The relationship of estrus character before double dose artificial insemination in Limousin Crossbred cow

Ongole cattle in smallholder farms on Java, Indonesia, have been crossed with Limousin, which is not controlled repeatedly. The character of estrus affects the success of Artificial Insemination. This study aimed to determine the relationship between estrus characters before double dose artificial insemination using frozen semen sexing. The research was conducted in Senggreng Village, Sumber Pucung District, Malang Regency. The material was 45 head of Limousin crossbred cow inseminated using sexing semen produced by the Singosari National Artificial Insemination Center (SNAIC). The sexed semen processed with the Percoll Density Gradient Centrifugation (PDGC) method. The average body value of cows between 3-5 (scale 1-9) with an average age of 1.8-7 years, normal reproduction, clear signs of estrus. The reproductive organs were examined by rectal palpation to confirm that the cows are not pregnant. Parameters of estrus character were vulvar color, cervical mucus, vaginal temperature, pH, vulvar swelling, and heat detector value. The result showed that the estrus characters, including vulva color, vulva swelling, cervical mucus, vaginal temperature, cervical mucus pH, and heat detector score in the first and second artificial insemination have a low relationship. The regression models produced can be used but are less precise to estimate the relationship between estrus characters because the coefficient of determination shows a low influence.

Change of Ruminoreticular Temperature and Body Activity before and after Parturition in Hanwoo (Bos taurus coreanae) Cows

How do body temperature and activity change before and after parturition in pregnant cows? Changes in body temperature such as ruminal, rectal, and vaginal temperature during the parturition have been reported, but there are no results of the simultaneous observation of body temperature and activity. The aim of this study was to simultaneously confirm changes in the ruminoreticular temperature and body activity before and after parturition using the ruminoreticular bio-capsule sensor every 1 h. The 55 pregnant cows were used for the experiment, the ruminoreticular bio-capsule sensor was inserted and stabilized, and the ruminoreticular temperature and body activity were measured. The ruminoreticular temperature was lower by 0.5° from −24 h to −3 h in parturition compared to 48 h before parturition and then recovered again after parturition. Body activity increased temporarily at the time of parturition and 12 h after parturition. Therefore, the ruminoreticular temperature and body activity before and after parturition was simultaneously confirmed in pregnant cows.

Evaluation of different cooling management strategies for lactating Holstein × Gir dairy cows

Heat stress negatively impacts production, reproduction, and health of ruminants and strategies to alleviate these losses are warranted. Therefore, 4 experiments evaluated different cooling strategies on vaginal temperature (VT) of Holstein × Gir cows. Experiment 1 compared different amounts of water (2- or 4-L) over a 1-hour period from 1000 to 1100 h and 1600 to 1700 h. Experiment 2 evaluated the effects of sprinkling duration (in hours; 1- or 2-H), whereas Exp. 3 evaluated the effects of water amount (4- or 8-L) applied for 1- or 2-H. Lastly, the effects of a cooling strategy on specific hours of the day, starting at either 0700 (T-1) or 1100 h (T-2; Exp. 4), were evaluated. In all experiments, 12 Holstein × Gir cows were used in a 2 × 2 Latin Square Design containing 2 periods of 6 days each. Temperature and humidity index (THI) were recorded hourly and VT was recorded every 10-min throughout the experiments. As expected, an hour effect was observed for THI (P < 0.0001), which peaked early in the afternoon. In Exp. 1, a treatment × hour interaction was observed (P < 0.0001) for VT, as animals assigned to receive 4-L had a reduced VT at 1100, 1600, 1700, and 2300 h (P ≤ 0.03). During the cooling applications, cows receiving 4-L for 1 hour had a reduced VT from 60 to 150 minutes (P ≤ 0.04). In Exp. 2, a treatment × hour interaction was observed (P < 0.0001) for VT, as animals assigned to receive 4-L of water for 2-H had a reduced VT at 1200 h (P = 0.05). Moreover, during the cooling process, VT was reduced for 2-H cows from 140 to 170 min after the beginning of the cooling process (P ≤ 0.05). In Exp. 3, animals assigned to receive 4-L+2H had a reduced VT at 1200, 1700, 1800, and 1900 h (P < 0.001). A treatment × hour interaction was observed (P < 0.0001), as VT was reduced for 4-L+2-H cows from 130 to 180 min after the beginning of the cooling process (P ≤ 0.05). In Exp. 4, by the time when the first cooling cycle of T-1 was applied (0700 h), T-1 cows consistently had (P ≤ 0.05) a reduced VT up to the hottest hours and greatest THI of the day (1400 and 1500 h). This pattern was maintained until the end of the last cooling cycle, whereas T-2 cows had a reduced VT. In summary, 4 L of water over a 5-min cycle for a period of 2 hours twice a day maintained VT of Holstein × Gir cows at lower levels. Moreover, the hour at which the first cooling cycle starts also should be considered when evaluating the efficacy of a cooling strategy for an entire day.

PSX-B-27 Physiological changes in grazing dairy cows at increasing temperatures under moderate climate conditions

The continuous direct exposure to solar radiation, coupled with their own metabolic heat production, make grazing dairy cows on pasture particularly susceptible to heat stress. Heat stress can impair performance, animal welfare, and health. The objective of the present study was to identify physiological indicators of heat stress in dairy cows in a pasture-based production system under moderate climate conditions. The study was performed with 24 lactating Holstein dairy cows during summer 2018 and 2019 at the experimental farm of Agroscope (Posieux, Switzerland). Cows grazed full-time using a set stocking system. Climate conditions were recorded every min and were used to calculate the comprehensive climate index (CCI), which reflects the felt temperature in °C. The vaginal temperature (VT) of each cow was measured every 10 minutes with temperature loggers and was used as a physiological indicator of heat stress. Blood and milk were sampled once daily in the afternoon before and during milking, respectively. The concentrations of thyroxine (T4) and triiodothyronine (T3) were analyzed in blood plasma and cortisol concentration was analyzed in milk. Data from 12 periods of up to 3 consecutive days with increasing CCI was analyzed. Analysis were performed with the averaged CCI and the maximal VT recorded between 0830 and 1430 h. The VTmax was positively correlated with CCIaverage (P < 0.001). The T4 and T3 concentrations decreased with increasing CCIaverage and VTmax (P < 0.01). Cortisol concentrations were positively correlated with CCIaverage and VTmax (P < 0.05). Changes in VT and hormones showed that cows responded to increasing environmental temperature and may have perceived the rising heat load as a stressor.

Identification of Breed Differences in Known and New Fescue Toxicosis Associated Phenotypes in Charolais-and Hereford-Sired Crossbred Beef Cows

Beef cattle phenotypes are affected by the consumption of toxic fescue. Toxic fescue’s impact is dependent on heat stress and breed composition, with genetic variability for robustness to toxin exposure believed to exist within and across breeds. The study objective was to characterize the effect of fescue toxicosis across breeds for known and novel heat and fescue stress-associated phenotypes. One-hundred crossbred fall-calving Charolais- and Hereford-sired cows of parities 1–3 were allocated to graze either toxic fescue (n = 50), non-toxic fescue (n = 25), or a rotation between toxic and non-toxic fescue (n = 25) for 156 days. Phenotypes impacted by breed (genetics) included hair coat score (p < 0.0001), hair reduction/shedding rate (p < 0.05), rectal temperature (RT) (p < 0.0001), vaginal temperature (p < 0.05), serum phosphorus concentration (p < 0.02) and respiration rate (RR) (p < 0.003). Cows on toxic fescue experienced reduced hair shedding efficacy (p < 0.0001), higher vaginal temperatures (p < 0.0001), increased systolic blood pressure (p < 0.04), increased RR (p < 0.0001) and reduced average daily gain (p < 0.0001), compared to cows grazing non-toxic fescue. Calves born from cows with higher RT during the last third of gestation had higher RT at weaning (p < 0.02), indicating potential physiological effects of in utero heat stress. The study indicates that beef cows exhibit variable responses to toxic fescue within and across breeds which may impact future calf phenotypes.

Habituation Protocols Improve Behavioral and Physiological Responses of Beef Cattle Exposed to Students in an Animal Handling Class

Our objective was to determine the impact of different habituation protocols on beef cattle behavior, physiology, and temperament in response to human handling. Beef heifers were exposed to three habituation strategies: (1) tactile stimulation (brushing) in the working chute for seven consecutive days (STI; n = 18); (2) passage through the working chute for seven consecutive days (CHU; n = 19) and; (3) no habituation (CON; n = 19). Individual heifer respiratory rate (RR; n/min), internal vaginal temperature (VAGT; °C), and blood cortisol were measured. Further, behavior parameters were observed to generate a behavior score, and heifer interaction with students and their behavioral responses were recorded. Habituation with STI and CHU resulted in improved numerical behavioral scores compared to CON, and greater (p ≤ 0.05) handling latencies. Vaginal temperature was decreased in STI compared to CHU and CONT (p ≤ 0.05). Cortisol concentration did not differ among treatments, but decreased (p ≤ 0.05) from the start of the experiment to 14 days after treatment initiation. Both habituation protocols showed benefits, but heifers that received the positive tactile stimulation in the chute had the greatest behavior improvements. Furthermore, these heifers responded more calmly during student-animal interactions in class, which is beneficial for the students’ and animals’ safety.

Daily vaginal temperature in Girolando cows from three different genetic composition under natural heat stress

The present trial evaluated the effect of crossbred composition and Temperature and Humidity Index (THI) on vaginal temperature (VT) of Girolando dairy cows maintained under tropical pasture during warm seasons. The VT was monitored along 41 to 96 h in 615 Girolando cows with different Holstein (H) × Gir genetic composition (1/2 H = 284, 3/4 H = 248, and 7/8 H = 83) from six Brazilian farms in the summer of 2016 and 2017. VT of each cow at each hour of the day and the respective THI were averaged per hour across all monitoring days to generate an averaged value for VT and THI during 24 h. A linear mixed model with repeated measures using restricted maximum likelihood (REML) method for (co)variance components estimation procedure was employed. The final model adjusted the VT for the effects of cow, time, THI, farm, year, pregnancy status, body condition score (BCS), milk yield, genetic composition, and genetic composition*time interaction. Fixed effects were evaluated by ANOVA and tested with Tukey test in R software version 3.6.1 (R Core Team, 2019). Overall mean of VT, air temperature (AT), and THI were 39.06 ± 0.52 °C, 25.63 ± 0.40 °C, and 75.06 ± 3.96, respectively. VT had moderate positive correlation with THI (r² = 0.45, P &lt; 0.001) and AT (r² = 0.46, P &lt; 0.001). The VT had estimated linear increase of 0.05 °C for each THI unit increase (P &lt; 0.001). Least square mean of VT varied among the farms (P &lt; 0.001), pregnancy status (P &lt; 0.001), and BCS (P &lt; 0.05) but not for Milk yield (P &gt; 0.05). The daily average VT was affected by genetic composition (P &lt; 0.001) with highest temperature for 3/4 H (39.08 ± 0.06 °C a) and 7/8 H (39.09 ± 0.06 °C a) and lowest temperature for 1/2 H (38.95 ± 0.06 °C b). The difference of VT among the three crossbred groups varied in function of the time of the day, from 12:00 to 20:00 h (P &lt; 0.001), with 3/4 Holstein and 7/8 Holstein cows reaching similar VT, above to the upper limit 39.1 °C and higher than 1/2 Holstein cows during all this period. In conclusion, Girolando cows are sensitive to heat stress in tropical condition during warm seasons. Moreover, Girolando cows with genetic composition higher than 3/4 Holstein display reduced thermoregulatory efficiency. Therefore, Girolando cows in tropical dairy farms require strategies to mitigate heat stress according to their genetic composition.

Connecting Metabolism to Mastitis: Hyperketonemia Impaired Mammary Gland Defenses During a Streptococcus uberis Challenge in Dairy Cattle

β-hydroxybutyrate (BHB) has been associated with disease incidence in early lactation dairy cattle, but such associations do not demonstrate causation. Therefore, the objective of this study was to examine the effects of BHB during an intramammary Streptococcus uberis challenge. A secondary objective was to elucidate the mechanisms behind BHB effects on cytokine transcript abundance using the RAW 264.7 cell line. Late lactation multiparous dairy cows (n = 12) were continuously infused intravenously with either BHB to induce hyperketonemia (target concentration: 1.8 mM) or with saline (CON) for 72 h during a S. uberis intramammary challenge. Body temperature, dry matter intake (DMI), milk production, and milk S. uberis cfu were measured daily until one week post-challenge. Blood samples were collected during infusion to assess changes in metabolism (glucose, insulin, glucagon, NEFA, and cortisol) and systemic inflammation (IL-1β and SAA). Mammary biopsies were conducted at 72 h post-challenge to assess transcript abundance of inflammation-associated genes. BHB-infused cows exhibited a delayed febrile response, noted by a lesser vaginal temperature during the final day of infusion, followed by a greater vaginal temperature 6 d post-challenge. Consequently, BHB-infused cows had greater S. uberis cfu on d 4, 6, and 7 as compared to CON. Accordingly, BHB-infused cows consumed less DM, produced less milk, had reduced blood glucose, and had increased cortisol concentrations, however, no effects were seen on other systemic parameters or transcript abundance of inflammation-related genes in mammary tissue. To elucidate mechanisms behind the impaired immune defenses, RAW 264.7 cells were transfected with a GPR109A siRNA for 24 h and then treated with or without 1.8 mM BHB and challenged or left unchallenged with S. uberis for an additional 3 h. Transfection with siRNA reduced Gpr109a by 75%. Although BHB treatment did not significantly increase Il10, GPR109A knockdown as compared to the scrambled control reduced Il10 by 90% in S. uberis challenged macrophages treated with BHB, suggesting that macrophage immune responses to S. uberis can be altered via a GPR109A-dependent mechanism. Taken together, these data suggest that BHB altered the immune response promoting tolerance toward S. uberis rather than resistance.