The establishment and maintenance of pregnancy in lactating dairy cows is a complex biological event that is influenced by a multitude of factors, from the reproductive biology of the cow to managerial aspects of the dairy farm. It is often mentioned in the scientific literature that fertility in dairy cows has declined concurrent with major advances in milk production. Some of this decline is ...

The study was conducted to know the effect of flushed feeding on estrus synchronization and conception rate of Holstein ÍLocal crossbred cow’s after using the GnRH (fertagyl) and PGF2α hormone. As a representative sample 20 Holstein ÍLocal crossbred cows were chosen from Chittagong Cantonment Military Dairy Farm in Bangladesh and the experimental work was carried out for 60 days. Ten cows were ...

The objective of this study was to compare the effectiveness of the Ovsynch and controlled internal drug releasing (CIDR) protocols under commercial conditions for the treatment of cystic ovarian disease in dairy cattle. A total of 401 lactating dairy cows with ovarian cysts were alternatively allocated to two treatment groups on the day of diagnosis. Cows in the Ovsynch group were treated with...

Uterine infection is one of the reproductive diseases that can have disturbing postpartum uterine health in cattle. Therefore, identification of resistant genotypes to uterine infection is important. Lactoferrin (LF) is one of the major antimicrobial compounds in the normal uterine discharges of cows. We hypothesized that allelic diversity in LF gene may contribute to susceptibility or resistan...

Our objective was to assess the effects of feeding negative dietary cation-anion difference (DCAD) prepartum diets on milk production, reproductive performance, and culling. Cows from 4 commercial farms in Ontario, Canada were enrolled a pen-level controlled trial November 2017 April 2019. Close-up pens (1 per farm) with cows 3 wk before calving randomly assigned DCAD (TRT; ?108 mEq/kg dry matt...

in order to examine the effect of using rumen protected methionine (mepron, evonik industries, hanau, germany) on productive and reproductive performance under field condition, 195 holstein cows were used in a unbalanced completely randomized design and 2 groups. experimental treatments consisted of: 1) control group with 110 holstein dairy cows (71±51 dim and 47.5±12 milk yield) and without me...

The objectives of the present study were to determine the effects of resynchronization with GnRH on Day 21 after artificial insemination (AI) on pregnancy rate and losses of pregnancy in lactating dairy cows. Holstein cows (n=585) on two dairy farms were assigned to one of two treatments in a randomized complete block design. On Day 21 after a pre-enrollment AI, animals assigned to the resynchr...

The dairy industry in North America has changed dramatically with a trend in direction of larger herds and higher production per cow, which seems to be associated with a decrease in fertility, especially a decrease in conception rates and extension of calving intervals (Butler, 2000; Lucy, 2001; Stevenson, 2001) This decline in fertility of lactating dairy cows is observed not only in North Ame...

One strategy for improving fertility in cattle is mid-cycle administration of GnRH to increase progesterone secretion and delay luteolysis. This strategy might be especially useful during hot weather because heat stress increases uterine prostaglandin release and reduces development of the elongating embryo. A series of experiments was conducted to test the efficacy of GnRH for increasing ferti...