title: Lactation curve and milk quality of goats experimentally infected with Trypanosoma vivax.
abstract: The present study aimed to evaluate the effects of Trypanosoma vivax infection on the shape of the lactation curve and the milk quality of dairy goats experimentally infected with T. vivax. In total, twenty Saanen goats, aged 26-30 months and the same number of calving (two calvings), were divided into two experimental groups: an infected group, consisting of ten goats intravenously infected with 0.5 ml of blood containing approximately 1.25 × 10(5) trypomastigotes of T. vivax and ten uninfected animals as the control group. Clinical tests and hematocrit, parasitemia, and serum biochemistry evaluations were performed on all of the goats. Milk production was measured daily for 152 days by hand milking the goats and weighing the milk. Every seven days, physiochemical analyses were performed to evaluate the milk. Wood's nonlinear model was used to analyze the lactation curve parameters. The infected goats had high levels of parasitemia and hyperthermia, significantly reduced hematocrit, serum total protein, albumin, and glucose levels and increased cholesterol and urea concentrations. Wood's model indicated that the milk production of goats in the infected group declined sharply over a short period of time and produced a flattened yield curve and significant difference (P < 0.05) in the rate of increase of peak milk production, rate of decrease of milk production after the peak, day of peak milk production, and maximum peak milk production compared with that of the control group. Trypanosomiasis also affected the persistency of lactation, which was significantly reduced in goats in the infected group. In addition, the physico-chemical properties of the milk, including the fat content, defatted dry extracts (DDE) and protein content, decreased significantly (P < 0.05) in the goats in the infected group compared with those in the control group. The T. vivax-infected goats showed reduction in milk production, persistence of lactation, and fat levels, the defatted dry extract (DDE) content, and protein, changing the quality of milk.
authors.affiliation: Department of Animal Sciences, Federal Rural University of the Semiarid, Av. Francisco Mota, Br 110, Km 47, Costa e Silva, 5959625-900, Mossoró, RN, Brazil. Electronic address: fcoclopes@bol.com.br.
authors.forename: Francisco Canindé
authors.initials: FC
authors.lastname: Lopes
authors.affiliation: Department of Animal Sciences, Federal Rural University of the Semiarid, Av. Francisco Mota, Br 110, Km 47, Costa e Silva, 5959625-900, Mossoró, RN, Brazil. Electronic address: kalianepaiva@yahoo.com.br.
authors.forename: Kaliane Alessandra Rodrigues
authors.initials: KA
authors.lastname: de Paiva
authors.affiliation: Department of Animal Sciences, Federal Rural University of the Semiarid, Av. Francisco Mota, Br 110, Km 47, Costa e Silva, 5959625-900, Mossoró, RN, Brazil. Electronic address: wesleyadson@outlook.com.
authors.forename: Wesley Adson Costa
authors.initials: WA
authors.lastname: Coelho
authors.affiliation: Department of Animal Sciences, Federal Rural University of the Semiarid, Av. Francisco Mota, Br 110, Km 47, Costa e Silva, 5959625-900, Mossoró, RN, Brazil. Electronic address: vitor_farmacia@hotmail.com.
authors.forename: Francisco Vítor Aires
authors.initials: FV
authors.lastname: Nunes
authors.affiliation: Department of Animal Sciences, Federal Rural University of the Semiarid, Av. Francisco Mota, Br 110, Km 47, Costa e Silva, 5959625-900, Mossoró, RN, Brazil. Electronic address: jardelbezerra@bol.com.br.
authors.forename: Jardel Bezerra
authors.initials: JB
authors.lastname: da Silva
authors.affiliation: Department of Animal Sciences, Federal Rural University of the Semiarid, Av. Francisco Mota, Br 110, Km 47, Costa e Silva, 5959625-900, Mossoró, RN, Brazil. Electronic address: carolmendesvet@hotmail.com.
authors.forename: Carolina
authors.initials: C
authors.lastname: de Gouveia Mendes da Escóssia Pinheiro
authors.affiliation: Department of Zootecnia, Federal University of the Piauí, Campus Professora Cinobelina Elvas, Br 135 Km 03, Planalto Horizonte, 64900-000, Bom Jesus, PI, Brazil. Electronic address: layannepraca@yahoo.com.br.
authors.forename: Layanne
authors.initials: L
authors.lastname: de Macêdo Praça
authors.affiliation: Department of Animal Sciences, Federal Rural University of the Semiarid, Av. Francisco Mota, Br 110, Km 47, Costa e Silva, 5959625-900, Mossoró, RN, Brazil. Electronic address: jeanberg@ufersa.edu.br.
authors.forename: Jean Berg Alves
authors.initials: JB
authors.lastname: Silva
authors.affiliation: Department of Animal Sciences, Federal Rural University of the Semiarid, Av. Francisco Mota, Br 110, Km 47, Costa e Silva, 5959625-900, Mossoró, RN, Brazil. Electronic address: iberefreitas@bol.com.br.
authors.forename: Carlos Iberê
authors.initials: CI
authors.lastname: Alves Freitas
authors.affiliation: Department of Animal Sciences, Federal Rural University of the Semiarid, Av. Francisco Mota, Br 110, Km 47, Costa e Silva, 5959625-900, Mossoró, RN, Brazil. Electronic address: jaelsoares@hotmail.com.
authors.forename: Jael Soares
authors.initials: JS
authors.lastname: Batista
mesh_terms: D000821:Animal Feed; D000818:Animals; D001774:Blood Chemical Analysis / Q000662:veterinary; D001798:Blood Proteins / Q000378:metabolism; D001831:Body Temperature; D002784:Cholesterol / Q000097:blood; D004435:Eating; D005260:Female; D015511:Goat Diseases / Q000469:parasitology / Q000503:physiopathology*; D006041:Goats; D006400:Hematocrit / Q000662:veterinary; D007775:Lactation Disorders / Q000469:parasitology / Q000662:veterinary*; D008892:Milk / Q000737:chemistry / Q000592:standards*; D018512:Parasitemia / Q000662:veterinary; D011897:Random Allocation; D016689:Trypanosoma vivax; D014353:Trypanosomiasis, African / Q000503:physiopathology / Q000662:veterinary*; D014508:Urea / Q000097:blood
chemical_list: D001798:Blood Proteins; D014508:Urea; D002784:Cholesterol
keywords: Dairy goats; Lactation curve; Milk composition; Trypanosomiasis