Behavior and thermal comfort of light and dark coat dairy cows in the Eastern Amazon

Abstract

This study aimed to evaluate the behavior and thermal comfort of 20 Girolando cows (5/8-H/G), with light and dark coats, in the wettest period of the year, in Santarém, Pará, Brazil, in pasture with access to shade, and plenty of drinking water and mineral salt. Animal behavior categories were computed for 12 h a day, on 3 days in a row, by trained observers. Three day shifts were considered: Morning (6:00 a.m. to 9:55 a.m.), Intermediate (10:00 a.m. to 01:55 p.m.) and Afternoon (2:00 p.m. to 05:55 p.m.). The Temperature Index (TI), the Black Globe Humidity Index (BGHI) and the Comfort Index (CI) were calculated to measure thermal comfort. At all times studied, BGHI pointed that the environment was outside the thermal comfort zone. Dark-coated animals spent more 34.26% of the time in activities in the shade. The light-coated animals remained more 11.88% of the time in the sun, performing their natural behaviors. Both light and dark coat animals remained more 77 and 74.44% of the time in the sun, respectively. The behavior “in the sun while grazing” was the most evident, in both coats, in the studied shifts. The behaviors “in the shade while walking” and “in the shade while standing idle” were more evident (p < 0.01) in dark-coated cattle. The grazing behavior was higher in animals with dark coat (p < 0.05). In all evaluated shifts, there was a positive correlation between the behavior “in the sun while grazing” with the CI (r = 0.44211; p < 0.0305). Behaviors performed in the shade, such as “idleness while lying down,” “ruminating while lying down and standing up,” and behaviors “in the sun,” “idleness while lying down” and “ruminating while lying down,” were negatively correlated with CI. It is concluded that, even in the wettest period of the year, in the Eastern Amazon, Girolando dairy cows are exposed to hot environments, which causes thermal discomfort and changes in their natural behavior, as they spend more time standing in shaded areas, usually in rumination. Also, light-coated cows spend more time in the sun, while dark-coated cows spend more time in the shade. Thus, light-coated cows tend to have health and zootechnical performance negatively affected.

The effect of birth weight and time of day on the thermal response of newborn water buffalo calves

“…The nostrils showed significantly lower temperatures than those recorded in the ocular, lacrimal caruncle, and auricular regions. These results are attributed to the tachypnea response as a means of achieving thermoneutrality (64). In this regard, the increase in oxygen intake compensates for one of the main consequences of hypothermia; namely, hypoxemia (57,65).…”

Animal welfare and effects of per-female stress on male and cattle reproduction—A review

“…In 2004, the European Union presented the "Welfare Quality R Project", stimulating integration between researchers about AW from different institutions. Four approaches and 12 criteria were proposed (23), such as: Good nutrition, defined by absence of hunger and prolonged thirst (1 and 2); Good accommodation, for waiting (3) and providing thermal comfort (4), in addition to ease of movement (5); Good health, characterized by the absence of injuries (24), diseases (6), pain induced by handling (7); and present appropriate behavior, such as: the expression of social behavior (8), of other behaviors (9), in addition to having a good interaction between human and animal (10) and positive emotional states (11).…”

“…Several studies have been carried out to measure the effects resulting from microclimates that interfere with the thermal comfort of cattle, the main variables being measurable; temperature, humidity, wind speed and solar radiation that are used to determine the indices of thermal comfort in animals (7)(8)(9)(10)(11)(12)(13).…”

Thermographic Profiles in Livestock Systems under Full Sun and Shaded Pastures during an Extreme Climate Event in the Eastern Amazon, Brazil: El Niño of 2023

“…However, there are still systems where pastures are predominantly in full sun, with access to water only at drinking fountains [ 1 , 2 , 3 ]. A major scientific concern is reconciling animal welfare with productive performance in Brazilian livestock farming [ 4 , 5 , 6 , 7 ].…”