The Effect of Abnormal Reproductive Tract Discharge on the Calving to Conception Interval of Dairy Cows

Abstract

Prolonged calving-to-conception interval (CCI) can increase economic loss in cattle. We investigated the effect of post-calving abnormal reproductive tract discharge (ARTD) on CCI in dairy cows and quantified the relationship of ARTD and associated risk factors with CCI. The source population was dairy cows that calved in the study period on three pasture-based, year-round calving farms in the Riverina, NSW, Australia. Farm records and records from veterinarians' visits were analyzed. ARTD was defined as the presence of reproductive tract discharge according to the following classification: per vaginum purulent discharge ≥21 days post-calving or mucopurulent discharge >26 days post-calving. The incidence of ARTD was calculated. A Kaplan-Meier survivor function was used to estimate median time to conception post-calving dependent on the presence or absence of ARTD. Mixed effects Cox-proportional hazard models were used to estimate the direct and indirect effects of ARTD, and other potential risk factors on CCI such as body condition score (BCS), ambient temperature, and milk yield. Model structures were guided by a directed acyclic graph of potential risk factors for ARTD. The incidence of ARTD in lactations was 16% (95% CI 13.8–18.5%) and did not differ significantly between the three farms (P > 0.05). The median CCI was 176 and 118 days for lactations with and without ARTD, respectively (P < 0.01). The rate of pregnancy following calving in cows with ARTD was significantly decreased relative to the rate of pregnancy in cows without (total effect hazard ratio = 0.62, se = 0.18, P = 0.01). High peak milk yield (>32 L) and parity >2 also significantly extended CCI. We did not observe an effect of BCS or ambient temperature on CCI. The incidence of ARTD in the current study was consistent with clinical endometritis (considered a major source of ARTD) reported in other studies. In contrast—and despite regular veterinary assessment and treatment of on the farms in this study—ARTD extended CCI. Evaluation of the economic impact of ARTD on dairy farms in this region is warranted, and methods to identify high risk cows and develop effective interventions are required.

Physical Traits of Vaginal Mucus Discharge and Their Relations to Conception Rate of Egyptain Baladi Cows

“…Lopez-Gaius et al (1993) stated that color of cervical mucus is considered one of the important factors which affects on sperm penetration and conception however, turbid mucus arrested sperm motility in cows. Hay et al (2019) showed that abnormal cervical mucus discharge associated with significantly decreased in the pregnancy rate in cows. Murugavel and López-Gatius (2009) reported that cervical mucus appearance indicated good sexual health and associated with a higher conception rate in cows.…”

“…Several authors suggested a high association between color of vaginal mucus and conception rate in cows (Lim et al, 2014, Bhat et al, 2015and Parikh et al, 2018. Recently Hay et al (2019) showed that abnormal cervical mucus discharge was associated with significantly decreased pregnancy rate in cows. In addition, Gautam et al (2010) found that cows, which had cloudy vaginal mucus at mating, had lower conception rate compared with other cows.…”

Expression of parlour behaviour, temperament, welfare and approach test in postpartum Surti buffaloes (Bubalus bubalis)

“…Post-partum uterine health is an important factor that influences the fertility and consequently duration of calving interval in dairy animals (Hay et al 2019). Presently, only one animal under the study from primiparous group showed thick white pus discharge with pronounced foul smell.…”

Efecto de la introducción de un proceso del perfeccionamiento en el sistema técnico–organizativo de una unidad lechera

“…Estos resultados se deben a las vacas que están explotación y sobre todo por la alimentación, ya que al establecer áreas de forrajes se pudo mejorar este aspecto. Por otra parte, Ossa et al [19] y Hay et al [20] plantean que el manejo de la alimentación de las hembras es el factor más importante que afecta el intervalo parto-gestación.…”