Format

Send to

Choose Destination
Res Vet Sci. 2017 Oct;114:511-517. doi: 10.1016/j.rvsc.2017.09.027. Epub 2017 Sep 28.

Study of the association of atmospheric temperature and relative humidity with bulk tank milk somatic cell count in dairy herds using Generalized additive mixed models.

Author information

1
Università degli Studi di Milano, Dipartimento di Scienze Veterinarie per la Salute, la Produzione Animale e la Sicurezza Alimentare, via Celoria 10, 20133 Milan, Italy.
2
Università degli Studi di Milano, Department of Clinical Sciences and Community Health, Via Vanzetti 5, 20133 Milan, Italy.
3
Università degli Studi di Milano, Dipartimento di Medicina Veterinaria, via Celoria 10, 20133 Milan, Italy.
4
Università degli Studi di Milano, Department of Clinical Sciences and Community Health, Via Vanzetti 5, 20133 Milan, Italy; Unit of Medical Statistics and Biometry, Fondazione IRCCS Istituto Nazionale dei Tumori, Via Venezian 1, 20133 Milan, Italy.
5
Università degli Studi di Milano, Dipartimento di Medicina Veterinaria, via Celoria 10, 20133 Milan, Italy; Animal Health Diagnostic Center, Quality Milk Production Services, Cornell University, 240 Farrier Road, Ithaca, NY 14853, USA. Electronic address: paolo.moroni@unimi.it.

Abstract

Elevated bulk tank milk somatic cell count (BMSCC) has a negative impact on milk production, milk quality, and animal health. Seasonal increases in herd level somatic cell count (SCC) are commonly associated with elevated environmental temperature and humidity. The Temperature Humidity Index (THI) has been developed to measure general environmental stress in dairy cattle; however, additional work is needed to determine a specific effect of the heat stress index on herd-level SCC. Generalized Additive Model methods were used for a flexible exploration of the relationships between daily temperature, relative humidity, and bulk milk somatic cell count. The data consist of BMSCC and meteorological recordings collected between March 2009 and October 2011 of 10 dairy farms. The results indicate that, an average increase of 0.16% of BMSCC is expected for an increase of 1°C degree of temperature. A complex relationship was found for relative humidity. For example, increase of 0.099%, 0.037% and 0.020% are expected in correspondence to an increase of relative humidity from 50% to 51%, 80% to 81%; and 90% to 91%, respectively. Using this model, it will be possible to provide evidence-based advice to dairy farmers for the use of THI control charts created on the basis of our statistical model.

KEYWORDS:

Bovine; Generalized Additive Models; Somatic cell count; Temperature Humidity Index

PMID:
28987958
DOI:
10.1016/j.rvsc.2017.09.027
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center