Effects of dry-off or continuous lactation in Alpine and Saanen dairy goats carrying single or double kids on peripartum metabolic profile, performances, and milk composition

Abstract

Dairy goat’s lactation persistence forces farmers at limiting nutrient supply to reduce yield at dry-off. Omitting dry period could be a solution, but metabolic effects of this practice have never been tested. Eight Alpine (AL) and 12 Saanen (SA) goats approaching their second kidding blocked by breed and number of kids carried (single - SIN - or double - DOU) were allocated to one out of two groups (4 AL and 6 SA; 5 SIN and 5 DOU in each group). At −42 ± 7 days from kidding (DFK), they were either dried off (DR) or milked continuously until kidding (CL). Body condition score (BCS) was assessed, and blood samples were collected at −10, −3, 5, 12, and 29 DFK to determine metabolic profile. Milk yield and composition were assessed at −56, 7, 31, 62, and 97 DFK. Compared with DR, CL had higher plasma reactive oxygen metabolites and liver enzymes. Compared with DR counterparts, AL-CL had higher nonesterified fatty acids (NEFA) at −10, whereas SA-CL had lower NEFA at −3 DFK. CL goats had lower BCS, higher plasma beta-hydroxybutyrate (BHB) and urea before kidding, but higher glucose at −3 and 5, lower NEFA at 5 and 12, and higher BCS at 29 DFK. CL goats had lower haptoglobin and myeloperoxidase at −3 and 5 DFK, paired with higher albumin, cholesterol, and paraoxonase at 12 DFK. Omitting dry period mitigated the inflammatory condition around kidding in dairy goats, possibly accounting for an improved energy balance in early lactation, despite body reserve mobilisation prepartum was greater under continuous lactation.

HIGHLIGHTS

• Omitting dry period accrued prepartum energy deficit in dairy goats but improved their postpartum energy balance.

• Omitting dry period mitigated acute phase response and inflammation in dairy goats during the late gestation and early lactation phases.

• Omitting dry period in high-yielding goats could allow for a smoother transition to the new lactation coping with the limitations hindering the dry-off procedures.

Keywords:

• Dairy goats
• acute phase response
• inflammation
• energy metabolism
• dry-off

Acknowledgements

Heartfelt thanks to Emanuele Marta, who allowed this research, and Dr. Fabio Bencetti for the precious contribution provided during conceptualization and sample collection.

Ethical approval

This study complied with Italian laws on animal experimentation and ethics (DL n. 116, 27/01/1992) and all the experimental procedures were performed under the supervision of a veterinary practitioner.

Disclosure statement

The authors declare that there is no conflict of interest associated with the paper. The authors alone are responsible for the content and writing of this article.

Data availability statement

The data that support the findings of this study are available from the corresponding author upon reasonable request.

Additional information

Funding

This work was conducted in the framework of projects supported by CREI (Romeo and Enrica Invernizzi Research Centre of the Università Cattolica del S. Cuore) funded by the ‘Fondazione Romeo ed Enrica Invernizzi’, Milan, Italy.