate of approximately 70% can be achieved with two or three observation periods of 30 min a day.J. H. Van Vliet & F. J. C. M. Van Eergenburg, “Sexual activities and oestrus detection in lactating Holstein cows,” Applied Animal Behaviour Science 50 (1996) 57–69. More recent and reasonable models assume heat detection rate of 60% for cows and 30% for heifersR. M. Demeter et al., “A multi-level hierarchic Markov process with Bayesian updating for herd optimization and simulation in dairy cattle,” Journal of Dairy Science 94 (2011) 5938–5962. or 50% on average and 70% in a “good” scenario.C. Inchaisri et al., “Economic consequences of reproductive performance in dairy cattle,” Theriogenology 74 (2010) 835–846. An assumption of 50% for heat detection rate on a typical large-scale farm seems quite generous thus — while years of Ovi-bovi system usage showed at least 90% of heat detection for cows in free-stall barns.
But it is not detection rate as such, but overall conception efficiency that directly determines breeding results and profitability in a herd. For a successful insemination, simply detecting a heat isn't enough—what truly matters is accurately determining when the heat began and timing the insemination accordingly to maximize the chances of pregnancy. When relying on visual observation alone, you have no way of tracking the progression of the heat (which typically lasts 10 hours or more), making it nearly impossible to pinpoint the optimal window for insemination. We assume first-service conception rates with this method hover around 50%. In contrast, farms using Ovi-bovi tags consistently achieve first-service conception rates of 67%. Overall, these numbers allow us to compare breeding efficiency in three senarios:
| Insemination upon visual heat detection | Insemination with Ovi-bovi tags | Hormonal synchronization protocol |
| If detection probability p1 = 50% and first-service conception probability p2 = 50% (with visual detection, it's difficult to pinpoint optimal insemination timing), then the overall probability of successful conception is p1 × p2 = 0.5 × 0.5 = 0.25 |
Years of operation show that with loose housing, Ovi-bovi tags achieve a heat detection probability of at least p1 = 90%, and first-service conception probability p2 = 67%. Overall probability of successful conception: p1 × p2 = 0.9 × 0.67 = 0.6 |
Let's take p = 45%—this is an overly optimistic estimate, achievable with imported drugs. When using low-cost alternatives (Surfagon instead of gonadoliberin, Magestrophan instead of cloprostenol), the probability of successful conception can drop to 0.3 |
| A herd of n cows requires n + (1−p)n + (1−p)2n + … = n/p inseminations, or an average of 1/p inseminations per cow. For the scenarios above, this equals: | ||
| 4.0 | 1.7 | 2.2 |
| The average extension of the calving interval (given a 21-day estrous cycle) compared to an imagined 100% conception efficiency would be (1/p − 1) × 21 days: | ||
| 63 days | 14 days | 26 days |
As the table shows, switching from visual observation to sensor-based detection and insemination delivers three key benefits: first, it roughly cuts semen usage in half; second, it reduces the average calving interval by 49 days; and third, it delivers a corresponding increase in calf crop.
We recommend attaching tags and beginning insemination from day 60 post-calving—this is the minimum physiological window, as earlier insemination risks incomplete involution of the reproductive tract, which drastically reduces fertility and increases the risk of embryonic mortality and pregnancy complications. Under this protocol, the average time to first detected heat is 60 + 21/2 = 70.5 days post-calving, the average service period is 70.5 + 14 ≈ 85 days, and the calving interval is 280 + 85 = 365 days—delivering an ideal 100 calves per 100 cows per year.
With a milk price of $0.5 per liter and a 10-liter daily difference between peak and late-lactation production, shortening the calving interval by 49 days generates an additional $245 per cow annually from milk alone (0.5 $/L × 10 L/day × 49 days). Add to this the savings on semen—especially significant when using sexed semen—plus the revenue from additional calves sold. We leave it to the reader to calculate those numbers for his case. The system pays for itself with good margin within the very first year of its use on the farm.
