Pregnancy loss in dairy cows: the contributing factors, the effects on reproductive performance and the economic impact

Abstract

This study investigated the effects of the herd, cow parity, the insemination protocol and season on the incidence of pregnancy loss (PL) in dairy herds. Furthermore, we determined the downstream effects of PL on reproductive performance and its economic impact. The overall incidence rate of PL was 6.9% in 1,001 pregnant cows and its incidence peaked (p < 0.01) during the second trimester of gestation. GLIMMIX analysis revealed that cow parity was the important risk factor for the PL. The odds ratio showed that the likelihood of PL in cows with parities of 1 or 2 was decreased by 0.6 or 0.5 fold compared to the cows with a parity of 3 or higher. Following PL, the mean rate of endometritis was 23.2% and endometritis was more common (p < 0.05) when PL occurred during the third trimester than during the first and second trimesters. The mean culling rate was 46.4% and this did not differ with the period of PL. The overall mean intervals from PL to the first service and conception were 63.4 and 101.8 days, respectively. The mean interval from PL to first service was longer (p < 0.01) for cows with PL during the third trimester than for the cows with PL during the first and second trimesters. The economic loss resulting from each PL was estimated at approximately $2,333, and this was largely due to an extended calving interval and increased culling. These results suggest that cow parity affects the incidence of PL, which extends calving interval and causes severe economic loss of dairy herds.

Review of common causes of abortion in dairy cattle in Ethiopia

“…These include heat stress, season, milk production, cow parity, serum progesterone level after conception, the inseminating bull, twin pregnancy and the herd (Lee and Kim, 2007). However, other investigations have reported that milk production and cow parity were not associated with abortion (Moore et al, 2005).…”

“…The most important genetic disorders include chromosomal and single gene disorders and these disorders result in high abortion rate in cows and increased calf sterility. Cow parity, sire effect, age at conception and abortion history could be some of the non-infectious maternal and paternal factors that cause abortion (Thurmond et al, 2005;Lee and Kim, 2007).…”

Associations of reproduction and health with the performance and profit of dairy cows

“…As pointed out by LeBlanc (2010), it is important to separate the biology of the reproductive function from the effects of the economically based management decisions about culling and continued breeding. According to Lee and Kim (2007) and Leroy and Kruif (2006), the improved estrous detection could reduce the number of cows that are removed from the herd for reproductive reasons. A good herd management can achieve lower culling rates for the reasons of fertility.…”

“…Farmers may be unaware of the cost that is associated with reproductive culling although the level of reproductive performance directly affects the economic performance of a dairy herd (Lee and Kim 2007;Giordano et al 2012). The lowest reported profitability of costs was seen in the groups of the longest CI group (−15.22 ± 4.26%; P < 0.05), the highest LF group (−14.08 ± 4.25%; difference nonsignificant), and the highest PC group (−16.08 ± 4.33%; P < 0.05).…”

Molecular detection of Bluetongue Virus (BTV) and Bovine Leukemia Virus (BLV) in uterine biopsies of dairy cows with or without reproductive problems

“…Delivery sets the beginning of a new lactation and the birth of heifers that allow for herd reposition (SANTOS et al, 2004). Each gestational loss in a dairy farm causes an estimated financial damage of $2.333 (LEE; KIM, 2007). Reproductive loss is linked to several factors, including endocrine, genetic, metabolic or infectious alterations (DISKIN;MORRIS, 2008;WALSH et al, 2011).…”