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Gastrointestinal parasites presence during the peripartum decreases total milk production in grazing dairy Holstein cows
- Source :
- Veterinary Parasitology. 178:311-318
- Publication Year :
- 2011
- Publisher :
- Elsevier BV, 2011.
-
Abstract
- Parasitism in cattle is known to impair growth and development. Recent findings suggest that productivity of adult animals is also affected, but little is known about the physiological mechanisms involved. Furthermore, development of nematode resistance to drugs makes imperative the search of management practices that avoid whole herd treatment. We undertook an epidemiological and endocrine study in a grass based dairy farm in Argentina to study the effect of parasites on milk production and the underlying mechanisms involved, and identify individual animals that would benefit from antiparasitic treatment. All the cows in the dairy were followed monthly for egg parasite output in feces. Samples were cultured for genera determination. Milk production and reproductive results were recorded and periodical bleedings for hormone determination were performed. Nematode egg output (EPG) was maximal in late Summer and Autumn and minimal in Spring in coincidence with the Ostertagia inhibition-disinhibition cycle as this genus had the highest prevalence in all the study. The highest proportion of positive samples was found in the high producing herd and maximal counts were found in the peripartal period. Milk production did not correlate with EPG mean values but, when cows were grouped by EPG positivity around parturition, a significant difference in total milk production between EPG null and positive cows was observed. Positive cows produced 7%, 12% or 15% less milk than null EPG cows, depending on the sampling month/s chosen for classification. The highest difference was seen when both prepartum and postpartum samples were taken into account. No difference in lactation length and a marginal effect on partum to first service interval were encountered. Endocrine studies revealed a decrease in serum growth hormone (GH), type I insulin-like growth factor (IGF-I) and prolactin during lactation in cows with positive EPG in the first postpartum sample with respect to null EPG cows at that time. GH levels decreased and prolactin and IGF-I levels increased in both groups of cows from month 0 to 6 in milk. Serum insulin levels remained stable throughout lactation and were similar in both groups of cows. In conclusion, EPG around parturition may be a useful tool for identifying cows that will have a decrease in productivity due to parasite effects and would possibly benefit from an antiparasitic treatment. Besides, our results suggest that detrimental effect of parasites on milk production may be mediated by GH, IGF-I and prolactin serum levels.
- Subjects :
- medicine.medical_specialty
Nematoda
Gastrointestinal Diseases
Argentina
Cattle Diseases
Biology
Feces
Animal science
Internal medicine
Lactation
Peripartum Period
medicine
Parasite Egg Count
Animals
Insulin
Endocrine system
Insulin-Like Growth Factor I
Nematode Infections
Chi-Square Distribution
General Veterinary
food and beverages
General Medicine
Prolactin
Milk
Endocrinology
medicine.anatomical_structure
Growth Hormone
Herd
Cattle
Female
Parasitology
Seasons
Hormone
Subjects
Details
- ISSN :
- 03044017
- Volume :
- 178
- Database :
- OpenAIRE
- Journal :
- Veterinary Parasitology
- Accession number :
- edsair.doi.dedup.....acf4bd5a501f60a2db03cc150fcb8758
- Full Text :
- https://doi.org/10.1016/j.vetpar.2010.12.045