In Peru, the payment received by the producer per kilogram of raw milk is based on a base price, to which bonuses are applied according to quality criteria established by the dairy industry. In the present study, the relationship of compositional and hygienic quality with the value of payment per kilogram of milk in a dairy in the Huaura Valley was evaluated. Retrospective information on the total solids content (%ST), mesophilic aerobic count (UFC/ml) and the payment received (Peruvian sol - S/) per kilogram of raw milk (VP) was obtained from biweekly reports for the period 2017-2020. Data were analysed using Spearman’s trend and correlation analysis. The results showed a positive trend for the %ST (from 12.02% in 2017 to 12.21% in 2020) and negative for the CFU/ml (32,690 in 2017 to 18,117 in 2020). The PV had a similar trend to the %ST (S/ 1.39 in 2017 to S/ 1.41 in 2020). The %ST a...

            The aim of the research was to study the association between the presentation of endometritis and serum calcium levels in intensively reared dairy cows from Lima, Peru. The study was carried out with 76 Holstein cows. Blood samples were taken on the seventh day of parturition to measure calcium levels using a spectrophotometer, considering 8 mg/dl as the threshold to determine the presence of subclinical hypocalcemia. The diagnosis of endometritis was made at 35 ± 3 days postpartum using the commercial Metricheck® device to evaluate the appearance of vaginal fundus discharge, considering as endometritis a score greater than or equal to 2 on the McDougall scale. A significant difference was found between multiparous cows with and without hypocalcemia in the presentation of endometritis (p<0.02), showing 1.65 times mor...

            The aim of the research was to study the association between the presentation of endometritis and serum calcium levels in intensively reared dairy cows from Lima, Peru. The study was carried out with 76 Holstein cows. Blood samples were taken on the seventh day of parturition to measure calcium levels using a spectrophotometer, considering 8 mg/dl as the threshold to determine the presence of subclinical hypocalcemia. The diagnosis of endometritis was made at 35 ± 3 days postpartum using the commercial Metricheck® device to evaluate the appearance of vaginal fundus discharge, considering as endometritis a score greater than or equal to 2 on the McDougall scale. A significant difference was found between multiparous cows with and without hypocalcemia in the presentation of endometritis (p<0.02), showing 1.65 times mor...

The aim of this research was to model the lactation curve in dairy cows with nonlinear models (MNL) and nonlinear mixed models (NLMM), in an intensive breeding dairy farm during the period 2007-2013. In total, 22 173 data referred to biweekly milk production controls were analysed, corresponding to 1302 lactations and 668 Holstein cows. The Brody, Wood, Cobby and Wilmink mathematic models were used evaluating NLM and NLMM, considering the cow as a random effect using SAS v. 9.4 statistical package. Applying information from Akaike (AIC) and Bayesian (BIC) method, NLMM was found to be the best fit for the 305-day lactation curve. Wood mixed model was the best fit for the first calving and Wilmink mixed model for the other calvings. Likewise, production peak, days to production peak, percent productive yield by thirds during the lactation period and production at 305 days according to...

The aim of this research was to model the lactation curve in dairy cows with nonlinear models (MNL) and nonlinear mixed models (NLMM), in an intensive breeding dairy farm during the period 2007-2013. In total, 22 173 data referred to biweekly milk production controls were analysed, corresponding to 1302 lactations and 668 Holstein cows. The Brody, Wood, Cobby and Wilmink mathematic models were used evaluating NLM and NLMM, considering the cow as a random effect using SAS v. 9.4 statistical package. Applying information from Akaike (AIC) and Bayesian (BIC) method, NLMM was found to be the best fit for the 305-day lactation curve. Wood mixed model was the best fit for the first calving and Wilmink mixed model for the other calvings. Likewise, production peak, days to production peak, percent productive yield by thirds during the lactation period and production at 305 days according to...

The objective of the study was to evaluate two methods of detection of oestrus in two seasons and their influence on reproductive efficiency in Holstein cows. A total of 1445 records was evaluated from an intensive commercial farm located in the north of Lima, Peru in 2014. The methods of detection of oestrus were a commercial activity meter (T1), visual observation (T2) and the combination of both methods (T3). The reproductive parameters evaluated were the rate of heat detection,  conception rate, number of services per conception, open days and parity number. The highest number of heats was detected with T3 (52.2%) compared to 27.5% of T1 and 20.2% of T2 (p<0.05). T1 was more efficient in detecting heats during the summer (34.7% heats) compared to T2 (13.2%) (p<0.05). T1 showed a higher number of heats in the first and second lactations (30.3 and 26.5%, respectively) compared t...

El objetivo del estudio fue evaluar dos métodos de detección del celo en dos épocas del año y su influencia sobre la eficiencia reproductiva de vacas Holstein. Se evaluaron 1445 registros de un establo comercial de explotación intensiva ubicada en el norte de Lima, Perú en 2014. Los métodos de detección de celo fueron un medidor de actividad comercial (T1), la observación visual (T2) y la combinación de ambos métodos (T3). Los parámetros reproductivos evaluados fueron la tasa de detección de celos, la tasa de concepción, el número de servicios por concepción, los días abiertos y el número de parto. El mayor número de celos fue detectado con T3 (52.2%) en comparación al 27.5% de T1 y al 20.2% de T2 (p<0.05). T1 fue más eficiente en la detección de celos durante el verano (34.7% de celos) en comparación con T2 (13.2%) (p<0.05). T1 detectó mayor número de celo...

The study aimed to determine the effect of body condition score (SCC) at the time of artificial insemination on the conception rate (TC) of Holstein cows raised under an intensive system. In total, 1851 inseminations from dairy farm in Lima, Peru were evaluated. The SCC was evaluated through visual observation on a 1-5 scale, forming two groups: SCC <3 and SCC ≥3. The pregnancy diagnosis was made between days 35 and 42 post-service. Overall TC (GTC) and at first insemination were significantly higher in cows with SCC ≥3 than in cows with SCC <3 (p<0.01), with no significant differences at the second and third insemination. SCC had a significant effect on TC at first insemination in multiparous cows (p<0.05), but not in primiparous cows. The SCC did not have a significant effect on the GTC or at the first insemination in cows bred in times of heat stress (October-June), wh...