Effect of High Milk Production on Reproductive Efficiency of Lactating Dairy Cows, Milo Wiltbank

https://www.researchgate.net/publication/266580664_Effect_of_High_Milk_Production_on_Reproductive_Efficiency_of_Lactating_Dairy_Cows 

Article Effect of High Milk Production on Reproductive Efficiency of...

Furthermore, we also found a significantly lower chance of pregnancy in cows yielding more milk than their peers in the herd. Probably, the metabolic stress of producing more milk than cows under the same condition (same management and parity) could interfere with the fertility outcome (Walsh et al., 2007). Moreover, as described by Lucy (2001), in response to genetic selection for milk production, the reproductive physiology of the cow has changed to longer intervals to first ovulation, higher incidence of anestrus, abnormal luteal phases, and greater embryonic loss, resulting in a decline of the reproductive efficiency.

certainly, Increase in milk production in high producing cows has a bad affects on reproduction, especialiy in heat stress situation. of course you can find these effects in many articles.

Hi

I have attached the few articles related to your query, I hope it will be useful for you

Regards

Bharathy

It has somewhat negative feedback on reproductive performance as there will be...

Longer daya open , Days to first ovulation more, lactational anoestrous, longer service period, large calving interval, low calf crop.

Milk production does mainly affect reproductive performance indirectly, in case of insufficient feed intake or inadequate rations, resulting in a negative energy balance, fat mobilization syndrome, decreased immunity, etc..  which usually will impair the cow's fertility through puerperal infections, delayed cycling, formations of cysts etc.

Usually, these factors are a result of insufficient or wrong management in the dry cow period, starting phase, and rations that are not individually adapted to the milk production levels.

Some herds with average 305-day milk productions above 13500 kg. per cow report less fertility problems than other herds averaging 7000 kg.

One direct effect in high yielding cows is that more active liver enzymes will reduce the blood levels of sexual hormones through faster metabolization, which can impair fertility.

I think you for your participation 

There is a lot of discussion in this topic, Lucy, 2001, published a paper indicating the pointed the negative effect of high milking cows and fertility traits. Also there are several papers that reported a negative correlation between milk production and fertility. And fertility traits have been included in genetic programs all over the world. However, It is important to distinguished the difference between milk production at herd level and cow level. Its not the same and the interaction with fertility traits could be really different. The problem needs a more comprehensive assessment that draws expertise from multiple disciplines.

thanx for the answer

@Hugo Toledo-Alvarado

I fully agree with you. Unfortunately, most fertility indexes calculated by geneticists seem to assume that differences in fertility within a herd, although due to different  nutritional requirements for different production levels, are due to genetic factors, which, in an index calculation based on phenotypes only as it was in pre-genomic times, does not pose a real problem as it could be attributed to genome-environmental interactions on the herd level. Things become however totally different when one  starts drawing conclusions on the genome level from factors resulting from individual management errors (not to mention epistatic and epigenetic effects).

However, the consensus among geneticists seems to go towards ignoring these factors, despite the increased focus on and accounting of female genotypes.

thank you Mr Adrian

Attached there is a paper that could help to your question.

Greetings, Hugo

Article Fertility traits of Holstein, Brown Swiss, Simmental, and Al...

thanks a lot M. Hugo for your answer

This is a paper we published several years ago, but it has a lot of data. Basically, if cows are healthy and fed well, there  is not much effect of high production. 

thanks verry much m. J.H. Britt for your answer

This link of artical is useful

Article Herd fertility parameters in relation to milk production in ...

Thans for your answer Khalid, i'm very grateful