Dairy Farm Evaluation: Water, Climate and Forage Before You Buy

Three eliminatory constraints for dairy viability

Unlike beef cattle or crop farming, where limiting factors reduce profitability gradually, dairy has three constraints whose absence makes the operation non-viable regardless of management quality or capital invested.

1. Water: the most frequently binding constraint

A Holstein dairy cow in production drinks 100-150 liters of water per day under normal thermal conditions. In heat stress (temperature above 25°C with high humidity), consumption rises to 150-200 liters per day. A 100-cow herd requires a minimum of 12,000-20,000 liters of potable or animal-quality water per day — before accounting for milking parlor sanitation, milk cooling and facility maintenance.

This means the aquifer status is structurally critical: not just whether water is available today, but whether the source is sustainable for the investment horizon. An overexploited aquifer or a well in a restricted extraction zone is a long-term viability risk even if pumping today.

Water distribution also matters: if the only water source is more than 2km from the milking area with no accessible shallow water table, operational costs and emergency water risk are serious practical constraints.

2. Climate: THI as the viability gate

The Temperature-Humidity Index (THI) combines ambient temperature and relative humidity to estimate heat stress on dairy cattle. The reference thresholds for specialized breeds like Holstein:

In tropical lowland zones of Mexico (coastal Veracruz, Tabasco, lowland Chiapas) and much of Central America, peak-month THI systematically exceeds 84 — making specialized Holstein dairy non-viable without intensive cooling infrastructure that fundamentally changes the cost structure. In contrast, Los Altos de Jalisco (Mexico's dominant dairy basin) has an altitude-moderated semi-arid climate that produces peak-month THI averages of 55-65, which is why it hosts roughly 30% of Mexico's commercial dairy production.

3. Forage: the technical-financial pivot

A high-producing Holstein cow (25-35 liters/day) requires 18-22 kg of dry matter of quality forage per day, supplemented with concentrate according to production level. If the farm cannot produce or access within economic distance the necessary forage volume — alfalfa, corn silage, sorghum-sudangrass — the sustainable herd size is smaller and the dairy economics change substantially.

Forage quality matters as much as quantity: alfalfa at 20% crude protein supports significantly higher production than low-quality grass silage at 8% crude protein on the same dry matter intake. The crop suitability of the land for high-quality forage crops is therefore a direct input into dairy viability.

The dairy economics: from site to herd to margin

The pivot between physical site quality and dairy financial performance is the sustainable herd size: how many cows in production the farm can support with its water, forage and climate. From that number, the economics follow:

• Daily total production: herd size × liters/cow/day (depending on genetics and feeding level).
• Gross revenue: daily production × milk price at the local collection basin.
• Production cost: feed + health + labor + infrastructure amortization + energy.
• Net margin: expressed per liter or per cow per day.

Milk price varies significantly by collection basin and buyer. In Mexico, Nestlé, LALA, Alpura and local cheese industries pay different prices in different regions. Verifying the current farmgate price in the specific basin is as important as evaluating the soil before any financial projection.