Machine Learning to Predict Pregnancy in Dairy Cows: An Approach Integrating Automated Activity Monitoring and On-Farm Data.

Automated activity monitoring (AAM) systems are critical in the dairy industry for detecting estrus and optimizing the timing of artificial insemination (AI), thus enhancing pregnancy success rates in cows. This study developed a predictive model to improve pregnancy success by integrating AAM data with cow-specific and environmental factors. Utilizing data from 1,054 cows, this study compared the pregnancy outcomes between two AI timings-8 or 10 h post-AAM alarm. Variables such as age, parity, body condition, locomotion, and vaginal discharge scores, peripartum diseases, the breeding program, the bull used for AI, milk production at the time of AI, and environmental conditions (season, relative humidity, and temperature-humidity index) were considered alongside the AAM data on rumination, activity, and estrus intensity. Six predictive models were assessed to determine their efficacy in predicting pregnancy success: logistic regression, Bagged AdaBoost algorithm, linear discriminant, random forest, support vector machine, and Bagged Classification Tree. Integrating the on-farm data with AAM significantly enhanced the pregnancy prediction accuracy at AI compared to using AAM data alone. The random forest models showed a superior performance, with the highest Kappa statistic and lowest false positive rates. The linear discriminant and logistic regression models demonstrated the best accuracy, minimal false negatives, and the highest area under the curve. These findings suggest that combining on-farm and AAM data can significantly improve reproductive management in the dairy industry.

Farmers' Perceptions on Implementing Automatic Milking Systems in Large USA Dairies: Decision-Making Process, Management Practices, Labor, and Herd Performance.

Automatic Milking System (AMS) installations are increasing in the USA despite the higher investment cost than conventional systems. Surveys on AMSs conducted outside the USA focused on small-medium herds, specific regions, or aspects of AMS milking. This study described farmers' perceptions about the decision-making process of adopting an AMS in the USA's large dairies (≥7 AMS boxes) regarding changes in technology, housing, management practices, labor, herd performance, and health. After being contacted, 27 of 55 farmers from large AMS herds completed the survey. The main reasons for adopting an AMS were labor costs, cows' welfare, and herd performance. Most farms constructed new barns, used a free-flow traffic system, and changed their feed management. Increases in water and energy use were perceived by 42% and 62% of farmers, respectively. Farmers estimated decreases in labor costs of over 21%, and AMS employees worked 40-60 h/week. Milk production increases were reported by 58%, with 32% observing higher milk fat and protein content. Easier sick cow detection, better mastitis management, and improvements in pregnancy rates were reported. Thus, farmers transitioning to AMSs perceived altered resource utilization, labor cost savings, and improvements in employee quality of life, animal welfare, and farm management. While 54% of respondents would recommend an AMS to other farms, 38% suggested considering additional aspects prior to adoption.

Blastocoel fluid removal and melatonin supplementation in the culture medium improve the viability of vitrified bovine embryos.

In this study, we investigated the effects of melatonin supplementation in the culture medium and blastocoel fluid removal (BFR) before vitrification on the quality and viability of in vitro-derived bovine embryos. After fertilization, presumptive zygotes were assigned to one of the following treatments: control, in vitro standard culture (IVC) medium; IVC + M10-9, IVC medium supplemented 10-9 M melatonin; or IVC + M10-9 BFR, IVC medium supplemented with 10-9 M melatonin plus BFR on day 7 (D7) of culture. D7 blastocysts were vitrified by the Cryotop method and, after 5 mo of storage, were warmed and incubated for an additional 72 h. The re-expansion rate was evaluated after 2 and 24 h, and the hatching rate was evaluated after 24, 48, and 72 h. At 72 h, the total number of cells (TNC); number of apoptotic cells (NAC); and expression of genes related to oxidative stress (HSPA5), cell metabolism (SLC2A3), cell repair (MSH6), placentation (KRT8 and PLAC8), and implantation (FOSL1) were assessed in the blastocysts. Less than 30% of the control blastocysts re-expanded until 2 h, whereas more than 85% of the IVC + M10-9 and IVC + M10-9 BFR blastocysts re-expanded (P < 0.05). The hatching rate of IVC + M10-9 BFR blastocysts increased at all time points (P < 0.05), reaching 66.8% at 72 h of incubation. The TNC was similar among treatments (P > 0.05), regardless of vitrification/warming and re-cultivation. The NAC:TNC was smaller for melatonin-treated blastocysts (P < 0.05). BFR increased HSPA5 (P = 0.0118) expression and did not affect SLC2A3, MSH6, KRT8, and FOSL1 expression (P > 0.05). In conclusion, melatonin (10-9 M) supplementation in the culture medium and BFR on D7 of culture increased the hatching rate 24, 48, and 72 h after warming of the vitrified embryos, indicating an improvement in cryotolerance.

Taxa de concepção de vacas leiteiras submetidas à inseminação artificial em tempo fixo em diferentes épocas do ano / Conception rate of dairy cows submitted to fixed time artificial insemination at different seasons of the year

Objetivou-se avaliar a influência da época do ano sobre a taxa de concepção de diferentes categorias de vacas lactantes submetidas à inseminação artificial em tempo fixo (IATF). As vacas foram divididas nas categorias: multíparas de alta produção (MA), multíparas de baixa produção (MB) e primíparas de alta produção (PA). Foi comparada a taxa de concepção entre as vacas inseminadas no período de temperaturas mais amenas (TA) e no período de temperaturas mais elevadas do ano (TE), dentro de cada categoria animal. Foi utilizado o seguinte protocolo de IATF para todos os animais: D0 ­ implante de progesterona e 2 mg de benzoato de estradiol; D8 ­ retirada do implante de progesterona, 0,15 mg de cloprostenol sódico, 300 UI de gonadotrofina coriônica equina, 1 mg de cipionato de estradiol; D10 ­ 0,004 mg de acetato de buserelina e inseminação artificial após 48 horas da retirada do implante. O diagnostico de gestação foi realizado aos 30 e 60 dias após a IATF. Os dados foram analisados estatisticamente pelo Teste Exato de Fisher a 5% de significância (SAS, 2000). Não houve diferença estatística entre os grupos analisados. A época do ano não interferiu na taxa de concepção de vacas multíparas de alta produção, multíparas de baixa produção e primíparas de alta produção, nos diferentes períodos do ano.

The objective of the present study was to assess the influence of season of the year on conception rate of different categories of milking cows submitted to fixed time artificial insemination (FTAI). The cows were divided into the following categories: high production multiparous (MA), low production multiparous (MB) and high production primiparous cows (PA). The conception rate was compared between the cows inseminated in the period with mild temperatures (TA) and in the period with higher temperatures (TE), within each animal category. The following FTAI protocol was used for all the animals: D0 ­ progesterone implant, 2 mg of estradiol benzoate, D8 ­ progesterone implant removal, 0.15 mg of cloprostenol sodium, 300 UI of equine chorionic gonadotropin, 1 mg of estradiol cypionate; D10 ­ 0.004 mg of buserelin acetate and artificial insemination 48 hours after removing the implant. Pregnancy was diagnosed at 30 and 60 days after FTAI and the data was analyzed by the Exact Fisher test. There was no statistical difference in the conception rate of the cows inseminated at different seasons of the year in any categories analyzed. The season of the year did not interfere in the conception rate of high production multiparous cows, low production multiparous cows and high production primiparous cows.

The effects of progesterone treatment following artificial insemination on the reproductive performance of dairy cows.

The objective of this study was to examine the effects of increasing circulating progesterone in multiparous Holstein cows, using an intravaginal progesterone implant between days 3 and 7 following fixed-time artificial insemination (FTAI). The animals were randomly assigned into two groups: (1) treatment group and (2) control (no treatment). The experiment took place during periods of high and mild temperatures. Pregnancy rates were evaluated by ultrasound at 30 and 60 days after FTAI; embryonic and fetal mortality rates were also evaluated on these dates. The temperature and humidity index on the day of FTAI were different (P < 0.05) during the times of interest, but it did not affect conception rates. Neither the conception rates at days 30 and 60 nor the embryonic and fetal mortality rates differed between the groups during either the high- or mild-temperature periods (P > 0.05). Throughout the experimental period, the serum progesterone concentration was higher in the treatment group than in the control (P < 0.05). We conclude that the intravaginal progesterone implant inserted from days 3 to 7 following FTAI had no effect on conception rates at days 30 and 60 or on embryonic or fetal mortality rates but enhances the serum progesterone concentrations following treatment in multiparous Holstein cows during high- and mild-temperature periods.