3 Comparison of hair cortisol levels and body temperature response prior to and post heat stress and water deprivation in Holstein dairy cows.

AbstractBody temperature responses and hair cortisol levels in dairy Holstein cows fed high- and low-forage diet and under water deprivation during thermal-humidity exposure (THE) were evaluated. Two experiments (Exps.) were conducted between July and September 2012 and 2013 for 64 d and 74 d, respectively. First, twenty dairy Holstein cows (90±30 DIM; 37.2±1.7 l milk/d, 620±75 kg BW) were used. The practical forage:concentrate (F:C) ratios in the low forage (LF) and high forage (HF) group were 44:56 and 56:44, respectively, while they were designed to be 40:60 and 60:40. Second, thirty dairy cows (53.5±30.4 DIM; 41.7±1.5 l milk/d,650±53 kg BW) were allotted into two groups of free access to water (FAW) and 2 h water deprivation (2hWD) following feeding. The animals were subjected to having the hair cut (1 to 2 g) from their foreheads at the same time (12:00 h) twice at the beginning (prior to the beginning of heat stress) and the end of the experiment when the cows were under THE. Hair cortisol levels (initial hair cut as the baseline and re-grown hair) were measured using ELISA method. Body temperature (BT) was measured twice daily at 7 body points of cows including rectum, vagina, hip, udder, rumen-side (flank), ear, and forehead using non-contact forehead infrared thermometer (infrared gun having two modes: inner and skin) on the 7 d of the beginning and the last 7 d of the experiment at 1000 and 1400 h. Statistical analyses were carried out using the MIXED model of SAS as repeated measurements. The intra-assay and inter-assay coefficients of variations for hair cortisol measurements were 3.15 and 10.05, respectively. Hair cortisol (HC) levels were not different within the two groups in both Exps. (P>0.05); however, HC level was lower (P<0.0001) prior to temperature-humidity exposure (THE). Results of Exp. 1 showed that vagina inner temperature was higher (P=0.041) and rectal temperature tended to be higher (P=0.083) in the HF compared to the LF group. The inner ear temperature was lower and ear skin temperature was higher (P=0.032) in the HF compared to the LF group. Forehead inner temperature was higher (P=0.048) in the LF group than in the HF group while forehead skin temperature was lower in the HF group (P=0.041). No differences were observed in the hip, udder and rumen-side (flank) temperature (both in body and skin) between the HF and LF group (P=0.012). In Exp. 2, no temperature differences were observed at all of the body points, inner and skin, between the two groups (P>0.05). However, the skin temperature in the 2hWD groups tended to be higher than in the FAW group (P=0.093). Conclusions drawn indicate the beneficial use of measuring BT at different body points of the cow in addition to RT under THE.

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Characterization of Short-Term Heat Stress in Holstein Dairy Cows Using Altered Indicators of Metabolomics, Blood Parameters, Milk MicroRNA-216 and Characteristics

Animals ◽

10.3390/ani11030722 ◽

2021 ◽

Vol 11 (3) ◽

pp. 722

Author(s):

Jang-Hoon Jo ◽

Jalil Ghassemi Nejad ◽

Dong-Qiao Peng ◽

Hye-Ran Kim ◽

Sang-Ho Kim ◽

...

Keyword(s):

Heat Stress ◽

Dairy Cows ◽

Milk Yield ◽

Milk Fat ◽

Blood Parameters ◽

Negative Effects ◽

Short Term ◽

Lactating Cows ◽

Humidity Index ◽

Holstein Dairy Cows

This study aims to characterize the influence of short-term heat stress (HS; 4 day) in early lactating Holstein dairy cows, in terms of triggering blood metabolomics and parameters, milk yield and composition, and milk microRNA expression. Eight cows (milk yield = 30 ± 1.5 kg/day, parity = 1.09 ± 0.05) were homogeneously housed in environmentally controlled chambers, assigned into two groups with respect to the temperature humidity index (THI) at two distinct levels: approximately ~71 (low-temperature, low-humidity; LTLH) and ~86 (high-temperature, high-humidity; HTHH). Average feed intake (FI) dropped about 10 kg in the HTHH group, compared with the LTLH group (p = 0.001), whereas water intake was only numerically higher (p = 0.183) in the HTHH group than in the LTLH group. Physiological parameters, including rectal temperature (p = 0.001) and heart rate (p = 0.038), were significantly higher in the HTHH group than in the LTLH group. Plasma cortisol and haptoglobin were higher (p < 0.05) in the HTHH group, compared to the LTLH group. Milk yield, milk fat yield, 3.5% fat-corrected milk (FCM), and energy-corrected milk (ECM) were lower (p < 0.05) in the HTHH group than in the LTLH group. Higher relative expression of milk miRNA-216 was observed in the HTHH group (p < 0.05). Valine, isoleucine, methionine, phenylalanine, tyrosine, tryptophan, lactic acid, 3-phenylpropionic acid, 1,5-anhydro-D-sorbitol, myo-inositol, and urea were decreased (p < 0.05). These results suggest that early lactating cows are more vulnerable to short-term (4 day) high THI levels—that is, HTHH conditions—compared with LTLH, considering the enormous negative effects observed in measured blood metabolomics and parameters, milk yield and compositions, and milk miRNA-216 expression.

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Infrared thermography to assess thermoregulatory reactions of buffaloes supplemented with antioxidant and dense energy source in summer season

Journal of Agrometeorology ◽

10.54386/jam.v23i3.23 ◽

2021 ◽

Vol 23 (3) ◽

pp. 243-248

Author(s):

YALLAPPA M. SOMAGOND ◽

S. V. SINGH ◽

ADITYA DESHPANDE ◽

PARVENDER SHEORAN ◽

V. P. CHAHAL

Keyword(s):

Heat Stress ◽

Body Temperature ◽

Infrared Thermography ◽

Rectal Temperature ◽

Control Group ◽

Group I ◽

Close Relationship ◽

Region Temperature ◽

Cortisol Levels ◽

Lower Magnitude

Twenty-four lactating buffaloes were chosen and subsequently divided into 4 groups i.e. group-I (control), group-II (supplemented astaxanthin at 0.25 mg kg-1 BW/day), group-III (prill fat at 100 g day-1), and group-IV (combination). Surface body temperature at different anatomical regions of buffaloes was recorded using infrared thermography (IRT), rectal temperature using a digital thermometer, and cortisol hormone by ELISA kit at the fortnightly interval. Forehead region temperature showed a higher correlation (0.390) with THI compared to other anatomical regions. The change in surface body temperature was positively correlated with THI and cortisol levels. The increase in the IRT temperature at different anatomical sites of buffaloes was at a lower magnitude in treatment groups compared to the control group. Udder surface temperature was higher in peak lactation and high producing buffaloes. Forehead region temperature showed a close relationship with rectal temperature and cortisol levels of buffaloes. According to the research findings, astaxanthin and prill fat can be used in ameliorating heat stress. Infrared thermography (non-invasive method) of the forehead and udder can be used as indicators for measuring the heat stress and production levels of buffaloes, respectively.

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Genetic variation of rectal temperature and its relationship to milk production in Holstein dairy cows

Proceedings of the British Society of Animal Science ◽

10.1017/s1752756200029021 ◽

2009 ◽

Vol 2009 ◽

pp. 63-63

Author(s):

S Khalajzade ◽

N Emam Jomeh ◽

A Salehi ◽

A Moghimi Esfandabadi

Keyword(s):

Heat Stress ◽

Dairy Cows ◽

Milk Production ◽

Heat Tolerance ◽

Rectal Temperature ◽

Weather Factors ◽

And Performance ◽

Very High ◽

Selection Of ◽

Holstein Dairy Cows

Milk production is significantly decreased by thermal stress. The survival and performance of an animal during heat stress periods depend on several weather factors, especially temperature and humidity. Researchers reported dramatic decreases in milk production as temperature rose above 30 degree of centigrade. Very high environmental temperature is common during the summer months in Iran. Rectal temperature is as indicator of heat tolerance and has been the most frequently used physiological variable for estimating heat tolerance in cattle. Some dairy cows are more heat tolerant and productive when subjected to heat stress. Identification and selection of heat stress resistant cattle offers the potential to increase milk yield in tropical environment. The aim of the present study was to estimate genetic parameters of heat tolerance and its relationship to milk production in Holstein Dairy Cows in Iran.

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