Milton Maturana Filho

Productive performance and composition of milk protein fraction in dairy cows supplemented with fat sources.

The objective of this study was to evaluate the use of fat sources in rations for lactating cows on the productive performance and composition of milk protein fraction. Twelve Holstein cows were used, grouped in three balanced 4 × 4 Latin squares, fed with the following rations: control; refined soybean oil; whole raw soybean; and calcium salts of unsaturated fatty acid (Megalac-E). Dry matter and nutrient intake, and daily milk production were evaluated. The samples used to analyze milk composition were collected in two alternate days and were obtained from two daily milking. Milk composition and total nitrogen, non-protein nitrogen and non-casein nitrogen ratios were analyzed. The casein, serum protein and true protein ratios were obtained by difference. Dry matter and nutrient intakes were lower when cows received the diet containing calcium salts of fatty acids, in relation to the control diet. Among the diets with fat sources, the one with whole raw soybean and calcium salts decreased milk production. There was no effect of fat sources added to the diet on crude protein, non-protein nitrogen, non-casein nitrogen, true protein, casein, casein/milk true protein ratio and serum protein. Similarly, the experimental diets did not influence the protein fractions when expressed in percentage of milk crude protein. The utilization of fat sources in diets changes milk production and composition of lactating cows, but does not influence the composition of milk protein fractions.

Parâmetros sanguíneos de vacas leiteiras suplementadas com diferentes fontes de gordura

This study was carried out to evaluate the use of different fat sources in dairy cows rations and its effects on dry matter intake, milk yield and composition, and blood parameter. Twelve Holstein cows were allocated in three balanced latin square 4x4, and fed with the following rations: 1) Control, with 2.5%; 2) Refined soybean oil; 3) Whole soybean; and 4), Calcium salts of fatty acids (Megalac-E). The concentrations of total cholesterol and lipoprotein low density (LDL) were higher (P<0.05) for cows that received rations with fat sources, which also causes increased (P<0.05) e concentration of high density lipoprotein (HDL). The concentrations of urea and blood urea nitrogen were similar among the rations, except for the diet containing calcium salts of fatty acids, which showed lower (P<0.05). The dry matter intake was lower (P<0.05) in cows that received calcium salts in the rations. The animals that received a diet containing whole soybeans as a source of fat had lower (P<0.05) yield milk when compared to other rations used. The use of fat sources in dairy cows rations influenced the blood parameters, especially for parameters related to lipidogram.

Supplementation with sunflower seed increases circulating cholesterol concentrations and potentially impacts on the pregnancy rates in Bos indicus beef cattle

We aimed to evaluate the effect of supplementation with sunflower seed on blood concentrations of progesterone and cholesterol and on the pregnancy rate in beef cattle subjected to timed artificial insemination (TAI) and timed embryo transfer (TET). In experiment 1, cows were received 22-day supplements containing (sunflower, n = 66) sunflower seed or not (control, n = 67) immediately after a progesterone/estradiol-based TAI protocol (Day 0). The cholesterol concentration on Day 21 and the pregnancy rate were greater (P < 0.03) in the sunflower group (148.2 ± 6.1 mg/dL and 66.7%) than those in the control group (116.0 ± 6.4 mg/dL and 47.8%). In experiment 2, heifers received an in vitro-produced embryo 7 days after the expected time of the synchronized ovulation. Heifers were separated into two supplementation groups (sunflower, n = 106 and control, n = 111) for 22 days. The plasma progesterone concentration on Day 7 was not different between the groups. However, on Day 19, the plasma progesterone concentration was greater (P < 0.0001) in the sunflower group (5.8 ± 0.4 ng/mL) than that in the control group (3.5 ± 0.4 ng/mL). A greater (P < 0.05) cholesterol concentration was observed in the sunflower group than that in the control group on Days 7 (306.0 ± 11.6 vs. 277.1 ± 11.9 mg/dL, respectively) and 19 (260.5 ± 8.0 vs. 232.0 ± 8.0 mg/dL, respectively). The pregnancy rate was greater (P = 0.01) in the sunflower-treated heifers (55.7%) than that in control-treated heifers (36.9%). Results indicate that sunflower seed supplementation increases the circulating cholesterol concentrations and potentially impacts the pregnancy rate in suckled beef cattle subjected to TAI or TET.

Fertility and uterine hemodynamic in cows after artificial insemination with semen assessed by fluorescent probes

Fluorescent probes (propidium iodide, Hoechst 33342, fluorescein isothiocyanate-conjugated Pisum sativum agglutinin, and 5,5,6,6-tetrachloro-1,1,3,3-tetraethylbenzimidazolcarbocyanine iodide) were used to simultaneously evaluate the integrity of plasma and acrosomal membranes as well as mitochondrial membrane function in cryopreserved bovine semen and to verify its influence on fertility and postinsemination uterine vascularization. One hundred eighty-two Nellore cows were distributed for artificial insemination (AI) using semen batches separated according to the cell percentage presenting intact plasma membrane, intact acrosome, and high mitochondrial function (IPIAH): group G (44.5% IPIAH, n = 68), group M (23.0% IPIAH, n = 56), and group R (8.5% IPIAH, n = 58). The uterine hemodynamic was evaluated by Doppler sonogram in three periods: 30 hours before AI, 4 and 24 hours after AI were considered the resistance index and the uterine vascularization score. The pregnancy rate of group G (64.7%) was greater (P > 0.05) compared with group R (36.2%), but both did not differ from group M (50.0%). There was no effect (P > 0.05) of semen quality on uterine vascularization. Greater vascularization was noticed 4 hours after AI than 30 hours before and 24 hours after AI. Semen evaluation using fluorescent probes contributes to predicting fertilizing potential of semen. The use of semen with less percentage of IPIAH sperm does not alter uterine hemodynamic in cows.

Use of FSH in two different regimens for ovarian superstimulation prior to ovum pick up and in vitro embryo production in Holstein cows

We aimed with the present study to evaluate the effects of FSH treatment (200xa0mg) split in four or six administrations on ovarian follicle stimulation and inxa0vitro oocyte competence for embryo production in dairy cows with synchronized follicular wave emergence. On random days of the estrous cycle (Day 0), non-lactating Holstein cows received a progesterone (P4)-releasing intravaginal device and 2xa0mg estradiol benzoate IM. On Day 3, they received 0.530xa0mg sodium cloprostenol (PGF2α) IM. Control cows (nxa0=xa035) received no further treatments, whereas FSH-treated cows received 200xa0mg FSH split in four (FSH4 group; nxa0=xa033) or six (FSH6 group; nxa0=xa033) administration regimens. Starting on Day 4, cows in FSH4 group received 200xa0mg FSH split in four equivalent doses of 50xa0mg 12xa0h apart. Cows in FSH6 group received the same total FSH dose split in six equivalent doses of 33.3xa0mg 12xa0h apart, but treatments started on Day 3. On Day 7 AM (36xa0h of coasting period for FSH-treated groups), the P4 devices were removed and cows were subjected to ovum pick up (OPU). Viable oocytes were inxa0vitro fertilized using sexed-sorted semen. Although FSH treatment did not (Pxa0>xa00.1) increase the total number of follicles (Control, 53.2xa0±xa04.5 vs. FSH-treated, 51.4xa0±xa03.1), the two hormonal stimulation regimens, FSH4 and FSH6, increased the number of medium follicles (6-10xa0mm; 5.2xa0±xa00.5 vs. 18.1xa0±xa01.4; Pxa0<xa00.0001) and reduced the number of small follicles (2-5.9xa0mm; 46.3xa0±xa05.1 vs. 31.0xa0±xa02.4 Pxa0<xa00.0001). Also, FSH treatment or regimen did not increase (Pxa0>xa00.1) the number of viable oocytes (Control, 12.6xa0±xa01.26 vs. FSH-treated, 12.70xa0±xa01.03), recovery rate (Control, 36.5% vs. FSH-treated, 36%) and the number of inxa0vitro produced blastocyst (Control, 4.1xa0±xa00.52 vs. FSH-treated 4.3xa0±xa00.5). We concluded that FSH stimulation protocol proposed herein is effective to stimulate the growth of small antral follicle population prior to OPU, but it was ineffective to improve inxa0vitro oocyte competence for embryo production in non-lactating Holstein cows with synchronized follicular wave emergence.

Effect of unsaturated fatty acid supplementation on digestion, metabolism and nutrient balance in dairy cows during the transition period and early lactation

The objective of this study was to evaluate the influence of unsaturated fatty acids in diets for dairy cows during the transition period and early lactation on intake, digestion and nutrient balance. Thirty-six multiparous and pregnant Holstein cows were randomly distributed to receive one of the experimental diets in the period from 35 days before the expected date of parturition to 84 days post-partum. Diets were fed as a total mixed ration and were as follows: control (C); soybean oil (SO), based on inclusion of 30 g/kg (DM basis); and calcium salts of unsaturated fatty acids (CS), based on inclusion of 30 g/kg (DM basis). Pre-partum dry matter intakes (DMI) of cows fed C, SO and CS were 11.9, 9.5 and 9.6 kg/d, respectively. Post-partum DMI was affected by experimental diets (18.5, 15.0 and 17.4 kg/d for C, SO and CS, respectively). The energy balance in the transition period of animals fed CS was 4.41 Mcal/d higher than cows fed SO and 1.3 Mcal/d higher than cows fed C. Supplementing cows with unsaturated fatty acid sources is a strategy for dairy cows in the transition period.

Uterine lavage is efficient to recover endometrial cytology sample and does not interfere with fertility rate after artificial insemination in cows.

Productivity rates directly depend on the fertility of a herd, which in turn can be influenced by many factors. Semen deposited in the female reproductive tract is foreign to the body and, in response to this invasion, produces an inflammatory reaction, which is characterized by rapid infusion of polymorphonuclear (PMN) cells. Techniques to obtain an endometrial sample are usually invasive and can mask the true inflammatory response. Ultrasound is a noninvasive technique and can contribute to the diagnosis of postartificial insemination (AI) inflammatory response in cattle. The present study was divided into two experiments. The aim of experiment 1 was to compare two methods of endometrial cytology collection, uterine cytobrush (UC) and uterine lavage (UL), and their effects on uterine hemodynamics that provide information about blood flow. The two methods were evaluated by Doppler ultrasound using the spectral and color modes. For that purpose, 19 Nellore cows were synchronized for timed AI and subjected to UC (nxa0=xa09) or UL (nxa0=xa010). The techniques were performed 4xa0hours after AI. The results showed that both techniques allow collection of a good quality sample and with enough PMN cells to perform counting. More PMN cells were obtained by UL than UC. There was no difference in uterine blood flow between the UC and UL groups in any of the periods evaluated (34xa0hours before and 4, 24, and 48xa0hours after collection of uterine sample). On the basis of results of experiment 1, the effect of UL on fertility was studied in experiment 2. A total of 128 Nellore cows were synchronized for TAI; 35 cows were subjected to endometrial cytology by UL 4xa0hours after AI, and 93 were not submitted to any procedure (control). Pregnancy diagnosis was performed by transrectal ultrasound 30xa0days after AI. Pregnancy rates did not differ between UL (54.29%) and control (56.99%) groups. The results of this study showed that UL allows the collection of more representative cells of the surface of the uterus than UC technique and causes no damage to the reproductive tract. Moreover, UL did not affect pregnancy rate when performed 4 hours after AI.

Soybean oil and calcium salts of fatty acids as fat sources for Holstein dairy cows in transition period

Objetivou-se com este estudo avaliar os efeitos do uso de diferentes fontes de acido graxo omega 6 na dieta de vacas leiteiras no periodo de transicao e inicio da lactacao sobre o desempenho produtivo e bioquimico em vacas da raca Holandesa. As vacas foram alimentadas com as seguintes dietas: 1) controle, 2) oleo de soja refinado, 3) os sais de calcio de acidos graxos insaturados (Megalac-E). As dietas foram formuladas para atender as exigencias nutricionais das vacas durante o periodo de pre-parto e pos-parto, dentro de cada grupo experimental. As dietas experimentais afetaram o consumo de materia seca, o peso corporal, escore de condicao corporal e equilibrio de energia no periodo pos-parto. As dietas experimentais nao afetaram os parâmetros bioquimicos no soro: glicose, proteina total, albumina, ureia, ureia serica, colesterol total, HDL-colesterol, acidos graxos nao esterificados, β-hidroxibutirato, aspartato aminotransferase, γ-glutamil transferase, fosfatase alcalina, tambem nao sendo observadas diferencas entre os contrastes analisados. As fontes de acido graxo omega 6 nao influenciaram diretamente o bioquimico de vacas leiteiras no periodo de transicao.

Assessment of the usage of biodegradable polymeric matrix in vaginal devices to sustain progesterone release in cows

The usage of timed artificial insemination (TAI) at a low cost leading to better reproductive rates has been the aim of several research groups in the field. Usually during TAI protocols, sustained progesterone (P4 ) release devices are employed. Most devices are constituted of a nylon skeleton covered with a silicon layer with P4 . A device based on biopolymers was developed in order to reduce costs and decrease its environmental impact. In this study, we compared the kinetics of sustained progesterone release among devices manufactured with a polymeric blend made of polyhydroxybutyrate-valerate (PHBV) and poly-ε-caprolactone (PCL) (DISP) which were compared with DIB® (Internal Bovine Device) used as the control. In the in vitro and in vivo progesterone release tests, two types of biopolymer-based devices with a superficial area of 147xa0cm2 were used: DISP8 (46% PHBV, 46% PCL and 8% P4 ; nxa0=xa04), DISP10 (45% PHBV, 45% PCL, 10% P4 ; nxa0=xa04) and DIB® (1xa0g P4 , 120xa0cm2 area; nxa0=xa03). The in vitro tests were carried out according to USP XXIII specifications and were performed in a dissolutor sink using an alcohol/water mixture (60/40xa0v/v) as a release media and samples were collected at 2xa0min, 2, 4, 8, 12, 24, 48, 60, 72, 84 and 96xa0h. P4 concentrations were measured through spectrophotometry in a 244xa0nm long wave. Three to 3 comparisons of angular coefficients of the straight lines obtained by regression analysis of accumulated P4 concentrations as a function of square root of time were carried out. Furthermore, the diffusion coefficient values of P4 were also determined for DISP8 and DISP10. The results showed that the concentrations of P4 were higher in the DISP10 (774.63xa0±xa045.26xa0μg/cm2 /t1/2 ) compared to DISP8 (566.17xa0±xa03.68xa0μg/cm2 /t1/2 ) (Pxa0<xa00.05). However, both DISP10 and DISP8 P4 concentrations did not differ from DIB® (677.39xa0±xa016.13xa0μg/cm2 /t1/2 ). For the analysis of released quantities per day of the in vitro test, four periods were considered: 0-24, 24-48, 48-72 and 72-96xa0h. In the first 24xa0h, DISP8 released significantly less P4 than DISP10 or DIB®, which did not differ among them. Between 24 and 48xa0h, DISP10 released significantly more P4 than DIB®. DISP8 released an intermediate P4 amount and did not differ significantly from DIB® or DISP10. Between 48 and 72xa0h, P4 quantity released by DISP10 was significant higher (Pxa0<xa00.01) than that of DIB® and DISP8, which did not differ among themselves. Between 72 and 96xa0h, DISP10 released significantly more P4 than DIB®, and DISP8 released an intermediate amount which did not differ from DIB® or DISP10 (Pxa0<xa00.01). There was interaction between treatment and time (Pxa0=xa00.0024). The diffusion coefficient values were: 1.36 × 10-8 (cm2 /s) for DISP10 and 1.12 × 10-8 (cm2 /s) for DISP8. For the in vivo test, ovariectomized crossbred cows received DIB® (nxa0=xa04) or DISP8 (nxa0=xa08) in an alternate design with a non-balanced sequence (cross-over) added of measures repeated in time referring to 16xa0days of blood samples collection. Samples were analyzed through radioimmunoassay in solid phase using the commercial kit of DPC (Diagnostics Products Corporation). Plasma concentrations of P4 peaked at 4xa0h after the placement of the device, this being the only time in which plasma P4 concentrations differed between DIB® (11.45xa0±xa01.96) compared with DISP8 (9.23xa0±xa01.15xa0ng/mL) (Pxa0=xa00.027). On day 8, plasma P4 concentrations were similar for DIB® (2.44xa0±xa00.09) and DISP8 (1.89xa0±xa00.13xa0ng/mL) (Pxa0=xa00.58) showing that both devices were able to keep P4 concentrations above 1xa0ng/mL in the plasma of the cow during the 16 day in vivo test. In conclusion, devices manufactured with the blend of PHBV/PCL biopolymers can sustain the release of P4 in a similar manner as silicon.

Follicle and corpus luteum size and vascularity as predictors of fertility at the time of artificial insemination and embryo transfer in beef cattle

Two ultrasound based fertility prediction methods were tested prior to embryo transfer (ET) and artificial insemination (AI) in cattle. Female bovines were submitted to estrous synchronization prior to ET and AI. Animals were scanned immediately before ET and AI procedure to target follicle and corpus luteum (CL) size and vascularity. In addition, inseminated animals were also scanned eleven days after insemination to target CL size and vascularity. All data was compared with fertility by using gestational diagnosis 35 days after ovulation. Prior to ET, CL vascularity showed a positive correlation with fertility, and no pregnancy occurred in animals with less than 40% of CL vascularity. Prior to AI and also eleven days after AI, no relationship with fertility was seen in all parameters analyzed (follicle and CL size and vascularity), and contrary, cows with CL vascularity greater than 70% exhibit lower fertility. In inseminated animals, follicle size and vascularity was positive related with CL size and vascularity, as shown by the presence of greater CL size and vascularity originated from follicle with also greater size and vascularity. This is the first time that ultrasound based fertility prediction methods were tested prior to ET and AI and showed an application in ET, but not in AI programs. Further studies are needed including hormone profile evaluation to improve conclusion.