Behavioral Estrus Research Articles

Treating anoestrous and delayed pubertal Achai dairy cattle with Ferula jaeschkeana

Ferula Jaeschkeana is renowned for its application in human reproductive disorders and its estrogenic effects observed in laboratory animals. This study aimed to investigate the reproductive implications of Ferula Jaeschkeana (FJ) on animals exhibiting anestrus and delayed pubertal reproductive disorders. The experiment involved 24 Achai dairy cows divided into four groups based on different doses of Ferula Jaeschkeana i) FJ-0, serving as the control group; ii) FJ-30 receiving 30 g; iii) FJ-50 receiving 50 g; and iv) FJ-70 receiving 70 g of the product. The herb, prepared as a shade-dried powder, was administered orally to the animals as a bolus along with their regular feed. Consequently, 33.34% animals from the delayed pubertal heifer group and 75% from the anestrus multiparous animal group (54.16% of entire treated animals) displayed behavioral estrus manifestations such as restlessness, bellowing, and mounting. Physical changes, including vulvar swelling and mucus discharge, were observed in these animals. Additionally, a small percentage 8.33% of animals in the delayed pubertal heifer group and 58.33% of animals from the anestrus multiparous animal group attained pregnancy, as confirmed on day 90 post-breeding. Furthermore, a significant elevation in serum estradiol levels and a reduction in serum progesterone concentrations were noted in FJ-50 and FJ-70 groups compared to the control (FJ-0) and the FJ-30 group. Thus, it can be concluded from this study that administering 50 grams of Ferula Jaeschkeana herb roots or extract to anestrous and delayed pubertal Achai cows may induce hormonal alterations, promote behavioral estrus, and facilitate conception in this breed of cattle.

420 Automated identification and behavioral estrus detection in freestall-housed dairy cows using computer vision and machine learning: A two-layered algorithm approach

Abstract A critical aspect of dairy management involves maintaining accurate records of individual animals and promptly detecting estrus behavior, which is vital for successful breeding and reproductive outcomes. Recent advancements in precision livestock management, utilizing computer vision and machine learning technologies, have paved the way for automated and precise solutions in these areas. The objective of this study is to investigate the application of computer vision and machine learning for animal identification and behavioral estrus detection in dairy cows housed in freestall settings, employing a two-layered algorithmic approach. The research was conducted at the Joe Bearden Dairy Research Center, where a total of 10 lactating Holstein-Friesian cows were assessed across a 7-d trial period. For synchronization efforts, cows were provided a single injection of Prostaglandin F2α at trial initiation with expected estrus behaviors to be exhibited within the following 56 h. Continuous video was captured in 4k resolution using a five-camera closed caption media recording system strategically placed in the pen corners and over the feed bunk alleyway to capture multiple perspectives. Video data extrapolated into frames and manual annotation was utilized to generate the machine learning algorithm’s training data. Frames were randomly selected from a scattering of 56 h of video across all five camera viewpoints and down sampled to 384 x 640 p for both layers. A two-layer approach was employed utilizing an algorithm for each aspect of the study with the first model detecting the behavior, and the second model using the detected region of interest to identify specific cows. The first layer was trained on 682 frames and validated against 123 manually annotated frames. The second layer was trained on 102 frames and validated against 16 frames manually annotated for individual animals. Results demonstrated that the model used for mounting behavior identification has high precision (0.819) and recall (0.89), achieving a 0.926 mAP at an IoU of 0.5. This model achieved an F1 score of 0.86 at a confidence threshold of 0.268. The results demonstrated that the model used for individual animal identification across different classes achieved high precision (0.861) and recall (0.842), with a mAP of 0.897 at an IoU of 0.5. The F1 score for all classes was 0.89 at a confidence threshold of 0.788. In conclusion, these promising findings underscore the potential of computer vision and machine learning technologies to revolutionize dairy cow management practices. This innovative approach not only has potential to enhance operational efficiency, but also contributes significantly to improved reproductive management, thereby advancing precision and productivity in dairy operations.

STUDY ON SUBCLINICAL ENDOMETRITIS IN CATTLE OF KATHMANDU VALLEY BY USING WHITE SIDE TEST (WST)

The current investigation aimed to identify the different levels of nonspecific bacterial infection in the genitalia of repeat-breeding cattle of Kathmandu District using WST. A total of 307 crossbred Holstein Friesian cows were considered for this purpose, out of which 246 repeat-breeding cattle were under treatment and 61 cattle with normal cycle (control group) were artificially inseminated at their first service. Cervical mucus samples were collected 8 to 12 hours after the first signs of behavioral estrus, and subjected to a white side test (WST) and bacteriological examination. From the results of WST, it has been inferred that only 9(14.75%) animals in the control group were positive and the remaining 52(85.24%) were negative. However, the majority of repeat-breeding animals were positive 190 (77.22%)) and only 56 (22.76%) of animals were found negative. Microbiological examination of 190 samples revealed E.coli 54(28.421%), Staphylococcus spp. 39(20.526%), Streptococcus spp. 26(13.684%), Corynebacterium spp. 10(5.263%), Pseudomonas spp. 7(3.684%), Klebsiella spp. 9(4.736%), and mix bacterial growth 44(23.157%). The remaining 56 repeat-breeding cattle were negative with WST, possibly due to the absence of bacteria. Other causes may be viruses, placental retention, ovarian cysts, dystocia, etc. The findings of the present study divulge that WST may be utilized in the field to detect subclinical endometritis caused by bacteria.

Evaluation of Hormonal and Biochemical Profile of Ladakhi Cow during Estrous Cycle: The Future Perspective of Reproductive Management of Ladakhi Cow

The Ladakhi cow is an indigenous breed from Ladakh, India, and has a unique genetic makeup to adapt to high-altitude hypobaric stress. Furthermore, little study is available on examining the Ladakhi cow’s blood biochemicals and reproductive hormonal status during various stages of the estrus cycle. Hence, the current study was conducted on eight reproductively mature Ladakhi cows at the experimental dairy cattle unit in Leh-Ladakh, India, to determine the changes in serum biochemical and hormonal levels during the estrus cycle. The estrus behaviour was initially observed before the blood sampling on days 0 (the day the cow exhibited heat symptoms), 2nd, 8th, 17th, and 21st days. The serum was isolated for biochemical and hormonal profiling as per standard procedures using commercially available kits. The results revealed that serum biochemicals, viz. Ca, Fe, ALT, AST, ALP, TG, TP, Albumin, Glucose, UA, Creatinine, and Urea levels were within the normal range of cows at high altitudes. However, reproductive hormones, e.g. GnRH, FSH, LH, progesterone, estrogen, PGF2α, IGF-1, and Insulin varied from the reference level at different stages of the estrus cycle. This study’s findings have provided new insights into the serum biochemical and hormonal profiling of Ladakhi cows during the estrus cycle and this information may help to develop a reference range and baseline value for the serum biochemicals and hormonal levels of Ladakhi cows for other breeding programs and health monitoring.

Exploring the impact of exogenous Kisspeptin-10 on ovarian follicular development and estrus behaviour in Lakhimi cows of Assam

Exploring the impact of exogenous Kisspeptin-10 on ovarian follicular development and estrus behaviour in Lakhimi cows of Assam

Reproductive Performance of Estrus Pattern in Bachaur Cows of Bihar

Background: The Bachaur is a medium sized draft purpose breed mostly present in Madhubani, Darbhanga and Sitamarhi districts of Bihar and presently the breed is at the verge of extinction. Since no data is presently available regarding the estrus pattern in these cows therefore, present study was designed to document the oestrus intensity, estrus cycle length, estrus behaviour and duration of estrus in these animals. Methods: The total of nine healthy breeding Bachaur cows aged 3 to 5 years were maintained under identical managemental conditions.The estrous cycles of nine animals was synchronized using Cloprostenol Sodium @ 500 mg I/M (Pragma®, Intas, India) in cycling Bachaur cows. Estrus was detected in the morning and evening for external signs of estrus, estrus behavior, intensity of estrus, estrus duration and estrous cycle length. Result: In the present study, mounting or mounted by other animals was observed in more than 70% and sniffing, tried to lick and Flehmen’s reaction was observed in about 66.67% of treated cows. The other parameters like bellowing, restlessness, milk yield reduction, frequent micturition and Flehmen’s reaction were recorded in 44.44%, 55.56%, 44.44%, 55.56% and 66.67%, of animals, respectively. The most appreciable physical sign of estrus recorded was intense swelling of vulva (in 88.89%) however hyperaemia of vulva, copious estrual mucous discharge, pronounced tonicity of uterus, completely dilated os cervix and presence of large palpable follicle on the ovary was observed in 44.44%, 55.56%, 66.67%, 77.78% and 66.67%, of cows respectively.

Factors at Insemination and Subsequent Conception of Cattle under Heat-Stress Tie-Stall Environments

This research aimed to compare the conception rates among AI at 12, 24, and 36 h after estrus in cattle living in tie-stall barns in a tropical environment. The second study was to determine factors at insemination at 24 h after estrus, including secondary signs of estrus behavior, reproductive tract characteristics, and heat-stress factors, in relation to conception. The study was conducted on 22 tie-stall dairy farms in Chiang Mai, Thailand. After secondary signs of estrus were observed, all farmers were informed for data collection at the insemination time. Repeated logistic regression models were used to determine factors associated with conception. The results revealed that cattle inseminated 24 h after estrus detection had the highest conception rate (67.5%). The study also found that cattle with three or two secondary estrus signs before insemination had a higher risk of conception than those with only one sign. Interestingly, there was an increased risk of conception when sticky or no cervical mucus was observed during insemination (OR = 6.85 and OR = 5.96, respectively). Moreover, increases in body temperature and ambient relative humidity were related to a decrease in the chances of conception. This study recommends delaying insemination to 24 h after the initiation of secondary estrus signs. Multiple signs of estrus, sticky cervical mucus, and lower body temperature increased conception risk in dairy cattle living in tie-stall barns in a heat-stress environment.

Effect of prostaglandin treatment on the estrus behaviour, follicular and luteal morphometry and serum hormone profile in sub-estrus buffaloes during non-breeding season.

Sub-estrus buffaloes do not exhibit estrus signs despite being cyclic contributing to extended service periods and inter-calving intervals causing significant economic loss. The present study described the effect of synthetic prostaglandin (PGF2α) on estrus behaviour, follicular and luteal morphometry, and serum estradiol (E2) and progesterone (P4) profile in sub-estrus buffaloes during the non-breeding season. The incidence of sub-estrus was 38.4% during the non-breeding season. The sub-estrus buffaloes (n = 33) were divided into two groups, viz., Control (n = 16) and PGF2α treatment (Inj. Cloprostenol 500 μg, i.m., n = 17). Estrus induction response was significantly greater in the treatment (100 vs. 18.75%, p < .001), and a relatively greater proportion of animals conceived in the treatment group (29.41 vs. 6.25%, p = .08). The time elapsed to induction of estrus and insemination following treatment was significantly lower in the treatment group than control. A significant increment in the follicle diameter (9.72 ± 0.45 vs. 13.00 ± 0.45 mm, P < .0001) and serum estradiol (E2) concentration (66.01 ± 11.92 vs. 104.9 ± 13.21 pg/mL, p = .003) observed at the post-treatment period in the PGF2α treatment group. At the same time, CL diameter was reduced significantly at a higher regression rate in the PGF2α treated buffaloes than those of control. Of the responded buffaloes, only 30% showed high-intensity estrus attributed to the expulsion of cervico-vaginal mucus (CVM), uterine tonicity, micturition, and mounting response by a teaser bull. From this study, it can be concluded that the administration of PGF2α could induce estrus in the sub-estrus buffaloes during the non-breeding season. Behavioural changes, along with sonographic observation of POF, regressing CL, and serum E2 and P4 concentration would be useful to determine the right time of insemination in sub-estrus buffaloes during non-breeding season.

Effect of estrus behavior on the paint removal score of the sacral region of nulliparous Bos indicus

O objetivo deste estudo foi correlacionar o comportamento do estro com o escore de remoção de tinta da região sacral (ERT) e avaliar a associação do ERT com o número de montas e comportamentos secundários do estro em fêmeas nulíparas de Bos indicus. Vinte e quatro protocolos de inseminação artificial em tempo fixo (IATF) de três manejos foram implementados para investigação do objetivo do estudo. A comparação entre ERT 3 e ERT 2 revelou diferenças significativas nas variáveis ​monta recebidas, execução de monta, descanso de queixo, cheirar ou ser cheirada, lamber e ser lambida, favorecendo o grupo ERT 3 (P &lt; 0,05), indicando estro. Entretanto, a comparação entre ERT 2 e ERT 1 não resultou em diferenças significativas nas características citadas, exceto no ser cheirada (P &lt; 0,05), indicando ausência de estro para esses dois escores. O número de montas recebidas em ERT 2 e 1 foi insuficiente para apagar as marcações. Conclui-se que o ERT se mostrou um indicador eficiente da manifestação do estro. Os comportamentos de estro das vacas nulíparas na ERT 3 foram mais evidentes que os da ERT 1 e 2, e os comportamentos manifestados na ERT 1 foram semelhantes aos da ERT 2, indicando ausência de comportamento de estro. Assim, sugere-se que no futuro o ERT seja apenas dividido em duas classes.

Effect of prostaglandin alone and in combination with trace minerals on the follicular and luteal dynamics, estrus response and pregnancy in sub-estrus buffaloes (Bubalus bubalis).

Sub-estrus is a condition when buffaloes do not display behavioural estrus signs, despite being in estrus and causes a delay in conception and increases the service period. The present study describes the effect of synthetic prostaglandin (PGF2α) alone and in combination with trace minerals on the follicular and corpus luteum (CL) dynamics, serum estradiol (E2) and progesterone (P4) concentration correlating estrus response and pregnancy outcome in sub-estrus buffaloes during the breeding season. A total of 50 sub-estrus buffaloes, identified through ultrasonography (USG) examination, were randomly allocated into three groups, viz. T1 (Synthetic PGF2α, Inj. Cloprostenol 500 μg, i.m, n = 17), T2 (Synthetic PGF2α + Trace mineral supplementation, Inj. Stimvet 1 mL/100 kg body weight, i.m., n = 17) and control (untreated; n = 16). Following treatment, 100% of sub-estrus buffaloes were induced estrus in the T1 and T2 groups, while only 18.75% were induced in the control. The CL diameter and serum P4 concentration were significantly lower at post-treatment, whereas the pre-ovulatory follicle (POF) size and serum E2 concentration were significantly higher in the T1 and T2 groups as compared to the control (p < .05). The buffaloes of the T2 group had a greater proportion of moderate intensities estrus than those of T1. Moreover, the proportion of buffaloes conceived in the T1 and T2 were 41.2% and 52.95%, respectively. The larger POF diameter and higher serum E2 concentration were associated with intense intensity estrus and higher conception rate (66.7%) in sub-estrus buffaloes. Similarly, CL regression rate, POF size and serum E2 concentration were relatively higher in the buffaloes conceived as compared to those not conceived. It is concluded that synthetic PGF2α in combination with trace minerals induces moderate to intense intensities estrus in a greater proportion of sub-estrus buffaloes and increases the conception rate during the breeding season. Moreover, behavioural estrus attributes correlating follicle and luteal morphometry, serum E2 and P4 concentration could be used to optimise the breeding time for augmenting the conception rate in sub-estrus buffaloes.

Early prediction of oestrus for herd fertility management in cattle and buffaloes - a review.

Oestrus is defined as a period when a female animal exhibits characteristic sexual behaviour in the presence of a mature male. Oestrous manifestation in dairy animals is due to the oestrogen (E2) effect on the central nervous system (CNS). It is a critical issue to be considered on a priority basis. Inefficient oestrous detection reduces the fertility status of the herd. The primary and most reliable indicator of oestrus is standing to be mounted by a bull or another female herd mate, signalling receptivity and the pre-ovulatory state in dairy cattle. Oestrous detection is primarily a management challenge requiring skill and vigilance. To improve the efficiency of oestrous detection in dairy cattle, visual observation is one of the best methods if done three times a day; however, heat detection aids, if combined, give better results. However, techniques like using teaser bulls, tail painting, chin ball markers, ultrasound (USG) examination, hormonal analysis and examination of cervicovaginal mucus (CVM) improve oestrous detection efficiency. Moreover, the changes in production systems have reduced the expression of oestrous behaviour among cows, due to higher oestrogen (E2) metabolism. Therefore, automated systems, such as pedometers, accelerometers and acoustic sensors like infrared thermography (IRT) and image processing, have significantly enhanced reproductive performance by facilitating oestrous detection and optimizing insemination schedules. From this review, we would conclude that oestrous detection alone contributes considerably to the reproductive status of the herd; therefore, applying different methods of oestrous detection reduces the incidence of missed oestrus and improves the fertility status of the herd.

Assessing Postpartum Reproductive Health via Endometrial Cytology and Body Temperature in Mehsana Buffaloes

The aim of this study was to investigate the effect of body temperature and endometrial cytology on postpartum reproductive health in Mehsana buffaloes. A total of twenty-six Mehsana buffaloes were used in this study. Per-rectal and ultrasonography examinations were used to observe the postpartum reproductive function of these buffaloes and on day 60 post natural service, the pregnancy was confirmed. Based on fertile estrus, buffaloes were retrospectively divided into two groups: Group I (buffaloes conceiving before 90 days) and Group II (buffaloes conceiving after 90 days). One week before parturition and four weeks after it, the rectal temperature was taken. The cytobrush technique was used to obtain endometrial samples for cytological tests on the 21st and 30th day postpartum. During the final week of pregnancy and the first, second, third, and fourth weeks’ post-partum, the mean rectal temperature (⁰F) varied from 101.7 ± 0.07 to 102.0 ± 0.06 in Group-I and 101.6 ± 0.07 to 102.1 ± 0.05 in Group-II. During the final week pre-partum and the first week post-partum, the mean rectal temperature (⁰F) was shown to be significantly (p&lt;0.05) lower than it was during the second, third, and fourth weeks post-partum among the groups. On the 21st and 30th day postpartum during endometrial cytology, the percentage of neutrophils was 14.31 ± 1.56 and 12.23 ± 0.93 in Group I and 17.92 ± 1.51 and 15.08 ± 0.73 in Group II, respectively. On the 30th day, there was a significant difference (p&lt;0.05) between the groups in Group II that had a greater mean percentage of neutrophils. When endometrial cytology was performed on buffaloes at various postpartum days, the mean percentage of lymphocytes, endometrial epithelial cells and large vacuolated epithelial cells revealed non-significant changes. On the 30th day, it was discovered that the prevalence of subclinical endometritis in Group I and Group II buffaloes was 7.69 and 23.07 percent, respectively. The postpartum first behavioural estrus and first fertile estrus occurred at 62.00 ± 4.34 and 65.31±4.45 days in Group I and 77.46±11.12 and 130.08±9.26 days in Group II buffaloes, respectively. Although, the average days for first behavioural estrus did not differ significantly between the groups the fertile estrus occurred significantly (P&lt;0.05) delayed in Group II buffaloes.

ShuYu capsule alleviates emotional and physical symptoms of premenstrual dysphoric disorder: Impact on ALLO decline and GABAA receptor δ subunit in the PAG area

Premenstrual dysphoric disorder (PMDD) is a severe subtype of premenstrual syndrome in women of reproductive age, with its pathogenesis linked to the heightened sensitivity of type A γ -aminobutyric acid receptors (GABAAR) to neuroactive steroid hormone changes, particularly allopregnanolone (ALLO). While a low dose of fluoxetine, a classic selective serotonin reuptake inhibitor, is commonly used as a first-line drug to alleviate emotional disorders in PMDD in clinical settings, its mechanism of action is related to ALLO-GABAA receptor function. However, treating PMDD requires attention to both emotional and physical symptoms, such as pain sensitivity. This study aims to investigate the efficacy of ShuYu capsules, a traditional Chinese medicine, in simultaneously treating emotional and physical symptoms in a rat model of PMDD. Specifically, our focus centres on the midbrain periaqueductal grey (PAG), a region associated with emotion regulation and susceptibility to hyperalgesia. Considering the underlying mechanisms of ALLO-GABAA receptor function in the PAG region, we conducted a series of experiments to evaluate and define the effects of ShuYu capsules and uncover the relationship between the drug's efficacy and ALLO concentration fluctuations on GABAA receptor function in the PAG region. Our findings demonstrate that ShuYu capsules significantly improved oestrous cycle-dependant depression-like behaviour and reduced stress-induced hyperalgesia in rats with PMDD. Similar to the low dose of fluoxetine, ShuYu capsules targeted and mitigated the sharp decline in ALLO, rescued the upregulation of GABAAR subunit function, and activated PAG neurons in PMDD rats. The observed effects of ShuYu capsules suggest a central mechanism underlying PMDD symptoms, involving ALLO_GABAA receptor function in the PAG region. This study highlights the potential of traditional Chinese medicine in addressing both emotional and physical symptoms associated with PMDD, shedding light on novel therapeutic approaches for this condition.

TWO SEXUALLY ACTIVE BUCKS HOUSED WITH FOUR SUCCESSIVE GROUPS OF ANOVULATORY DOES INDUCED HIGH PREGNANCY RATES DURING SEVEN-DAY MATING PERIODS

&lt;p&gt;&lt;strong&gt;Background.&lt;/strong&gt; In seasonally anovulatory goats, sexually active bucks led a high pregnancy rate during a mating period of 36 days. Progesterone priming of does can reduce the length of the mating period while maintaining high fertility by allowing oestrous behaviour at the first male-induced ovulation. &lt;strong&gt;Objective.&lt;/strong&gt; To determine whether high fertilization rates could be achieved by using two sexually active bucks, alternated daily for a period of seven days in four successive groups of does. &lt;strong&gt;Methodology.&lt;/strong&gt; Two control bucks were used only with one group of does (&lt;em&gt;n&lt;/em&gt; = 19), whereas two experimental bucks were successively housed with four groups of does (&lt;em&gt;n&lt;/em&gt; = 18 or 19 each). One of the control and experimental bucks was introduced to their respective groups in the morning and removed 24 h later to rest for 24 h. Immediately after the removal of the first buck, the second buck was placed with the group of does. Each doe was treated with 25 mg of progesterone im 48 h prior to the first introduction of bucks to reduce short ovulatory cycles. &lt;strong&gt;Results.&lt;/strong&gt; In each group, the proportion of does that ovulated was higher than 93%. These proportions did not differ among groups exposed to the control or experimental bucks (&lt;em&gt;P&lt;/em&gt; &amp;gt; 0.05). In each group, the proportion of pregnant does was higher than 78%; proportions did not differ among groups (&lt;em&gt;P&lt;/em&gt; &amp;gt; 0.05). &lt;strong&gt;Implications. &lt;/strong&gt;At farms with few bucks, efficient management of sexually active bucks can yield a high percentage of pregnant females. &lt;strong&gt;Conclusion.&lt;/strong&gt; These results indicate that two sexually active bucks housed with four successive groups of progesterone-treated anovulatory does during a mating period of seven days were able to achieve high pregnancy rates.&lt;/p&gt;&lt;div id="gtx-trans" style="position: absolute; left: -60px; top: -20px;"&gt; &lt;/div&gt;

Effect of GnRH and hCG Treatment Following a Short-Term Estrus Synchronization Protocol on Ovulation and the Fertility in Merino Ewes, During the Breeding Season

This study aimed to compare the effect of hCG or GnRH administered 36 h following a short-term estrus synchronization treatment on the ovulation time and pregnancy rates of Merino ewes during the breeding season. The estrus cycles of ewes were synchronized with an intravaginal sponge containing 60 mg of medroxyprogesterone acetate for 6 days, and an injection of 400 IU of eCG and 125 µg of d-cloprostenol 24 h before sponge removal. Thirty-six h after the sponge removal, ewes were injected intramuscularly either 1 ml of physiological saline solution (control-group; n=14), 100 IU of hCG (hCG-group; n=14) or 0.004 mg of buserelin acetate (GnRH-group; n=14). The estrus behavior was observed using teaser rams and the ovulation time was monitored using transrectal ultrasonography twice daily for 96 h after the sponge removal. Ewes in estrus were allowed a single mating using fertile rams. Estrus response was higher (P&lt;0.05) in the control group (92.86%) than in the GnRH group (50.00%). The interval from sponge removal to ovulation and from hCG to ovulation were shorter in the control group than in the hCG group (70.55, 80.83 h; 34.55, 44.83 h, respectively, P&lt;0.05). In conclusion, administration of hCG or GnRH at 36 h following a short-term estrus synchronization protocol did not affect estrus behaviors, ovarian findings and pregnancy rates in ewes during the breeding season.

Relationship of length of the estrous cycle to antral follicle number in crossbred beef heifers.

Length of the menstrual cycle was positively associated with antral follicle number in women. If this pattern is consistent in cattle, a value-added benefit to using automated activity monitors to determine estrous status could be the ability to predict antral follicle count (AFC). We, therefore, hypothesized that as inter-estrous interval increased ultrasonographic AFC would be greater in crossbred beef heifers. Over 3 yr, crossbred beef heifers (n = 1,394) were fitted with automated activity monitors for 81 d. From days 42 to 46, heifers were submitted for ultrasonographic examination to determine AFC. From days 60 to 81, heifers were visually observed twice daily for 45min for signs of behavioral estrus. Heifers that had a behavioral estrus that coincided with a sensor-based estrus and had a previous sensor-based estrus between 15 and 26 d earlier were used for the analysis (n = 850). A combination of regression analyses and correlation analyses were applied to understand the association between data collected by sensors and follicle number determined by ultrasonographic examination. Antral follicle count was analyzed using the GLM procedure of SAS with estrous cycle length (15 to 26 d) as a fixed effect. Estrus was more likely to initiate in the early morning hours and peak activity was greater (P < 0.0001) when estrus initiated between 0200 and 0800 hours then when estrus initiated at other times of the day. Antral follicle count did not differ due to length of the estrous cycle (P = 0.87). Thus, length of the estrous cycle obtained from three-axis accelerometers cannot be used to predict follicle number in crossbred beef heifers; however, machine learning approaches that combine multiple features could be used to integrate parameters of activity with other relevant environmental and management data to quantify AFC and improve reproductive management in beef cows.

Access to an outdoor open pack promotes estrus activity in dairy cows.

Dairy cows have a partial preference to access an outdoor deep-bedded pack, but the effects of continuous access to an outdoor area on estrous behaviors has not been studied. Our objective was to investigate if access to an outdoor open deep-bedded pack improves the expression of estrus behaviors. We enrolled 60 lactating Holstein cows directly after calving and followed them each for 12 weeks. Cows were housed in a single freestall pen holding 36 cows at a time, with a dynamic group composition. Half of the cows were randomly assigned to the OUTDOOR treatment; these cows had access to an outdoor open pack via an automated selection gate. INDOOR cows were housed together with OUTDOOR cows but were not allowed outdoor access. All cows were fitted with an automated activity monitor (AAM) 21 ± 3 d before expected calving date. Estrous behaviors (i.e., standing to be mounted and mounting behaviors) were continuously monitored using video, and the intensity of mounting (i.e., the number of standing to be mounted and other mounting behaviors per hour) was calculated per estrus event per cow. Temperature and humidity were monitored by data loggers indoors, and these data were used to calculate the Temperature Humidity Index (THI). Following an alert from the AAM, cows were checked to detect the presence of a dominant preovulatory follicle and an absence of a mature corpus luteum (CL) by rectal ultrasonography following milking, as well as 7 d thereafter to confirm ovulation by the presence of a new CL. A total of 94 estrus events were used in the final analysis. INDOOR cows tended to have a lower mounting intensity with increasing indoor THI, but no such effect was noted for OUTDOOR cows. The total number of cows in estrus positively influenced mounting intensity. OUTDOOR cows had a longer duration of estrus, as measured by the automated monitors, compared with INDOOR cows (12.4 ± 0.7 h versus 9.9 ± 0.8 h). Estrus event number and the total number of cows in estrus were both positively associated with estrus duration. These results indicate that access to an outdoor pack tended to increase mounting behavior for freestall housed dairy cows, especially during periods of elevated THI. We conclude that providing dairy cows access to an outdoor area can help with estrus detection and may thus help improve the reproductive programs on dairy farms.

Social effects on behaviorally-scored and pedometer-detected estrus in beef cattle.

The number of cows in estrus often influences estrus behavior; however, the effects of social order are not well documented. This study examined the effects of social order on the expression of behaviorally-scored and pedometer-detected estrus, combined with the effects of the number of cows in estrus. In a herd comprising 13 or 15 beef cattle, cows with orders 1st-7th were defined as dominant and the remaining cows as subordinate. Sole or simultaneous estrus was induced by prostaglandin F2α analog injection and/or intravaginal progesterone treatment. Ovulation timing was determined using ultrasonography at 6-hour intervals. Estrous signs and steps of the cows were recorded 49 h before ovulation using video monitoring and a pedometer, respectively. Among the 59 treated cows, 56 behaviorally-scored estruses (27 sole and 29 simultaneous) were detected. In the sole estrus, 61.5% of the dominant-rank cows had no zero-point period; however, 35.7% of the subordinate-rank cows had that period. The dominant-rank cows in estrus alone had a significantly shorter duration of scored estrus than those in simultaneous estrus (P < 0.05). Among the 50 pedometer-detected estruses (24 sole and 26 simultaneous), the subordinate-rank cows in sole estrus had a shorter interval from estrus onset to ovulation than the dominant-rank cows in simultaneous estrus (P < 0.05). The effects of social order varied in response to the number of cows in estrus, which might have influenced determining the optimal time for artificial insemination.

EL RETORNO AL ANESTRO, LAS PÉRDIDAS EMBRIONARIAS Y LOS ABORTOS COMO PRINCIPALES CAUSAS QUE REDUCEN LA FERTILIDAD DE LAS CABRAS SOMETIDAS AL EFECTO MACHO

&lt;pre&gt;&lt;strong&gt;Background.&lt;/strong&gt; In anestrous goats exposed to sexually active male goats ("male effect"), more than 90% display estrus and ovulate, but only 70% give birth. &lt;strong&gt;Objective.&lt;/strong&gt; To determine the causes that reduce fertility at birth of goats exposed to the male effect. &lt;strong&gt;Methodology.&lt;/strong&gt; Twenty-nine goats in seasonal anestrus that had a body condition of 1.3 ± 0.05 were used. Three adult male goats were exposed from November 1 to January 15 to artificial long days (16 h of light per day) followed by natural photoperiod. The three males were introduced into the group of goats on March 29, remaining with them for 15 days. Subsequently, from day 16 (April 13), only one male provided with a ventral harness to prevent copulation remained with the females until the end of the observations. Estrus, ovulations, pregnancies and their evolution over time were determined. &lt;strong&gt;Results.&lt;/strong&gt; All goats were detected in estrus, and 28 of 29 ovulated. Most of the goats (23/29) were diagnosed pregnant 38 days after the introduction of males, and this proportion did not differ from that registered at 72 days (18/29; P = 0.09). Of the 23 females diagnosed pregnant at 38 days, 16 gave birth. Of the 13 goats that did not give birth, six returned to the anestrus after having presented estrus behavior associated or not with ovulations; four lost the embryo between days 45 and 58; one was diagnosed as pseudopregnant at 58 days and two aborted at 95 and 129 days of pregnancy. &lt;strong&gt;Implications.&lt;/strong&gt; These results show that fertility at kidding is reduced in goats exposed to sexually active male goats, most likely due to the low body condition of the females. A nutritional supplementation could improve the fertility of females exposed to the male effect. &lt;strong&gt;Conclusion.&lt;/strong&gt; The results obtained in this study allow us to conclude that returning to anestrus, embryo losses and abortions reduce the fertility of goats subjected to the male effect during the seasonal anestrus.&lt;/pre&gt;

Occurrence of Postpartum Anestrus and Estrus Behaviour in Hormonal Treated Buffaloes of Jabalpur

The present study was conducted during June to December, 2022 at the Department of Veterinary Gynaecology and Obstetrics, College of Veterinary Science and Animal Husbandry, Nanaji Deshmukh Veterinary Science University, Jabalpur, Madhya Pradesh, India to study the occurrence of postpartum anestrus and compare the intensity of estrus in anestrus and estrus induced buffaloes of Jabalpur (M.P.). A total of 120 postpartum buffaloes (5–10 years of age) reared under field conditions in the Jabalpur district of Madhya Pradesh were surveyed. The buffaloes with a history of not showing signs of estrus for 60 days or more postpartum were considered as open animals for the study of the occurrence of postpartum anestrus. Gynaeco-clinical examination was also carried out to know the status of ovaries (presence of follicle or corpus luteum). These animals were randomly divided into four groups (three treatments and one control group) and each group had 06 anestrus buffaloes. Group I, II and III were treated with CIDR plus Ovsynch, CIDR plus Cosynch and eCG plus Cosynch protocols, respectively, while the control group (Group IV) animals were not given any treatment. The results revealed that the occurrence of postpartum anestrus in buffaloes was 69.10%. The percentage of postpartum buffaloes with 60–90 days, 90–150 days and more than 150 days postpartum were recorded to be 25.30, 45.78 and 28.91%, respectively. Irrespective of treatment groups, the overall estrus intensity ranged from 58–92 with a mean estrus intensity score of 70.58±2.89. Estrus intensity scoring is a good tool to describe the intensity of estrus which has a positive relationship with fertility.