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1.
Theriogenology ; 123: 100-107, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30296650

RESUMO

An experiment was designed to compare fertility of SexedULTRA 4M™ sex-sorted semen and conventional, non-sex-sorted semen following either fixed-time artificial insemination (FTAI) or split-time artificial insemination (STAI) of mature suckled beef cows. Units of sex-sorted and conventional semen were produced using contemporaneous ejaculates from three commercially available sires. Units of conventional semen were generated with 25.0 × 106 live cells per 0.25 ml straw prior to freezing, and units of sex-sorted semen were generated using the SexedULTRATM Genesis III sorting technology with 4.0 × 106 live cells per 0.25 ml straw prior to freezing. Sex-sorted units were sorted to contain X chromosome-bearing sperm cells at an accuracy level of >90%. Cows (n = 1620) across four herds were treated with the 7-d CO-Synch + CIDR protocol [administration of gonadotropin-releasing hormone (GnRH) and insertion of a progesterone insert (CIDR) on Day -10, followed by administration of prostaglandin F2α (PG) and removal of CIDR inserts on Day -3]. Cows were preassigned based on age, body condition score, and days postpartum to one of the following four treatments: FTAI with SexedULTRA 4M™ sex-sorted semen, FTAI with conventional semen, STAI with SexedULTRA 4M™ sex-sorted semen, or STAI with conventional semen. On Day -3, estrus detection aids (Estrotect®) were applied. For cows in FTAI treatments, AI was performed on Day 0 at 66 h after PG administration and CIDR removal, and 100 µg GnRH was administered concurrent with AI. For cows in STAI treatments, AI was performed on either Day 0 or 1, at 66 or 90 h after PG administration and CIDR removal, based on timing of estrus expression. On Day 1 at 90 h after PG administration and CIDR removal, 100 µg GnRH was administered concurrent with AI to any STAI-treated cows that had failed to express estrus. Pregnancy rates to AI were affected (P = 0.04) by the interaction of bull and semen type. Greater pregnancy rates were obtained with conventional semen versus SexedULTRA 4M™ sex-sorted semen when using semen from Bull A (64% [176/277] versus 36% [100/278]; P < 0.0001) and Bull B (72% [200/277] versus 57% [156/276]; P < 0.01), whereas pregnancy rates to AI did not differ between conventional and SexedULTRA 4M™ sex-sorted semen when using semen from Bull C (58% [149/258] versus 52% [131/254]). Pregnancy rates did not differ significantly between cows inseminated using a STAI versus FTAI approach, regardless of whether insemination was performed with conventional semen (65% [265/409] versus 65% [260/403] or SexedULTRA 4M™ sex-sorted semen (50% [200/403] versus 48% [187/405]). However, due to the additional 24 h for potential estrus expression when performing STAI, total estrous response prior to AI was greater (P < 0.001) among cows receiving STAI (84%; 686/812) compared to FTAI (72%; 585/808), and greater pregnancy rates (P < 0.0001) were obtained among cows that expressed estrus prior to AI. In summary, the relative fertility of SexedULTRA 4M™ sex-sorted semen and conventional semen varied across bulls. Although overall pregnancy rates to timed AI did not differ between STAI and FTAI approaches, use of a STAI approach allowed for greater total estrous response prior to AI. Therefore, to achieve acceptable conception rates per unit and service the maximum number of cows with sex-sorted semen, one viable approach may be to use STAI to maximize total estrous response and restrict use of SexedULTRA 4M™ sex-sorted to only those cows expressing estrus.


Assuntos
Inseminação Artificial/veterinária , Sêmen/fisiologia , Pré-Seleção do Sexo/veterinária , Animais , Bovinos/fisiologia , Feminino , Masculino , Gravidez , Taxa de Gravidez , Espermatozoides , Fatores de Tempo
2.
Theriogenology ; 118: 126-129, 2018 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-29890429

RESUMO

The objective of this study was to compare conception rates of female beef cattle inseminated at a fixed-time with either conventional (CON) or SexedUltra™ sex-sorted (SU) semen. Treatments included CON or SU with two sires represented within each treatment. Cows (n = 316) and heifers (n = 78) from six locations were randomly assigned treatment. Ovulation was synchronized in all females using the industry-standard 7-d CO-Synch + controlled internal drug release (CIDR) protocol (100 µg GnRH + CIDR [1.38 g progesterone] on d 0, 25 mg PGF2α at CIDR removal on d 7, and 100 µg GnRH on d 10, 54 h (heifers) or 60 h (cows) after CIDR removal). Estrotect™ estrous detection aids were applied at CIDR removal and patch activation was recorded at insemination. Animals were assumed estrual if greater than 50% of the patch coating was removed. The results from this study indicated no main effects of treatment (P = 0.82), sire (P = 0.64), or age (P=0.8) on AI conception rates. Additionally, there were not significant interactions between sire and treatment (P=0.19) or age and treatment (P=0.29). There was however, a significant (P=0.0005) effect of estrous expression on conception rates. Conception rate for estrual females (62.8%) was greater (p=0.0001) than non-estrual females (38.7%) at FTAI regardless of treatment. Furthermore, the conception rates were similar (P = 0.61) between conventional (61.9%) and sex-sorted semen (63.8%) when estrus was expressed prior to FTAI. Larger studies are warranted to determine appropriate timing of insemination with sex-sorted semen in FTAI protocols to maximize pregnancy potential.


Assuntos
Fertilização/fisiologia , Inseminação Artificial/veterinária , Sêmen/fisiologia , Pré-Seleção do Sexo/veterinária , Animais , Bovinos , Estro , Detecção do Estro/métodos , Feminino , Inseminação Artificial/métodos , Ovulação , Gravidez , Fatores de Tempo
3.
Meat Sci ; 81(1): 15-21, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22063957

RESUMO

Our objective was to determine the effects of vitamin A restriction during finishing on color display life, lipid oxidation, and sensory traits of longissimus lumborum (LL) and triceps brachii (TB) steaks from early and traditionally weaned steers. Forty-eight steers weaned at either 137±26 days (EW) or 199±26 days (TW) were supplemented with either 15,400IU/kg dry matter of vitamin A (HA) or restricted to no supplemental vitamin A (LA) during finishing for 210 and 150 days, respectively. Both LL and TB steaks from the HA steers had the darkest (P<0.05) color scores after 3 days of retail display in PVC packaging at 2°C, and the highest (P<0.05) thiobarbaturic acid reactive substances (TBARS) values. Instrumental a∗, b∗, and saturation index values were lowest (P<0.05) in LL steaks from the HA steers. Instrumental L∗ values were lower (P<0.05) on days 4-6 in TB steaks from TW steers fed LA than those from EW steers fed HA. No differences were found in Warner-Bratzler shear force values or sensory traits in either muscle. No supplemental vitamin A versus high levels of vitamin A inclusion in finishing diets has potential to increase color display life and reduce lipid oxidation, with no effects on meat palatability.

4.
Meat Sci ; 81(4): 596-606, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20416585

RESUMO

Angus crossbred steers (n=48) were either early-weaned (EW) at 137 days or weaned at a traditional age (TW) of 199 days to determine effects of weaning age and dietary vitamin A on serum and liver retinol, carcass traits, and lipid composition. Steers from both weaning ages were allotted to receive either 42,180IU vitamin A/day (HA) or no supplemental vitamin A (NA). Early-weaned and TW steers consumed vitamin A treatments for 235 and 175 days, respectively. Serum and liver retinol of HA steers were dramatically higher (P<0.01) than those of NA steers at the end of finishing. Steers were harvested in two groups 35 days apart at an average ultrasound 12th rib fat thickness of 1.0cm. Live and HCW were similar (P>0.10) between NA and HA steers, but HA steers had numerically greater (P⩾0.10) fat thickness (1.05 vs. 0.87cm). Marbling score and %IMF fat were numerically (P>0.10) higher for EWNA than EWHA steers. Ratio of marbling score/12th rib fat thickness was greater (P=0.08), and ratios of either marbling or %IMF per unit of 12th rib fat thickness, days on finishing diet, unit of HCW, and tenth of yield grade consistently favored steers fed NA, particularly EW steers. Proportions of serum fatty acids changed (P<0.05) during finishing; proportions of individual fatty acids of the longissimus muscle did not change. Restricting vitamin A during finishing has potential to increase carcass marbling and to decrease waste fat, particularly for EW.

5.
J Anim Sci ; 85(11): 3062-71, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17785601

RESUMO

Forty crossbred wethers (BW = 28.7 kg) were used to evaluate the effects on LM lipid composition of diets containing high and low levels of vitamin A. Four treatments arranged as a 2 x 2 factorial with a completely random design were investigated: backgrounding (BG) and finishing (FN) with no supplemental vitamin A (LL); BG with no supplemental vitamin A and FN with high vitamin A (6,600 IU/kg of diet, as fed) supplementation (LH); BG with high vitamin A supplementation and FN with no vitamin A supplementation (HL); and BG and FN with high vitamin A (HH) supplementation. Diets included cracked corn (62.4%), soybean meal (16.0%), cottonseed hull pellets (14.8%), and supplement (7%), and contained <100 IU of vitamin A/kg (as fed) from carotenes before vitamin A was added. During the BG period (d 1 to 56), feed intake was restricted to achieve 0.22 kg of ADG. During the FN period (d 57 to 112), lambs consumed the same diet ad libitum. Lambs were weighed every 14 d, and blood was sampled every 28 d to evaluate changes in serum fatty acids and vitamin A levels. Lambs were slaughtered after 112 d. Lipid composition was determined for liver and LM. There were no treatment differences (P > 0.05) in feed intake, ADG, or final BW. Carcass weights were not affected by vitamin A treatment (P > 0.20), although backfat thickness tended to be different between HL and LL lambs (0.80 vs. 0.64 cm, respectively; P = 0.08). Carcasses from the HH group had greater (P < 0.05) marbling scores than those from the LL group (514 vs. 459) and had 25.8% more extractable intramuscular lipids (3.88 vs. 3.08% for HH and LL, respectively; P < 0.05); the LH and HL treatments were intermediate. Interestingly, the LL group had the greatest increase in serum fatty acids throughout the experimental period (change of 127 vs. 41 microg/g for LL and HH, respectively; P < 0.01). The degree of saturation of fatty acids was not affected by treatment (P = 0.18) in the serum but was affected in the longissimus thoracis fat. Oleic acid increased and linoleic acid decreased in the longissimus thoracis of HH-treated lambs (P < 0.02). These data suggest that increases in total intramuscular lipids may be achieved with high levels of vitamin A supplementation for 112 d in young lambs.


Assuntos
Lipídeos/sangue , Carne/normas , Músculo Esquelético/química , Ovinos/crescimento & desenvolvimento , Vitamina A/administração & dosagem , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Animais , Suplementos Nutricionais , Relação Dose-Resposta a Droga , Fígado/química , Fígado/metabolismo , Masculino , Músculo Esquelético/metabolismo , Distribuição Aleatória , Ovinos/sangue , Ovinos/metabolismo , Vitamina A/metabolismo , Vitaminas/administração & dosagem , Vitaminas/metabolismo , Aumento de Peso
6.
Pediatr Emerg Care ; 15(5): 318-21, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10532658

RESUMO

OBJECTIVE: The purpose of this study was: 1) to evaluate the role of the pediatric emergency department (PED) in placing peripherally inserted midline or central catheters (long lines), and 2) to review indications and complications to use this technology to reduce the number and duration of admissions and provide an alternative method for administering intravenous therapy. METHODS: Retrospective chart review of all patients taken from a procedure log who had long lines placed in the emergency department of a children's hospital. RESULTS: Twenty-eight patients had 30 long line insertions over a 36-month period. Fourteen were female; age ranged from 1 to 36 years with a median of 9 and a mean of 11.1 +/- 8.4. The indication for insertion was for parenteral antibiotics in 27 of 28 (96%) patients and for parenteral nutrition in 1 (4%) patient. The catheters varied in length from 8 to 60 cm. Twelve of 30 (40%) catheters terminated centrally in the subclavian or superior vena cava, while 18 (60%) were in the peripheral cephalic, basilic, or axillary veins. Chest radiography confirmed positioning in 12 of 12 inserted centrally and in 15 of 18 (83%) in the peripheral circulation. Half of the patients received no premedication for the procedure; 10 (33%) received topical anesthetic cream; 2 (7%) local infiltration of anesthetic, and 2 (7%) parenteral sedation. Twenty-one of 30 (70%) patients were discharged directly from the emergency department; 3 (10%) were discharged after admission to the hospital to complete treatment at home with their long lines, and 6 (20%) used their long lines for in-hospital therapy only. Eight of 30 (27%) placements were for patients specifically referred to the PED for placement or replacement of a long line. Twelve of 30 (40%) lines were placed in children presenting for intravenous therapy for cellulitis. These patients received a long line with home i.v. therapy instead of the traditional admission. The duration of intravenous treatment documented for all patients ranged from 1 to 62 days with a median of 10.5, and a mean of 16.2 +/- 17.8, compared with the duration of the line ranging from 1 to 28 days with a median of 4, and a mean of 7.3 +/- 8.0. Ten of 30 (33%) had their line for 3 days or less. The short duration was due to problems with line function in 5 of 10, and intentional removal secondary to improved cellulitis in 5. There were no significant complications with the lines reported during placement or while in use; however, 8 of 30 (27%) of the lines placed developed problems with function, requiring repair or replacement. CONCLUSIONS: 1) Long lines can be inserted in the pediatric emergency department by physicians with different levels of training with minor complications and no adverse clinical effects; 2) the placement of long lines can eliminate the need for hospitalization in some cases, reduce the duration of hospitalization in others, and lessen the need for repeated venipunctures for routine peripheral catheter replacement in patients requiring i.v. therapy; 3) the planned duration of therapy as well as other factors not analyzed in this study should be considered when selecting patients for long line placement in the emergency department.


Assuntos
Antibacterianos/administração & dosagem , Cateterismo Venoso Central , Cateteres de Demora , Serviço Hospitalar de Emergência , Terapia por Infusões no Domicílio , Adolescente , Adulto , Cateterismo Venoso Central/instrumentação , Cateterismo Venoso Central/métodos , Criança , Pré-Escolar , Medicina de Emergência/organização & administração , Falha de Equipamento , Feminino , Humanos , Lactente , Infecções/tratamento farmacológico , Infusões Intravenosas , Masculino , Massachusetts , Pediatria , Estudos Retrospectivos
7.
Pediatr Emerg Care ; 15(2): 106-9, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10220080

RESUMO

Pneumocephalus or air within the cranial vault is usually associated with disruption of the skull caused by head trauma, neoplasms, or after craniofacial surgical interventions. We report a child who presented with headache and the pathognomonic "succussion splash" and was found to have atraumatic pneumocephalus from forceful valsalva maneuvers. Pneumocephalus forms, caused by either a ball-valve mechanism that allows air to enter but not exit the cranial vault, or cerebrospinal fluid (CSF) leaks, which create a negative pressure with subsequent air entry. We review the literature for traumatic and atraumatic causes of pneumocephalus, its complications, and therapy.


Assuntos
Pneumocefalia/etiologia , Manobra de Valsalva , Criança , Feminino , Cefaleia/etiologia , Humanos , Pneumocefalia/diagnóstico , Pneumocefalia/terapia , Tomografia Computadorizada por Raios X
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