Atualizações no controle do ciclo estral em ovinos / Updates on the control of the estrous cycle in sheep

Nos últimos anos, observou-se um aumento no tamanho do rebanho ovino no país, indicando uma retomada na ovinocultura. Para melhorar a eficiência reprodutiva desses animais, a utilização de biotécnicas tem se mostrado uma ferramenta importante. Dentre essas biotécnicas, destacam-se os protocolos de sincronização do ciclo estral, os quais frequentemente utilizam progesterona associada a gonadotrofinas ou análogos da prostaglandina em duas aplicações. Este artigo tem como objetivo revisar os protocolos de sincronização utilizados em ovinos e apresentar atualizações relevantes sobre os mesmos.(AU)

In recent years, there has been an increase in the size of the sheep herd in the country, indicating a recovery in sheep farming. To improve the reproductive efficiency of these animals, the use of biotechniques has been shown to be an important tool. Among these biotechniques, estrous cycle synchronization protocols stand out, which frequently use progesterone associated with gonadotropins or prostaglandin analogues in two applications. This article aims to review the synchronization protocols used in sheep and present relevant updates about them.(AU)

Assisted Reproductive Technologies (ART) and genome editing to support a sustainable livestock

This article provides an overview of assisted reproductive technologies (ART) and genome engineering to improve livestock production systems for the contribution of global sustainability. Most ruminant production systems are conducted on grassland conditions, as is the case of South American countries that are leaders in meat and milk production worldwide with a well-established grass-feed livestock. These systems have many strengths from an environmental perspective and consumer preferences but requires certain improvements to enhance resource efficiency. Reproductive performance is one of the main challenges particularly in cow-calf operations that usually are conducted under adverse conditions and thus ART can make a great contribution. Fixed-time artificial insemination is applied in South America in large scale programs as 20 to 30% of cows receive this technology every year in each country, with greater calving rate and significant herd genetic gain occurred in this region. Sexed semen has also been increasingly implemented, enhancing resource efficiency by a) obtaining desired female replacement and improving animal welfare by avoiding newborn male sacrifice in dairy industry, or b) alternatively producing male calves for beef industry. In vitro embryo production has been massively applied, with this region showing the greatest number of embryos produced worldwide leading to significant improvement in herd genetics and productivity. Although the contribution of these technologies is considerable, further improvements will be required for a significant livestock transformation and novel biotechnologies such as genome editing are already available. Through the CRISPR/Cas-based system it is possible to enhance food yield and quality, avoid animal welfare concerns, overcome animal health threats, and control pests and invasive species harming food production. In summary, a significant enhancement in livestock productivity and resource efficiency can be made through reproductive technologies and genome editing, improving at the same time profitability for farmers, and global food security and sustainability.(AU)

Applying assisted reproductive technology and reproductive management to reduce CO2-equivalent emission in dairy and beef cattle: a review

Methane emission from beef and dairy cattle combined contributes around 4.5-5.0% of total anthropogenic global methane. In addition to enteric methane (CH4) produced by the rumen, cattle production also contributes carbon dioxide (CO2) (feed), nitrous oxide (N2O) (feed production, manure) and other CH4 (manure) to the total greenhouse gas (GHG) budget of beef and dairy production systems. The relative contribution in standard dairy systems is typically enteric CH4 58%, feed 29% and manure 10%. Herds with low production efficiency can have an enteric CH4 contribution up to 90%. Digestibility of feed can impact CH4 emission intensity. Low fertility herds also have a greater enteric CH4 contribution. Animals with good feed conversion efficiency have a lower emission intensity of CH4/kg of meat or milk. Feed efficient heifers tend to be lean and have delayed puberty. Fertility is a major driver of profit in both beef and dairy cattle, and it is highly important to apply multi-trait selection when shifting herds towards improved efficiency and reduced CH4. Single nucleotide polymorphisms (SNPs) have been identified for feed efficiency in cattle and are used in genomic selection. SNPs can be utilized in artificial insemination and embryo transfer to increase the proportion of cattle that have the attributes of efficiency, fertility and reduced enteric CH4. Prepubertal heifers genomically selected for favourable traits can have oocytes recovered to produce IVF embryos. Reproductive technology is predicted to be increasingly adopted to reduce generation interval and accelerate the rate of genetic gain for efficiency, fertility and low CH4 in cattle. The relatively high contribution of cattle to anthropogenic global methane has focussed attention on strategies to reduce enteric CH4 without compromising efficiency and fertility. Assisted reproductive technology has an important role in achieving the goal of multiplying and distributing cattle that have good efficiency, fertility and low CH4.(AU)

Restrição intrauterina de crescimento: conhecendo seus efeitos sobre o plantel de reprodução / Intrauterine growth restriction: knowing its effects on the breeding herd

A restrição intrauterina de crescimento (RIUC) é a condição na qual o feto não expressa o seu potencial de crescimento de acordo com a idade gestacional. Tal condição ocorre naturalmente na espécie suína, no entanto apresenta forma muito severa, trazendo sérios prejuízos à cadeia suinícola. Os efeitos deletérios da RIUC sobre parâmetros zootécnicos estão bem estabelecidos. No entanto, o conhecimento de tais efeitos sobre parâmetros reprodutivos em machos e fêmeas ainda é limitado. Portanto, a presente revisão tem por objetivo compilar os estudos sobre efeitos da RIUC em parâmetros reprodutivos em machos e fêmeas, bem como intervenções propostas para a diminuição da incidência da condição e de seus efeitos. Achados nesse assunto fornecerão informações valiosas acerca da morfofisiologia reprodutiva de suínos RIUC, estabelecendo estratégias para minimizar as perdas econômicas para o sistema de produção.(AU)

Intrauterine growth restriction (IUGR) is the condition in which the fetus does not express its growth potential according to the gestational age. This condition naturally occurs in the swine species. However, it is very severe and can cause serious losses to the swine production chain. The deleterious effects of IUGR on zootechnical parameters are well established. However, the knowledge of such effects on reproductive parameters in males and females is still limited. Therefore, the present review aims to compile the studies on the effects of IUGR on reproductive parameters in males and females, as well as proposed interventions to decrease the incidence of the condition and its effects. Findings on this issue will provide valuable information about the reproductive morphophysiology of IUGR pigs, establishing strategies to minimize economic losses to the production system.(AU)

Physical and environmental characteristics of the compost barn system and its effects on the physical integrity, reproduction and milk production of dairy cattle: a scoping review

Compost barn (CB), although recent in Brazil, is increasingly gaining popularity among the intensive breeding systems in the dairy sector. This system promises to offer several advantages to producers and animals: such as providing an environment in which milk production is increased and the physical integrity of cattle is improved, reducing mastitis episodes, and promoting thermal comfort for animals. Another factor that highlights CB concerning other intensive systems is the composting process, generated by the deposition of carbon-rich materials (bedding) with nitrogen sources (urine and feces) from animals. For the full benefits of this composting to be achieved, management, especially of bedding, must be carried out correctly, considering the development requirements of the compost, the use of quality organic material, adequate ventilation, and an ideal rate of animal capacity, so that the generation of heat occurs efficiently. However, there is a general lack of information about the CB system. Hence, there is an increasing need for data surveys of Brazilian regions to compare the diversity of materials used in bedding, assessing energy efficiency and performance over time. Therefore, this bibliographical review addressed the main points of the CB system approach, considering that studies such as this are consistently relevant for rural producers, facilitating decisions regarding the implementation and management of the CB system on their farms.

Fatores que impactam na eficiência reprodutiva de vacas de corte / Factors that impact the reproductive efficiency of beef cows

A maior produtividade na pecuária está correlacionada com a eficiência reprodutiva do rebanho. As biotécnicas da reprodução, principalmente os protocolos de sincronização da ovulação, são de grande importância para otimizar a produção e acelerar o ganho genético em rebanhos de corte e de leite. No entanto, alguns fatores como a categoria animal, o manejo reprodutivo implementado na propriedade e o reprodutor utilizado podem afetar os resultados de fertilidade nos protocolos de IATF. Dessa maneira, algumas estratégias foram desenvolvidas para contornar alguns desafios inerentes a vacas de corte em anestro pós-parto e aumentar a eficiência reprodutiva dessas fêmeas. Dentre as estratégias, destacam-se a utilização de progesterona e a suplementação energética/proteica previamente ao início do protocolo de IATF.(AU)

The reproductive efficiency of the herd is correlated with higher productivity in livestock. Reproduction biotechniques as ovulation synchronization protocols are important to optimize production and accelerate genetic profit in beef and dairy herds. However, some factors such as the animal category, the reproductive management implemented on the farm and the sire used can affect the fertility results in the TAI protocols. In this way, some strategies were developed to overcome some challenges of postpartum anestrus beef cows and to increase the reproductive efficiency of these cows. The use of progesterone and energy/protein supplementation before starting the TAI protocol stand out are the strategies.(AU)

Comparison of efficiency between two artificial insemination methods using fresh semen in domestic cat (Felis Catus) / Comparação da eficiência entre dois métodos de inseminação artificial utilizando sêmen fresco em gata doméstica (Felis Catus)

This study aimed to compare domestic cats' pregnancy rates using fresh semen for the bilateral intrauterine insemination (BIUI) method and the novel uterine body insemination (UBI) method. Queens received a single injection of equine chorionic gonadotropin (eCG) (200 IU; IM) to induce ovarian follicular development and, after 83 h, an injection of human chorionic gonadotropin (hCG) (100 IU; IM) for final oocyte maturation and ovulation induction. Thirty-four hours after hCG administration, 3 × 106fresh spermatozoa were used for insemination by the BIUI (n = 8 queens) or by the UBI (n = 7 queens) techniques,respectively. Pregnancy rates were 75.00% (6/8) by BIUI and 42.85% (3/7) by the UBI method. Themean litter size was 3.0 ± 0.86 for the BIUI, and 2.0 ± 1.0 for the UBI method. Spontaneous abortion occurred on day 35 of pregnancy in one queen following the UBI method. Our findings showed that the BIUI of queens with fresh semen resulted in higher pregnancy rates than the novel UBI method; also, acceptable pregnancy rates were achieved following BIUI with fresh semen in the domestic cat.(AU)

O objetivo deste estudo foi comparar as taxas de prenhez em gatas domésticas usando sêmen fresco para o método de inseminação intrauterina bilateral (BIUI) e o novo método de inseminação do corpo uterino (UBI). As gatas receberam uma única injeção de gonadotrofina coriônica equina (eCG) (200 UI; IM) para induzir o desenvolvimento folicular ovariano e, após 83 h, uma injeção de gonadotrofina coriônica humana (hCG) (100 UI; IM) para maturação final do oócito e ovulação indução. Trinta e quatro horas após a administração de hCG, 3 × 106 espermatozoides frescos foram utilizados para inseminação pelas técnicas de BIUI (n = 8 gatas) ou UBI (n = 7 gatas), respectivamente. As taxas de gravidez foram de 75,00% (6/8) pela BIUI e 42,85% (3/7) pelo método UBI. O tamanho médio da ninhada foi de 3,0 ± 0,86 para o método BIUI e 2,0 ± 1,0 para o método UBI. Aborto espontâneo ocorreu no dia 35 de gestação em uma gata seguindo o método UBI. Nossos achados mostraram que a BIUI de gatas com sêmen fresco resultou em maiores taxas de prenhez do que o novo método UBI; também, taxas de prenhez aceitáveis foram alcançadas após BIUI com sêmen fresco no gato doméstico.(AU)

Effect of assisted calving on uterine puerperal disorders occurrence, and on reproductive efficiency in crossbred dairy cows / Efeito do parto assistido na ocorrência de desordens uterinas puerperais e na eficiência reprodutiva de vacas leiteiras mestiças

The aim of this study was to evaluate the effect of the type of calving (normal or assisted) on the occurrence of puerperal uterine disorders and on the number of artificial inseminations (AI) per conception and pregnancy rate at 150 days postpartum (PPD). Cows were observed during parturition and the type of calving was classified as normal or assisted. Normal calving required no human interference, while assisted calving required a calf removal aid via vaginal access. There were 825 births, 7 stillbirths (0.85%) and 17 twins (2.06%). We analyzed 801 single births, from which 766 (95.63%) were normal and 35 (4.36%) assisted. Were evaluated the uterine disorders occurrence such as retained placenta combined with metritis (PR/ME) and clinical endometritis (CE). The overall occurrences were 10.24% (82/801) of RP/ME, 12.86% for CE and 5.12% for RP/ME and CE. Most of normal calving cows had healthy puerperium (73.89%), whereas a majority of assisted calving cows had uterine disorders (74.29%). The number of AI per conception was similar for cows that had either normal or assisted calving (2.39±0.08 and 3.00±0.43, P = 0.16). There was no evidence of negative influence of calving type on the 150 PPD pregnancy rate of lactating crossbreed dairy cows (P = 0.44). Healthy cows had higher 150 PPD pregnancy rate than cows affected by puerperium uterine disorders (51.65 vs. 42.92%). Normal calving crossbred dairy cows had a healthier puerperium, compared to cows with assisted calving which were more susceptible to puerperium uterine disorders. And cows with a health puerperium have a higher pregnancy rate at 150 days postpartum.

Objetivou-se avaliar em vacas leiteiras mestiças que pariram um bezerro vivo, o efeito do tipo de parto (normal ou assistido) na ocorrência de desordens uterinas puerperais e no número de inseminações artificiais (IA) por concepção e taxa de prenhez 150 dias pós-parto (DPP). As vacas foram monitoradas durante o parto e o tipo de parto foi classificado como normal ou assistido. O parto normal não precisou de interferência humana, enquanto o parto assistido precisou de auxílio para retirada do bezerro por via vaginal. Foram registrados 825 partos, sendo 7 natimortos (0,85%) e 17 gemelares (2,06%). Foram analisados 801 partos simples, dos quais 766 (95,63%) foram normais e 35 (4,36%) foram assistidos. Foram avaliadas a ocorrência de desordens uterinas como a retenção de placenta associada com metrite (RP/ME) e endometrite clínica (EC). A ocorrência das doenças foi de 10,24% (82/801) para RP/ME, 12,86% para EC e 5.12% para RP/ME com CE. A maioria das vacas com parto normal tiveram puerpério saudável (73,89%), enquanto a maioria das vacas com parto assistido apresentaram desordens uterinas (74,29%). O número de IA por concepção foi semelhante nas vacas que tiveram parto normal ou assistido (2,39±0,08 e 3,00±0,43, P = 0,16). Não houve evidência de influência negativa do tipo de parto na taxa de prenhez 150 DPP de vacas leiteiras mestiças em lactação (P = 0,44). Vacas saudáveis apresentaram maior taxa de prenhez 150 DPP do que vacas afetadas por desordens uterinas no puerpério (51,65 vs. 42,92%). Vacas leiteiras mestiças com parto normal tiveram um puerpério saudável, comparadas às que tiveram parto assistido, por sua vez foram mais susceptíveis as desordens uterinas no puerpério. E vacas com puerpério saudável resultaram em maiores taxas de prenhez aos 150 dias pós parto.

Exame clínico andrológico em búfalos: particularidades e mercado / Clinical andrological examination in buffaloes: particularities and market

A bubalinocultura tem expandido mundialmente com grande importância socioeconômica na produção de leite, carne e na tração animal. No entanto, algumas características como: a sazonalidade, poucos reprodutores com genética superior para ser multiplicada e reduzido número de touros com sucesso de coleta constante de sêmen nas Centrais, dificultam a obtenção de maiores índices reprodutivos a nível de Brasil. Neste contexto, a eficiência reprodutiva do rebanho possui papel de destaque, consequentemente, o touro bubalino e a realização do exame andrológico são essenciais para o desenvolvimento da bubalinocultura. Apesar da realização de pesquisas ao longo dos anos relacionadas à andrologia em búfalos, na prática a campo ainda existe uma lacuna referente aos aspectos reprodutivos nessa espécie, fazendo com que haja uma demanda por conhecimento específico. Diante disso, objetivou-se abordar alguns dos principais aspectos da andrologia na espécie bubalina, para auxiliar o Médico Veterinário no atendimento clínico e andrológico visando alcançar uma boa eficiência reprodutiva.(AU)

Buffalo farming has expanded worldwide with great socioeconomic importance in the production of milk, meat and animal traction. However, some characteristics such as: seasonality, few sires with superior genetics to be multiplied and reduced number of bulls with constant semen collection success in the Centrals, make it difficult to obtain higher reproductive rates in Brazil. In this context, the reproductive efficiency of the herd plays a prominent role, consequently, the buffalo bull and the performance of the andrological examination are essential for the development of buffalo breeding. Despite conducting research over the years related to andrology in buffaloes, in field practice there is still a gap regarding reproductive aspects in this species, causing a demand for specific knowledge. In view of this, the objective was to address some of the main aspects of andrology in the buffalo species, to assist the veterinarian in clinical and andrological care in order to achieve good reproductive efficiency.(AU)

Adjusted Thr: Lys Ratio Improved the Performance and Efficiency of Japanese Quail

Two hundred and forty Japanese quail aged 125 days were randomly allocated to five treatment groups based on laying (%) and quail's weight (90.71 ± 1.8% egg/day × 100 and 178.05 ± 9.38 g, respectively), each of which included six replicates of eight quails. The diets were formulated based on corn, soybean meal, and industrial amino acids. An optimal diet achieves 100% of amino acids required by the quail requirements, except for threonine. Five treatments were made: 20% less amino acid; 10% less amino acid; optimal diet; 10% more amino acid; and 20% more amino acids than those in the optimal diet. The increase in amino acid levels in a fixed Lys: amino acid ratio led to histological alterations in the liver and uterine epithelium, reduction in blood lipid peroxidation, lower hepatic HSP70 gene expression, and the performance of laying Japanese quail. The optimal diet based on the NRC with an adjusted Thr: Lys 78 ratio (Lys 1.0%) improved the performance and efficiency of Japanese quail from 125 to 230 days of age.(AU)

The equine endometrium and its multiple connections, interrelationships and clinical effects in aged mares

Mares, which make up 90% of animals requiring reproductive assistance in commercial equine production systems, are subjected to strong breeding and reproductive efficiency pressure throughout their lives, but the effects of aging on overall and reproductive systems in particular; it often means that we are forcing the natural homeostasis mechanisms under pressure over time. The objective of this brief communication is to summarize some concepts related to the role and importance of equine endometrium, particularly in old mares, the most challenged category to achieve productive and efficiency goals established by humans. Endometritis is one of the most frequent and recurrent pathologies in equine gynecology and is responsible for enormous economic losses in the industry. Alterations of the microbiota, molecular signals and uterine endocrine microenvironment can lead to infertility, but degenerative phenomena associated with age and parity can lead to endometriosis altering maternal recognition of pregnancy and pregnancy maintenance. Maintaining horses in an adequate nutrition status and environment is essential to achieve pregnancy but also to obtain healthy offspring.(AU)

Casos clínicos de infertilidade em gatos / Clinical cases of infertility in cats

A criação comercial de gato doméstico tem aumentado assim como a realização de estudos para melhorar a eficiência reprodutiva é uma realidade. O interesse pela identificação das falhas reprodutivas tem crescido, entretanto, os casos de infertilidade nos machos são escassos na literatura disponível. O histórico de infertilidade de um gato deve ser investigado cuidadosamente, pois pode estar associado a mudanças no manejo ou doenças. O diagnóstico dessas 'falhas reprodutivas' geralmente é simples, se realizada uma boa anamnese, exames, físico e andrológico, minuciosos, assim como exames complementares, entre eles hemograma completo, perfil bioquímico e testes para doenças infecciosas como FIV, FELV e FIP.(AU)

Commercial breeding of domestic cats has increased, and studies to improve reproductive efficiency are a reality. Interest in identifying reproductive failures has increased, however, cases of infertility in men are scarce in the available literature. A cat's history of infertility should be investigated carefully as it may be associated with changes in management or illness. The diagnosis of these 'reproductive failures' is usually simple if a good anamnesis, thorough physical and andrological examinations are carried out, in addition to complementary tests, including complete blood count, biochemical profile, tests for infectious diseases such as FIV, FELV, FIP.(AU)

Cetose subclínica e seu impacto no desempenho reprodutivo de vacas leiteiras: revisão de literatura / Subclinical ketosis and its impact on the reproductive performance of dairy cows: literature review

A cetose, conhecida também como acetonemia, é um distúrbio metabólico que afeta principalmente vacas leiteiras de alta produção. A elevação anormal de corpos cetônicos nos tecidos e fluidos corporais do animal ocorre devido a um déficit de energia. A quantidade de alimento/nutrientes ingeridos não é suficiente para suprir a demanda corporal do mesmo, assim como a eficiência reprodutiva que está diretamente ligada à saúde, condição corporal e sua capacidade de produção. Animais de alta produção possuem um desafio muito grande de aumentar a produção a cada lactação, com isso, estão susceptíveis a mudanças metabólicas, entre elas a cetose, clínica ou subclínica. Tal enfermidade ocorre devido a uma má adaptação metabólica do animal a sua nova condição de lactante. A elevada incidência de doenças uterinas no pós-parto de vacas leiteiras é responsável por inúmeros prejuízos para a atividade, principalmente pela redução da eficiência reprodutiva das vacas acometidas por infecções. Contudo, visto que a cetose subclínica prevalece nos rebanhos leiteiros de alta produção, o objetivo desta revisão de literatura é apresentar a patogenia e os efeitos que esse distúrbio metabólico têm sobre a reprodução das vacas de aptidão leiteira no após o parto, utilizando de indicadores como taxa de prenhez, taxa de concepção, retorno a ciclicidade, intervalo entre partos e intervalo entre parto e estro.(AU)

Ketosis, also known as acetonemia, is a metabolic disorder that primarily affects high-yielding dairy cows. The abnormal elevation of ketone bodies in the animal's tissues and body fluids occurs due to an energy deficit. The amount of food/nutrients ingested are not enough to supply the body's demand, as well as the reproductive efficiency that is directly linked to health, body condition and its production capacity. High production animals have a very big challenge to increase production with each lactation, therefore, they are susceptible to metabolic changes, including clinical or subclinical ketosis. Such a disease occurs due to a poor metabolic adaptation of the animal to its new lactating condition. The high incidence of uterine diseases in the postpartum period of dairy cows is responsible for numerous losses to the activity, mainly for the reduction of the reproductive efficiency of cows affected by infections. However, since subclinical ketosis prevails in high production dairy herds, the objective of this literature review is to present the pathogenesis and the effects that this metabolic disorder has on the reproduction of dairy cows in the postpartum period, using indicators such as pregnancy rate, conception rate, return to cyclicity, calving interval and calving-estrus interval.(AU)

Use of new recombinant proteins for ovarian stimulation in ruminants

Currently, gonadotropin products (follicle stimulating hormone, FSH, and luteinizing hormone, LH) used in animal reproduction are produced by extraction and purification from abattoir-derived pituitary glands. This method, relying on animal-derived materials, carries the potential risk of hormone contamination and pathogen transmission. Additionally, chorionic gonadotropins are extracted from the blood of pregnant mares (equine chorionic gonadotropin; eCG) or the urine of pregnant women (human chorionic gonadotropin; hCG). However, recent advancements have introduced recombinant gonadotropins for assisted animal reproduction therapies. The traditional use of FSH for superovulation has limitations, including labor requirements and variability in superovulation response, affecting the success of in vivo (SOV) and in vitro (OPU/IVEP) embryo production. FSH treatment for superstimulation before OPU can promote the growth of a homogenous follicular population and the recovery of competent oocytes suitable for IVEP procedures. At present, a single injection of a preparation of long-acting bovine recombinant FSH (rFSH) produced similar superovulation responses resulting in the production of good-quality in vivo and in vitro embryos. Furthermore, the treatment with eCG at FTAI protocol has demonstrated its efficacy in promoting follicular growth, ovulation, and P/AI, mainly in heifers and anestrous cows. Currently, treatment with recombinant glycoproteins with eCG-like activity (r-eCG) have shown promising results in increasing follicular growth, ovulation, and P/AI in cows submitted to P4/E2 -based protocols. Bovine somatotropin (bST) is a naturally occurring hormone found in cows. Recombinant bovine somatotropin (rbST), produced through genetic engineering techniques, has shown potential in enhancing reproductive outcomes in ruminants. Treatment with rbST has been found to improve P/IA, increase donor embryo production, and enhance P/ET in recipients. The use of recombinant hormones allows to produce non-animal-derived products, offering several advantages in assisted reproductive technologies for ruminants. This advancement opens up new possibilities for improving reproductive efficiency and success rates in the field of animal reproduction.(AU)

Effect of adding Spirulina platensis algae to small ruminant rations on productive, reproductive traits and some blood components

This experiment conducted using 20 Rahmani ewes at the last third of pregnancy in two equal groups. One group served as control, while the other group received Spirulina platensis(SP) at the rate of 0.5 gm 10 kg-1live body weight. The objective was to find out the effect of adding Spirulina platensisalgae to small ruminant rations on reproductive and productive traits and blood components of sheep. The experiments lasted for 120 days for both dams and their lambs after weaning. The findings proved that adding SP in ewes' diets had no effect on the average of live body weight change. Average milk yield was significantly (p <0.01) higher in the treatment group than the control. Lamb's birth weight and daily body gain of the treated group were significantly (p <0.01) higher than the control. Blood and serum picture profile of ewes were significantly higher when fed SP additive than the control.It could be concluded that the addition of SP to the ration of sheep positively preserved their health, productive and reproductive status as well as their lambs' growth rate. Also the additive improved the economic efficiency of treated animals by about 53.13%.(AU)

How does reproduction account for dairy farm sustainability?

Sustainability - the new hype of the 21st century has brought discomfort for the government and society. Sustainable agriculture is essential to face our most concerning challenges: climate change, food security, and the environmental footprint, all of which add to consumers' opinions and choices. Improvements in reproductive indexes can enhance animal production and efficiency, guaranteeing profit and sustainability. Estrus detection, artificial insemination (AI), embryo transfer (ET), estrus synchronization (ES), and multiple ovulations are some strategies used to improve animal reproduction. This review highlights how reproductive strategies and genetic selection can contribute to sustainable ruminant production. Improved reproductive indices can reduce the number of nonproductive cows in the herd, reducing methane emissions and land use for production while preserving natural resources.(AU)

Abordagem terapêutica hormonal para cistos foliculares ovarianos em vacas leiteiras - relato de casos / Hormonal therapeutic approach for ovarian follicular cysts in dairy cattle - case reports / Enfoque terapéutico hormonal para quistes foliculares ováricos en vacas lecheras - informe de casos

Vacas de alta produção de leite estão mais sujeitas a desequilíbrios metabólicos pós-parto, influenciando na performance reprodutiva subsequente. Alterações relacionadas a funcionalidade do ovário podem desencadear desequilíbrios hormonais e desordens reprodutivas, como a formação de cistos ovarianos, os quais podem interferir no processo de ovulação e impactar substancialmente na eficiência reprodutiva. Neste estudo de caso em específico, sete vacas leiteiras foram diagnosticadas com a presença de cistos foliculares ovarianos. Foram submetidas a terapia hormonal envolvendo o uso de análogos de Hormônio Liberador de Gonadotrofinas (GnRH) e prostaglandina-F2a (PGF-2a), a qual apresentou resultados satisfatórios. A abordagem terapêutica hormonal tem sido amplamente utilizada devido à sua efetividade na resolução dos cistos ováricos e melhoria da função reprodutiva. É fundamental que o médico veterinário tenha conhecimento clínico sobre a abordagem adequada de cistos ovarianos, a fim de proporcionar saúde e bem-estar aos animais, garantindo bons índices em produção de leite e desempenho reprodutivo.

High milk production cows are more likely to postpartum metabolic imbalances, which may influence subsequent reproductive performance. Changes in ovarian functionality can trigger hormonal alterations and reproductive disorders, such as the formation of ovarian cysts, which can interfere with the ovulation process and substantially impact reproductive efficiency. In this specific case study, seven dairy cows were diagnosed with the presence of ovarian follicular cysts. They were submitted to hormonal therapy involving the use of Gonadotropin-Releasing Hormone (GnRH) and prostaglandin F2a (PGF-2a) analogs, which presented satisfactory results. Hormonal therapeutic approaches have been widely employed due to their effectiveness in resolving ovarian cysts and improving reproductive function. It is essential for the veterinarian to have clinical knowledge about the appropriate management of ovarian cysts in order to provide the health and welfare of the animals, ensuring suitable rates in milk production and reproductive performance.

Las vacas de alta producción de leche tienen mayor probabilidad de desequilibrios metabólicos posparto, lo cual puede influir en el rendimiento reproductivo posterior. Los cambios en la funcionalidad ovárica pueden desencadenar alteraciones hormonales y trastornos reproductivos, como la formación de quistes ováricos, que pueden interferir en el proceso de ovulación y afectar sustancialmente la eficiencia reproductiva. En este estudio de caso específico, se diagnosticó la presencia de quistes foliculares ováricos en siete vacas lecheras. Se sometieron a terapia hormonal que incluyó el uso de análogos de Hormona Liberadora de Gonadotropinas (GnRH) y prostaglandina F2α (PGF-2a), lo cual arrojó resultados satisfactorios. Los enfoques terapéuticos hormonales se han utilizado ampliamente debido a su efectividad en la resolución de quistes ováricos y la mejora de la función reproductiva. Es fundamental que el médico veterinario tenga conocimiento clínico sobre el manejo adecuado de los quistes ováricos para garantizar la salud y el bienestar de los animales, asegurando adecuadas tasas de producción de leche y rendimiento reproductivo.

Group-training of rams at puberty for artificial vagina-mediated semen collection and its influence on semen quality and sexual behavior

There is a paucity of information with respect to group-training for artificial vagina and its influence on semen characteristics and sexual behavior of young untrained rams. A total of 18 healthy Najdi rams (with an initial body weight of 40-45 Kg and 7-8 month-old) were consequently used herein to test the usefulness of group-training for artificial vagina-mediated semen collection during the breeding season. Rams were randomly segregated into three groups (n = 6 rams per protocol), and the whole experiment was lasted for 10 weeks. The 1st group was subjected to a training protocol where one untrained ram was placed for 20 min with a teaser ewe, while the 2nd group were subjected to a protocol where one untrained ram was placed for 20 min with one trained ram and a teaser ewe, whereas the 3rd group were subjected to a protocol where three untrained rams were placed for 20 min with one trained ram and a teaser ewe. The obtained results clearly (P < 0.05) showed that training young rams in group has increased their sperm concentration and sexual stimulation, shortened the period of their training time, and descriptively had a complete training efficiency. The sexual stimulation of young untrained rams was intensified by the competition between rams in the co-presence of a trained ram. Collectively, these data may suggest that group-training of rams at puberty is a better protocol for AV-mediated semen collection compared to individual training. Some shortcomings were noted herein, but research dealing with this subject may very well improve the reproductive performance of young untrained rams.(AU)

Uso da ultrassonografia Doppler colorido na reprodução de pequenos ruminantes / Use of color Doppler ultrasonography in the reproduction of small ruminants

A ultrassonografia (US) Doppler colorido fornece uma ferramenta não invasiva valiosa para detectar e monitorar mudanças dinâmicas na rede vascular e fluxo sanguíneo em vários órgãos e tecidos reprodutivos. Em apoio as biotécnicas da reprodução animal assistida, a US Doppler colorido tem mostrada alta eficiência no monitoramento funcional das estruturas ovarianas. A previsão de respostas ovarianas e produções embrionária em ovinos pela identificação de sinais Doppler na parede folicular já se mostrou eficiente. A aplicação da US Doppler colorido para a identificação da funcionalidade do tecido luteal é ainda maior, desde acompanhamentos fisiológicos e diagnósticos de disfunções luteais até ampla aplicação em conjunto as diferentes biotécnicas reprodutivas. Destaca-se em ovelhas e cabras, a aplicação comercial da US Doppler colorido para o diagnóstico de gestação precoce, de disfunções luteais, de determinação de respostas ovarianas em fêmeas doadoras e receptoras de embriões, para identificar efeitos luteotrófico de estratégias hormonais, e ainda para amparar as estratégias de ressincronização de estro.(AU)

Color Doppler ultrasonography (US) provides a valuable non-invasive tool for detecting and monitoring dynamic changes in the vascular network and blood flow in various reproductive organs and tissues. In support of assisted animal reproduction biotechniques, color Doppler US has shown high efficiency in the functional monitoring of ovarian structures. The prediction of ovarian responses and embryonic production in sheep by identifying Doppler signals in the follicular wall has already proved to be efficient. The application of color Doppler US for identifying the functionality of the luteal tissue is even greater, from physiological monitoring and diagnosis of luteal dysfunctions to wide application together with different reproductive biotechniques. It stands out in sheep and goats, the commercial application of color Doppler US for the diagnosis of early pregnancy, luteal dysfunctions, determination of ovarian responses in embryo donor and recipient females, to identify luteotrophic effects of hormonal strategies, and even to support estrus resynchronization strategies.(AU)

Eficiência de três diluidores inespecíficos na refrigeração do sêmen de coelho (Oryctolagus cuniculus f. domesticus) / Efficiency of three unspecific diluents in refrigeration of rabbit (Oryctolagus cuniculus f. domesticus) semen / Eficiencia de tres diluyentes inespecíficos en la refrigeración de semen de conejo (Oryctolagus cuniculus f. domesticus)

Objetivou-se com este trabalho avaliar a viabilidade seminal de coelhos após refrigeração a 5°C utilizando três diluentes comerciais, indicados para refrigeração de sêmen de outras espécies monogástricas. Foram realizadas dez colheitas de sêmen de cada reprodutor. Os ejaculados de cada coelho eram misturados, obtendo-se um pool de sêmen. Em seguida, o pool heterospérmico foi dividido em três tratamentos, de acordo com o diluente utilizado: BotuDogⓇ (cães); BotuSemen® (equinos); e Beltsville Thawing Solution - BTS (suínos). As amostras foram avaliadas quanto aos parâmetros macroscópicos, microscópicos e funcionais em quatro momentos: sêmen fresco (0 h) e refrigerado (16, 24 e 48 h). Os valores médios de motilidade, vigor e defeitos totais do sêmen fresco foram de 86,0%, 3,05 e 11,5%, respectivamente. Após o início do resfriamento, observou-se comportamento linear decrescente para a motilidade e vigor espermático do sêmen em função do tempo, diferindo (P < 0,05) entre os tratamentos. Destaca-se que o tratamento diluído em BTS apresentou redução na manutenção dos parâmetros avaliados de forma mais pronunciada (P < 0.05) ao longo do tempo, apresentando os menores valores para motilidade e vigor espermático dentro de cada tempo avaliado: 16h [20,6 ± 7,28 e 0,75 (0,375 1,5)], 24h [12,0 ± 6,80 e 0 (0 - 1,0)] e 48h [3,0 ± 2,13 e 0 (0 - 0,125)]. Após 48 h de resfriamento, o BotuDogⓇ foi o que apresentou maior valor para motilidade espermática (71,0 ± 2,08) e, juntamente, com o BotuSemenⓇ apresentaram maior valor para vigor espermático (2,5). De acordo com os dados obtidos os diluentes BotuDogⓇ e BotuSemenⓇ mostraram-se eficientes em manter parâmetros espermáticos adequados, apresentando boa viabilidade espermática em até 48h pós refrigeração a 5°C. Foram obtidos, resultados inéditos quanto a parâmetros espermáticos do sêmen de coelho refrigerado que podem ser utilizados como valores de referência para o manejo reprodutivo e processamento do semen desses animais, visto a inexistênca dessas recomendações técnicas.

The objective of this work was to evaluate the seminal viability of rabbits after refrigeration at 5°C using three commercial diluents, indicated for refrigeration of semen from other monogastric species. Ten semen collections were performed from each breeder. The ejaculates of each rabbit were mixed, obtaining a pool of semen. Then, the heterospermic pool was divided into three treatments, according to the diluent used: BotuDog (dogs); BotuSemenⓇ (horses); and Beltsville Thawing Solution - BTS (pigs). The samples were evaluated for macroscopic, microscopic, and functional parameters in four moments: fresh (0 h) and refrigerated (16, 24, and 48 h) semen. The average values of motility, vigor, and total defects of fresh semen were 86.0%, 3.05 and 11.5%, respectively. After the beginning of cooling, a decreasing linear behavior was observed for motility and sperm vigor of semen as a function of time, differing (P < 0.05) between treatments. It is noteworthy that the treatment diluted in BTS® showed a more pronounced reduction in the maintenance of the evaluated parameters (P < 0.05) over time, with the lowest values for sperm motility and vigor within each evaluated time: 16h [20.6 +7.28 and 0.75 (0.375 - 1.5)], 24h [12.0± 6.80 and 0 (0 - 1.0)] and 48h [3.0±2.13 and 0 (0 - 0.125)]. After 48 h of cooling, BotuDog presented the highest value for sperm motility (71.0 ± 2.08) and, together with BotuSemenⓇ, presented the highest value for sperm vigor (2.5). According to the data obtained, BotuDog and BotuSemenⓇ diluents were efficient in maintaining adequate sperm parameters, showing good sperm viability in up to 48 hours after refrigeration at 5°C. Through this work, unpublished results were obtained regarding spermatic parameters of refrigerated rabbit semen that can be used as reference values for reproductive management and semen processing of these animals, given the lack of these technical recommendations.

El objetivo de este trabajo fue evaluar la viabilidad seminal de conejos después de refrigeración a 5°C utilizando tres diluyentes comerciales, indicados para la refrigeración de semen de otras especies monogástricas. Se realizaron diez colectas de semen de cada reproductora. Se mezclaron los eyaculados de cada conejo, obteniendo un pool de semen. Luego, el pool heterospérmico se dividió en tres tratamientos, según el diluyente utilizado: BotuDogⓇ (perros); BotuSemenⓇ (caballos); y Beltsville Thawing Solution - BTS® (cerdos). Las muestras fueron evaluadas para parámetros macroscópicos, microscópicos y funcionales en cuatro momentos: semen fresco (0 h) y refrigerado (16, 24 y 48 h). Los valores promedio de motilidad, vigor y defectos totales del semen fresco fueron 86,0%, 3,05 y 11,5%, respectivamente. Después del inicio del enfriamiento, se observó un comportamiento lineal decreciente para la motilidad y el vigor espermático del semen en función del tiempo, difiriendo (P < 0.05) entre tratamientos. Cabe destacar que el tratamiento diluido en BTS® mostró una reducción más pronunciada en el mantenimiento de los parámetros evaluados (P<0,05) a lo largo del tiempo, con los valores más bajos de motilidad espermática y vigor dentro de cada tiempo evaluado: 16h [20,6 ± 7,28 y 0,75 (0,375 -1.5)], 24h [12,0 ± 6,80 y 0 (0 - 1,0)] y 48h [3,0±2,13 y 0 (0 - 0,125)]. Después de 48 h de enfriamiento, BotuDogⓇ presentó el valor más alto de motilidad espermática (71,0 +2,08) y, junto con BotuSemenⓇ, presentó el valor más alto de vigor espermático (2,5). De acuerdo con los datos obtenidos, los diluyentes BotuDogⓇ y BotuSemenⓇ fueron eficientes en mantener parámetros espermáticos adecuados, mostrando buena viabilidad espermática hasta 48 horas después de la refrigeración a 5°C. A través de este trabajo se obtuvieron resultados inéditos respecto a parámetros espermáticos de semen de conejo refrigerado que pueden ser utilizados como valores de referencia para el manejo reproductivo y procesamiento de semen de estos animales, dada la falta de estas recomendaciones técnicas.